Tag Archives: esa

As long as we have known that the sun is just another star, we have dreamed of other worlds. Thanks to the exoplanet hunter's toolkit, we can now do more than dream.

The Exoplanet Hunter’s Toolkit: the science of searching for other worlds

We have all, at some point, stared at the stars and dreamed lazily of other worlds, but, fortunately, for many of us, dreaming alone was not enough. These people set about building a toolkit stocked with instruments and techniques to find planets outside our solar system — exoplanets. In turn, these tools help us better understand our place in the Universe. 

An artist’s impression of 51 Pegasi b — not the first exoplanet to be discovered, but the most important (ESO/L. Benassi)

In October the Nobel Committee awarded the 2019 Nobel Prize in Physics to Michel Mayor, Professor at the Observatory of the Faculty of Science of the University of Geneva (UNIGE), Switzerland, and his doctoral student Didier Queloz for their discovery of 51 Pegasi b in 1995 — which marked the first discovery of an exoplanet orbiting a Sun-like star. The award marked the first time that exoplanet research has scooped what is, arguably, the most prestigious prize in science. Quite fitting as even though 51 Pegasi b was not the first exoplanet to be discovered — that honour goes to Astronomers Aleksander Wolszczan and Dale Frail who discovered an exoplanet around a neutron star in 1992 — it was Mayor and Queloz’s breakthrough that really spurred on the science of exoplanet investigation. 

As extraordinary as it sounds, before the 1990s, it wasn’t entirely certain that other stars actually possessed planets of their own. Whilst there was technically no reason to suspect that the solar system was unique, the 1980s had proved a frustrating time for exoplanet hunters. By the turn of that decade, many potential candidates had come and gone evading positive confirmation. 

Despite early setbacks, since 1995, the catalogue of exoplanets has soared, with over 4,000 examples now in NASA’s catalogue. And with technology only improving, that collection is set to soar. This animation and sonification from SystemSounds is a stunning representation of how the field has exploded since the 1990s. Created by SYSTEM Sounds (Matt Russo, Andrew Santaguida)

Created by SYSTEM Sounds (Matt Russo, Andrew Santaguida)

We are becoming so confident in the discovery of exoplanets, that we are now turning our attention to much more detailed examinations of previously discovered examples. For example, many researchers are now focusing on the investigation of exoplanet atmospheres, attempting to discover if they contain traces of chemicals such as carbon monoxide and other organic and complex molecules, and, of course, water. Should these elements be observed it constitutes a clue, a tiny hint, that life may not be unique to our planet. 

Thus far, searches for exoplanets have been more effective in finding gas giants, planets similar to Jupiter. But new advances such as the James Webb Space Telescope and the Extremely Large Telescope have researchers salivating at the idea of finding and examining smaller, rocky planets. Planets just like Earth. And of course, the discovery of the Trappist-1 system — containing seven Earth-like rocky planets, three in the so-called ‘habitable zone’ capable of harbouring liquid water — has shown that these planets are definitely out there waiting for us to find them. 

An artist’s impression of the Trappist-1 system — 7 Earth-like planets orbiting a red dwarf star (NASA)

As such, exoplanet research stands on the cusp of providing an answer to the question we have all pondered at some point whilst staring at the stars, are we alone in the universe?

Of course, the fact that it took so many years of fruitless searching to begin to successfully spot exoplanets illustrates, these blighters are extremely difficult to observe. This means that astronomers have had to develop extremely precise and sensitive methods of exoplanet detection. These techniques are numerous, each with its own strengths and weaknesses. 

Wobbly Stars

It goes without saying that before we spotted the first exoplanet, our experience of observing other planets was restricted to our neighbours in the solar system. This was done exclusively through direct imaging, but this technique becomes much more difficult as the distance to an object increases. 

Spotting planets in our solar system is possible with direct imaging techniques, for exoplanets, much craftier methods are required (NASA)

The hindrances imposed on direct imaging increase exponentially when we consider the effect of attempting to spot a dim object next to a much bright one — exactly the scenario faced when attempting to spot a distant planet orbiting its parent star. But, this proximity to an extremely bright object is not always a hindrance to exoplanet detection. In fact, many methods of spotting these planets absolutely depend on it. If a dim object can have an effect of the extremely bright object — then the ability to observe this bright object is a benefit.

This interference arises from the fact that stars with planets orbiting them demonstrate a ‘wobble’ in their motion. This arises from the fact, that despite common belief, planets don’t actually orbit stars. In fact, planets and stars orbit a mutual centre of mass— or barycentre —its location based on the masses of the planets and stars involved. As the usual set-up of a planetary system involves a star that is tremendously more massive than its planets, this mutual point of orbit is usually closer to the star centre of mass — often within the star’s surface.

This huge disparity in mass means that this ‘wobble’ is tiny. As an example, consider our own solar system. As the Sun constitutes more than 99.9% of the total mass of the solar system, the barycentre for our planetary system is located very close to our star’s centre of mass. The most significant gravitational influence on the Sun arises as a result of the solar system’s most mass planet — Jupiter. 

Rather than orbiting the Sun, both Jupiter and the Sun orbit a mutual centre of mass. This centre of mass is closer to the surface of the Sun and thus results in a slight ‘wobble’ in the star’s motion. This wobble can be used by astronomers to infer the presence of a planet. (Robert Lea) 

Let’s imagine, for simplicity’s sake, that Jupiter is the only planet orbiting the Sun. An observer viewing this reduced solar system and Jupiter’s 12-year orbit from the nearest planetary system — Alpha Centauri, 4.4 light-years away — would see the Sun as a mere point of light. The shift in its position caused by Jupiter would be just 3.7 milliarcseconds. To put this shift into perspective, consider that one pixel in an image from the Advanced Camera for Surveys aboard the Hubble Space Telescope represents 50 milliarcseconds — one pixel! Thus you can see, this ‘wobble’ caused by Jupiter is a tiny, barely perceptible amount of movement, less than 1/10 of a pixel from the nearest star!

Two further things to consider in this hypothetical situation, Jupiter is the most massive planet in the solar system, the wobble caused by Earth viewed from the same position would be smaller by a factor of at least 300. Also, many of the exoplanets that we are attempting to spot are much further afield than 4.4 light-years. That means that any method using this wobble must be incredibly sensitive and precise. Incredibly, despite this tiny effect, the wobble has spawned several methods of exoplanet detection. 

The astrometry method depends on measuring the ‘wobble’ of a star caused by a planet in orbit around it. (ESA)

One of these methods is astrometry — very effective for detailing high-mass planets in wide orbits around relatively low-mass stars, and thus not well suited to tracking down Earth-like, rocky planets. For an indirect observation method, astrometry is pretty good at pinning down characteristics like mass, and orbital period, shape and width. Unfortunately, it isn’t great at actually identifying planets. 

Thankfully there are other indirect techniques that have helped astronomers help find exoplanets — one of which combines a star’s ‘wobble’ with a phenomenon familiar to drivers and pedestrians everywhere.  

Sirens, soundwaves and stars. The Doppler Wobble

I’m sure everyone reading this has been in a situation in which an ambulance with sirens blaring has raced towards them, passed their position and continued on its journey. You’ll have likely noticed that as the vehicle approaches the sound of its siren is higher pitched, switching to a lower pitch as it moves away.

This is because as the soundwaves are emitted by the approaching ambulance they are compressed and shorter wavelength sound waves mean a higher-pitched sound. As the siren recedes, the soundwaves are stretched out — resulting in a lower pitch. 

The Doppler effect as it applies to soundwaves. The soundwaves from the approaching ambulance are compressed — resulting in a higher pitch. The soundwaves as the ambulance recedes are expanded, and thus lower-pitched. (Robert Lea)

This is the Doppler effect, and the key thing for astronomers is, it applies to any kind of wave emitted by a moving object — even light which propagates as a wave. Just as the wavelengths of soundwaves correspond to different pitches, the wavelengths of light correspond to different colours. Longer wavelengths producing a reddening, shorter wavelengths produce bluer light. This is referred to as redshift and blueshift— a crucial phenomenon in astronomy. 

Instead of an ambulance, let’s think about a star moving towards us, as the light waves emitted are compressed — causing the light signature of the star to be shifted towards the blue end of the spectrum. As the star moves away, the light is stretched out again — shifting the light signature towards the red end of the electromagnetic spectrum. 

The Doppler Effect as it would appear for light-waves emitted by a star. I shouldn’t have to say, but nothing is to scale in this image! (Robert Lea)

If this is the case, why do the lights atop the ambulance as it recedes not appear redder than they were on their approach? This is because the amount of red and blue shift is determined by an object’s speed divided by the speed of light c. As c is so large, an object would have to be moving at tremendous speeds to result in a significant enough change in colour for us to notice. 

You might be wondering how exactly scientists can tell that a star’s signature has shifted towards either end of the electromagnetic spectrum. This is because stars don’t emit light in a constant ‘smear’ across the spectrum. There are notable dark bars where light is not emitted — referred to as the absorption spectrum. It is by tracing the shift of these bars that researchers can see if a star is wobbling and by how much, thus inferring the presence of exoplanets. 

