Tag Archives: Moon

The moon has a new crater — this time, created by a rogue rocket

A piece of space junk just impacted right into the far side of the moon, creating a shiny new crater as wide as 20 meters (65 feet). The debris, a discarded part of a rocket the size of a school bus, had been floating in space for over seven years – finally ending its long-term trajectory by heading right into the lunar surface at 5,800 miles per hour.

But the controversy around the object is far from over.

Image credit: Pixabay.

We still don’t know a lot of details about the impact. The crash took place on the far side of the moon, meaning it was out of the reach of ground-based telescopes. NASA’s Lunar Reconnaissance Orbiter wasn’t likely in a position to observe the crash, but the agency has already said it will seek out the resulting crater — but the process will take weeks or even months.

“NASA’s Lunar Reconnaissance Orbiter will use its cameras to attempt to identify the impact site and determine any potential changes to the lunar environment resulting from this object’s impact,” an agency spokesman told The Wall Street Journal. “The search for the impact crater will be challenging and might take weeks to months.”

It’s the first known unintentional lunar collision involving a piece of space hardware, not considering the probes that crashed while attempting to land on the moon. The crater is estimated to be located near the naturally-formed Hertzsprung Crater, which is 570 kilometers (354 miles) wide. This will be confirmed by NASA with further work.

The origin of the rocket

Astronomers have long debated the exact identity of the rocket. It’s an upper state booster discarded from a high-altitude satellite launch – either a SpaceX rocket launched in 2015 or a Chinese rocket launched in 2014. However, both have denied ownership. It’s roughly 12 meters long (40 feet) and weighs about 4,500 kilograms.

The first one to predict the impact on the moon was astronomer Bill Gray, who is in charge of the Project Pluto program that monitors faraway space objects. Gray initially calculated that the impactor was the upper stage of a SpaceX rocket launched in 2015, but then corrected his prediction and suggested it was likely the Chinese rocket.

So it’s a complicated story, one that will probably continue to be debated, at least until we get a more detailed view of the crash site. The Lunar Reconnaissance Orbiter has captured the lunar surface in much detail, including things left behind by astronauts. Experts will have to go through before-and-after photos of the specific spot where the rocket impacted to better identify the crater.

The shape of the crater and the dust that came out of it should show how the rocket was oriented at the time of impact, Paul Hayne, an astrophysics professor at the University of Colorado Boulder wrote in The Conversation. A vertical orientation would produce a circular feature, while an asymmetric debris pattern might indicate a belly flop.

If observations are done fast, the lunar orbiter’s infrared instrument could detect glowing-hot material inside the crater, Hayne explained. This could be used to estimate the amount of heat generated from the impact. If using the orbiter fast enough isn’t an option, NASA could also use high-resolution images to estimate the amount of melted material in the crater.

In addition to helping settle the debate on where the object came from, studying the impact site could be useful for another reason. Crater formation is a persistent phenomenon in the Solar System but the physics of the process is not well understood yet. That’s why observing the rocket impact and the resulting crater might be very valuable for scientists to produce better impact simulations – also improving our knowledge of the lunar surface properties.

China builds the world’s first artificial moon

Chinese scientists have built an ‘artificial moon’ possessing lunar-like gravity to help them prepare astronauts for future exploration missions. The structure uses a powerful magnetic field to produce the celestial landscape — an approach inspired by experiments once used to levitate a frog.

The key component is a vacuum chamber that houses an artificial moon measuring 60cm (about 2 feet) in diameter. Image credits: Li Ruilin, China University of Mining and Technology

Preparing to colonize the moon

Simulating low gravity on Earth is a complex process. Current techniques require either flying a plane that enters a free fall and then climbs back up again or jumping off a drop tower — but these both last mere minutes. With the new invention, the magnetic field can be switched on or off as needed, producing no gravity, lunar gravity, or earth-level gravity instantly. It is also strong enough to magnetize and levitate other objects against the gravitational force for as long as needed.

All of this means that scientists will be able to test equipment in the extreme simulated environment to prevent costly mistakes. This is beneficial as problems can arise in missions due to the lack of atmosphere on the moon, meaning the temperature changes quickly and dramatically. And in low gravity, rocks and dust may behave in a completely different way than on Earth – as they are more loosely bound to each other.

Engineers from the China University of Mining and Technology built the facility (which they plan to launch in the coming months) in the eastern city of Xuzhou, in Jiangsu province. A vacuum chamber, containing no air, houses a mini “moon” measuring 60cm (about 2 feet) in diameter at its heart. The artificial landscape consists of rocks and dust as light as those found on the lunar surface-where gravity is about one-sixth as powerful as that on Earth–due to powerful magnets that levitate the room above the ground. They plan to test a host of technologies whose primary purpose is to perform tasks and build structures on the surface of the Earth’s only natural satellite.

Group leader Li Ruilin from the China University of Mining and Technology says it’s the “first of its kind in the world” that will take lunar simulation to a whole new level. Adding that their artificial moon makes gravity “disappear.” For “as long as you want,” he adds.

In an interview with the South China Morning Post, the team explains that some experiments take just a few seconds, such as an impact test. Meanwhile, others like creep testing (where the amount a material deforms under stress is measured) can take several days.

Li said astronauts could also use it to determine whether 3D printing structures on the surface is possible rather than deploying heavy equipment they can’t use on the mission. He continues:

“Some experiments conducted in the simulated environment can also give us some important clues, such as where to look for water trapped under the surface.”

It could also help assess whether a permanent human settlement could be built there, including issues like how well the surface traps heat.

From amphibians to artificial celestial bodies

The group explains that the idea originates from Russian-born UK-based physicist Andre Geim’s experiments which saw him levitate a frog with a magnet – that gained him a satirical Ig Nobel Prize in 2000, which celebrates science that “first makes people laugh, and then think.” Geim also won a Nobel Prize in Physics in 2010 for his work on graphene.

The foundation of his work involves a phenomenon known as diamagnetic levitation, where scientists apply an external magnetic force to any material. In turn, this field induces a weak repulsion between the object and the magnets, causing it to drift away from them and ‘float’ in midair.

For this to happen, the magnetic force must be strong enough to ‘magnetize’ the atoms that make up a material. Essentially, the atoms inside the object (or frog) acts as tiny magnets, subject to the magnetic force existing around them. If the magnet is powerful enough, it will change the direction of the electrons revolving around the atom’s nuclei, allowing them to produce a magnetic field to repulse the magnets.

Diamagnetic levitation of a tiny horse. Image credits: Pieter Kuiper / Wiki Commons.

Different substances on Earth have varying degrees of diamagnetism which affect their ability to levitate under a magnetic field; adding a vacuum, as was done here, allowed the researchers to produce an isolated chamber that mimics a microgravity environment.

However, simulating the harsh lunar environment was no easy task as the magnetic force needed is so strong it could tear apart components such as superconducting wires. It also affected the many metallic parts necessary for the vacuum chamber, which do not function properly near a powerful magnet.

To counteract this, the team came up with several technical innovations, including simulating lunar dust that could float a lot easier in the magnetic field and replacing steel with aluminum in many of the critical components.

The new space race

This breakthrough signals China’s intent to take first place in the international space race. That includes its lunar exploration program (named after the mythical moon goddess Chang’e), whose recent missions include landing a rover on the dark side of the moon in 2019 and 2020 that saw rock samples brought back to Earth for the first time in over 40 years.

Next, China wants to establish a joint lunar research base with Russia, which could start as soon as 2027.  

The new simulator will help China better prepare for its future space missions. For instance, the Chang’e 5 mission returned with far fewer rock samples than planned in December 2020, as the drill hit unexpected resistance. Previous missions led by Russia and the US have also had related issues.

Experiments conducted on a smaller prototype simulator suggested drill resistance on the moon could be much higher than predicted by purely computational models, according to a study by the Xuzhou team published in the Journal of China University of Mining and Technology. The authors hope this paper will enable space engineers across the globe (and in the future, the moon) to alter their equipment before launching multi-billion dollar missions.

The team is adamant that the facility will be open to researchers worldwide, and that includes Geim. “We definitely welcome Professor Geim to come and share more great ideas with us,” Li said.

This rock fragment is over 4 billion years old. It may formed on Earth but ended up on the moon due to a massive asteroid impact. Credit: USRA/LPI.

Earth’s oldest rock was actually found on the moon and brought home by Apollo 14

In 1971, Apollo 14 astronauts brought home various minerals and rock samples from their brief lunar voyage. For decades, these lunar rocks have stayed in storage, occasionally being revisited by researchers curious to try out a new technique in order to learn more about the moon’s geochemistry. Imagine the surprise when scientists found in 2019 that one such rock was terrestrial in origin — to top it all off, it may very well be Earth’s oldest rock found thus far.

This rock fragment is over 4 billion years old. It may formed on Earth but ended up on the moon due to a massive asteroid impact. Credit: USRA/LPI.

This rock fragment is over 4 billion years old. It may have formed on Earth but ended up on the moon due to a massive asteroid impact. Credit: USRA/LPI.

This adventurous moon rock has quite the backstory. According to an international team of researchers, the two-gram piece of quartz, feldspar, and zircon was found embedded in a larger rock called Big Bertha. This combination of minerals shouldn’t be found on the moon but they’re quite common here on Earth. Quartz and zircon form in oxidized systems such as Earth, in high temperature and pressure environments experienced deep below the planet’s crust.

Since zircon contains uranium, whose half-life is predictable, the international team of researchers were able to confidently date the rock to about 4 to 4.1 billion years ago, corresponding to the Hadean Eon of Earth’s geological history. They also determined — based on the sample’s geochemical properties — that it must have formed at a depth of about 20 kilometers (12.4 miles) beneath Earth’s surface.

The Moon rock “Big Bertha”, collected during the 1971 Apollo 14 mission, contains an Earth meteorite that is 4 billion years old. Credit: Wikimedia Commons.

