Tag Archives: dust

“Godzilla” dust cloud races from the Sahara to the US

Every year during summer, the wind carries large plumes of desert dust particles from the Sahara Desert in Africa across the Atlantic Ocean.

Now, thanks to satellite data from the European Space Agency (ESA), we can see in incredible detail the extent of this year’s dust plume — it was an unusually large, “Godzilla” plume.

Credit ESA

The Saharan dust storm, also known as the Saharan Air Layer, typically forms between late spring and early autumn, peaking in late June to mid-August. Dust particles from the African desert are swept up into the dry air by strong winds and thunderstorms. The dust can then float for days or even weeks on end.

This phenomenon happens every year but the plume now registered is described as unusual due to its size and the distance travelled. Researchers at the National Oceanic and Atmospheric Administration (NOAA) estimated that the dust plume is between 60 to 70% dustier than average, making it the most massive since records began 20 years ago.

The ESA created an animation that shows the spread of particles from the Saharan dust plume moving westward from June 1 to June 26 this year. The data, captured by the ESA’s Copernicus Sentinel and Aeolus satellites, shows the dust plume on its great journey, around 1.8 to 3.7 miles above the ground.

Normally, Saharan dust plumes disperse in the atmosphere and sink into the Atlantic before reaching the Americas, but this wasn’t the case this year, according to satellite data. The dense concentration of dust traveled about 8,000 kilometers and can be seen arriving close to the Caribbean and the southern United States.

The ESA’s Copernicus Sentinel-5P satellite, launched in October 2017, maps air pollutants using an instrument that measures the radiation of different wavelengths. Meanwhile, the Aeolus satellite, launched by the ESA in August 2018, tracks wind speed and direction across the globe.

Aeolus is the first satellite to acquire profiles of Earth’s wind on a global scale the satellite also delivers information about the vertical distribution of aerosol and cloud layers. This combination of data allows scientists to improve their understanding of the Saharan Air Layer, and allows forecasters to provide better air quality predictions.

While it can be a threat to our health, triggering air quality alerts, the dust travelling from the Saharan Desert is also very important for ecosystems. Dust is a key source of nutrients for the tiny algae known as phytoplankton that live drift on the surface of the ocean. Minerals from the dust fall in the ocean, triggering blooms of the algae to form on the surface of the ocean – providing food to marine life.

At the same time, the dust is also very important for life in the Amazon region, replenishing nutrients in the rainforest soils which otherwise would be depleted due to the frequent rain in the region. The dusty air layers have also been found to limit the development of hurricanes and storms in the Pacific.

Asian dust fertilizes the ocean with life-supporting nutrients

The vast oceanic gyres (large systems of rotating currents) are thought to be stable and barren. Caused by the Coriolis effect produced by the Earth’s rotation, they cover around a third of the Earth’s surface. They’re also regarded biological deserts, with stratified, nutrient-poor water that just doesn’t favor a thriving ecosystem.

But there’s an exception.

The North Pacific Subtropical Gyre ecosystem features an anomaly which has puzzled oceanographers for years: it changes its chemistry with no clear cause. The new study focused on the North Pacific Subtropical Gyre, using three decades of observation data from Station ALOHA by the Hawaii Ocean Time-series program to characterize this surprising area.

The five major ocean-wide gyres — the North Atlantic, South Atlantic, North Pacific, South Pacific, and Indian Ocean gyres.

Generally speaking, the more mixing takes place in an oceanic environment, the better it is for life. Sunlight passes through the surface parts of the water column, allowing photosynthetic creatures to do their thing, while nutrient-rich layers from the bottom of the sea are brought to the surface as a fertilizer. In the North Pacific gyre, however, that’s not really the case.

The water is strongly stratified because there’s no real mixing taking place. This means that without deeper murky waters brought in the mix, the surface water is exceptionally clear, supporting photosynthetic activity below 100 meters (or 328 feet). But in order for marine life to thrive, it would need elements such as phosphorous and iron, which are lacking in the area.

Or so we thought.

Over the course of three decades, researchers noticed a surprising variation in the chemistry of these waters, as if something was fertilizing them with phosphorous and iron. They traced the source back to Asian dust, coming from small desert particles, forest fires, and even factory output. These particles are carried over large distances by strong winds, ultimately spreading around the gyre and providing nutrients necessary to sustain life.

The supply of nutrients is a fundamental regulator of oceanic wildlife (and carbon sequestration). These ecosystems are governed by nutrient sources and nutrient sinks, and any change in these parameters could have cascading effects on biodiversity. Researchers were surprised to see just how much of an impact the Asian dust has, and how dynamic and unpredictable its input is.

“We now know that these areas that were thought to be barren and stable are actually quite dynamic,” said Ricardo Letelier, an Oregon State University biogeochemist and ecologist, who in collaboration with David Karl at the University of Hawaii led this study. “Since these areas cover so much of the Earth’s surface, we need to know more about how they work in order to better predict how the system will respond to climate variations in the future.”

Asian dust is transported over the North Pacific Ocean. Image credits: NASA.

This pattern isn’t regular, researchers stress, and it’s not exactly clear how the ecosystem copes with this irregularity.

“Sometimes there are periods of 5-6 years of phosphorus enrichment, and then there are periods when it switches over,” Letelier said. “From 2000 to 2007, there was almost no phosphorus. We have seen some changes in the function of the ecosystem, but we haven’t yet seen significant changes in the biological composition. They may be coming; it’s too early to tell.”

There’s another creeping issue affecting this process: human influence. Rising temperatures (which are especially prevalent in the Arctic) mean that global wind circulation will also change, with consequences that are as of now unforeseen. Additionally, pollution is also an unpredictable factor in the mix. How these aspects will affect the transport of iron- and phosphorous-rich dust from Asia to the Pacific remains a question to be answered by further research.

The study has been published in PNAS.

Mars.

Some Martian clouds are made of ground-up meteors

Mars has clouds too — but some are formed by falling meteorites, not rain.

Mars.

Rendering of Mars produced using MOLA altimetry data.
Image credits Kevin Gill / Flickr.