The light signature of a star contains dark absorption lines. These lines not only tell us what elements the star is composed of but also, by tracking the shift in these lines we can infer the presence of an orbiting planet. (Lund Observatory)

Of course, you may well have noticed a flaw with this technique. It’s only useful in detecting exoplanets that are causing their star to wobble towards and away from Earth. This gives rise to the method’s alternative name — the radial-velocity method. In addition to this blind-spot in glimpsing planets moving perpendicular to Earth, the Doppler-wobble technique can also only tell us what a planet’s minimum mass is. 

But, knowledge of the light signature of a star gives rise to another tool in the exoplanet hunter’s arsenal, one which depends on planets crossing — or transiting — their parent star. The photometry technique. 

Don’t cross me!

The photometry technique measures the dip in brightness of a star caused as a planet crosses in front of it, thus allowing us to infer the presence of an exoplanet and even collect details about a few of its characteristics. The method clearly requires searching for rare eclipse events where a planet blocks some of its parent star’s light. 

An illustration of the photometry technique which relies on a planet crossing its parent star, blocking some of the light it emits (NASA)

You may be unsurprised to learn that like the other methods detailed above, the photometry technique has to be incredibly sensitive. In this case, that is because the disparity in size between a star and a planet orbiting it is so huge in the star’s favour that the light obscured by this transit is minuscule. 

To illustrate this, take a look at this image of Mercury transiting the Sun seen from within the solar system. 

This speck, highlighted below, is Mercury. Now imagining the tiny fraction of light this would have obscured. When you’ve done that, imagine viewing this scene from millions of light-years away!

Returning to the example of Jupiter, the largest planet in our solar system, when it transits the Sun it blocks just 1% of the star’s light — making the Sun appear 1% fainter for a period of 12 hours. As small as it is, in comparison to the phenomena exploited by the two methods above this effect is massive.

And again, like its fellow methods of exoplanet detection, the photometric technique has significant limitations that define the situations in which it can be employed. Many planets don’t transit their parent stars and those that do have to be orientated ‘just right’ for the photometry method to work. Also, transits that do occur are incredibly brief, so it takes a lot of good fortune to catch one. That means that the vast majority of exoplanets that we believe exist out there in the depths of space can’t be spotted by this method. 

The Earth’s atmosphere and the ‘twinkling effect’ it has on stars is also a major hindrance to the photometry method. This results in its reliance on space-based telescopes. By taking the atmosphere out of the equation, it is possible to not just improve the precision of our measurements but also allows for the continuous monitoring of a star’s brightness without the agony of something as mundane as a rainy-day ruining data.

The future of exoplanet research is extremely bright

With all the limits and drawbacks I’ve listed it may seem like searching for exoplanets is something of a hopeless task, like searching for a needle in a haystack. Except there are 100 billion ‘haystacks’ or stars outside of our analogy in each galaxy. Clearly its a tribute to our advances in science that we have found 4000 or so ‘needles’ thus far.

The astrometry technique, the first tool we examined in the exoplanet hunter’s toolkit isn’t particularly useful, but the second, the doppler technique has been a real boon. It kickstarted exoplanet-hunting as a viable scientific field in the ’90s and provided the majority of discoveries right up into the 2000s. Despite this, its the transit technique — photometry — the last piece of equipment that we turned over, that holds the most promise for the future.

It was a slow starter for sure, reaching maturity much later than the previous two methods mentioned. But, as the use of automated and space-based telescopes has become more prevalent, the ability to keep thousands of stars under constant observation is making the photometry technique the exoplanet-hunting tool that promises to push the boundaries of our understanding of planets elsewhere in the universe. 

As our catalogue of exoplanets expands, researchers also now begin to look beyond just spotting these other worlds. The CHEOPS telescope will launch this week (17/12/19) with its mission to spot exoplanets close-by that warrant further investigation. And it is the James Webb Space Telescope, launching in 2021, that will really delve into these selected planets.

The future of exoplanet hunting. Clockwise from top: The James Webb Space Telescope, the Extremely Large Telescope and the CHEOPS telescope.

Researchers will then use some of the methods I’ve listed above to examine the atmospheres of these planets, a ‘deep-dive’ that would have seemed like little more than a pipe-dream in 1995 when Michel Mayor and Didier Queloz spotted 51 Pegasi b. 

Exoplanet research, in many ways, represents one of the ultimate expressions of the drive to perform science. For its pioneers, the men and women that stocked our toolkit, it simply wasn’t enough to lie back staring at the stars, dreaming of other worlds. 

The rocket carrying CHEOPS splits depositing its cargo into a low-Earth orbit. (ESA)

New European exoplanet-hunting telescope launches into space

After an initial setback yesterday (17/12/19) due to a software error, the European Space Agency’s (ESA) CHaracterising ExOPlanets Satellite — or CHEOPS — telescope has finally launched from the European Spaceport in Kourou, French Guiana.

Blast off: CHEOPS begins its journey to space (NASA)

CHEOPS was aboard a Russian Soyuz-Fregat rocket which blasted off at 9:54 am European time. The Rocket will take approximately 145 minutes to place the CHEOPS unit into a rare pole to pole low-Earth orbit. 

The telescope hitched a ride with an Italian radar satellite, the rocket’s primary payload. 

CHEOPS being loaded aboard its method of transport (ESA)

CHEOPS is the result of a collaboration between 11 member countries within the ESA, with Switzerland taking the lead on the project. Two of the country’s leading Universities — the University of Geneva and the University Bern — worked together to equip CHEOPS with a state of the art photometer.

This powerful device will measure changes in the light emitted by nearby stars as planets pass by — or transit — them. This examination reveals many details about a planet’s characteristics, its diameter, and details of its atmosphere in particular. 

Another type of lift-off (ESA)

By combining a precise measurement of diameter with a measurement of mass, collected by an alternative method, researchers will then be able to determine a planet’s density. This, in turn, can lead to them deducing its composition and internal structure. 

CHEOPS was completed in a short time with an extremely limited budget of around 50-million Euros.

“CHEOPS is the first S-class mission for ESA, meaning it has a small budget and a short timeline to completion,” explains Kate Issak, an ESA/CHEOPS project researcher. “Because of this, it is necessary for CHEOPS to build on existing technology.”

CHEOPS: Informed by the past, informing the future

The project is acting as a kind of ‘middle-man’ between existing exoplanet knowledge and future investigations. It is directed to perform follow-up investigations on 400–500 ‘targets’ found by NASA planet-hunter Transiting Exoplanet Survey Satellite (Tess) and its predecessor, the Kepler observatory. Said targets will occupy a size-range of approximately Earth-Neptune.

Reaching new heights (ESA)

This mission then fits in with the launch of the James Webb Telescope in 2021 and further investigation methods such as the Extremely Large Telescope array in the Chilean desert, set to begin operations in 2026. It will do this by narrowing down its initial targets to a smaller set of ‘golden targets’. Thus, meaning its investigation should help researchers pinpoint exactly what planets in close proximity to Earth are worthy of follow-up investigation. 

“It’s very classic in astronomy that you use a small telescope ‘to identify’, and then a bigger telescope ‘to understand’ — and that’s exactly the kind of process we plan to do,” explains Didier Queloz, who acted as chair of the Cheops science team. “Cheops will now pre-select the very best of the best candidates to apply to extraordinary equipment like very big telescopes on the ground and JWST. This is the chain we will operate.”

Queloz certainly has pedigree when it comes to exoplanets. The astrophysics professor was jointly awarded the 2019 Nobel Prize in Physics for the discovery of the first exoplanet orbiting a Sun-like star with Michel Mayor. 

The first task of the science team operating the satellite, based out of the University of Bern, will be to open the protective doors over the 30 cm aperture telescope — thus, allowing CHEOPS to take its first glimpse of the universe. 

CHEOPS launch postponed due to ‘Software Error’

The scheduled launch of the European Space Agency’s (ESA) Characterizing Exoplanets Satellite or CHEOPS telescope, set to usher in a new era of exoplanet research was cancelled today.

Credit: ESA.

The launch, which was set to take place at 12:54 am local time (roughly 4am ET) from the spaceport in Kourou, French Guiana was called-off due to what the University of Bern is calling a software error. The institution was set to live stream the event. 

The launch has been rescheduled and is expected to take place within the next 24 to 48 hours. The official revised launch time and date will be announced at 6:00pm (ET). 

CHEOPS is loaded aboard a Russian Soyuz-FG, which will place it in a low-Earth orbit. The procedure — which will take around 145 minutes to complete — will result in CHEOPS taking a rare pole-to-pole orbit. 

The CHEOPS mission is designed to observe exoplanets in relatively close proximity to Earth. The aim of this is to select viable targets for future investigation by the next major development in both the fields of astronomy and exoplanet research — the James Webb Telescope, set to launch in 2021. 