So, how did it end up on the moon? The most plausible explanation is that a massive asteroid impact hurled this traveling mineral into space and eventually crashed into Earth’s natural satellite, which happened to look a lot different than we know it.

For starters, the moon was about three times closer to Earth than it is today. Around 4 billion years ago, the planet was regularly bombarded by cosmic objects of all shapes and sizes, some responsible for producing craters thousands of kilometers in diameter on Earth — so the impactor hypothesis isn’t that far-fetched of an explanation at all. Once on the moon, the rock was further sculpted by new impacts which melted and altered it into a new kind of rock about 3.9 billion years ago. These forces also buried it deep below the lunar surface.

The Moon was much closer to the Earth than it is today when the rock fragment was produced and ejected from the Earth. Credit: LPI/David A. Kring.

The Moon was much closer to the Earth than it is today when the rock fragment was produced and ejected from the Earth. Credit: LPI/David A. Kring.

The rock probably stayed buried for eons until around 26 million years ago when another asteroid impact, this time on the moon, produced the 340-meter wide Cone Crater. Finally, Apollo 14 astronauts found the rock and reunited it with mother Earth.

“It is an extraordinary find that helps paint a better picture of early Earth and the bombardment that modified our planet during the dawn of life,” said Dr. David Kring, co-author of the new study and a researcher at the Lunar and Planetary Institute (LPI).

This may all sound a bit ridiculous, but this is the most plausible explanation. For the minerals to have formed on the moon, Science Alert writes that they must have formed 30 to 70 kilometers below the surface, in an “unusually oxidizing magmatic environment with oxygen levels much higher than those in the lunar mantle 4 billion years ago.” Theoretically, the fragment may have formed in weirdly water-rich pockets of magma deep within the ancient moon but it seems much more likely that the rock formed within our planet’s crust and later got jettisoned to the moon by one of the many daily meteor impacts that bombarded early Earth. 

Of course, there’s a lot of speculation involved in this scenario and the geological community at large is not so easily convinced. Researchers will have to verify this assumption by studying other lunar samples collected thus far. Hopefully, more new samples will be retrieved in the future now that NASA plans on returning humans to the moon.

The other candidate for the oldest material of terrestrial origin is a piece of zircon mineral dated from 4.4 billion years ago enclosed in a sandstone conglomerate in the Jack Hills of the Narryer Gneiss Terrane of Western Australia. However, the dating has been disputed. Furthermore, the fragment is debris left over from that disintegrated long ago. By contrast, the Apollo 14 fragment is much better preserved since it didn’t endure millions of years of weathering. 

The oldest material of extraterrestrial origin found thus far are silicon carbide particles of the Murchison meteorite, which have been determined to be 7 billion years old, billions of years older than the 4.54 billion years age of Earth itself.

The findings appeared in the journal Earth and Planetary Science Letters.

Astronomers find moon-forming disk around exoplanet

Artist impression of the circumplanetary disk surrounding PDS 70c. Credit: ESO/ALMA.

In the early 1990s, scientists knew about a handful of exoplanets (planets outside the solar system). Since then, more than 4,000 exoplanets have been confirmed with thousands more up for investigation. Indeed, technology and astronomers’ skills have grown tremendously. So much so that we can now peer inside certain exoplanets and determine their composition or atmosphere, as well as tell whether some have moons orbiting them. Now, astronomers have upped their game once more, reporting the discovery of a disk of gas and matter surrounding a planet that is supposed to coalesce into a new moon.

The novel discovery was made in the PDS70 star system, located relatively closeby, about 370 light-years from Earth in the constellation Centaurus. Astronomers working with the European Southern Observatory’s (ESO) Atacama Large Millimeter/submillimeter Array (ALMA) found that the system consists of at least two huge Jupiter-sized planets, along with a dust-rich circumstellar disk about as large in width as the distance from the Sun to Earth’s orbit.

Both gas giants feed on the dust disk, funneling material towards them by gravity. So, essentially, these young planets, unceremoniously named PDS 70b and PDS 70c, are still a work in progress.

“More than 4,000 exoplanets have been found until now, but all of them were detected in mature systems,” says Miriam Keppler, co-author of the new study and researcher at the Max Planck Institute for Astronomy in Germany. “PDS 70b and PDS 70c, which form a system reminiscent of the Jupiter-Saturn pair, are the only two exoplanets detected so far that are still in the process of being formed.”


This image shows wide (left) and close-up (right) views of the moon-forming disk surrounding PDS 70c, a young Jupiter-like planet nearly 400 light-years away. The close-up view shows PDS 70c and its circumplanetary disk center-front, with the larger circumstellar ring-like disk taking up most of the right-hand side of the image. Credit: ALMA (ESO/NAOJ/NRAO)/Benisty et al.

But the researchers noticed something else too. When they zoomed in on the high-resolution observations in submillimeter light performed by ALMA, the astronomers uncovered a circumplanetary disk surrounding PDS 70c. The disk was so well defined that its size could be ascertained, being roughly 500 times larger than Saturn’s rings.

This moon-making disk is most likely made of the same material as the much larger looming circumstellar disk that was collected by PDS 70c as the planet swept its orbit. Over millions of years, the researchers believe all of this matter will join together to form a new satellite, similar to how planets form around the sun from the much larger circumstellar disk. In fact, there may be enough material to make three satellites the size of Earth’s Moon.

Subsequent observations should serve to confirm that the object in question around PDS 70c is indeed a circumplanetary disk. If that’s the case, these observations could prove invaluable in clarifying how exomoons form and validating existing theories concerning their formation. ESO’s Extremely Large Telescope (ELT), currently under construction on Cerro Armazones in the Chilean Atacama desert, will be ideal for this task.

“The ELT will be key for this research since, with its much higher resolution, we will be able to map the system in great detail,” says co-author Richard Teague, a co-author and Submillimeter Array (SMA) fellow at the CfA.

The findings were reported in The Astrophysical Journal Letters.

Why don’t satellites fall down from the sky?

Image via Pixabay.

Satellites are able to stay in Earth’s orbit thanks to a perfect interplay of forces between gravity and their velocity. The satellite’s tendency to escape into space is canceled out by Earth’s gravitational pull so that it is in perfect balance. This is the same principle that explains how natural satellites, such as the moon, become locked in a planet’s orbit.

But some very smart people had to run some very complicated math to design the perfect satellite launch. If the satellite moves too fast, it escapes into space. Too slow and it is destined to crash into the atmosphere.

With the right distance, speed, and trajectory, an object can defy Earth’s gravitational pull for quite a long time. In fact, gravity — the same force that is trying to drag these down to the surface — is a vital force in keeping satellites orbiting around our planet.

And to make it entertaining, we’re going to start with rollercoasters.

Perpetually falling

If you’ve ever been on a rollercoaster, you’ll know that strange sensation you get in your gut around bends or hills. Physically speaking, that sensation is produced by inertia; although the cart is changing directions, your body is resisting this shift. You’re strapped in safely to the cart, but your internal organs have a bit more leeway to move. So, for a few moments, they essentially keep moving on the old trajectory, while the rest of your body is on a new one.

This process is summarized neatly in the first law of motion: an object, either moving in a straight line or at rest, will maintain that state until acted upon by an external force. “External force” here can mean a great many things, from air resistance to gravity to you hitting a flying ball with a bat.

Artificial and natural satellites rely on this law to stay above the clouds. Since there is no air resistance in space, once a body gets moving, there’s virtually nothing to slow it down. It doesn’t lose kinetic energy (momentum), so it can keep moving forever.

The satellites we build today get their energy from the rockets that bring them to orbit. They do have internal fuel supplies and thrusters, but these aren’t used to maintain speed. They’re for maneuvers such as avoiding debris or shifting orbits. Rockets impart the satellites they carry with quite a lot of energy, as they need to travel at speeds of at least 17,600 mph (28,330 km/h) to be able to escape Earth’s gravity. After separation from the satellite, this leaves enough energy to keep that satellite in orbit around the Earth for several decades, even a few centuries.

Still, the purpose of a satellite is to stay closeby (relatively speaking) so it can beam our social media posts all over the world. But from what we’ve seen so far, shouldn’t they just travel into space forever? Yes. But there’s one other force at play here — gravity. While momentum keeps satellites moving, gravity is what keeps them in our orbit.

If you fill a bucket with water and spin it really fast, you’ll see that the water won’t pour out of it. It’s being pushed against the bottom of the bucket by inertia (in this case, centrifugal force), but that bucket and your arm work against the force. They even out in the end: the water can’t move through the bucket’s bottom, it can’t escape over the lip, either, so it kind of stays in one place.

For satellites, the Earth’s gravity acts as the arm and bucket in the above example. One really simple way to understand the process is to visualize the satellite as a rocket that’s always going forward, tied with a very long chain to the center of our planet — it will just go around in circles.

What’s important here is to get the distance right. First off, you want your satellite to be outside of the planet’s atmosphere, so as to avoid air drag and keep a constant speed. But you don’t want to be too far away, because the force of gravity is inversely proportional to the squared distance between two objects. So if you double the distance between a satellite and the Earth, gravity would only pull on it one-quarter as strongly. If you triple it, it would only be one-ninth of the force. In other words, put a satellite too close to Earth and it will fall. Put it too far away, and it escapes into space.

In essence, what engineers try to do when putting a satellite in orbit is to make it fall forever. We put it up high enough that air friction is almost zero (ideally, zero). Then we push it really fast in one direction. Finally, we rely on the Earth’s gravity to pull it down while it is moving forward, so the resulting movement is a circle. Because it’s moving forward and the planet is round, it’s essentially gaining altitude constantly. But, since it’s also falling at the same time, it’s losing altitude constantly. The sweet spot is to have it escape into space just as fast as it’s falling down to Earth, all the time.