Researchers from the University of Colorado at Boulder have obtained new insight into the clouds that dot the Red Planet. While these clouds have long been documented in Mars’ middle atmosphere (which begins about 18 miles or 30 kilometers above the surface), little was known about how they form in the thin, dry ‘air’ there.

New research shows that these wispy bodies are actually accumulations of “meteoric smoke”, the icy dust thrown up when meteorites or space debris break up in the planet’s atmosphere.

Dust rain

“We’re used to thinking of Earth, Mars and other bodies as these really self-contained planets that determine their own climates,” said Victoria Hartwick, a graduate student in the Department of Atmospheric and Ocean Sciences (ATOC) and lead author of the new study.

“But climate isn’t independent of the surrounding solar system.”

The most peculiar fact about Mars’ clouds is that they exist. The Big Bang notwithstanding, you can’t make something out of nothing, and clouds subscribe to this rule as well. Down here on Earth, low-lying clouds form on the backs of tiny particles — things like grains of sea salt or dust that get blown high into the air. These act as anchors of sorts for water vapor to condense on, growing into larger and larger drops, forming the large puffs of white or gray you can see from the ground.

To the best of our knowledge, however, that same mechanism doesn’t exist on Mars. There’s no sea salt to be blown up, and even if there was, the atmosphere is less dense so it’s less able to hold particles aloft. So Hartwick’s team turned their attention to meteors.

Around two to three tons of space debris rain down on Mars, on average, every single day, the authors explain. As this material, ranging from meteorites to space dust, comes into contact with the planet’s atmosphere, it starts to burn and break apart. In essence, a torrent of space dust ‘rains’ down on Mars.

So far, the theory seemed plausible — now the team needed to test it. To find out if this dust could generate Mars’ mysterious clouds, the team employed massive computer simulations that attempt to mimic the flows and turbulence of the planet’s atmosphere. After introducing meteors into the simulations, clouds started to appear.

“Our model couldn’t form clouds at these altitudes before,” Hartwick said. “But now, they’re all there, and they seem to be in all the right places.”

The findings are supported by previous research showing that a similar mechanism may help seed clouds near Earth’s poles (where the magnetic shield is weakest), the team explains. However, we shouldn’t expect to see enormous, roiling thunderstorms of cosmic dust above Mars: the clouds Hartwick’s team studied are very thin, “cotton candy-like clouds” explains Space.

“But just because they’re thin and you can’t really see them doesn’t mean they can’t have an effect on the dynamics of the climate,” Hartwick said.

Depending on the area, these clouds could cause temperature swings of up to 18 degrees Fahrenheit (10 degrees Celsius), the team’s model shows. The findings flesh out our understanding of Martian clouds and could help us better understand how ancient Mars regulated its climate, and how it was able to hold liquid water on its surface.

The paper “High-altitude water ice cloud formation on Mars controlled by interplanetary dust particles” has been published in the journal Nature Geoscience.

Opportunity dusty.

Rumors of Opportunity’s death “very premature”, despite three-weeks silence

NASA’s last contact with the Opportunity Rover took place over three weeks ago. Despite this, the agency believes it’s too early to assume the worst case scenario — the rover’s demise.

Opportunity dusty.

Opportunity covered in dust on Mars.
Image credits NASA / JPL.

We’ve been talking a lot about the huge dust storm that’s engulfed Mars of late, and of how NASA’s two rovers — Opportunity and Curiosity — are weathering the event. Out of the two, Curiosity has been served the much sweeter side of the dish: powered by a nuclear reactor and sitting out of the storm’s way, it’s been free to leisurely capture pics of the weather (and itself).

The older and solar-powered Opportunity, however, is stuck in the massive storm. Besides getting pelted by dust that may harm its scientific instruments, the rover is also unable to recharge. Dust blocks so much of the incoming sunlight that Opportunity’s solar panels just can’t create a spark. Bereft of battery charge, the rover stands a real chance of freezing to death on — fittingly– Mars’ Perseverance Valley.

Tough as old (ro)boots

Opportunity has been on duty for some 14 years now. It’s a veteran space explorer that relayed treasure troves of data for researchers back here on Earth. I’m rooting for the bot to weather the storm. By this point, however, it’s been three weeks since it last established contact with NASA — enough to make even the most resolute worry about its fate.

Dr. James Rice, co-investigator and geology team leader on NASA projects including Opportunity, says we shouldn’t assume the worst just yet.

Talking with Space Insider, Dr. Rice explains during its last contact with NASA, Opportunity also sent back a power reading. It showed the rover managed to scrape a meager 22 Wh of energy from its solar panels. For context, the rover managed to collect 645 Wh of energy from its panels just ten days before. This chokehold on energy is the NASA’s main concern at the moment.

However, he adds that the same storm which prevents Opportunity from recharging its batteries may ultimately also be its salvation.

One of the reasons NASA was caught offguard by the storm is that they simply don’t generally form around this time of the Martian Year. It’s currently spring on the Red Planet’s Southern Hemisphere, but dust storms usually form during summer. The only other dust event NASA recorded during the Martian Spring formed in 2001, and even that one came significantly later in the season than the current storm.

Mars storm.

The first indications of a dust storm appeared back on May 30. The team was notified, and put together a 3-day plan to get the rover through the weekend. After the weekend the storm was still going, with atmospheric opacity jumping dramatically from day to day.

Still, at least it’s not winter — so average temperatures aren’t that low on Mars right now. The dust further helps keep Opportunity warmer, as it traps heat around the rover.

“We went from generating a healthy 645 watt-hours on June 1 to an unheard of, life-threatening, low just about one week later. Our last power reading on June 10 was only 22 watt hours the lowest we have ever seen” Dr. Rice explained.

“Our thermal experts think that we will stay above those low critical temperatures because we have a Warm Electronics Box (WEB) that is well insulated. So we are not expecting any thermal damage to the batteries or computer systems. Fortunately for us it is also the Martian Spring and the dust, while hindering our solar power in the day, helps keep us warmer at night,” he added.