It is hoped that by using a combination of these instruments, researchers will finally be able to uncover characteristics of rocky exoplanets, which has been tricky up until now. This will include discovering if such bodies can maintain atmospheres and deduce the chemical compositions of these atmospheres.

It is likely that when the launch does occur, live coverage will be provided by the ESA on its website. 

An artist's impression of the CHEOPS telescope--the ESA's first S-Class project which will search for suitable exoplanets for future investigations (ESA)

Exoplanet telescope CHEOPS gears up for launch day

An artist's impression of the CHEOPS telescope--the ESA's first S-Class project which will search for suitable exoplanets for future investigations (ESA)
An artist’s impression of the CHEOPS telescope–the ESA’s first S-Class project which will search for suitable exoplanets for future investigations (ESA)

The European Space Agency’s (ESA) space telescope CHEOPS (CHaracterising ExOPlanet Satellite) begins its journey into space aboard the Soyuz rocket on December 17th. In preparation for the launch from French Guiana, collaborators in the mission, the ESA, the University of Geneva and the University of Bern held a press conference on the morning of the 5th December.

The gathered experts from the respective agencies discussed the mission–the ESA’s first ‘S-Class’ or small scale project–the international collaboration that brought it together and the role CHEOPS will play in the investigation of Exoplanets and the search for life elsewhere in the universe.

“After over six years of intensive work, I am, of course very pleased that the launch is finally in sight,” Willy Benz, CHEOPS’s principal investigator and professor of astrophysics at the University of Bern states.

The main role of CHEOPS will be to examine the ever-growing catalog of exoplanets, explains David Ehrenreich, CHEOPS Consortium Mission Scientist from the University of Geneva.

A replica of the CHEOPS telescope displayed at a press conference heled by the agencies responsible for the mission (Robert Lea)
A replica of the CHEOPS telescope displayed at a press conference heled by the agencies responsible for the mission (Robert Lea)

This involves selecting what Ehrenreich describes as ‘golden targets’ or exoplanets that missions such as the James Webb Space Telescope (JWST)–set to launch in 2021 from the same site—can follow-up on in order to perform in-depth examinations. As the JWST will search for signs of habitability–mainly indications of water and methane– it is a massive advantage for it to have preselected targets to study.

CHEOPS will enforce this selection process by examining nearby bright stars that are known to host exoplanets–particularly those with planets in a size range of Earth to Neptune. By measuring the transit depths as these planets cross their host star–the sizes of the planets can be accurately ascertained and then the researchers can also calculate their density and in turn, their composition–if they are rocky or gaseous, for example. The mission should also be able to determine if the planets possess deep oceans–believed to be a key component for the development of life.

A Small Mission Can Answer Big Questions

Kate Issak, a CHEOPS project scientist from the ESA explains how the mission–the first part of the Cosmic Vision 2015-2025 program–differs from previous endeavors undertaken by the agency: “CHEOPS is the first S-class mission for ESA, meaning it has a small budget and a short timeline to completion.

“Because of this, it is necessary for CHEOPS to build on existing technology.”

The cost of CHEOPS is an estimated 50-million Euros and it has taken 5 years to complete after being greenlit in 2014. Whilst this may not seem like a small amount of money or a short period of time, the cost and preparation time of the JWST–about 9 billion Euros and 7 years–very much puts both into perspective.

But neither a short timeline to completion or a small budget nor the fact that it mainly bridges the gap between past and future investigations will stop CHEOPS from attempting to answer some of the biggest lingering questions in exoplanet research.

Ehrenreich lays out some of the big questions that CHEOPS may have the potential to tackle, namely:

  • How do planets form?
  • At what rate do planets occur around other stars?
  • What are the compositions of these planets?
  • How do these compositions compare with the compositions of planets in the solar system?
  • Is our solar system unique or common?

And perhaps most interestingly for the general public and scientists alike:

  • Are any of these worlds habitable?

By tackling these questions CHEOPS and the ESA really get to the heart of both space exploration and exoplanet investigation.

CHEOPS: Empathising collaboration

As is fitting for a mission that probes such fundamental ideas as, how common is life in the universe, the ESA is throwing the use of the CHEOPS equipment out to other institutions and researchers.

Whilst 80% of CHEOPS’s operating time will be determined by the ESA’s mission program, Issak explains, the remaining 20% will be devoted to the wider scientific community. The projects and researchers that will be able to make use of this time will be determined based on merit alone.

“CHEOPS will build on the work of the consortium and benefit the scientific community as a whole,” promises Issak.

From Left to Right: David Ehrenreich, Willy Benz, Christian Leumann, Renato Krpoun and Kate Issak discuss the CHEOPS mission at the University of Bern (Robert Lea)
From Left to Right: David Ehrenreich, Willy Benz, Christian Leumann, Renato Krpoun and Kate Issak discuss the CHEOPS mission at the University of Bern (Robert Lea)

The idea of community spirit is built into CHEOPS’s DNA from its genesis, Willy Benz the mission’s principal investigator explains. The project brings together 11 individual nations each of which has made a specific contribution to the equipment aboard the satellite.

Issak adds “CHEOPS is an excellent example of how EU member states can work together.”

The ESA will follow-up on CHEOPS with PLATO (PLAnetary Transits and Oscillation of stars) project in 2026, and ARIEL (Atmospheric Remote-sensing Infrared Exoplanet Large-survey) mission in 2028.

Plato will specialise in the examination of rocky exoplanets orbiting in habitable zones around Sun-like stars, particularly focusing on the potential for these planets to hold liquid water. It will also examine seismic activity in stars–giving insight into the age and evolutionary stage of these planetary systems.

Ariel, meanwhile, will take exoplanet survey and characterisation to a whole new level of detail, enable to perform chemical censuses of a wide variety of planet’s atmospheres.

As the award of this year’s Nobel Prize in Physics to Michel Mayor and Didier Queloz for the discovery of the first exoplanet around a Sun-like star demonstrates, the search for exoplanets and the quest to categorise and understand them is currently one of the hottest research areas in science.

As such CHEOPS puts the ESA at the forefront of the race to discover how common our home planet and the solar system is, and potentially, answer an age-old question: are we alone in the Universe?

Asteroid Lutetia.

NASA and partners will be holding an asteroid impact exercise at conference next week

At next week’s 2019 Planetary Defense Conference, NASA, ESA, and the International Asteroid Warning Network will stage a “tabletop exercise” of an asteroid flying towards Earth.

Asteroid Lutetia.

Asteroid Lutetia seen by Rosetta spacecraft.
Image credits European Space Agency / Flickr.

Media outlets are always abuzz when an asteroid ‘near-misses’ our planet, and it’s easy to see why — there’s just something very exciting about a narrowly evading extinction. However, space agencies and governments around the world take the risk of impact with a near-Earth object (NEO) quite seriously. Given the potential for widespread panic such a scenario poses, any preparations are generally carried out discreetly, out of the public’s view.

The NEO threat

In the spirit of better communication, however, NASA’s Planetary Defense Coordination Office (PDCO), the European Space Agency’s Space Situational Awareness-NEO Segment and the International Asteroid Warning Network (IAWN) want to make the hazards posed by NEOs clearer for us laymen. Towards that end, they will organize — along with other U.S. agencies and space science institutions around the world — a “tabletop exercise” that will play out a fictional-but-realistic scenario for an asteroid on an impact trajectory with Earth at the conference, NASA announced.

NEOs are bodies such as asteroids or comets that come within 30 million miles (50 million kilometers) of Earth’s orbit. NASA and its international partners have been monitoring NEOs for over two decades now, keeping an eye out for any that might be gunning for Earth. However, preparations for such an impact have very rarely involved the public at large. The proposed exercise aims to address this shortcoming.

A tabletop exercise is basically a simulated emergency, used to accustom participants to the possible outcomes of such a disaster and help them see what needs to be done to mount a successful response. NASA plans to have attendees at the conference play out a NEO impact scenario developed by the NASA Jet Propulsion Laboratory’s Center for NEO Studies (CNEOS).

This type of exercise was specifically identified as part of the National Near-Earth Object Preparedness Strategy and Action Plan developed over a two-year period and published by the White House in June 2018. They’re not tightly scripted, aiming to let people ‘run wild’ and observe their response in conditions that mirror real life. This can then help us predict how NEO observers, space agency officials, emergency managers, decision-makers, and citizens might respond to an actual impact prediction.

Next week’s exercise events will occur over the five days of the conference. The scenario begins with the premise that on March 26th, a potentially-hazardous NEO dubbed 2019 PDC is discovered. After a ‘few months’ of tracking, observers predict that it has a 1% chance of impacting the earth in 2027. A 1% impact chance has been decided upon by the international space community as the threshold for action.

Exercise leaders will be briefing participants on the status of the scenario at the end of each day and soliciting response ideas and feedback, based on the latest fictional data. They will be asked to discuss potential preparations for reconnaissance and deflection missions, as well as plans to mitigate the effects of a potential impact.