If the math is done just right and the deployment phase goes properly, these two cancel each other out, and we get an orbiting satellite. In practice, it never goes quite perfectly, which is why these devices are fitted with fuel and thrusters so they can perform tiny adjustments to their direction of motion or altitude and keep them in orbit.

A good example of what would happen in the absence of these thrusters is the Moon. Our trusty and distinctive nighttime companion is not on a stable orbit — it’s slowly escaping Earth’s gravitational pull. Due to the specifics of how the Earth’s gravitational field interacts with the Moon, our planet is ever-so-slowly accelerating it into a higher orbit. Continuing with the above example, it’s making the ‘escape into space’ force a tad more powerful than the ‘falling down to Earth’ force. As a consequence, the Moon will probably break out of orbit with Earth in the future, but we’re talking billions of years here.

Alternatively, we have (had?) the Mir space station as an example. This Russian installation ended its mission in March 2001 and was brought to a lower orbit — it was ‘deorbited‘. Here, air friction steadily slowed it down. Because of this, gravity started gaining the upper hand and Mir eventually burned up in the atmosphere while spinning around the globe, closer and closer to the surface.

The physics of how bodies in space interact is always fascinating, at least it is to me, and generally has a weird quirk to it that spices every scenario up. The idea that something can keep falling forever without actually coming closer to the ground certainly is quirky, and it fascinated me ever since I first came upon it. Later, sci-fi would bring me to concepts such as gravitational slingshots, which are very similar to what we’ve discussed here, but they actually help you go to space faster. Cool.

Our discussion so far makes this whole process sound simple, and in theory, it is. But very many bright people had to crunch some extremely complicated math to make it possible, and many still do that, in order to keep satellites orbiting over our heads. As much as falling forever sounds like magic, it’s built on countless hours of intellectual work and, in this day and age, on some very powerful computers running calculations around the clock. 

Changes in moon’s ‘wobble’ could cause record floods in 2030

High-tide flooding in Honolulu. Credit:  Hawaii Sea Grant King Tides Project.

The U.S. coastline can expect to see three to four times as many high-tide flood days each year during the 2030s. Normally, in such a situation, climate change is to blame (and truthfully, it will definitely contribute to some extent to floods in North America in the future), but this time we also have to look to the moon. According to a new study, in the mid-2030s, the moon will enter a tide-amplifying cycle that, when combined with global sea-level rise due to climate change, could cause troublesome higher-than-usual high tides.

The moon is held in place by Earth’s gravity. But just because it’s smaller — the moon only has about 1/100th the mass of Earth — that doesn’t mean that the moon doesn’t exert its own influence on Earth. The moon’s gravitational pull on the planet generates what’s called the tidal force, causing water in the oceans to bulge out on the side closest to the moon and the side farthest from the moon. These bulges are what we know as high tides.

Since the planet rotates, every region of Earth will pass through both of these bulges each day. When you’re in one of these bulges where the water wants to travel towards the moon, you experience a high tide. But when you’re outside the reach of these bulges, you experience a low tide.

It takes half a lunar day, on average 12 hours and 25 minutes, from one high tide to the next, so we have high and low tides nearly twice a day. The change from low to high tide is known as flood tide, while the change from high to low tide is called ebb tide

The tidal force causes water to bulge toward the moon and on the side opposite the moon. These bulges represent high tides. Credit: NOAA.

Since continents prevent the water in the ocean from perfectly following the moon’s pull, there will be some variation between high and low tide from place to place. It can range from almost no difference to over 16 meters (50 feet). As a result, water in the world’s oceans sloshes around like it would in an oddly shaped bathtub rather than in a smooth and even basin.

High tide (left) and low tide (right) in the Bay of Fundy in Canada. Image credit: Wikimedia Commons, Tttrung. Photo by Samuel Wantman.

Besides topography, tidal range can also be affected by the moon’s phase (when the sun and the moon are aligned, their gravitational pull combines to exert more influence on the ocean) and the wobble of the moon’s orbit.

Earth’s natural satellite has an elliptical orbit, leading to variation in the velocity at which it circles the planet and causing the “light side” to appear at slightly different angles throughout any given month. In other words, the moon “wobbles” similarly to a rocking ship at sea.

It does so in a rhythmic 18.6-year cycle. During the first half of the cycle, tidal forces are slightly suppressed, leading to lower high tides and higher low tides. During the other half of the cycle, the pattern is reversed, with higher high tides and lower low tides.

At the moment, we’re in the tide-amplifying part of the cycle. This phase will repeat itself in the mid-2030s. There’s nothing new about this wobble, first reported in 1728. But by this timeframe, scientists expect global sea levels to reach levels where higher tides can cause problems, according to a new study published in Nature Climate Change by researchers at NASA.

The researchers claim that during the next higher-than-usual high tide phase of the lunar cycle, American coastal cities could flood up to four times as often as they do now. These floods will sometimes occur in clusters lasting a month or longer, depending on the positions of the moon, Earth, and the sun.

“It’s the accumulated effect over time that will have an impact,” said Phil Thompson, an assistant professor at the University of Hawaii and the lead author of the new study.  “But if it floods 10 or 15 times a month, a business can’t keep operating with its parking lot under water. People lose their jobs because they can’t get to work. Seeping cesspools become a public health issue.”

According to the researchers, the higher sea levels amplified by the lunar cycle will cause frequent flooding in almost all U.S. coastlines, apart from far northern coastlines like Alaska.

The good news is that urban planners have ample time to prepare for the upcoming high tide floods.

“From a planning perspective, it’s important to know when we’ll see an increase,” said study co-author Ben Hamlington of NASA’s Jet Propulsion Laboratory in Southern California. “Understanding that all your events are clustered in a particular month, or you might have more severe flooding in the second half of a year than the first – that’s useful information.” A high-tide flood tool developed by Thompson already exists on the NASA team’s sea level portal, a resource for decision-makers and the general public. The flood tool will be updated in the near future with the findings from this study.

NASA says U.S. coastal cities should expect frequent high-tide floods by mid-2030, and the Moon is partly to blame

The US will see a dramatic increase in high-tide coastal flooding in the coming decade, according to NASA. This increase will be powered by the interaction between the moon’s gravitational influence (which causes tides) and higher sea levels caused by climate change.

Image credits Tim Hill.

High-tide floods are an already familiar problem in several areas of the US, mainly in cities on the Atlantic coast and a few of those dotting the Gulf coast. According to the National Oceanic and Atmospheric Administration (NOAA), more than 600 such floods occurred in the States in 2019.

But such events are likely to pick up in frequency around the mid-2030s, a new paper reports, mainly due to changes in climate — although astronomy does play a part, as well. The research was led by researchers at the NASA Sea Level Change Science Team from the University of Hawaii. Apart from warning of an increased frequency of such events in the future, the team also explains that the floods will likely occur in clusters of about a month or so at a time, depending on the relative positions of the Earth, Moon, and Sun. When our planet, the Sun, and the Moon line up in specific ways, they note, the resulting gravitational pull is likely to cause floods, especially considering the higher sea levels of the future.

Floods-to-be

“Low-lying areas near sea level are increasingly at risk and suffering due to the increased flooding, and it will only get worse,” said NASA Administrator Bill Nelson. “The combination of the Moon’s gravitational pull, rising sea levels, and climate change will continue to exacerbate coastal flooding on our coastlines and across the world. NASA’s Sea Level Change Team is providing crucial information so that we can plan, protect, and prevent damage to the environment and people’s livelihoods affected by flooding.”

The paper’s lead author Phil Thompson, an assistant professor at the University of Hawaii, explains that this process won’t be devastating due to the severity of the floods themselves, but rather, through their sheer number. Taken individually, high-tide floods involve relatively small amounts of water. “But if it floods 10 or 15 times a month, a business can’t keep operating with its parking lot under water. People lose their jobs because they can’t get to work. Seeping cesspools become a public health issue.”

The root of the issue is the Moon’s wobble. Our planet’s satellite has a regular wobble in its orbit caused by the specifics of how it rotates, how the Earth rotates, and how the two move relative to one another. This wobbling cycles every 18.6 years, and it’s a phenomenon known since the early 1700s. What changed, however, is sea level — rising seas interact with this wobble to make flooding way more likely, and way more common.

Throughout half of the cycle, the daily tide on our planet is suppressed. High tides aren’t as high as they should be, and low tides are not as low. In the other half, however, they’re amplified — higher at their highest, lower at their lowest. But since climate change is pushing sea levels up, it’s also lifting the tide higher at all times. Overall, this means that one half of the 18.6-month cycle will be counteracted, while the other will see higher high tides.

Right now, the Moon is in the tide-amplifying part of the cycle, but sea level rise has not been significant enough for it to translate into flooding across U.S. coastlines. However, by the next time this phase comes around, in the mid 2030s, the mean sea level will be higher than today. Under the Moon’s gravitational effect, we’re very likely to see frequent flooding on almost all U.S. mainland coastlines, Hawaii, and Guam, the team explains. Northern coastlines such as Alaska’s will likely not see frequent flooding in the mid-2030s, as they are rising generally due to geological processes, but they will likely suffer the same by the mid-2040s.

For the estimations, the researchers studied recordings from 89 tide gauge locations in every coastal U.S. state and territory except Alaska. Factoring in NOAA’s sea-level rise scenarios and flooding thresholds, they created a statistical model that estimates the number of times these thresholds have been exceeded annually, and how this related to the lunar wobble cycle. Other processes known to affect tides, such as El Niño events, were also factored in. Then, this model was used to project changes in flooding (defined as sea levels exceeding flooding thresholds) up to 2080.

“From a planning perspective, it’s important to know when we’ll see an increase,” said co-author Ben Hamlington from NASA’s Jet Propulsion Laboratory in Southern California, leader of NASA’s Sea Level Change Team. “Understanding that all your events are clustered in a particular month, or you might have more severe flooding in the second half of a year than the first – that’s useful information.” A high-tide flood tool developed by Thompson already exists on the NASA team’s sea level portal, a resource for decision-makers and the general public. The flood tool will be updated in the near future with the findings from this study.