The storm has reached 15.8 million square miles (41 million square kilometers) in size this June. It poses a real risk to Opportunity’s wellbeing, but ground control remains optimistic. Mars Exploration Program director Jim Watzin believes that the massive storm may have already peaked — but, considering that it took roughly a month for it to build up, it could take a “substantial” amount of time before it dissipates completely.

“As of our latest Opportunity status report Saturday (June 30) this storm shows no sign of abating anytime soon. We had a chance to conduct an uplink last night at the potential low-power fault window. We sent a real-time activate of a beep as we have done over the past two weeks. We had a negative detection of the beep at the expected time,” Dr Rice added.

“A formal listening strategy is in development for the next several months.”

Among all this, or rather also because of all that’s happening to Opportunity, I can’t help but feel genuine admiration for it as well as the people who helped put it together. Opportunity was first launched in 2004 and along its sister craft Spirit, was supposed to perform a 90-day mission. Spirit kept going until 2010, and Opportunity is still going strong today (and hopefully for longer). That’s a level of dedication I can only dream of.

Based in part on the rover’s rugged track record, Dr. Rice believes that “rumors of Opportunity’s death are very premature at this point.”

Curiosity mars.

Mars’ huge dust storm is now a “global” storm

The dust storm battering Opportunity is now a global storm, NASA reports.

Curiosity Mars.

Curiosity approaching Mars in December 2012.
Image credits NASA / JPL-Caltech.

Mars hasn’t been enjoying the fairest weather as of late. A massive dust storm has engulfed Perserverence Valley, pinning NASA’s Opportunity rover in place; all the dust is blocking out sunlight, preventing the bot from recharging its batteries — so much so that ground control fears it might freeze out, as its dwindling power supply can’t feed the rover’s inbuilt heaters.

According to NASA, the weather is only getting worse. The dust storm has grown in size and is inching in even on the Curiosity rover, half a Mars away from the beleaguered Opportunity. The storm has officially become a “planet-encircling” or “global” dust event.

Mars Stormborn

NASA reports that dust is rapidly and steadily settling down on Curiosity. The quantity of dust settling on the rover has more than doubled over the weekend, they note. The storm’s light-blocking factor, or “tau”, has grown to over 8.0 above Gale Crater (where Curiosity is currently rovering about) — the highest value the bot has ever recorded during its mission. For context, Opportunity is experiencing 11 tau, a value high enough to prevent its instruments from making any accurate measurements.

However, NASA is confident Curiosity will remain unaffected by the grime. Unlike its cousin, it draws power from a nuclear reactor, so the lack of light isn’t really a big issue. Curiosity’s cameras are having a hard time, however, as the lack of light means it has to use long exposure times. NASA is having it point its cameras down at the ground after each use to reduce the amount of dust blowing at its lenses.

However, there’s a silver lining. Because Curiosity can keep functioning in the storm, NASA hopes to use the rover to understand the phenomenon better. One of the main questions they want to answer is why some Martian dust storms remain small and stall before a week has passed, while others grow and grow and last for months.

“We don’t have any good idea,” said Scott D. Guzewich, an atmospheric scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, leading Curiosity’s dust storm investigation.

Together with the craft in orbit around Mars, Curiosity will collect data on the storm to help patch up our understanding.

Mars dust storm.

This animation, pieced together from pictures taken by Curiosity’s Mast Camera, shows the weather darkening over Mars. The rover is currently standing inside Gale Crater, and peeking its camera over its rim. The photos were taken over a few weeks, with the first one snapped before the storm appeared.
Image credits NASA.

The images above were taken roughly 30 kilometers (18.6 miles) away from the storm. The haze is about six to eight times thicker than what’s usual for this time of the Martian year, NASA estimates.

Dust storms on Mars are actually quite commonplace. Surprising for a dusty planet, I know. They’re especially frequent in the southern hemisphere during both spring and summer months (Mars’, not the ones on Earth). These are the months during which Mars is closest to the Sun, and the temperature imbalances in the atmosphere generate winds that mobilize dust grains (this dust is about as fine as talcum powder). Carbon dioxide ice (dry ice) embedded in the planet’s polar ice caps also evaporates during these months, making the atmosphere extra-thick — this increased pressure helps suspend dust in the air. Dust clouds have been spotted up to 60 kilometers (40 miles) high.

However, Martian dust storms don’t usually cause a ruckus. They tend to hang out in a confined area and dissipate within a week. By contrast, the current storm is bigger than North America and Russia combined, according to Guzewich. It’s even more impressive when you consider the size of Mars relative to Earth:

Mars-Earth.

Mars (diameter 6790 kilometers) is only slightly more than half the size of Earth (diameter 12750 kilometers). The image shows the true relative size between the two planets.
Image credits Viking Orbiter Views of Mars, NASA SP-441, p. 14.

The size difference is one of the elements that allows Martian dust storms to grow to such immense sizes. Earth’s gravitational pull is almost double that of Mars, which helps settle the dust. Vegetation also binds the soil, preventing particles from getting airborne, and rain washes whatever gets in the atmosphere back down.

Opportunity.

Opportunity braves the worst sand storm it’s ever faced, might not make it

Shoutout to the Opportunity rover for signaling home amid the worst Martian sandstorm it’s ever faced.

Mars map.

This global map of Mars shows a growing dust storm as of June 6, 2018. The map was produced by the Mars Color Imager (MARCI) camera on NASA’s Mars Reconnaissance Orbiter spacecraft. The blue dot indicates the approximate location of Opportunity.
Image and caption credits NASA/JPL-Caltech/MSSS.

On Sunday morning, NASA received a transmission from the Opportunity rover. Usually, that’s not really out of its character — but the bot is currently braving a massive sandstorm on the Red Planet. The rover hailed home to let ground control know it still has enough juice in its battery to maintain communications, according to NASA. Science operations, however, remain suspended in a bid to conserve energy.