“These exercises have really helped us in the planetary defense community to understand what our colleagues on the disaster management side need to know,” said Lindley Johnson, NASA’s Planetary Defense Officer. “This exercise will help us develop more effective communications with each other and with our governments.”

NASA has participated in six NEO impact exercises so far: three at Planetary Defense Conferences (2013, 2015, 2017) and three jointly with the Federal Emergency Management Agency (FEMA). The three NASA-FEMA exercises included representatives of several other federal agencies, including the Departments of Defense and State. Each exercise builds on lessons learned in the previous exercise. These exercises have shown that emergency management officials aren’t focused on the scientific details regarding the asteroid, but on more practical concerns.

“What emergency managers want to know is when, where and how an asteroid would impact, and the type and extent of damage that could occur,” said Leviticus Lewis of the Response Operations Division for FEMA.

However, NASA is a bit concerned with this approach. It’s those ‘scientific details’ that determine the outcome of an impact. So, while they’re working on developing new methods to determine asteroid characteristics, they also want to engage the public in these tabletop exercises to raise awareness of the hazards posed by NEOs.

“NASA and FEMA will continue to conduct periodic exercises with a continually widening community of U.S. government agencies and international partners,” said Johnson. “They are a great way for us to learn how to work together and meet each other’s needs and the objectives laid out in the White House National NEO Preparedness Action Plan.”

NASA wants to deflect a tiny asteroid’s orbit: humanity’s first planetary defense test

Credit: ESA.

With our busy lives and fairly stable day-to-day environment, it’s easy to forget that we’re actually sitting on a huge rock hurtling through space. Only a thin atmospheric and magnetic cushion is what separates us from total annihilation. This cushion is fairly good at keeping some cosmic intruders at bay, such as small asteroids, but larger objects could wreak havoc if they were to collide with Earth. Throughout our planet’s history, this has happened countless times, the dinosaur extinction being a prime example.

For some time, NASA has been working on an asteroid-deflection strategy and will soon launch a test mission to asteroid 65803 Didymos — a pair made of a smaller object called Didymoon that orbits around the larger 780-meter Didymos asteroid. The Double Asteroid Redirect Test (DART) project involves slamming a small probe into Didymoon, which measures only 160 meters in diameter, about the size of the Great Pyramid in Giza. The impact would slightly veer Didymoon away from its normal orbit around Didymos, informing NASA what kind of punch would be needed to deflect a real threat to Earth.

[panel style=”panel-warning” title=”Danger from above” footer=””]An impact with an asteroid isn’t the likeliest thing to happen in the universe. However, despite its low probability, such a scenario is a high-consequence event which requires “some degree of preparedness,” according to the authors of the new 18-page document titled the “National near-Earth Object Preparedness Strategy and Action Plan”.

NASA has so far cataloged about 18,310 objects of all sizes, of which just over 800 are 140 meters or larger. A 2005 congressional mandate tasked the agency with tracking 90 percent of the near-Earth objects larger than 140 meters. NASA is just one-third of the way there, however.

While big asteroids, such as the kind that wiped out the dinosaurs 65 million years ago, are absolutely brutal, that doesn’t mean that we shouldn’t be worried by anything smaller. For instance, a 40- to 60-meter asteroid that exploded over Tunguska, Russia, leveled 2,000 square kilometers of forest. If the same were to happen over New York City, it would cause millions of casualties. [/panel]

Didymoon will be by far the smallest asteroid ever explored by us — but even at its seemingly puny size, it would be enough to cause a continental-scale catastrophy if it slammed into Earth. The plan is to launch DART in 2021, with the goal of ramming into Didymoon in 2022 in order to change the course of the tiny world. In 2022 the double asteroid system will be only 11 million km (about 7 million miles) from Earth, which is why NASA is in quite a hurry.

Illustration of Hera at smallest asteroid ever visited. Credit: ESA.

Illustration of Hera at smallest asteroid ever visited. Credit: ESA.

If all goes well, the European Space Agency (ESA) will launch a follow-up mission called HERA in order to examine the impact.

“Such a binary asteroid system is the perfect testbed for a planetary defense experiment but is also an entirely new environment for asteroid investigations. Although binaries make up 15 percent of all known asteroids, they have never been explored before, and we anticipate many surprises,” Ian Carnelli, Hera project manager, told Earth Sky.

Using a small fleet of CubeSats, the HERA mission will measure the masses of the two asteroids, their surface properties, their new orbits, and the impact site itself. ESA hopes to launch the mission by 2026.

“This will give us a good estimate of the impact’s momentum transfer, and hence its efficiency as a deflection technique,” explains ESA’s Hera project scientist, Michael Küppers. “These are fundamental parameters to enable the validation of numerical impact models necessary to design future deflection missions. We will better understand whether this technique can be used even for larger asteroids, giving us certainty we could protect our home planet if needed.”

Moon.

The European Space Agency wants to mine the moon for oxygen and water

I think we have some of those down here already!

Moon.

Image credits Robert Karkowski.

The ESA just signed a one-year contract with Europe’s largest launch services provider, ArianeGroup, to study the feasibility of mining on the moon. Should everything go according to plan, ESA wants to launch the mission by 2025, the Popular Mechanics reports.

Moondust

The mission would focus on the lunar regolith, the dust-like soil covering our moon. It’s not exactly what we’d call ‘soil’ back here — on Earth, soils contain quite a lot of organic matter. Regolith, however, does contain molecular oxygen and water. It’s also quite rich in helium-3 isotopes, which “could provide safer nuclear energy in a fusion reactor, since it is not radioactive and would not produce dangerous waste products,” according to the ESA.

[This study is] “an opportunity to recall the ability of Ariane 64 to carry out Moon missions for its institutional customers, with a payload capacity of up to 8.5 metric tons,” says André-Hubert Roussel, CEO of ArianeGroup.

“In this year, marking the fiftieth anniversary of Man’s first steps on the Moon, ArianeGroup will thus support all current and future European projects, in line with its mission to guarantee independent, sovereign access to space for Europe.”

The mission would launch on an Ariane 64 rocket. The vehicle is still in the works and is a variation of the company’s Ariane 6 rocket with an extra four strap-on boosters. Berlin-based PTScientists, a former Google Lunar XPrize competitor, will also be involved in the study. ArianeGroup will handle the rocket and PTScientists will design and build the lander to actually touch-down on the moon.

“We are very pleased with the confidence placed in us by the European Space Agency,” said Robert Boehme, CEO and founder of PTScientists, in a press statement.

While the mission is being evaluated and the hardware is being set-up, ESA spacewalk instructor Hervé Stevenin and ESA astronaut Matthias Maurer are working together with geologists and engineers to simulate a lunar spacewalk in the desolate volcanic area of Lanzarote, Spain as part of Pangaea-X. This is a test campaign that set up by ESA to pool together expertise on space exploration, high-tech survey equipment, and geology meant to train the crewmembers of this future mission.

Spacesuits are bulky, uncomfortable things. They also limit an astronaut’s range of motions by quite a large margin. You can’t kneel down or bend over in a pressurized suit in space, the gloves make it hard to handle anything, arm movement is restricted by the suit’s articulated joints, and the helmet limits the field of view. The astronauts training with Hervé are testing operation concepts and equipment prototypes designed to take into account this limited range of movement they’ll experience in a suit. Their current training will make them feel at ease once they set foot on the moon.

“We do not have a lunar spacesuit for these tests, but after spending many hours training with NASA’s spacesuits we are accustomed to the limitations of mobility. We applied this knowledge – and our body memory – to testing the lunar tools,” says Hervé.

The spacewalkers’ gear was outfitted with video cameras that transmitted live feeds to the scientists. Wide angle videos, 360 panoramas, close-ups, and microscopic images were sent to the ‘spacewalk coordinator’ and other scientists monitoring the simulated mission from mission control.

“The next generation of lunar explorers will be trained in relevant scientific disciplines, but there will always be more expertise on Earth,” says Samuel Payler, research fellow at the European Astronaut Centre in Cologne, Germany.

“The challenge is to have this expertise transmitted to the astronauts during a moonwalk to make the best decisions based on science. Sharing data in real time, including images and video, is an essential part of this.”

Sun.

NASA eavesdropped on the Sun, and they made a video so you can hear it too

With a bit of help from NASA, you can now hear the sun’s roar — and it’s glorious.

Sun.

The Sun’s surface seen in ultraviolet light, colored by NASA.
Image credits NASA Goddard.

Although you never hear it, the Sun is actually pretty loud. This massive body of superheated, fusing plasma, is rife with ripples and waves generated by the same processes that generate its light and heat — and where there’s motion, there’s sound. We never get to hear it, however, as the huge expanse of nothing between the Earth and the Sun acts as a perfect acoustic insulator.

With some of ESA’s (the European Space Agency) data and a sprinkling of NASA’s magic, however, you can now hear the Sun churn in all of its (surprisingly tranquil) glory.