We’ve found a dead star that’s about as large as the Moon, but weighs more than the Sun

Researchers report finding the smallest white dwarf — and likely, smallest star in general — we’ve ever seen. And it’s just a tad smaller than our Moon.

Artist’s rendering of a white dwarf. Image via Pixabay.

White dwarves are dead stars, the leftover cores of stars which reached the red giant stage but petered out. They’re extremely dense things, usually composed mainly of carbon and oxygen. This particular one, named ZTF J1901+1458, has a radius of approximately 1,700 kilometers — just shy of the Moon’s radius of 1,737 — and sits some 130 light-years away from us.

Despite its size, however, the dwarf has around 1.3 times the mass of the Sun.

Small but mighty

“That’s not the only very amazing characteristic of this white dwarf,” astrophysicist Ilaria Caiazzo of Caltech said June 28 in an online news conference. “It is also rapidly rotating.”

White dwarfs are typically similar in size to the Earth, which has a radius of around 6,300 kilometers. But one of their interesting properties is that they tend to be smaller the more mass they contain. This has to do with how they maintain stability. White dwarfs can’t generate the same physical processes that keep other stars from collapse, as they have no fuel to ‘burn’. Instead, their shape is maintained by the electrons in their atoms being physically pushed into one another to their limit. The tighter the squeeze, the more these electrons push back through quantum processes (electrons hate being near other electrons). So higher mass white dwarves, which have a stronger gravitational pull trying to make them collapse, need to become smaller in order to squeeze their electrons that much harder and counteract the pull.

Given its small size, then, ZTF J1901+1458 is one of the most dense objects of its kind.

It’s also quite restless, making a full spin once every seven minutes or so. The Earth makes a full rotation once every day. All this motion means that ZTF J1901+1458 produces quite the impressive magnetic field, estimated to be at least a billion times stronger than our planet’s. Needless to say, this is not a peaceful place to visit.

The stellar remnant was discovered using the Zwicky Transient Facility at Palomar Observatory in California, which scours the sky for objects with variable brightness. Given that they’re basically stellar corpses with no internal source of energy, white dwarves start out bright and incandescent but slowly cool and dim over time, eventually becoming an extinguished black dwarf.

As for how it came to be, we’re still unsure — but its mass provides a solid hint. The team’s working hypothesis is that ZTF J1901+1458 was born from the merger of two white dwarves that orbited one another and eventually merged into a single, extra-chunky, dwarfier white dwarf. This would also explain why it’s spinning so fast and why its magnetic field is so powerful.

All things considered, this merging could have easily ended badly. If ZTF J1901+1458 was more massive, it wouldn’t have been able to support its own weight and would have exploded. Finding a body so close to the edge of what’s possible will help us better understand what we’re going to run into once we eventually start trekking through space.

The paper “A highly magnetized and rapidly rotating white dwarf as small as the Moon” has been published in the journal Nature.

Chinese rover finds weird shard-shaped rock on the far side of the moon

Credit: China National Space Administration.

China’s Yutu-2 rover just turned two years old and it received a fitting birthday gift. During one of its forays on the far side of the moon, the rover came across an elongated shard that has surprised scientists.

Yutu-2 is the first man-made craft that has explored the moon’s far side. On February 6, the rover resumed operations after Chinese mission control engineers forced it into hibernation in order to preserve energy during the cold lunar nights.

Thanks to Yutu-2, we now know what the moon looks like below the surface after the rover beamed back radar images it had collected. It also sent back very valuable photos and videos of the moon’s far side that will keep scientists busy for years.

Since it arrived at the moon’s far side, Yutu-2 has also come across a number of peculiar objects. In 2019, not long after touchdown, the rover found a “gel-like” substance that turned out to be breccia (broken fragments of minerals cemented together) formed by impact melts.

Credit: China National Space Administration.

Now, Chinese scientists have reported what they describe as a ‘milestone’: an elongated shard sticking out of the lunar surface. The vast majority of lunar rocks are rounded, so the pointy rock immediately drew scientists’ attention.

Due to its shard-like shape and pronounced ridge near the rock’s edge, scientists believe that it must be geologically young since it didn’t have enough time to get rounded by weathering.

As for its formation, the most likely explanation is that it is impact ejecta from a nearby crater. Planned investigations using the rover’s visible and near-infrared imaging spectrometer may reveal more insights surrounding this strange rock’s nature.

Radio waves snap a picture of Apollo 15 landing site picture all the way from Earth

New radar image of the Apollo 15 landing site, located with respect to prominent lunar features. Credit: Sophia Dagnello, NRAO/GBO/Raytheon/AUI/NSF/USGS.

This might look like your typical space photo, but there’s more to it than meets the eye. This stunning image of the Apollo 15 landing site wasn’t taken by an optical instrument, such as a camera, but rather by a radar telescope that bounced radio waves off the surface of the moon.

In the image, we can see Hadley Rille, the meandering channel that runs across the middle. It was formed millions of years ago by collapsing lava tubes during a time when the moon was still volcanically active. The circular feature pictured is, you’ve guessed it, a crater known as Hadley C, measuring 6 kilometers (3.7 miles) in diameter.

GBT-VLBA radar image of the region where Apollo 15 landed in 1971. Credit: NRAO/GBO/Raytheon/NSF/AUI.

What’s amazing about this photo is its astonishing resolution, which can resolve objects as small as 5 meters across from 384,000 kilometers (239,000 miles) away.

Because Earth has a thick atmosphere and an active weather system, it can be challenging to image things with a normal optical telescope. For this reason, scientists typically position their telescopes at high-altitude locations, perched on a mountain. A fine example is the Atacama Large Millimeter/submillimeter Array (ALMA) telescope facility that sits on top of a 5,000m-high plateau in Chile.

But if you use radio waves, the interference is minimal. For the past two years, scientists at the National Radio Astronomy Observatory (NRAO) in the U.S. have been experimenting with radio imaging technology that can take astronomical snapshots from Earth. The fruit of their labor is the Green Bank Telescope (GBT) in West Virginia — the world’s largest fully steerable radio telescope.

This telescope is fitted with a powerful transmitter that beamed radio waves onto the Apollo 15 landing site region. The reflected waves that bounced off the lunar surface were detected by NRAO’s continent-wide Very Long Baseline Array (VLBA). This pattern was decoded in order to construct a high-resolution image of the site — and the results speak for themselves.

What’s amazing is that we’re likely seeing just the tip of the iceberg of what this kind of technology can do. The researchers plan to scale up this proof-of-concept with a much more powerful transmitter that will allow them to image small objects passing by Earth or even as far into the solar system as Jupiter’s moons.

“The planned system will be a leap forward in radar science, allowing access to never before seen features of the Solar System from right here on Earth,” said Karen O’Neil, the Green Bank Observatory site director.

China crashes Chang’e-5 spacecraft into moon after collecting first lunar samples in 45 years

China’s Chang’e 5 moon lander and ascent vehicle separate from the orbiter/return vehicle early on Monday. Credit: CCTV.

On December 1, the Chang’e-5 lander touched down on Oceanus Procellarum, a vast lunar mare on the western edge of the near side of the Moon. After the lander collected about two kilograms of lunar samples, it deployed a small version of China’s five-star red flag and then ejected the samples on an ascended vehicle to lunar orbit. After it completed its mission, Chinese engineers sent instructions that commanded the ascent vehicle to crash into the moon on Monday.

Following the successful docking of the ascent vehicle with the Chang’e-5 lunar orbit on December 5, reports from Chinese media suggested that the ascent vehicle still had a lot of fuel, which qualified it for an extended mission. However, the China Lunar Exploration Program (CLEP) took the decision to decommission the vehicle by crashing it into the moon in order to avoid producing space junk in the moon’s orbit that could impact future missions.

The impact occurred just half an hour after mission control sent commands to the Chang’e-5 ascent vehicle, instructing it to crash at 0 degrees longitude and 30 degrees south — somewhere between the ancient craters Regiomontanus and Walther in the southern highlands region.

The docking of the ascension vehicle with the Chang’e-5 orbiter was performed with an accuracy of no less than five centimeters while mission control was 380,000 kilometers away. This experience will prove extremely useful for China’s highly ambitious missions in the future, which will involve similar rendezvous and docking maneuvers for a Mars sample return mission in 2030. China also has plans for a crew mission to the moon that will also involve an ascent vehicle, orbiter, and reentry capsule.

The Chang’e-5 orbiter carrying the precious samples collected from the moon’s surface is still in lunar orbit. Chinese mission control is still waiting for the right window of opportunity to open for trans-Earth injection.

According to Chinese state media, the operation is scheduled for the next few days, most likely on Saturday, resulting in the landing of the reentry capsule at Siziwang Banner, Inner Mongolia.

If successful, Chang’e-5 will become the first mission to bring lunar samples back to Earth since the landing of the Russian spacecraft, Luna 24, on August 18, 1976. During the Apollo missions, the United States retrieved 382 kilograms of lunar rocks and soil, whereas the former Soviet Union brought over 300 grams of lunar samples back to Earth during three missions.

A Big Blue Marble. A History of Earth from Space

“As the Sun came up I was absolutely blown away by how incredibly beautiful our planet Earth is. Absolutely breathtaking. Like someone took the most brilliant blue paint and painted a mural right in front of my eyes. I knew right then and there that I would never, ever see anything as beautiful as planet Earth again.”

Scott Kelly, Former NASA Astronaut
The Blue Marble. Taken by the crew of Apollo 17 in 1972 at a distance of 29,000 km above the planet. (NASA/Apollo 17 crew)

There is a common experience shared by human beings who visit that edge of space when they turn back and look upon their home planet. In that most fleeting of moments, they see the beauty and delicacy of our homeworld. It’s clearly not a view that many of us will get to experience in person, certainly not for the foreseeable future at least.