Oppy phone home

The transmission was a welcome break for NASA engineers, as the dust storm has been steadily picking up steam in the past few days. The rover is weathering it out in Perseverance Valley, shrouded in perpetual night. NASA’s Mars Reconnaissance Orbiter first detected the storm on Friday, June 1. The rover team began preparing contingency plans soon afterward.

It’s not the first such storm Opportunity had to face — it braved another in 2007. This event, however, is much worse than the last one. The storm’s atmospheric opacity (how much light it blocks) has been estimated at 10.8 tau as of Sunday morning — the 2007 storm only reached about 5.5 tau. This is roughly equivalent to the incredible smogs we’ve seen in China. Because of this, the bot cannot use its solar panels to recharge.

The storm has grown to over 18 million square kilometers (7 million square miles) since its detection. Such storms aren’t extreme for Mars, but they are infrequent. NASA doesn’t yet fully understand how they form or build in strength, but they seem to be self-reinforcing — a feedback loop that amplifies itself as it grows. Such storms can last up to several months at a time.

This dust blanket could be what makes or breaks Opportunity’s resolve.

Dusty but not yet dead

Opportunity.

You could say it’s an Opportunity to show what you’re made of, little rover!
Image credits NASA/JPL-Caltech/Cornell Univ./Arizona State Univ.

I say that because the dust is both a boon and a curse for Opportunity as of now. The rover’s main problems are that it cannot recharge (its solar panels are dusted over, and there’s not enough sunlight) and that communication with ground control is spotty at best (radio signals can’t pierce through the storm).

But the dust also hides a silver lining. Data beamed back by the rover shows its internal temperature is roughly stable at about minus 29 degrees Celsius (minus 20 Fahrenheit). The dust storm — which retains heat — seems to be insulating Opportunity from the extreme temperature swings on Mars’ surface. It’s not an ideal temperature by any means, but it’s still not as bad as it could get.

The team’s worst fears right now is that if the rover experiences cold temperatures for too long, it might damage its batteries. This fate befell Spirit, Opportunity’s twin craft in the Mars Exploration Rover mission, in 2010. Engineers plan to use the network to monitor and administer the rover’s energy levels in the following weeks — they need to somehow save as much battery charge as possible while keeping the rover from getting too cold. It has onboard heaters for this purpose, but they drain a lot of energy. One idea the team is considering is activating other equipment to expel energy, which would heat up the bot.

Science operations have been temporarily put on hold for sunnier days. Mission control has requested additional coverage from NASA’s Deep Space Network, a global system of antennas that talks to all the agency’s deep space probes, in an effort to maintain contact with Opportunity.

But I wouldn’t count Opportunity out just yet. It has proved its mettle aplenty in the past. Not only has it gone through dust storms before, but it made it with surprising gusto — the rover has accrued 15 years in the line of duty despite only being intended to last 90 days.

So hang in there little buddy, and don’t let the cold bite your batteries.

Artist impression of an early solar system. Credit: NASA.

Scientists collect interstellar dust that formed the Earth and solar system

Researchers have discovered an enormous body of interstellar dust that predates the formation of our solar system 4.6 billion years ago. The findings might revolutionize our understanding of how the solar system came to be, as well as all other planetary bodies.

Artist impression of an early solar system. Credit: NASA.

Artist impression of an early solar system. Credit: NASA.

It sounds unbelievable, but some of the original interstellar dust that went to form the sun, Earth, and all the other planets in the solar system can be still be found floating around in our neighborhood, even hitting our atmosphere from time to time. Presolar dust particles can no longer be found in the inner solar system, as it was long ago destroyed, reformed, and reaggregated in multiple phases. However, presolar dust can still be found in the outer solar system, specifically in some comets.

When these comets pass close enough to the sun, they release presolar dust that can reach Earth’s orbit and settle through the atmosphere, where it can be collected and later studied. Dr. Hope Ishii of the University of Hawai’i at Manoa and her colleagues used electron microscopy to study such dust particles, as well as data gathered from the Cosmic Dust Analyzer (CDA) aboard the Cassini Saturn orbiter during its two-decade mission.

The presolar dust particles in question are actually called GEMS – or ‘glass embedded with metal and sulfide’. They’re less than one hundredth the width of a human hair in diameter and contain a variety of carbon known to decompose when exposed to even relatively gentle heating.

An electron micrograph of an interplanetary dust particle of likely cometary origin. Credit: Hope Ishii

Ishii and colleagues write that the GEMS likely formed in the interstellar medium due to grain shattering, amorphization, and erosion from supernovae shocks, then later went through subsequent periods of aggregation. Irradiation likely provided enough energy for the amorphous silicates which comprise the dust to absorb small amounts of metal atoms, the authors reported in the journal Proceedings of the National Academy of Sciences. 

“With repeated cycling in and out of cold molecular clouds, mantled dust and any aggregates were repeatedly and progressively partially destroyed and reformed. Cassini mission data suggest the presence of iron metal in contemporary interstellar dust,” the researchers wrote in their study.

This first generation of GEMS aggregated with crystalline grains that were likely transported from the hot inner-solar nebula, creating second-generation aggregates. Later this 2nd generation of aggregates was likely incorporated into small, icy cometary bodies.

The researchers concluded that the grains they studied represent surviving pre-solar interstellar dust that formed the very building blocks of planets and stars. As such, they provide unique insight into a pre-solar system environment, ultimately telling us how our planet and others like it came to be. We only have a rough picture of how our solar system formed from a huge disk of dust and gas, and these little grains could be the missing pieces that complete the puzzle. In the future, the researchers plan on collecting more comet dust, particularly that sourced from more well-protected comets that pass by the sun.

Moon footprint.

Mock lunar dust kills cultured cells, alters DNA — raising concerns about the real thing’s toxicity

Don’t forget to dust off your spacesuit if you go trekking out on the Moon — else you might risk cellular and DNA damage.

Moon footprint.

Footprint made by Buzz Aldrin during the Apollo 11 mission.
Image credits NASA.