Hear me roar (softly)

“Waves are traveling and bouncing around inside the Sun, and if your eyes were sensitive enough they could actually see this,” says Alex Young, associate director for science in the Heliophysics Science Division at NASA’s Goddard Space Flight Center.

What Young is referring to are seismic waves, a type of acoustic waves — the same kind of motion that causes earthquakes in rocky planets — that form and propagate inside the Sun. Hypothetically, if you were to look at the star with the naked eye, you could actually see these waves rippling through its body and surface. Stars are formed of a much more fluid material than most planets, and so their bulk flows more readily under the sway of seismic waves — wiggling just like a poked block of Jell-O.

As most of us learned in early childhood, however, one cannot look directly into the Sun for long. Luckily for us, ESA recently embarked on a one-of-a-kind mission: they sent the Parker Solar Probe hurtling towards our star. Using its SOHO Michelson Dopler Imager (MDI) instrument, the probe recorded these motions inside the Sun. Researchers at NASA and the Stanford Experimental Physics Lab later processed into a soundtrack.

It’s not half-bad, as far as tunes go. I actually find it quite relaxing. Check it out:

[panel style=”panel-info” title=”Hear me roar” footer=””]

The sounds you hear in NASA’s clip are generated by the motions of plasma inside the Sun. These are the same processes that generate local magnetic fields inside the star and push matter towards the surface, causing sunspots, solar flares, or coronal mass ejections — the birthplace of space weather.

Space weather phenomena are associated with intense bursts of radiation, to which complex technological systems are susceptible. So most of our infrastructure, from satellites — and with them, cell phone networks, GPS, and other types of communication — transportation, and power grids.[/panel]

It took a great deal of work to turn the readings from Parker into something usable. Alexander Kosovichev, a physicist at the Stanford University lab, processed the raw SOHO MDI data by averaging Doppler velocity data over the solar disc and then only keeping low degree modes. These low degree modes are the only type of seismic waves whose behavior inside stars is known and accessible to helioseismologists. Afterward, he cut out any interference, such as sounds generating by whizzing of instruments inside the craft. He then filtered the data to end up with uninterrupted sound waves.

While scientists probably enjoy a groovy track just as much as the rest of us, the soundtrack actually has practical applications. By analyzing the sounds, researchers can get a very accurate picture of the churnings inside of our Sun — much more accurate than previous observations could provide.

“We don’t have straightforward ways to look inside the Sun,” Young explains. “We don’t have a microscope to zoom inside the Sun. So using a star or the Sun’s vibrations allows us to see inside of it.”

A more comprehensive understanding of the motions inside the Sun could allow researchers to better predict space weather events.

Story via NASA.

Air pollution movement. Credit: ESA.

Most advanced air quality satellite releases first open data to the public

Air pollution movement. Credit: ESA.

Copernicus Sentinel-5P carbon monoxide measurements in November 2017 show long-range transboundary air pollution transport from India to China. Credit: ESA.

In order to study our planet’s climate and atmosphere in greater detail than ever before, the European Space Agency (ESA) flies a fleet of satellites called Sentinels that constantly monitor Earth. Now, ESA has announced that data collected by one of its most recently launched satellites are available for the public, which will help improve air quality forecasts but also impact environmental policy.

Mapping worldwide air pollution for a cleaner future

The Sentinels are designed to address six main themes with their observations: atmosphere, climate change, marine environment, emergency management and land and security. These observations are beamed back to Earth, where they are analyzed and processed into usable data by the Copernicus Atmosphere Monitoring Service (CAMS).

In October 2017, ESA launched Sentinel-5P –– the most recent satellite in Copernicus’ fleet and the precursor to Sentinel-5. It’s the first Copernicus mission solely dedicated to monitoring the atmosphere, being meant to fill the data gap between the retirement of the Envisat satellite and NASA’s Aura mission.

Specifically, the Sentinel-5P mission is preoccupied with air quality. When this information is combined with ground — and other satellite-based observations, scientists become better equipped to assess the state of the atmosphere — not only today but also in the future.

Sentinel-5P tropospheric nitrogen dioxide measurements over Europe, Africa, Middle East, and India from April 2018 (averaged). Sentinel-5P’s Tropomi instrument can detect air pollution over individual cities, but also where these are sourced from, effectively identifying pollution hotspots. Credit: ESA.

“We often hear about climate change and the depletion of the ozone layer when we consider why we need to monitor the atmosphere,” says Sentinel-5P mission manager, Claus Zehner. “But air quality is also a huge global problem. It affects the health of humans and influences agriculture and the economy in general.”

The best part is that all of this information is open and free to use by the public — by everyone. It can be used, for instance, to devise more accurate air quality forecasts, similarly to how most people check weather forecasts today.

Previously, Sentinel-5P readings were verified in a preliminary phase where early data was compared with the CAMS forecasting system. This procedure allowed the detection and solving of “teething” issues, so the instruments could be calibrated.

“Anybody can access the Sentinel-5P data, but it is complex and has to be processed before it is useful for addressing specific questions,” explains Richard Engelen, Deputy Head of CAMS. “CAMS does this processing so that the data user doesn’t have to, by combining Sentinel-5P data with observations from other satellite instruments to provide combined datasets as well as forecasts for the next few days.”

Central to Sentinel-5P’s ability to map trace gases in the atmosphere, such as nitrogen dioxide, ozone, and aerosols, is a spectrometer called TROPOMI (Tropospheric Monitoring Instrument) — the most advanced multispectral imaging spectrometer to date. Thanks to its high spatial resolution of up to 7 x 3.5 km, it can even detect air pollution over individual cities.

“In combination with the improved sensitivity of the detectors we now have a spectrometer that is about 10 times better than its predecessor,” said Harry Förster from the Netherlands Space Office in a statement. 

The first ozone retrievals of Copernicus Sentinel-5P show the closing of the ozone hole over the South Pole during November 2017. Credit: ESA.

The first ozone retrievals of Copernicus Sentinel-5P show the closing of the ozone hole over the South Pole during November 2017. Credit: ESA.

This kind of real-time monitoring of emissions and key pollutants will help inform environmental agencies and guide policy-makers, directly benefiting citizens — particularly those suffering from some form of respiratory disease. For instance, having a more accurate air quality forecast over the coming week might help individuals take precautions.

“We have been using preliminary Sentinel-5P data in the CAMS global system. Early impressions are excellent and we expect that Sentinel-5P will soon become one of the most important data sources underpinning the quality of CAMS information products,” Engelen said in a statement to the press.

Air pollution is the single largest environmental health risk humans face, according to the World Health Organization. In China, air pollution is responsible for cutting a person’s lifespan by three years, while in India, air pollution claims four years of a person’s life on average. Missions such as Sentinel-5P can help us make informed decisions such that we might all breathe cleaner air.

Sentinel-5P data — but also Sentinel-1,-2, and -3 — are available on the Copernicus website. In the future, the geostationary Sentinel-4 and polar-orbiting Sentinel-5 will monitor the composition of the atmosphere.

NASA and ESA team up to bring Martian soil back home

It’s like the Avengers and Justice League teaming up — except it’s real, and it’s all in the name of science.

Ambitious plans

A look back at a dune that NASA’s Curiosity Mars rover drove over. Image credits: NASA / JPL.

NASA and the European Space Agency (ESA) have signed a statement of intent today to explore ways to bring martian soil samples back to Earth. The venture, which was announced at a meeting in Berlin, Germany, will allow us to better understand Mars’ geological history, but it won’t be easy.

Having orbiters around Mars and sending rovers to the surface of the planet taught us a great deal about what Mars is like, and what it was probably like in its geological past. However, there’s only so much information we can draw from remote probes. The next step would be to take the samples back to Earth where they could be analyzed by sophisticated labs, and where any results could be independently verified by several research centers.

If life existed (or still exists) on the Red Planet, it’s would probably be exclusively microbial in nature, and almost certainly underground, where it’s shielded from the devastating radiation. Analyzing soil samples could shed new light on that mystery, but it won’t be easy.

The project entails at least three missions: two launches from Earth and an unprecedented launch from Mars.

Interplanetary geocaching

The first mission, NASA’s 2020 Mars Rover, will collect up to 31 surface samples in pen-sized canisters as it explores the Red Planet. In the same time period, ESA’s ExoMars rover, which is also set to land on Mars in 2021, will be drilling up to two meters below the surface, looking for evidence of life. The canisters will be filled and readied for a later pickup which is something the ESA calls “interplanetary geocaching.” The second mission would have a small fetch rover land nearby and pick up the samples, placing them in the so-called Mars Ascent Vehicle — a small rocket which can launch them into orbit. The third mission would have a Mars orbiter rendezvous with the samples, pick them up, and return to Earth, where the samples would be collected and quarantined for analysis.

ExoMars rover 360. Findings from the ExoMars rover mission will help decide which samples will be brought back to Earth. Credit: ESA/ATG medialab.