Despite that, thanks to some incredible photography and imaging techniques we too can view Earth from space and get a sense of our place in the solar system and the wider universe. 

The term ‘Big Blue Marble’ as it applies to Earth refers to an image captured of our planet by the Apollo 17 astronauts in December 1972. The image — officially designated as AS17–148–22727 by NASA— was taken at 29 thousand kilometres above the Earth by the crew of the spacecraft as it headed to the Moon.

Turning their view back on our planet, the astronomers caught a stunning image of the Mediterranean Sea to Antarctica. The image shows the south hemisphere heavily shrouded by clouds and represents the first time that an Apollo craft had been able to capture the southern polar ice caps.

The original uncropped AS17–148–22727 from which 'the Blue Marble' is taken. (NASA/Apollo 17 crew)
The original uncropped AS17–148–22727 from which ‘the Blue Marble’ is taken. (NASA/Apollo 17 crew)

Perhaps the most extraordinary thing about AS17-148-22727 is that it wasn’t supposed to exist. The crew weren’t scheduled to take an image at that point in their journey.

The fact that the photo was snapped very much during a ‘stolen moment’ aboard the craft and during a mission that was tightly scheduled down to the minute, makes the fleeting beauty it presents even more striking, as too does the fact that no human since has travelled far enough away from the surface of the planet to take such an image.

Since being taken ‘the Blue Marble’ has rightfully become one of the most reproduced images in human history. Though the most famous image of Earth from a space-based vantage point and a rare example of the glimpse of a fully illuminated globe, AS17–148–22727 is just one of a cavalcade of stunning images of our planet taken over seven decades.

The very first of these images were captured in perhaps the most unusual and ironic of circumstances. 

The Early days of Earth Photography: Recovering from War

“Consider again that dot [Earth]. That’s here. That’s home. That’s us. On it everyone you love, everyone you know, everyone you ever heard of, every human being who ever was, lived out their lives. The aggregate of our joy and suffering, thousands of confident religions, ideologies, and economic doctrines, every hunter and forager, every hero and coward, every creator and destroyer of civilization, every king and peasant, every young couple in love, every mother and father, hopeful child, inventor and explorer, every teacher of morals, every corrupt politician, every ‘superstar,’ every ‘supreme leader,’ every saint and sinner in the history of our species lived there – on a mote of dust suspended in a sunbeam.”

Carl Sagan, Pale Blue Dot: A Vision of the Human Future in Space
The first image of Earth taken from space in 1946 (White Sands Missile Range / Applied Physics Laboratory)

During the Second World War German V2s caused untold amounts of damage upon the cities of Europe, raining death from the skies and bringing profound fear and sorrow. It’s somewhat ironic then that the scientific marvel of the first image of Earth from space was delivered by one of these fearsome rockets.

Several V2s– Vergeltungswaffe 2, the world’s first long-range guided ballistic missiles–had been reclaimed by the United States as part of Operation Paperclip. The aim, however, was to use their incredible supersonic speed not to escape radar detection, as had been the case during the war, but to escape the confines of the atmosphere.

The rockets had their explosive payloads removed from their nosecones and replaced with scientific equipment.

On 24th October 1946, experiments with the V2s would result in a tangible benefit and a legitimate scientific breakthrough. A rocket launched from the White Sands Missile Range in New Mexico, USA, would capture an image of the Earth from an altitude of 105km. Up until this point in time, the highest an image of earth that had been taken was 22km by equipment aboard a high-altitude balloon.

The image was captured by a 35mm camera in the device’s nosecone which was set to capture a picture every 1.5 seconds. These images were then dropped back to earth in a steel canister and developed.

(White Sands Missile Range / Applied Physics Laboratory)

The V2 program and the series of experiments that it birthed would help US scientists lay the groundwork for future space exploration and was reflected by similar experiments in the Soviet Union at the time. These programs and the reclamation of German technology and the scientists behind it was responsible for launching the space race of the 1950s and 1960s. And no goal or aspiration would encompass this heated scientific battle more than the desire to put a human on the Moon.

The Earth and the Moon: Picturing a Perfect Partnership

“Orbiting Earth in the spaceship, I saw how beautiful our planet is. People, let us preserve and increase this beauty, not destroy it!”

Yuri Gagarin, the first human in space (12 April 1961)
A view of the Earth from the Moon taken by NASA’s Lunar Orbiter 1 in 1966 (NASA/ LOIRP).

By 1966 when the image above was captured the space race was in full swing. The USSR had launched both Sputnik 1 & 2 into orbit in October and November 1957 respectively, with the first becoming the original Earth-orbiting satellite and the second carrying a dog named Laika into space.

This would quickly be followed by US satellites Explorer 1 carrying experimental equipment that would lead to the discovery of the Van Allen radiation belt, and the world’s first communications satellite SCORE, both in 1958. In the same year, the National Aeronautics and Space Administration (NASA) would be created to replace the National Advisory Committee on Aeronautics (NACA).

Earth rises above the Moon’s horizon as seen by Apollo 11 (NASA/ JSC)


Most significantly, in 1961 the Soviets would put the first human being into orbit. Cosmonaut Yuri Gagarin made a single orbit around the Earth at a speed of over 27 thousand kilometres per hour during his 108-minute stay in space.

Yet, it wasn’t the Soviets that captured the stunning image above of earth from the vicinity of the Moon’s surface. That honour belongs to the US craft Lunar Orbiter 1 (LU-A). The NASA spacecraft was the first US mission to orbit the Moon, its primary task was to photograph not the Earth but rather potential landing sites on the Moon for the upcoming Apollo missions.

Again, as was the case with Apollo 17’s ‘Blue Marble’, the image of Earth from space taken by Lu-A taken on August 28th 1966 by the onboard Eastman Kodak imaging system was completely unplanned.

In 1969 many of the Apollo missions themselves would capture stunning and evocative images of the Earth rising above the crest of the Moon’s surface–including the above image captured by Apollo 11 and the one below taken by Apollo 8. These ‘Earthrise’ photographs would become a popular expression of Earth’s relative isolation and vulnerability.

NASA’s Lunar Reconnaissance Orbiter (LRO) captured a unique view of Earth from the spacecraft’s vantage point in orbit around the moon on October 12, 2015. (NASA/ Goddard/ Arizona State University).

The Earth From the Surface of an Alien World

“The vast loneliness is awe-inspiring and it makes you realize just what you have back there on Earth.” 

Jim Lovell, Apollo 8 Command Module Pilot, during a live broadcast from the Moon on Christmas Eve 1968.

It’s no great surprise given our advancing exploration of space that our attention has turned to the view of Earth from other alien worlds. Even though we are still capturing amazing images from that vantage point such as the one above taken by NASA’s Lunar Reconnaissance Orbiter mission in 2015, our horizons have also broadened to a view of our homeworld from the surface of more distant worlds.

The first image ever taken of Earth from the surface of a planet beyond the Moon. It was taken by the Mars Exploration Rover Spirit (NASA/JPL/Cornell/Texas A&M)

The first image of earth taken from another planet (above) was captured by the Mars Exploration Rover Spirit on the 63rd Martian day of its mission in 2004. Earth was only visible in the image–comprised from images taken by the now silent robotic rover’s four panoramic cameras–after all the colour filters were removed.

This was followed up in January 2014 by NASA’s Curiosity Rover when it captured its first glimpse of Earth from the surface of Mars.

NASA’s Mars rover Curiosity took this photo of Earth from the surface of Mars on Jan. 31, 2014, 40 minutes after local sunset, using the left-eye camera on its mast. Inset: A zoomed-in view of the Earth and moon in the image. (NASA/JPL-Caltech/MSSS/TAMU)

Whilst Mars Exploration Rover Spirit and the Curiosity Rover images may not be the most visually spectacular in the catalogue built during seven decades of space exploration, it stands as a testament to man’s determination to explore other worlds. a determination that nows carries us beyond the solar system.


This composite image of Earth and its moon, as seen from Mars, combines the best Earth image with the best moon image from four sets of images acquired on Nov. 20, 2016, by the High Resolution Imaging Science Experiment (HiRISE) camera on NASA’s Mars Reconnaissance Orbiter. (NASA/JPL-Caltech/Univ. of Arizona)

A View on the Future

“You develop an instant global consciousness, a people orientation, an intense dissatisfaction with the state of the world, and a compulsion to do something about it. From out there on the moon, international politics look so petty. You want to grab a politician by the scruff of the neck and drag him a quarter of a million miles out and say, ‘Look at that, you son of a bitch!’ “

Edgar Mitchell, Apollo 14 astronaut and the sixth person to walk on the Moon.
Deep Space Climate Observatory (DSCOVR)

As we continue to expand our view of the Universe studying cosmic bodies further and further from our own solar system, the history of space photography reminds us that it is vital we keep a view on our own planet, too. It’s a testament to our scientific progress that the hardest element about putting together a brief article about images of Earth from space that it involved sifting through thousands of incredible pictures.

Currently, NASA’s fleet of satellites consists of many craft devoted to the observation of Earth from space. Often this observation from a cosmic vantage point has the benefit of providing perspective on the damage we are doing to our world. Not only this but NASA’s continued observation of our world allows us to better understand weather patterns and mitigate potential disasters.

Humanity has never been in a better position to understand our world and its place within the wider Universe. The view of our planet from space has shown us its fragility, vulnerability, and the lengths we must go to preserve this beautiful blue marble.

“It is crystal clear from up here that everything is finite on this little blue marble in a black space, and there is no planet B.”

Alexander Gerst, European Space Agency astronaut, to world leaders live from the ISS, December 17th 2018.

NASA wants to put a nuclear reactor on the moon by 2026

NASA has opened a most interesting call for projects. They’re looking for companies capable of building nuclear plants that can work on the moon — and from there, even further.