A new study has revealed one more thing we’ll have to plan for when and if we decide to settle on the moon: lunar dust can be quite harmful if inhaled. While this isn’t the first signs we’ve seen of moon dust causing trouble for humans — Apollo mission astronauts complained of sneezing and watery eyes after bringing the stuff into their ships on spacesuits — this is the most thorough look at the health risk it poses.

Dust out

“Very small particles in the breathable range or smaller can interact directly with cells,” Bruce Demple, a professor at the Stony Brook University School of Medicine and the study’s corresponding author told Gizmodo.

The study, unfortunately, didn’t involve sending anyone to the Moon. Instead, the team cultivated human lung and mouse brain cells in Petri dishes in a lab, then exposed them to simulated lunar dust. The team reports that the substitute could damage or outright kill cells, as well as compromise the integrity of their genetic material. Up to 90% of human lung cells and mouse neurons died when exposed to dust particles that mimic soils found on the Moon’s surface.

The dust was especially dangerous to living tissue when crushed down into small, micrometer-sized bits.

One interesting find is that it’s not the dust’s chemical interactions with cells — which the team gauged by its ability to generate free radicals — that caused the damage. They’re not exactly sure what does, however. Demple suspects the way these dust particles are shaped might have something to do with it. Past research has looked into using physical rather than biochemical defenses against bacteria, and some animals also sport similar defenses, so Demple’s theory isn’t as far-fetched as it may first seem.

Moon-dust-montage.

Pieces of moon dust under the microscope.
Image credits NIST.

All in all, though, it’s not the best of news. Moon dust is much drier than the one we’re used to seeing down here and likely to be electrostatically charged, on account of there being no atmosphere, the paper notes. Last but not least, it’s also likely composed of much tinier particles — ground down by billions of years of meteorite bombardments. In other words, lunar dust has a tendency to be drawn to and stick to everything. It’s also tiny enough to bypass most filters and be a nuisance for some seals. Together, these properties would make dusting off spacesuits and equipment an exercise in frustration.

Given how dangerous this dust may be to living cells, this might become quite a health hazard for potential lunar colonists. The team reports that long exposure to the dust could lead to bronchitis or other health problems. The hay-fever-like symptoms the Apollo astronauts experienced suggests that longer exposure to the dust could impair airway and lung function, Demple explains. If the dust also causes inflammation in the lungs, it could increase the risks of diseases such as cancer.

“If there are trips back to the Moon that involve stays of weeks, months or even longer, it probably won’t be possible to eliminate that risk completely,” Demple adds.

Still, the results aren’t conclusive as of now. The study itself is quite limited since it used a moon dust substitute, as the original wasn’t available and quite hard to reach. Cultured cells are also a poor substitute for the complexity of a whole, living organism. However, it does suggest that dust from the moon could pose a serious threat to health, a finding that is supported by previous research. Dismissing the findings outright based on the study’s limitations would thus be quite foolish.

The team is fully aware of these shortcomings, but they hope that the results will convince NASA to let them work with real lunar dust, recovered by the Apollo missions.

The paper “Assessing Toxicity and Nuclear and Mitochondrial DNA Damage Caused by Exposure of Mammalian Cells to Lunar Regolith Simulants” has been published in the journal GeoHealth.

“Apocalyptic” Red Sun phenomenon in UK triggered by Hurricane Ophelia, forest fires, and dust from the Sahara

Unusually red-looking Sun sightings are being reported across the UK as darkness and sepia tones have taken over the country. The cause, meteorologists say, is a hurricane dragging in tropical dust from Sahara.

Image via Birmingham Updates / Facebook.

If you’d happen to be in many parts of the UK today, you’d likely be facing a desolate landscape. It’s dark, windy, raining in most parts, and the Sun looks like a creepy blood-red circle. This visual phenomenon is especially prevalent in the South West, West Midlands, North West and North East. It’s associated with Hurricane Ophelia, though in itself it’s no cause for concern.

What happened is that the gusts of air picked up dust and soil pieces from the Sahara and brought them along to the British islands; once in the air, these particles refract and reflect light, resulting in longer wavelengths, towards the reddish part of the spectrum. But that only tells half of the story — or even less. The Met Office said the “vast majority” of dust particles came from the massive forest firest suffered by Spain and Portugal earlier this year.

At this point, it’s not clear if the danger posed by Ophelia has passed.

While there’s no need to worry due to the red Sun, the hurricane itself is a completely different problem. Ireland’s west coast has been severely hit and at least one woman was killed after a tree fell on her car. Authorities have warned everyone in affected areas to remain indoors until the storm passes.

It’s uncommon for Atlantic hurricanes to head eastward, towards Britain. Hurricane Ophelia was the easternmost Atlantic major hurricane on record, already causing serious damage in Ireland and parts of the UK. With highest sustained winds of 115 mph (185 km/h), it affected the Portuguese Azores Islands before moving north towards Britain.

 

Dust solar panel.

Dusty solar panels slash power output by over 35%, study reveales

Grit and grime can cut solar panels’ output by more than 35% in certain areas of the globe, a new paper reports.

Dusty Window.

Image via Pixabay.

Cleanliness may be next to godliness, but more to the point, it’s just good business. That’s according to the results of a new study led by Duke University professor of engineering Michael Bergin, who looked at the impact dust and other types of air pollutants have on the output of solar panels. The findings show that the accumulation of airborne particles (both in the shape of dust and anthropic pollution) on solar cells can grind their output down by more than 25% in certain regions. The most affected countries are also those who are investing most heavily in solar energy, such as China, India, and countries in the Arabian Peninsula.

[button url=”https://lp.understandsolar.com/ro/core/?lead_source=zmescience&tracking_code=dusty_solar” postid=”” style=”btn-success” size=”btn-lg” target=”_blank” fullwidth=”true”]Find out how much a solar roof can save you in your area[/button]

Dusty

Working with researchers at the Indian Institute of Technology-Gandhinagar (IITGN) and the University of Wisconsin at Madison, Bergin measured the drop in power output in IITGN’s solar panels over time, as they built up dust and dirt.

“My colleagues in India were showing off some of their rooftop solar installations, and I was blown away by how dirty the panels were,” professor Bergin said.