David Parker, ESA’s Director of Human and Robotic Exploration, said that the ambitious mission could greatly benefit from a strong partnership between the European and American space agencies. He also outlined the importance of the mission.

“A Mars sample return mission is a tantalising but achievable vision that lies at the intersection of many good reasons to explore space.

“There is no question that for a planetary scientist, the chance to bring pristine, carefully chosen samples of the Red Planet back to Earth for examination using the best facilities is a mouth-watering prospect. Reconstructing the history of Mars and answering questions of its past are only two areas of discovery that will be dramatically advanced by such a mission.

“The challenges of going to Mars and back demand that they are addressed by an international and commercial partnership – the best of the best. At ESA, with our 22 member states and further cooperating partners, international cooperation is part of our DNA.”

In addition to finding out whether Mars hosts life or not, astronomers also want to establish a chronological baseline for the Red Planet, which is currently based on limited data and extrapolations from the Moon. Furthermore, this might help us understand the constraints that life requires in order to emerge and flourish. Lastly, the soil samples will help us answer an important question about a manned mission to Mars: how dangerous is the Martian soil? There are reasons to believe that it could be a major breathing hazard as well as a source of potential damage and erosion.

ESA’s ExoMars orbiter is already circling Mars, investigating its atmosphere, and NASA still has two active rovers on the planet’s surface, Curiosity and Opportunity.

Watch: real footage of cosmic particle ‘snow’ on comet 67P

It looks like a winter wonderland scene from an old black and white film but — don’t be fooled — what you’re seeing is real footage from the surface of the comet 67p/Churyumov-Gerasimenko. These images were captured by the European Space Agency’s Rosetta probe over the course of 25 minutes on the 1st of June, 2016, and processed by an awesome human who posted the whole thing on twitter.

The raw images were made with Rosetta’s OSIRIS, or Optical, Spectroscopic, and Infrared Remote Imaging System. What we’re seeing in the foreground is the comet’s surface, as seen by the probe from a distance of several kilometers. In the background, you can see stars belonging to the constellation Canis Major.

What looks like snow here are actually cosmic rays (charged subatomic particles), which register as streaks of light as they hit the camera’s sensor. It’s true, however, that there is some actual snow in the footage — specks of dust and ice.

The Rosetta spacecraft and its lander, Philae, reached 67P in 2014 after a 10-year round-trip journey of four billion miles.  The probe crashed into the comet’s surface in 2016.

Earth’s oceans generate a second, tiny, previously-unknown magnetic field, ESA satellites find

As it transits through the skies above, the Moon’s pull on the ocean’s salty depths generates a second, if much weaker, global magnetic field.

The ebb and flow of salty water, caused by our Moon’s gravitational pull, can induce their own magnetic field — one which a trio of European Space Agency’s (ESA) satellites has mapped in exquisite detail.

Known as “Swarm”, the trio of satellites was blasted off into orbit back in 2013 to help us better understand the planet’s magnetic field. Most of that field is produced by the churnings of molten iron in the Earth’s core, functioning like a massive underground dynamo. There are other secondary effects, however, such as those produced by human activity — and those are the effects Swarm was intended to peer into.

Imagine the surprise among ESA’s researchers when the satellites stumbled into a whole new magnetic phenomenon.

“It’s a really tiny magnetic field. It’s about 2-2.5 nanotesla at satellite altitude, which is about 20,000 times weaker than the Earth’s global magnetic field,” Nils Olsen, from the Technical University of Denmark, told BBC News.

What set the satellite trio apart from its peers — and enabled this discovery — is the way they ‘see’ water. Other devices we’ve sent in orbit record tides as a change in sea-surface height, but Swarm’s magnetic instruments view the movements of the entire column of water, all the way down to the seabed.

Water is diamagnetic, meaning that it has weak magnetic qualities when a magnetic field is applied to it. However, adding salt reduces its diamagnetism but makes it a good, but not great, electrical conductor — meaning it will start interacting with magnetic fields, relatively weakly. Still, oceans house humongous quantities of water, and as tides cycle around ocean basins, the overall effect is enough to ‘pull’ the geomagnetic field lines along. The interaction between saltwater and the Earth’s magnetic field also generates electrical currents, which, in turn, induce their own magnetic signals.

Studying the ebb and flow of this second magnetic field can let us peer into the movement of deep bodies of water. Oceans capture, store, and move a lot of heat around, and Swarm’s findings could help researchers build better models of Earth’s systems — particularly useful in understanding the effects of climate change.

The magnetic signature of the tides causes a “weak magnetic response” deep below the sea, Olson explained — which could allow us to peer into the electrical goings-on of our planet’s lithosphere and upper mantle. Such data will help us better map these structures, as well as the tectonic activity that drives earthquakes and volcanic eruptions.

“Since oceans absorb heat from the air, tracking how this heat is being distributed and stored, particularly at depth, is important for understanding our changing climate,” Olson said in a statement, adding that the discovery “gives us a truly global picture of how the ocean flows at all depths.”

The professor was speaking at the European Geosciences Union General Assembly (EGU) in Vienna, Austria, where a clutch of new Swarm results have been released.

Wildfires roar through Southern Cali as NASA and ESA satellites watch, powerless to intervene

The scope and destructiveness of Southern California’s wildfires were captured in chilling detail by ESA satellites earlier this week.

Ventura wildfires.

Image via DailyDot.

Wildfires have turned large swaths of California into a Mordoresque landscape over the last few months, but flames won’t seem to spare the golden state. Dramatic pictures of the most recent blaze to erupt in Southern California were captured by the European Space Agency’s Sentinel-2 spacecraft on Tuesday, Dec. 5, revealing areas of active fires and a massive burn scar a stone throw’s away from the city of Ventura.

Wildfires Ventura ESA.

Massive burn scar just east of the California city of Ventura, along with areas of active fires.
Image credits ESA.

Sentinel-2’s photo captures billowing smoke rising from the areas of active fires. The same can be seen in another image captured Tuesday by the Moderate Resolution Imaging Spectroradiometer (MODIS) instrument aboard the Terra satellite operated by NASA. MODIS took a wider view than the instruments on Sentinel-2, showcasing the tsunami of smoke flowing west, from Ventura and north Los Angeles’s hills into the Pacific Ocean.

Wildfires Cali NASA.

Image captured by the MODIS instrument aboard NASA’s Terra satellite shows smoke plumes rising from the Southern California wildfires.
Image credits NASA.

The Ventura fires first caught Monday and spread with a fury due to Southern California’s Santa Ana winds. As of data available on Wednesday afternoon, the flames have burned through 83,000 acres (33,600 hectares), CNN reports. Just this October, Northern California was ravaged by wildfires which cindered 245,000 acres (99,150 hectares), more than 8,900 houses and other buildings, and claimed over 40 lives.

 

 

Credit: Lucasfilm

More than a million years from now, our solar system will briefly house two stars

A double sunset such as the fictitious one on Tatooine from Star Wars has always been on many people’s minds. About 1.3 million years from now, if anyone is still around, he could actually experience a similar scenery here on Earth.

Credit: Lucasfilm

Credit: Lucasfilm

Uninvited stellar guests

Nothing is static in the Universe. Though our senses tell us we’re standing still, since the days of Copernicus we’ve known that the planet we call home revolves around the Sun, which in turn moves around the center of Milky Way, which yet again revolves around the center of mass lying in between Andromeda and Milky Way. In other words, everything is in perpetual motion relative to a reference point. This means that sometimes cosmic objects and systems can behave in very surprising ways.

A massive survey of 300,000 stars and their motion relative to the Sun was performed by astronomers working with the ESA’s Gaia satellite. The scientists plotted the stars’ closest approach to the Sun determined for up to five million years in the past and future. They found 97 stars which should pass within 150 trillion kilometers, with 16 coming within about 60 trillion km.

A particular encounter stands out, that with Gliese 710, which will pass within just 2.3 trillion km or about 16 000 Earth–Sun distances, some about 1.3 million years from now. For a sense of measure, the outermost planet of the solar system, Neptune, orbits around the sun at 30 Sun–Earth distances.

That puts Gliese 710 well within the Oort Cloud, a humongous shell of icy objects that exist in the outermost reaches of the solar system, extending out to 15 trillion kilometers from the Sun or 100 000 times the Sun–Earth distance.

Understanding alien stars that approach our solar system is important work that might one day even avert a planetary catastrophe. It’s thought that most comets in our solar system come from the Oort Clouds. These are mainly perturbed by the gravitational influence of stars which jolts them into orbits that bring the comets closer to the inner solar system. Some of these comets could enter a collision course with Earth or other planets.

Coming this close to the sun, Gliese 710 will certainly stir the Oort Cloud bee-hive, though in what way remains unclear at this point.

We do know that this alien star has a mass of 60% that of our Sun and that it travels much slower than most stars: nearly 50 000 km/h at closest approach, compared with the average 100 000 km/h. This relatively slow motion will likely amplify the Oort Cloud perturbation effect than otherwise in the case of faster stars.