Not too long in the future, lunar outposts could use nuclear energy. Image credits: NASA.

So far, the farthest outpost mankind has ever built is the International Space Station. But NASA’s vision goes way beyond that. The space agency has already embarked on a project to send a human mission to the moon by 2024 in an effort named the Artemis project. Ideally, though, NASA (and other space agencies, including the European Space Agency) wants to establish a permanent scientific base on the moon.

Already, remarkable progress is being made. New research has identified potential sources of water on the moon, which would be vital for this type of mission. Meanwhile, another project is developing a way to separate lunar dust into oxygen and metals, both important raw materials. But to do anything at all, you need a lot of energy.

At first glance, renewable sources would seem excellent, but that’s not really the case. Without an atmosphere, wind energy is out of the question, and the rough, dusty surface of the moon is also unsuited for solar energy. Fossil fuels are heavy and difficult to transport, so this only leaves one realistic solution: nuclear energy.

The idea would be to create a working plant here on Earth, disassemble it, and then carry and reassemble it on the moon.

“Once the technology is proven through the demonstration, future systems could be scaled up or multiple units could be used together for long-duration missions to the moon and eventually Mars,” said Anthony Calomino, head of NASA’s nuclear technology portfolio at the Space Technology Mission Directorate.

In a sense, it’s not exactly innovative technology. Nuclear fission reactors have been working here on Earth for decades. But building the same thing for the moon, and making it as small and light as possible raises entirely new challenges. But it will all be worth it, NASA believes.

If we do manage to take nuclear energy to different celestial bodies like the moon or Mars, it would enable humanity to build an outpost on the moon — an outpost that would help us explore even further into the solar system.

“Four units, providing 10 kilowatts of electrical power each, would provide enough power to establish an outpost on the Moon or Mars. The ability to produce large amounts of electrical power on planetary surfaces using a fission surface power system would enable large-scale exploration, establishment of human outposts, and utilization of in situ resources, while allowing for the possibility of commercialization.”

In line with its current policy, NASA is looking to partner up with private companies to reduce costs. Over 22 companies have responded to the open call so far, but only a handful (Blue Origin and BWXT) have been named.

Twinkle, twinkle, little … moon? Jupiter’s icy moon Europa glows in the dark, researchers find

Europa, the frozen but ocean-filled moon that orbits Jupiter is bombarded by a relentless flux of radiation. Day in and day out, Jupiter flings electrons and other particles towards it. These particles hit the ice and salt-rich surface of Europa, creating a soup of complex interactions that produce something otherworldly: they make Europa glow in the dark.

This artistic illustration of Jupiter’s moon Europa shows how the icy surface may glow on the side facing away from the Sun (like the Earth’s moon, Europa is tidally locked so one side always faces Jupiter and one side always faces away). Variations in the glow and the color of the glow itself could reveal information about the composition of ice on Europa’s surface. Credit: NASA/JPL-Caltech

A song of ice and radiation

Cold Europa is already a hotspot of interest for astronomers. Although it is a frozen desert on the surface, astronomers believe it harbors liquid water beneath its icy crust, and based on what we know about its chemical make-up, it seems like a promising candidate for hosting life in this subsurface ocean.

But while the inside of the planed may be teeming with life (it’s probably not teeming, but you know), the surface is interesting in its own right. NASA astronomer Murthy Gudipati and colleagues recreated some of the interactions on Europa’s surface in the lab, exposing salted ice to energetic electrons as they would expect from Jupiter. They found that these interactions trigger a process called electron-stimulated luminescence. Simply put, it glows in the dark.

It’s an unusual process. You may be tricked into thinking it’s common for moons to glow by looking at our very own moon, bright on the night sky. But our moon isn’t glowing, it’s merely reflecting light from the Sun. Meanwhile, Europa truly produces its own light, even on the side that’s turned away from the Sun.

The surface of Europa is covered in cracked and ridged ice. Imge credits: NASA/JPL

This is more than just a cool factoid that researchers have found about Europa. The work presented here is important for understanding Europa’s surface chemical composition and mineralogy, which in turn affect its habitability.

“We were able to predict that this nightside ice glow could provide additional information on Europa’s surface composition. How that composition varies could give us clues about whether Europa harbors conditions suitable for life,” said JPL’s Murthy Gudipati, lead author of the work published Nov. 9 in Nature Astronomy.

“If Europa weren’t under this radiation, it would look the way our moon looks to us—dark on the shadowed side,” Gudipati adds. “But because it’s bombarded by the radiation from Jupiter, it glows in the dark.”

What science is all about

The salty compounds react differently to the radiation and emit their own unique glimmer. By analyzing these glimmers at different wavelengths, astronomers can connect them to their “signatures” and assess the chemical make-up of the moon. This came as a bit of a surprise: researchers didn’t expect to see variations in the glow itself tied to different ice compositions. It was, the researchers call it, serendipity.

“Seeing the sodium chloride brine with a significantly lower level of glow was the ‘aha’ moment that changed the course of the research,” said Fred Bateman, co-author of the paper. He helped conduct the experiment and delivered radiation beams to the ice samples at the Medical Industrial Radiation Facility at the National Institute of Standards and Technology in Maryland.

The proposed robot lander on the surface of Europa (artistic depiction) during the Clipper mission. Image credits: NASA/JPL.

So far, the researchers haven’t made any new discoveries about the chemistry of Europa. We’ll have to wait for NASA’s upcoming Europa Clipper mission, which will observe the moon’s surface over multiple flybys. These flybys (and the planned robot lander) could map Europa’s chemistry and gain insights about the sub-surface ocean (especially its salinity).

It’s uncommon for a lab experiment to be help a space mission know what to prepare for, but this is exactly what science is all about, says Gudipati.

“It’s not often that you’re in a lab and say, ‘We might find this when we get there,'” Gudipati said. “Usually it’s the other way around—you go there and find something and try to explain it in the lab. But our prediction goes back to a simple observation, and that’s what science is about.”

Europa Clipper is set to launch in the mid-2020s and it’s set to be one of the most exciting missions of the decade as it will investigate a part of the solar system that’s promising in regards to extraterrestrial life. Researchers are now reviewing the findings to see how Clipper’s scientific toolkit could detect variations in the moon’s glow.

Journal Reference: Laboratory predictions for the night-side surface ice glow of Europa, Nature Astronomy (2020). DOI: 10.1038/s41550-020-01248-1 , www.nature.com/articles/s41550-020-01248-1

NASA finds water in cold traps on the moon — and it could sustain a lunar base

We’ve suspected there was water on the moon for about a decade, but there was some room for interpretation. Well, not anymore.

“It’s actually 40,000 square kilometers,” Paul Hayne, one of the study authors, tells me, pointing out a typo in a press release. That’s 40,000 square kilometers that could host water on the moon.

The surface of the moon is pockmarked with water traps. Image credits: NASA.

The moon has a swarm of shadowy traps — traps where the sun never shines, cold enough that they could host water. It’s not the first time something like this has been speculated by researchers. In 2009, NASA scientists found water molecules in the polar regions of the moon.

But the 2009 study couldn’t really tell whether it was really (frozen) water or if there water is entrapped in lunar rocks. If this were the case, then the rock-embedded water (in a form called hydroxyl) wouldn’t really be of much use to potential moon missions. Now we know: it’s not.

As my colleague Rob points out, water has a distinct chemical signature that hydroxyl doesn’t, but it’s not always visible: you have to use the right instruments to see it. Casey Honniball and colleagues analyzed data from the Stratospheric Observatory for Infrared Astronomy (SOFIA) airborne telescope that observed the Moon at 6 micrometers (or microns) wavelengths. At this wavelength, the chemical signature of water becomes detectable, which confirmed that the 2009 study was on the money — it is indeed molecular water, not water that’s trapped in geological structures.

But this is just one of the puzzle pieces published today. In the other one, Paul Hayne and colleagues explored phenomena called “cold traps”.

Where the sun doesn’t shine

Imagine standing on the surface of the moon, near one of its poles, Hayne explains. You’d see a lot of shadows — shadows where the sun doesn’t shine, that are cold enough to preserve frozen water even without a lunar atmosphere.

“All of this area could harbor water ice, because these are regions where the temperature is so low (less than -163 °C) that ice is stable for billions of years.” There’s a lot of area that could hold water, but it’s not clear just how much there is. “However, we do not yet know how much is there.”

THe shadowed Shackleton Crater near the moon’s south pole is one location where scientists have found deposits of water ice. The ice can not only be used by lunar astronomers, but it has the potential to reveal insights about the moon’s history, (and the Earth’s) history. Image credits: NASA/Goddard Space Flight Center/Leonard David’s Inside Outer Space.

Hayne and colleagues found that cold traps could vary drastically in size, down to just 1 centimetre in diameter. The smaller ones are much more common, Hayne notes, and all traps are more common in the polar areas. where light falls at more of an angle.

“Our findings suggest that water deposits in the micro cold traps are much more geographically widespread in the polar regions,” he explains.

What this all means

The immediate significance of this discovery is practical: if there’s a lot of water on the moon, then there’s a lot of water that could be used in lumar missions — and having access to water is an excellent starting point for a prospective lunar base, or even a research station.

“This discovery should make it easier to perform extraction and utilization for both science and exploration missions in the future,” Hayne also explains.

But the fact that the moon could host water is only a part of the story; where did that water come from in the first place?

Water may have been delivered to the Moon over geological timescales by an astronomical bombardment, Haynes says. Understanding where it came from could even reveal where the water on Earth is sourced. But if we really want to figure that out, remote observations just won’t do.

“The mostly likely sources based on current understanding are: 1) comets, 2) asteroids and interplanetary dust, 3) solar wind protons, and 4) volcanic outgassing from the Moon itself. We will need to get down on the surface and analyze the ice deposits directly in order to understand which of these sources dominates. This also would shed light on the origins of Earth’s water.”