“I thought the dirt had to affect their efficiencies, but there weren’t any studies out there estimating the losses. So we put together a comprehensive model to do just that.”

The numbers showed that cleaning the panels after a few weeks of getting dirty would lead to a 50% increase in their efficiency. The team also sampled the grime layer to see what it was made of. Analysis revealed that some 92% of particles were regular, run of the mill dust, with the rest being composed of anthropic-sourced carbon and ion pollutants. The latter, despite making up only 8% of the whole, are much more powerful at blocking sunlight that natural dust. All in all, the team estimates, human contribution in solar cell energy loss roughly equal to that of natural pollutants. Anthropic particles are also smaller and stickier, making them difficult to clean off, and potentially posing a risk for the panels’ proper functioning.

“You might think you could just clean the solar panels more often, but the more you clean them, the higher your risk of damaging them.”

Dirt and grime aren’t the only things slashing solar efficiency, however. To assess the part atmosphere-borne particles play in blocking sunlight from reaching the cells, the team worked with Drew Shindell, professor of climate sciences at Duke and an expert in using the NASA GISS Global Climate Model. Starting from the model, which accounts for airborne-particle reflection of incoming solar energy, he could estimate how much light they would prevent from reaching the panels. The NASA model also estimates the amount of particulate matter deposited on surfaces worldwide, offering a handy avenue for the team to calculate how much sunlight would be blocked by accumulated dust and pollution.

Dust solar panel.

Professor Michael Bergin (left) Indian Institute of Technology-Gandhinagar colleague Chinmay Ghoroi (right) next to that university’s extremely dusty solar panel array.
Image credits Bergin et al., 2017.

Finally, Bergin drew on his previous research of analyzing how pollutants are discoloring India’s Taj Mahal to put together a model that describes how much sunlight gets blocked by different compositions of solar panel dust and pollution buildup. This model can be used to estimate the total loss of solar energy output in any part of the world.

[button url=”https://lp.understandsolar.com/ro/core/?lead_source=zmescience&tracking_code=dusty_solar” postid=”” style=”btn-success” size=”btn-lg” target=”_blank” fullwidth=”true”]Find out how much a solar roof can save you in your area[/button]

For example, the US has relatively little dust and sees only small reductions in power due to dusty build-ups. By contrast, more arid regions such as the Arabian Peninsula, Northern India, and Eastern China can see heavy losses: 17% to 25% or even more, if cleaning is only performed on a monthly basis. For one cleaning per every two months, losses can jump to 25%, even edging over 35%. These numbers can certainly be influenced by local or regional factors which the paper can’t foresee. A nearby building site, for example, would create a large quantity of airborne and deposited particles for a solar array.

The composition also matters, and its effects vary from place to place. The Arabian Peninsula, the team writes, loses much more output to dust than to anthropic pollutants. Some regions of China and of India, however, see more losses due to the latter.

“China is already looking at tens of billions of dollars being lost each year, with more than 80 percent of that coming from losses due to pollution,” said Bergin. “With the explosion of renewables taking place in China and their recent commitment to expanding their solar power capacity, that number is only going to go up.”

“We always knew these pollutants were bad for human health and climate change, but now we’ve shown how bad they are for solar energy as well,” he added. “It’s yet another reason for policymakers worldwide to adopt emissions controls.”

The paper “Large Reductions in Solar Energy Production Due to Dust and Particulate Air Pollution” has been published in the journal Environmental Science & Technology Letters.

Finger sensor

Dust-sized sensors might one day monitor brain nerves. No batteries required

Finger sensor

The dust-sized sensor is so small it’s on scale with fingerprints. Credit: Ryan Neely

The first dust-sized sensors were recently demonstrated by a team from UC Berkeley, United States. These can be implanted in the human body to relay back vital signs or even trigger actions. Scientists claim the battery-free neural dust motes can monitor internal nerves, muscles or organs — all in real time.

As far as internal body sensors are concerned, one of the prerequisites is to make them as small as possible. For some applications, like neural sensors, these sensors have to be even smaller than the diameter of a blood vessel. There’s only so much you can get away with miniaturization, though.

A sensor typically needs a battery to power it or some sort of power supply, an antenna to transmit and receive information, circuitry, not to mention the actual sensing electronic instruments. When faced with this sort of challenges, it really boils down to solving the weakest link in the chain — namely cut down on the most voluminous component of your sensor. In most cases, this is the power supply.

The UC Berkeley managed to scrap batteries altogether by using a piezoelectric crystal that converts ultrasound vibrations from outside the body into electricity to power a tiny, onboard transistor. The same physical phenomenon is being exploited in California to generate electricity from cars driving over highways.

Ultrasound pulses both power and read out measurements. . The backscatter signal carries information about the voltage across the sensor’s two electrodes. Credit: UC Berkeley

Ultrasound pulses both power and read out measurements. . The backscatter signal carries information about the voltage across the sensor’s two electrodes. Credit: UC Berkeley

The transistor is in contact with biological tissue, say a nerve or muscle, and when the ultrasounds cause it to spike a voltage, the biological fiber alters the piezoelectric crystal’s vibration. This vibration changes the ultrasound echo which is picked up by a receiver, typically the same device that generates the initial ultrasound pulse in the first place. So, the ultrasounds both power and read out the measurements — very clever! Ultrasounds are also more efficient than radio waves, the UC Berkeley researchers claim.

This is how scientists were able to monitor the muscles and peripheral nerves of rats: with these tiny motes measuring only one cubic millimeter. The passive sensors were powered up every 100 microseconds with six 540-nanosecond ultrasound pulses.

For this particular experiment, the team covered the motes with surgical-grade epoxy, but the next version will be coated with biological compatible films. They also want to make the sensors — currently the size of a grain of sand — even smaller. The goal is to make them no larger than 50 microns on a side or half the width of a human hair. At this scale, the specks could be small enough to nestle up to nerve axons and record their activity.