What’s also certain is that Gliese 710 will shine brightly in the night’s sky as seen from Earth’s surface. Astronomers estimate its brightness will be three times that of Mars.

Meeting a rogue

The following animation put together by ESA focuses on Gliese 710 wandering through the galaxy, ultimately performing a close encounter with our Sun in 1.3 million years by passing within the Oort Cloud reservoir of comets in the outskirts of our Solar System. The ESA’s press release explains further that:

“The motion can be likened to what an observer standing beside a road would see looking at an approaching car, and then swinging around to continue to follow it as it moves away. As a result, the objects in the background – in this case distant stars – become blurred as you move quickly to maintain a visual on the passing object.”

Of course, Gliese 710 wouldn’t be the first star to cause a racket in our solar system’s backyard. About 70,000 years ago, during a time when our ancestors were busy staying alive in the aftermath of the Toba super-eruption, a low-mass star system nicknamed “Scholz’s star” passed roughly 52,000 astronomical units away from the sun.

Scientific reference: “The completeness-corrected rate of stellar encounters with the Sun from the first Gaia data release,” by C.A.L. Bailer-Jones, is published in Astronomy & Astrophysics.

A lunar base concept drawing. Credit: Wikimedia Commons.

China and Europe have talks to build a ‘Moon Village’ together

A high-ranked Chinese official from the country’s space agency recently revealed that China and the European Space Agency (ESA) could partner to build a moonbase together. For some years, China has been dabbling with the idea of building a moon base on its own. A joint venture with an arguably more experienced partner like the ESA, however, will improve the odds of success.

A lunar base concept drawing. Credit: Wikimedia Commons.

A lunar base concept drawing. Credit: Wikimedia Commons.

Two heads are better than one

The space race of the ’60 and ’70s was more about a show of force between two sole superpowers, the USA and the Soviet Union. After the latter collapsed, space flight and exploration suffered as the USA saw little incentive to go farther than any ‘commie’ has gone before. The last human boots touched down on the moon in 1972 and since then NASA’s budget gets pressured with cuts every year. That’s what happens, basically, when space exploration becomes a show of military might and brawn, not an honest scientific endeavor.

But then the International Space Station happened — a massive international collaboration spanning 15 different countries. The $100-billion space station is the most complex international scientific and engineering project in history, but also the largest structure humans have ever erected in space. Inside, there’s more livable room than a conventional five-bedroom house. It also has two bathrooms, gym facilities, and a 360-degree bay window.

No country could have single-handedly engineer and finance such a huge project. Built brick by brick, so to speak, the ISS has been constantly upgraded since its first module was launched from Russia in 1998. It’s a testament to how countries can band together for the common good of science and humanity.

Well, some countries at least. China was never allowed to contribute a nut or bolt to the International Space Station because the United States always objects out of concern that China would use the tech access to advance its military program. But a lot has happened in the last 20 years.

“The Chinese have a very ambitious moon programme already in place,” said Pal Hvistendahl, a spokesperson for the European Space Agency, in a statement. “Space has changed since the space race of the Sixties. We recognise that to explore space for peaceful purposes, we do international cooperation.”

China’s first manned flight only took place in 2003, or more than 42 years after cosmonaut Yuri Gagarin return from Earth’s lower orbit. It’s catching up fast, though. Its first space station, the eight-ton Tiangong 1 (Heavenly Palace) launched on 29 September 2011 and hosted two three-person crews between 2012 and 2013. The nation’s second space lab, Tiangong 2, launched last year — the final preparation before China launches a full-fledged space station in 2020. Also last year, China launched a “hack-proof” quantum communication satellite on a 53m-tall rocket designed, like anything they do, by Chinese engineers. Despite it having a budget five times smaller than NASA’s, the Chinese space program made 14 successful launches in 2013 compared to NASA’s 19 and Russia’s 31.

China’s space program also set its sights after new milestones. In 2013, it landed a small rover on the lunar surface which continued to relay back for years. This gave Chinese engineers enough confidence to plan a similar mission on the far side of the Moon for 2018, which would be world’s first. In 2020, China also wants to send a rover to Mars, joining the race with ESA and NASA.

“You will see the Chinese quite visibly begin to match the capacity of the other spacefaring powers by 2020,” predicts Brian Harvey, space analyst and author of China in Space: The Great Leap Forward.

“Science is becoming more and more important in the Chinese space programme,” Wang Chi of the National Space Science Centre, Chinese Academy of Sciences, told The Guardian last year. “We are not [just] satisfied with the achievements we have made in the fields of the space technology and space application. With the development of the Chinese space programme, we are trying to make contributions to human knowledge about the universe.”

China’s biggest ambition, however, is to send a Chinese astronaut to the moon and, ultimately, build a lunar base. It tentatively wants to achieve this by 2030 but now with the help of the ESA, it could happen far sooner.

Hopefully, the two can move beyond just ‘talks’. After all, China and the ESA are already working together. After China returns samples from the far side of the moon, some will arrive at ESA labs for study.

exomars lander

Orbiting probe take snapshot of Mars Landers’ grave — RIP, Schiaparelli

exomars lander

Credit: NASA/JPL-Caltech/MSSS

Just one minute before it commenced its descent to the red planet’s surface last week, all communications with ESA’s mars lander dropped and a link couldn’t be established afterward. It was a sad day for the hundreds of scientists, engineers, and staff from the European Space Agency who all expected the worse. Sadly, Schiaparelli seems to have indeed succumbed to a violent death as footage from the crime scene taken by an orbiting NASA spacecraft suggests.

NASA’s Mars Reconnaissance Orbiter (MRO) captured several photographs that show a bright feature that uncannily resembles a parachute and a dark patch that seems to be the lander’s crash site.

“Estimates are that Schiaparelli dropped from a height of between 2 and 4 kilometers [1.2 to 2.5 miles], therefore impacting at a considerable speed, greater than 300 km/h [186 mph],” the ESA wrote on its website. 

“The relatively large size of the feature would then arise from disturbed surface material,” they added. “It is also possible that the lander exploded on impact, as its thruster propellant tanks were likely still full. These preliminary interpretations will be refined following further analysis.”

The dark patch is only 3.4 miles west of Schiaparelli’s intended landing site, at Mars’ Meridiani Planum, and well within the 62 miles long by 9 miles wide crash ellipse calculated by scientists.

MRO used its low-resolution CTX camera to take these snapshots, but this week when it will make its next flyby the orbiter will use its High Resolution Imaging Science Experiment (HiRISE) camera which should give us a much better look.

Schiaparelli and the Trace Gas Orbiter (TGO). an orbiting spacecraft run by Russia’s Roscosmos space agency, travel in tandem to the red planet and separated shortly before the lander was supposed to make its soft landing. The TGO also had its watershed moments when it had to make a delicate 139-minute-long maneuver to lock itself into Mars’ orbit. All went well, and the TGO is now circling the planet every 4.2 days on a highly elliptical path. Its mission will be to study methane signatures, a low-abundance gas which is of particular interest for astrophysicists since it’s considered a proxy for life.

As for Schiaparelli, the lander was supposed to test technology that is destined to help a life-hunting rover safely touch down on Mars in 2021. At least ESA now knows how not to do it.

ESA transmits ExoMars’ landing commands, eagerly awaits the event

The Schiaparelli spacecraft has just received its landing commands from the European Space Agency (ESA), and is expected to touch down on Mars on Oct. 19.

Image credits ESA.

The ESA’s ExoMars mission is nearing its most climactic point — the touchdown. On March 14, the agency launched two connected crafts, the Trace Gas Orbiter and its Schiaparelli lander on a quest to reach the Red Planet. The two have almost completed their long trek through space, and will separate on Sunday, Oct. 16 above Mars. If everything goes well, Schiaparelli will land on the planet’s surface three days later, while the Trace Gas Orbiter will remain in orbit around it to study its atmosphere.

ESA put together a video to detail the crafts’ commands and landing procedure — basically, Schiaparelli will have to discharge the front and back aeroshells, deploy its descent sensors, braking parachutem and landing thrusters for a controlled impact on the surface. Here’s the video:

 

The craft will land in the Meridiani Planum, a flat region close to Mars’ equator. The lander will hit the atmosphere at about 21,000 km/h (13,000 mph), and will need to decelerate to safe landing speeds in about 6 minutes, ESA officials said in their statement. The craft’s sensors will monitor its height above the surface starting at 7 km (4 miles) altitude. When it reaches about 2 meters (6.5 feet) from it, it will hover for a moment then cut its thrusters for touchdown.

It will then start beaming up information about Mars’ winds (direction and speeds), humidity, pressure, temperatures, and so on, to the Orbiter. ESA hopes the data will help us better prepare for ExoMars’ rover mission, scheduled for 2020.