Journal References:

Water Found on the Moon’s Sunlit Surface

Using the Stratospheric Observatory for Infrared Astronomy (SOFIA) NASA researchers have made a stunning discovery regarding the Moon, finding that water is present on the natural satellite’s dayside, as well as its colder nightside. Hydrogen traces had previously been found at the lunar south pole, which experiences near-constant sunlight, but researchers did not believe this was related to water molecules.

This illustration highlights the Moon’s Clavius Crater with an illustration depicting water trapped in the lunar soil there, along with an image of NASA’s Stratospheric Observatory for Infrared Astronomy (SOFIA) that found sunlit lunar water. (Credits: NASA)
This illustration highlights the Moon’s Clavius Crater with an illustration depicting water trapped in the lunar soil there, along with an image of NASA’s Stratospheric Observatory for Infrared Astronomy (SOFIA) that found sunlit lunar water. (Credits: NASA)

At a virtual press conference researchers Paul Hertz, Astrophysics Division director at NASA Headquarters, Washington, Jacob Bleacher, chief exploration scientist for the Human Exploration and Operations Mission Directorate at NASA Headquarters, Casey Honniball, a postdoctoral fellow at NASA’s Goddard Space Flight Center, Greenbelt, Maryland, and Naseem Rangwala, project scientist for the SOFIA mission, NASA’s Ames Research Center, Silicon Valley, California, discussed the findings with journalists from across the globe.

“We had indications that H2O – the familiar water we know – might be present on the sunlit side of the Moon,” says Hertz.  “Now we know it is there. This discovery challenges our understanding of the lunar surface and raises intriguing questions about resources relevant for deep space exploration.”

The team’s results could change our fundamental understanding of Earth’s largest natural satellite, and also how water forms and survives in the depths of space.

The findings are significant as previously NASA had believed that water could only be found on the Moon’s nightside and in deep cavernous craters, where it may be hard to reach. Scientists had believed that water of the sunlit side of the Moon would be boiled away as a result of the lack of atmosphere and from constant exposure to the sun.

Casey Honniball offers two possible explanations as to how this water found itself at the lunar south pole; suggesting that it could have been delivered by solar winds, or by micrometeorite impacts.

If the later is the case it could relate to two possible mechanisms. Not only could micrometeorites deliver water to the surface, but the heat from these impacts could also fuse together two hydroxyl molecules, thus creating a water molecule. If this is the case, the water is likely to be sealed within tiny glass beads, about the size of a pencil tip created by the immense heat of impact.

If the water is locked up in these glass beads, they would provide an excellent protective measure to prevent water from being lost to space or evaporating as a result of the Moon’s harsh conditions.

Scientists using NASA’s telescope on an airplane, the Stratospheric Observatory for Infrared Astronomy, discovered water on a sunlit surface of the Moon for the first time. SOFIA is a modified Boeing 747SP aircraft that allows astronomers to study the solar system and beyond in ways that are not possible with ground-based telescopes. Molecular water, H2O, was found in Clavius Crater, one of the largest craters visible from Earth in the Moon’s southern hemisphere. This discovery indicates that water may be distributed across the lunar surface, and not limited to cold, shadowed places.
Credits: NASA/Ames Research Center

How Much Water Have NASA Found?

Previous measurements of hydrogen signals from the moon’s sunlit side had been associated with hydroxyl molecules, which at a 3-micron scale at which observations were performed, is indistinguishable from water. SOFIA’s observation was conducted at an improved 6-micron resolution, thus allowing astronomers to confirm the presence of water.

“Prior to the SOFIA observations, we knew there was some kind of hydration,” says Honniball, the lead author who published the results from her graduate thesis work at the University of Hawaii at Mānoa in Honolulu. “But we didn’t know how much, if any, was actually water molecules – like we drink every day – or something more like drain cleaner.

“Water has a distinct chemical fingerprint at 6 microns that hydroxyl does not have.”

Naseem Rangwala points out the amounts of water found, equivalent to roughly a 12oz bottle of water in a cubic meter, is extremely spread out.

Whilst the observations are only of the Moon’s surface, if the water is contained in glass beads then it is expected that these beads could find their way deeper beneath the lunar surface.

SOFIA will now conduct follow-up observations looking for water in additional sunlit locations and during different lunar phases to learn more about how the water is produced, stored, and moved across the Moon. 

SOFIA–So Good

SOFIA is the world’s largest airborne observatory, a modified 747 that cruises high in the Earth’s stratosphere. From an altitude of 38,000 — 40,000 feet SOFIA’s onboard 2.7-meter (106-inch) reflecting telescope is able to capture a clear view of the Universe and objects in the solar system in the infrared spectrum, untroubled by the obscuring effect of 99% of the atmosphere’s water vapour. It is this unobscured view that has allowed it to capture data that led to this astounding new discovery about water on the Moon.

SOFIA-- here seen soaring over the snow-covered Sierra Nevada mountains with its telescope door open during a test flight--has allowed NASA to make a major new moon discovery. SOFIA is a modified Boeing 747SP aircraft. (NASA/Jim Ross)
SOFIA– here seen soaring over the snow-covered Sierra Nevada mountains with its telescope door open during a test flight–has allowed NASA to make a major new moon discovery. SOFIA is a modified Boeing 747SP aircraft. (NASA/Jim Ross)

SOFIA’s main purpose is to observe the Universe in the infrared spectrum, spotting objects and events that aren’t observable in visible light. The fact that it is mounted aboard a modified 747 means it can make observations from any point on Earth, a feature that has made it particularly useful for spotting transient events. This includes eclipse–like occurrences of Pluto, Titan–a moon of Saturn, and MU69–a Kuiper belt object also known as Arrokoth, which earned the nickname the ‘space snowman’ due to its bowling pin-like shape.

What is astounding about SOFIA’s observation is that it was made during a test of the telescope as the renovated 747 flew over the Nevada Desert on its way back to its home base in California. The telescope itself isn’t usually used to view relatively bright objects such as the Moon. Instead, it would usually be used to observed dim objects such as black holes, star clusters, and distant galaxies.

“It was, in fact, the first time SOFIA has looked at the Moon, and we weren’t even completely sure if we would get reliable data, but questions about the Moon’s water compelled us to try,” says Rangwala, SOFIA’s project scientist at NASA’s Ames Research Center in California’s Silicon Valley. “It’s incredible that this discovery came out of what was essentially a test, and now that we know we can do this, we’re planning more flights to do more observations.”


Water, Water, Everywhere. But is there a drop to drink?

This new discovery contributes to NASA’s efforts to learn about more about the Moon, in the process supporting its goal of deep space exploration. The big question is how accessible is this water and can it be used by a future mission?

In this multi-temporal illumination map of the lunar south pole, where the team has discovered the telltale fingerprint of water molecules. Shackleton crater (19 km diameter) is in the centre, the south pole is located approximately at 9 o’clock on its rim. The map was created from images from the camera aboard the Lunar Reconnaissance Orbiter.
Credits: NASA/GSFC/Arizona State University


The researchers are clear that answering many of these remaining questions will require getting down to the surface of the Moon The data collected by SOFIA will be of use to these surface mission, particularly for the future NASA mission  Volatiles Investigating Polar Exploration Rover (VIPER). VIPER will take to the surface of the Moon to create a water resource map of its surface, which can then be used by future missions.

“Water is a valuable resource, for both scientific purposes and for use by our explorers,” explains Bleacher. “If we can use the resources at the Moon, then we can carry less water and more equipment to help enable new scientific discoveries.”

If water can be mined from the Moon, it could fulfil a variety of use, including the synthesis of oxygen for astronauts, and even the creation of fuel. Understanding what form the water is in is key to understanding how to extract it.

“Finding water that is easier to reach is important to us,” says Bleacher. “If it is locked up in glass beads it may take more energy to retrieve than if it locked up in the soil.” That means NASA will be looking to discover what state the water is in.

All this comes ahead of NASA’s 2024 Artemis program which will see the first woman and the next man sent to the lunar surface. This will be in preparation for NASA’s next major goal, human exploration of Mars, which could begin as early as the 2030s.

In addition to these practical applications for future space exploration, a deeper understanding of the Moon enables astronomers, cosmologists, and astrophysicists to piece together a better picture of the broader history of the inner solar system and the possibility of water existing deeper in space.

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4G on the Moon? Yes! NASA and Nokia are already working on it

In a bit to solve internet connectivity issues in space, NASA has partnered with Nokia to set up a 4G network on the Moon, as part of the Tipping Point project. The plan is to first build a 4G network, and eventually transition to 5G, just like on Earth. It will be the first 4G communication system in space.

Credit Flickr Osde8Info

NASA awarded Nokia $14.1 million to deploy the cellular network on the Moon. The grant is part of $370 million worth of contracts for lunar surface research missions. Most of the funds were given to large space companies such as SpaceX and United Launch Alliance to perfect techniques to make and handle rocket propellant in space.

The project will have to move fast to stay in line with NASA’s goal to have astronauts working at a lunar base by 2028.

“We need power systems that can last a long time on the surface of the moon, and we need habitation capability on the surface,” NASA Administrator Jim Bridenstine said in a statement.

Back in 2018, Nokia and British firm Vodafone had announced their goal for a moon mission. They intended to launch a lander and rover built by Audi, utilizing a SpaceX rocket. They would set down near the Apollo 17 landing site and examine the Luna Roving vehicle astronauts left behind in 1972.

The launch never took place but the new contract with NASA brings Nokia’s plans for moon projects to life. The upcoming 4G network could allow for surface communications at greater distances, increased speeds, and provide more reliability than current standards, NASA explains. This means communication between lunar landers, rovers, habitats, and astronauts would be possible thanks to the service, said Jim Reuter, associate administrator for NASA’s Space Technology Mission Directorate. Nokia will look at how terrestrial technology could be modified for the lunar environment, he adds.