The sensor, 3 millimeters long and 1×1 millimeters in cross section, attached to a nerve fiber in a rat. Credit: University of California, Berkeley

The sensor, 3 millimeters long and 1×1 millimeters in cross section, attached to a nerve fiber in a rat. Credit: University of California, Berkeley

One of the most promising application is in brain-computer interfaces, such as the ones currently being experimented to help paraplegics control prostheses with their thoughts, just like the biological counterparts. Although great progress can be made with non-invasive devices like electroencephalogram caps, the best results are achieved with electrodes that have to be implanted straight in the brain. This, of course, involves drilling the skull. Moreover, these electrodes wear out after only one to two years.

Such electronic motes could also be highly useful as electroceutical devices — special gear used in therapy for epilepsy or to stimulate the immune system or tamp down inflammation.

“The original goal of the neural dust project was to imagine the next generation of brain-machine interfaces, and to make it a viable clinical technology,” said neuroscience graduate student Ryan Neely. “If a paraplegic wants to control a computer or a robotic arm, you would just implant this electrode in the brain and it would last essentially a lifetime.”

“The beauty is that now, the sensors are small enough to have a good application in the peripheral nervous system, for bladder control or appetite suppression, for example,“ Carmena said. “The technology is not really there yet to get to the 50-micron target size, which we would need for the brain and central nervous system. Once it’s clinically proven, however, neural dust will just replace wire electrodes. This time, once you close up the brain, you’re done.“

The findings appeared in the Neuron Journal.

 

NASA snaps beautiful picture of Mars as it inches over towards Earth

NASA astronomers captured a beautiful image of Mars on May 12, when the planet was just 50 million miles away from Earth. Bright snow-capped polar regions and rolling clouds above the rusty landscape show that Mars is a dynamic, seasonal planet, not an inert rock barreling through space.

This picture was taken just a few days before the Mars opposition on May 22, when the red planet and the sun will be on exact opposite side of the Earth. Mars circles around the sun on an elliptical orbit, and its approaches to Earth range from 35 to 63 million miles. From now to May 30 Mars will inch in ever closer to 46.8 million miles from us — the closest this planet has been to Earth for the last 11 years. Being illuminated directly by the sun, Mars is especially photogenic and NASA used this opportunity to capture a beautiful shot of the planet.

The most eye-catching features are the thick blankets of clouds, clinging to the planet’s thin atmosphere. They can be seen covering large parts of the planet, including the southern polar cap. The western limbs are early morning clouds and haze, while the eastern part is an afternoon cloud extending for more than 1,000 miles at mid-northern latitudes. The northern polar cap is barely visible, as it’s now late summer in that hemisphere.
Mars Near 2016 Oppostion (Annotated)

The overcast Syrtis Major Planitia is an ancient shield volcano, now inactive. It was one of the first structures charted on the planet’s surface by seventeenth century observers. Huygens used this feature as a reference point to calculate the rotation speed of Mars — one day on the red planet clocking in at 24 hours and 37 minutes.

Hellas Planitia basin extends to the south of Syrtis Major. At about 1,100 miles across and nearly five miles deep, you’d think it’s a tectonic depression, but it was actually formed 3.5 billion years ago when a huge asteroid crashed into Mars. The planet had its fair share of meteorite impacts throughout the ages, as Arabia Terra can attest — this 2,800 mile upland region is dotted with craters and heavily eroded. Dry river canyons wind through the region, testament to rivers that once flowed into the large northern lowlands.

The long, dark ridges running along the equator south of Arabia Terra, are known as Sinus Sabaeus (to the east, not pictured) and Sinus Meridiani (to the west). These areas are covered by dark bedrock and sand ground down from ancient lava flows and other volcanic features. The sand is coarser and less reflective than the fine dust enveloping the planet, making them stand out.

Several NASA Mars robotic missions, including Viking 1 (1976), Mars Pathfinder (1997) and the still-operating Opportunity Mars rover have landed on the hemisphere visible in this picture. Spirit and Curiosity Mars rovers landed on the opposite side of the planet.

All images provided by Hubble Site.

What comet dust looks like, courtesy of ESA’s Rosetta mission

Millions of miles afar, comets dot the night’s sky leaving an unmistakable trail of dust, gas and ice. In 2014, Rosetta’s Philae probe landed on a comet — a monumental achievement in space exploration — documenting the inner workings, chemical composition and structure of these fascinating cosmic bodies. Among others, we now know the 67P/Churyumov–Gerasimenko comet has sinkholes or holds primordial oxygen. Now, researchers revealed a more familiar curiosity: what dust particles on a comet look like.

Diversity of particles seen on a small area on one single target. This image section measures 2.5 mm across, with light coming from the right. Examples of a compact particle (a), a shattered cluster (b), a glued cluster (c) and a large rubble pile (d) are seen in this small area. Image: ESA

Diversity of particles seen on a small area on one single target. This image section measures 2.5 mm across, with light coming from the right. Examples of a compact particle (a), a shattered cluster (b), a glued cluster (c) and a large rubble pile (d) are seen in this small area. Image: ESA

Dust grains were collected between 1 August 2014 – 3 April 2015 across nine 1 cm^2 targets and analyzed using the COSIMA instrument onboard Rosetta. The team led by Yves Langevin of the Institut d’Astrophysique Spatiale at CNRS/University of Paris-Sud, France, characterized the grains by appearance complexity and particle strength.

These images reveal particles from the comet are very diverse in scales ranging from a few  10s of micrometers (μm) to several 100 μm.  In general, the dust families can be divided into compact particles or clusters, with the cluster group further subdivided into shattered clusters, glued clusters and rubble piles.