 

Luna 27. Image: ESA

ESA and Russia join forces to put man back on the moon

The last time humans set foot on the moon was 1972. Feeling confident it had clearly showed its superiority over Russia, the US felt no more reason to prove itself and shut down subsequent missions. With the funding gone – and its budget has been thinning ever since – NASA had to settle for less ambitious goals, and it’s not like we can blame them. Building on outpost on the moon, versus say the International Space Station, is not only a lot more expensive, but also impractical. Recent findings, however, suggest that with today’s technology, there’s a lot to gain from having an outpost on the moon.

That’s because the interest has shifted from prestige to the potentially bountiful economic activities. Minerals, helium-3 (fuel) or precious metals can all be mined from the moon, trillions worth. But before you can shuttle minerals back from the moon, you at least need a footing of some sort. Understanding this, the European Space Agency and Roscosmos banded together to send a robotic probe to an unexplored region of the moon. The ultimate goal, they say, is to prepare the ground for humans.

Luna 27. Image: ESA

Luna 27. Image: ESA

According to the BBC, the Lunar 27 will land  on the edge of the South Pole Aitken (SPA) basin. Here it’s mostly dark, but precisely because the sun doesn’t shine that much this area is filled with iced water and other useful materials that haven’t been blasted like on other parts of the moon.

“The south pole of the Moon is unlike anywhere we have been before,” said Dr James Carpenter, Esa’s lead scientist on the project

“The environment is completely different, and due to the extreme cold there you could find large amounts of water-ice and other chemistry which is on the surface, and which we could access and use as rocket fuel or in life-support systems to support future human missions we think will go to these locations.”

One of ESA's designs for a lunar outpost. Image: ESA

One of ESA’s designs for a lunar outpost. Image: ESA

If the robot does well, proves it can drill and extract the resources required to sustain a permanent base on the moon, then the next logical step will be sending back astronauts to the moon. But even thought we’ve waited more than four decades for this to happen, it might take another one. Lunar 27 will begin its mission five years from now, and even if it proves successful it might take at least as much to prepare for a human stay. Landing humans on the moon just for the sake of it is of no necessity. It’s time for some serious action now. In fact, the moon is seeing the most interest from space agencies around the world since the Apollo landings, and if the Esa and Russia aren’t careful China might beat them to it. China will land a rover on the dark side of the moon in 2020, and plans to build an outpost by 2030.

 

Lakes on Titan might have formed like sinkholes on Earth

Researchers from the European Space Agency (ESA) and the National Aeronautics and Space Administration (NASA) have been trying to figure out how Titan’s seas formed – more exactly, how the depressions in which the seas are formed.

Artist impression of Saturn seen from Titan. Image: NASA JPL

Titan is Saturn’s largest moon and the only known satellite with an atmosphere and the only object other than Earth where clear evidence of stable bodies of surface liquid has been found. But don’t start thinking about water – Titan’s climate involves hydrocarbons such as methane and ethane. At its two poles, the moon features thousands of hydrocarbon lakes, many as big as the Great Lakes.

This happens because of Titan’s extremely low temperature, which keeps methane and ethane liquid. But having liquids is not enough for having lakes and seas – you also need some place where those liquids can accumulate: a depression.

They concluded that Titan’s depressions were formed through a similar process which forms sinkholes here on Earth: dissolution. Sinkholes are natural depressions typically caused by karst processes. Karst processes occur when the bedrocks are soluble, like in carbonate rocks (such as limestone or dolomite) or evaporitic rocks (such as gypsum or anhydrite). But unlike sinkholes on Earth, depressions on Titan take much longer to form.

Polar clouds, made of methane, on Titan (left) compared with polar clouds on Earth (right), which are made of water or water ice. Image via Wikipedia.

“We found that the dissolution process occurs on Titan some 30 times slower than on Earth due to the longer length of Titan’s year and the fact it only rains during Titan summer. Nonetheless, we believe that dissolution is a major case of landscape evolution on Titan and could be the beginning of its lakes.”

Still, this is just a theory for now, because of course, there is no way to observe the geological processes on Titan from ground level… yet. NASA’s Glenn COMPASS Team discussed at large the possibility of exploring Titan, Saturn’s largest moon, with a robotic submarine that would dive deep inside the oceans of liquefied natural gas

 

The two booster version of the Ariane 6 rocket. Science ministers from all the ESA member states will meet tomorrow to discuss its future. Image: ESA

ESA members meet to approve Ariane rocket in light of SpaceX competition

Tuesday morning, ministers from each of the 20 nations involves in the European Space Agency will meet to decide how they should fund their next missions. The plan is to come to terms with developing a much sought after upgraded version of the Ariane rocket, which services satellite launches – the bread and butter of the ESA. Across the ocean, rivaling SpaceX launches satellites nearly three times cheaper. An agreement is, thus, crucial if the ESA is to survive. Yet member states need to agree on other projects as well, like future endeavors to the International Space Station and a huge budget hole in  the agency’s flag ship mission – a rover destined for Mars and tasked with finding alien life.

A hard call that might make or break the European Space Agency

The two booster version of the Ariane 6 rocket. Science ministers from all the ESA member states will meet tomorrow to discuss its future. Image: ESA

The two booster version of the Ariane 6 rocket. Science ministers from all the ESA member states will meet tomorrow to discuss its future. Image: ESA

This isn’t your regular budget meeting. Tomorrow, ministers will have a very tough decision to make, since any way you look at the situation, there will be important compromises to be made. What’s certain is that the ESA needs to push forward the Ariane 6 rocket, an upgrade to the Ariane 5 which currently has a whooping 50% market share. But after SpaceX started launching satellites into space and even cargo to the International Space Station, the scales seem destined to shift. At the moment, a regular satellite launch with the ESA using the Ariane 5 costs $130 million. SpaceX does it for $50 million. Contracts will soon run out, and clients will likely move over seas to work with a much cheaper partner.

At the moment, the ESA’s main leverage is its history and tradition spanning more than 50 years, during which hundreds of launches were successfully made. SpaceX is an extremely young company, but under the guidance of its CEO, Elon Musk, it proved that it can make extremely huge leaps forward and they’re not only catching up, but innovating. In less than two years, SpaceX might ferry crews to the ISS – something the ESA has never been able to do. Then there’s other companies showing up – Boeing or Jeff Bezos’ Blue Origin.

Ariane 6 broken down into its main components. Image: ESA

Ariane 6 broken down into its main components. Image: ESA

Clearly, the ESA needs to step up its game if thousands of jobs are to be protected. The agency’s hope lies with the Ariane 6 (A6) – a much needed upgrade that will help the ESA lunch much bigger satellites at a much lower rate: only $60 to $70 million. Progress has been slow up until now, though, since Germany was holding out for a two-step project to upgrade the current Ariane 5 system. The country is now ready to go forward and invest an important chunk of the money needed. Mst of the money will be brought by France.

Germany wants something in return, however. If it’s to commit its support, Germany wants other member states, especially the important ones like UK, Italy and France, to continue to pledge their support for the International Space Station. In total, 3.8 billion euros ($4.7bn) are need, which will cover not only the A6’s development but also an upgrade to ESA’s small Italian-built Vega rocket.

Karim Michel Sabbagh, chief executive of satellite operator SES, said: “It would be very serious if there is no decision on Dec 2 because Europe would have a competitive delay that it would never manage to reverse.”

Although very similar to the A5, the Ariane 6 will have modular design, coming in two versions: one has two solid boosters that can launch 5 ton satellites to orbit, while the other has 4 solid boosters that can launch 11 ton satellites. This way, the ESA will have a nicely evened up market, being able to launch both medium-sized government missions, as well as big commercial telecom satellites; even two at a time with the 4 solid booster version.

The two Ariane 6 versions. Image: ESA

The two Ariane 6 versions. Image: ESA

The meeting in Luxembourg will likely see A6 finally come to light; matters with the ISS aren’t that certain. Even more in the dark is the poor old ExoMars rover, destined to reach Mars’ surface in 2018 and tasked with findings signs of present or long passed life. That is, if it ever lifts off the ground here on Earth. The mission is currently facing a huge $200 million budget hole which desperately needs filling up. Once A6 and the ISS are settled, we can only hope there will be some to spare for the ExoMars rover as well.

An uncertain future

EXOMARS is the first flagship mission of the Aurora program and is committed to developing an orbiter, landing module and rover that may conduct, unmanned and later manned, biological and geological studies on Mars. Image: ESA

EXOMARS is the first flagship mission of the Aurora program and is committed to developing an orbiter, landing module and rover that may conduct, unmanned and later manned, biological and geological studies on Mars. Image: ESA

Even if the A6 will soon be up and running, it looks like the ESA has been left behind. What will it do after SpaceX releases its reusable rocket system, which Musk promises will slash costs 100 fold? It’s not just SpaceX. As mentioned earlier, Boeing, Blue Origin and maybe other companies are joining in the game. Clearly, Europe’s cumbersome and sluggish bureaucracy is taking its toll. Maybe, it’s time for a reform; right, Europe?

It’s not over until the fat lady sings, though. The ESA has tons of experience and has proven time and time again that it can handle incredibly complex projects, like the spectacular landing of the Rosetta probe on the surface of a comet.