The moon’s cellular network will operate during lunar landings and launches. At the same time, it will be designed to tolerate the particularities on the lunar surface such as radiation, extreme temperature, and vacuum.

The network will allow astronauts to control lunar rovers, stream high-definition videos, transmit data, and have real-time navigation of the lunar geography. While 4G networks on Earth need big cell towers with power generations, Nokia has created small cell technology that is much easier to pack into a rocket ship.

Other technologies funded by NASA include demonstrations of lunar surface power generation and energy storage. Intuitive Machines will develop a hopping robot that could launch and carry small packages from one lunar site to another, while Alpha Space will create a small laboratory that could land on the moon’s surface.

How on Earth did we start using “once in a blue moon”?

You’ve heard it, I’ve heard it, but not many people we know have actually seen a blue moon — so what gives?

Am image of the moon captured through a blue filter.
Image credits steviep187 / Flickr.

“Once in a blue moon” refers to events that only happen very rarely, but it’s a tricky idiom. It doesn’t refer to a moon that’s actually blue, although it can appear to be that color under certain conditions and that probably shaped the saying.

A blue moon is a real occurrence and, you might be surprised to hear, isn’t actually that rare or unpredictable. Blue moons are ‘extra’ full moons of the regular gray color that pop up every two or three years due to misalignment in the lunar and solar circle. But the phrase was first used to refer to something being absurd — like someone arguing that the moon is blue.

So let’s take a look at both halves of this idiom and see why they came to represent the quintessential rare occurrence.

The literal blue moon

Image credits Bobby Jones.

The moon can naturally appear blue or light-blue in the sky. It’s a rare event caused by the presence of dust or smoke particles in the atmosphere at night which alter the way light is diffracted in the atmosphere. If these particles are of the right size, they can scatter the red part of the light spectrum, leaving the rest untouched.

Because visible light spans from red (low-energy) to blue (high-energy), this scattering makes everything take on a blue tint. Since the moon is a white-ish gray on a dark background, this effect causes it to look blue.

This type of blue moon is probably what spawned the idiom. It’s very rare and very unpredictable, as its appearance relies directly on phenomena such as massive wildfires or volcanic eruptions. The fact that it’s entirely dependent on local phenomena also means blue moons are only visible from relatively small areas at a time, not globally — which compounds their rarity.

Some events that led to blue moons include forest fires in Canada, and the eruptions of Mount St. Helens in 1980 and the El Chichón volcano in Mexico in 1983. The eruption of Krakatoa in 1883 (one of the largest in history) reportedly caused blue moons for nearly two years.

A pretty exciting implication of the mechanism that spawns blue moons is a purple sun. In 1950, as huge fires swept the bogs of Alberta, Canada billowing with smoke, leading to sightings of blue moons from the US to England the following night. Two days later, reports of an indigo sun peering through the smoky skies also started to surface.

File:Blood moon 73.jpg
A blood moon.
Image credits Andrey73RUS / Wikimedia.

So why don’t all volcanic eruptions and wildfires turn the moon blue? Well, the size of ash or oil/tar particles they generate is very important. These have to be wider than the wavelength of red light, which is 0.7 micrometers, to block these rays. At the same time, very few to no particles of smaller sizes should be present, as these would help scatter other colors and destroy the overall effect.

Naturally-occurring ash tends to be a mix of particles of various sizes, with most being smaller than the above threshold. Since smaller particles preferentially scatter (i.e. remove) light towards the high end of the spectrum (blue), natural ash clouds typically give everything a shade of red. Red or blood moons are thus a much more common occurrence than blue moons.

The figurative blue moon

Traditionally a blue moon is an additional full moon that appears every 2 and a half years or so, according to NASA. In recent times it has also come to denote the second full moon to appear within a single calendar month in popular use.

This stems from the way lunar and solar cycles relate to one another. There are 29.5 days between full moons, the agency goes on to explain, so each year will have roughly 12.3 full moons. Another implication of this is that 28-days-long February can’t ever have a blue moon.

Both uses of the phrase are considered valid today.

Over time, the idiom turned from meaning that something is impossible to “never” — think along the lines of “I’ll help you when the pigs fly”.

“The definition of a Blue Moon [as] ‘the second full moon in a calendar month,’ is a curious bit of modern folklore. How it emerged is a long story involving old almanacs, a mistake in Sky and Telescope magazine, and the board game Trivial Pursuit,” wrote Dr. Tony Phillips for NASA.

One of the almanacs Dr. Phillips mentions is the Maine Farmer’s Almanac, more specifically its August 1937 issue. The publication followed certain conventions about how to name each moon depending on the time of year. The first full moon of spring for example was called the Egg Moon, Easter Moon, or Paschal Moon, and had to fall within the week before Easter. If a particular season had four moons, the extra one was called a Blue Moon to maintain the naming conventions.

The definition of the blue moon as being the second full month in a single month came, according to Space, from a mistaken interpretation of the term which was popularized by a nationally syndicated radio program in 1980.

Rarer than Blue Moons are double Blue Moons — when the same calendar year gets two of these events. They’re much rarer, only occurring about 3-5 times every hundred years or so; the next double blue moons are expected in 2037. As for a single blue moon, the next one is expected on October 31, 2020.

NASA plans to set a telescope on the far side of the Moon

There are many telescopes on Earth and in space, providing us with important information and carrying out different research projects. So why not set up one on the moon, with craters in lieu of a telescope dish?

Credit NASA

The space agency gave a new round of grants for its favorite innovative space projects and one is a plan to fit a 1 kilometer (3,281 foot) radio telescope inside a crater on the far side of the Moon.

The moon telescope project is one of 23 concepts that received part of a $7 million investment. The Phase I award consists of $125,000 to fund a nine-month study of the idea. Other concepts include investigating solar sails, lunar landing pads, and a robotic explorer for Saturn’s moon Enceladus.

NASA pointed out that these projects will mostly require a decade or more of technology development, and that they are not official NASA missions. These fascinating ideas are worthy of deeper investigation, though, and could one day move from concept to reality.

The Lunar Crater Radio Telescope (LCRT) would be able to measure wavelengths and frequencies that can’t be detected from Earth, working unobstructed by the ionosphere or the various other bits of radio noise surrounding our planet.

“LCRT could enable tremendous scientific discoveries in the field of cosmology by observing the early universe in the 10–50m wavelength band (6–30MHz frequency band), which has not been explored by humans to date,” writes robotics technologist Saptarshi Bandyopadhyay, who pitched the proposal.

Bandyopadhyay’s proposal lists the benefits of locating a telescope on the far side of the moon, including that “the moon acts as a physical shield that isolates the lunar-surface telescope from radio interferences/noises from Earth-based sources, ionosphere, Earth-orbiting satellites, and sun’s radio-noise during the lunar night.”

According to the proposal, moon rovers would pull out a wire mesh some 1 kilometer across, inside a lunar crater than could be up to 5 kilometers (3.1 miles) in diameter. A suspended receiver in the center of the crater would complete the system.

Everything could be automated without any human operators, which would, in turn, mean a lighter and less expensive payload for the project to literally get off the ground. But this is still at the very early stage of planning, and it’s not clear yet exactly which crater would be used for the job.

“Building the largest filled-aperture radio telescope in the Solar System on the far side of the Moon is bound to create a lot of public excitement,” Bandyopadhyay and his colleagues write in a 2018 paper on the idea. “This concept would unlock the potential for ground-breaking scientific discoveries in radio astronomy.”

Trump gives signal for moon mining with new decree

With much of the world currently dealing with the coronavirus pandemic, US President Donald Trump is also looking at the moon.

Credit NASA

Trump signed an executive order called “Encouraging International Support for the Recovery and Use of Space Resources,” which reaffirms that Americans should have the right to engage in commercial exploration, recovery, and use of resources in outer space.

“This executive order establishes U.S. policy toward the recovery and use of space resources, such as water and certain minerals, in order to encourage the commercial development of space,” Scott Pace, executive secretary of the U.S. National Space Council, said in a statement.

The order had been in the works for about a year and reflects the US’ long-held pro-business approach when dealing with space resources. In 1979, the country refused to sign the Moon Treaty that would stipulate non-scientific use of space resources to be governed by an international regulatory framework.

At the same time, in 2015, Congress passed a law that allowed U.S. companies and citizens to freely use lunar and asteroid resources. With Trump’s new executive order, the U.S. now possesses a clearer vision for future off-Earth mining, without the requirement for further international treaties or agreements.

The order comes during a push for lunar exploration. Last year NASA unveiled the Artemis program’s mission to send astronauts to the moon by 2024. A part of the operation would entail establishing a sustainable lunar outpost by 2028, fueled by tapping into lunar resources like water ice that is thought to be plentiful on craters.

Nevertheless, the moon is not the final destination for NASA’s ambitions. Mars is also in line and to reach that goal the Artemis program will help NASA and its partners learn how to support astronauts in deep space with limited resources for long periods of time. NASA, though, will have strong competition from Elon Musk’s SpaceX.

The question of which laws apply (including property laws and border agreements) once you leave the surface of the Earth is a complex one; even if it weren’t, many laws and rules on the topic were written or conceived of during a very different space age and various forms of Cold War.

As it stands, there is very little in the way of official legal status for materials harvested on the Moon. Which authorities on Earth are going to arbitrate disagreements? How will we prevent the lunar surface from being disfigured by a commercial mining operation?

To that end, the U.S. will “seek to negotiate joint statements and bilateral and multilateral arrangements with foreign states regarding safe and sustainable operations for the public and private recovery and use of space resources,” the executive order reads. Nevertheless, in seeking international support, the U.S may draw on legal precedents and examples from other domains to promote the recovery and use of space resources.

“American industry and the industries of like-minded countries will benefit from the establishment of stable international practices,” the order reads.