Compact particles are defined as those with well-defined boundaries, more-often-than-not found without any related smaller ‘satellite’ particles. Credit: ESA

Compact particles are defined as those with well-defined boundaries, more-often-than-not found without any related smaller ‘satellite’ particles. Credit: ESA

Shattered cluster Estelle, one of the most tightly-packed shattered clusters identified. It has three major components plus many minor components. The right hand image is the 3D anaglyph. Credit: ESA

Shattered cluster Estelle, one of the most tightly-packed shattered clusters identified. It has three major components plus many minor components. The right hand image is the 3D anaglyph. Credit: ESA

Glued clusters comprise relatively well-defined particles with an overall complex structure including sub-components which appear to be linked together by a fine-grained matrix, giving the appearance of a smooth surface texture.  Credit: ESA

Glued clusters comprise relatively well-defined particles with an overall complex structure including sub-components which appear to be linked together by a fine-grained matrix, giving the appearance of a smooth surface texture. Credit: ESA

Reference: Typology of dust particles collected by the COSIMA mass spectrometer in the inner coma of 67P/Churyumov-Gerasimenko” by Y. Langevin et al is published in the journal Icarus.

Making your bed every day might encourage mites to breed in it

There are two kinds of people in this world: those who religiously make their bed every day in cleanliness and order… and the rest of us. If you’re in the latter group, then I’ve got some good news: keeping your bed messy might be good for your health.

Image via Nutritious Life.

Mites are everywhere – in every single house. At any given point, there’s probably over one million mites on every bed. House dust mites feed on organic detritus, such as flakes of shed human skin, and flourish in house environments. They’re also a common cause of asthma and allergic symptoms worldwide, because their gut contains potent digestive enzymes that persist in their feces and get ejected into the air and on flat surfaces. Most people are completely immune to their effects, but for some people, these enzymes can trigger asthma and wheezing, as well as a broad range of allergies.

The research was conducted by a team from the Kingston University in England; they used a computer model to predict how the dust mites fare in a range of different conditions – including on a made and non-made bed. They found that the mites flourish on neatly mate beds, but shrivel and dry otherwise.

“We know that mites can only survive by taking in water from the atmosphere using small glands on the outside of their body,” lead researcher Stephen Pretlove told the BBC when the research was released. “Something as simple as leaving a bed unmade during the day can remove moisture from the sheets and mattress so the mites will dehydrate and eventually die.”

A scanning electron micrograph of a female dust mite. Image via Wikipedia.

It has to be said that the model was based on conditions in the UK, and likely doesn’t stand in tropical or much more humid climates. The team also plans to conduct a study on a real life scenario to see if the results are similar to their model.

However, not everyone is convinced that making your bed helps mites.

“It is true that mites need humid conditions to thrive and cannot survive in very dry (desert like) conditions,” Andrew Wardlaw from the British Society for Allergy and Clinical Immunology, who wasn’t involved in the research, told the BBC. “However, most homes in the UK are sufficiently humid for the mites to do well and I find it hard to believe that simply not making your bed would have any impact on the overall humidity.”

I’m hoping that soon they will prove that not making your bed is indeed detrimental to mites… or, you know, any reason to not make your bed.

Journal Reference: David Crowther , Toby Wilkinson, Phillip Biddulph, Tadj Oreszczyn, Stephen Pretlove, Ian Ridley. A simple model for predicting the effect of hygrothermal conditions on populations of house dust mite Dermatophagoides pteronyssinus (Acari: Pyroglyphidae). Experimental & Applied Acarology, DOI10.1007/s10493-006-9003-8 (via Science Alert)

home-dust

How many germs you can find in your home: about 9,000 different species

After they analyzed dust samples collected from 1,200 US households, researchers at University of Colorado at Boulder identified over 9,000 different species of microbes, bacteria and fungus. The exact makeup depends on where the home is located, the gender of the people living inside and whether or not pets are present.

home-dust

Image: Red Beacon

What if I told you there were germs cramming every inch of your home? Most people are already aware of this, thankfully. Others freak out, partly because they might not understand that’s it perfectly natural this way. You weren’t affected by the germs until your heard the news, and you shouldn’t be after you find out. Nevertheless, there have been countless studies that document the germs living inside your home. This is, however, the most extensive by far revealing the extent of the biological makeup that comprises a typical American home.

The research is also another success story of citizen science coming to the rescue, as all the samples were collected by regular folks who then mailed them to the university. About 1,200 households responded to the call and sent dust collected from obscure locations people never usually bother cleaning, like the ledges above the door. The participants also filled out a questionnaire which asked what were their living and household habits, whether or not they were vegetarian, had pets and so on.

Some of the key findings:

  • The average American household has more than 2,000 different species of fungus and 7,000 species of bacteria.
  • Some of the fungus species include common strains like Aspergillus, Penicillium, Alternaria and Fusarium. 
  • Most of the fungus comes from outside the home so the fungus makeup of a home depends on where this is located.
  • Distinct bacteria were found in homes where only women or men lived. That’s because some types of bacteria are more common in women than men, and vice-versa. For instance, in male-dominant homes scientists found two types of skin-dwelling bacteria belonging to the genuses Corynebacterium and Dermabacter, as well as the fecal-associated genus Roseburia, in greater abundance than in female-dominant homes. The researchers attribute the difference in hygiene habits.
  • Having a dog or cat for a pet significantly altered the bacteria makeup of a home. In fact, having pets was the most influential factor that determine the biological ecosystem of your home. The researchers could determine whether or not dogs or cats lived in a home with an accuracy of 92% and 83%, respectively.

The researchers say that most of these microorganisms and fungi they identified are harmless.

“People do not need to worry about microbes in their home. They are all around us, they are on our skin, they’re all around our home – and most of these are completely harmless.

“It is just a fact of life that we are surrounded by these microbes,” concludes Dr Noah Fierer, associate professor of ecology and evolutionary biology at University of Colorado at Boulder.

 

The Moon is shrouded by a dust cloud, and a mystery still stands

The Moon doesn’t have an atmosphere, but it is surrounded by a thick dust cloud; the dust constantly falls down to the lunar surface, but new dust constantly jumps to replenish it. The pattern of dust falling back to its home “in due time … will fill in craters,” says the University of Colorado, Boulder’s Mihaly Horanyi, who led the team that found the dust cloud. “Eventually this will erase the footprints of the astronauts.” But why is this happening?

Image via John Lonsdale.

Some astronomers believe this happens due to the the “steady rain” of particles that impact the lunar surface, constantly scattering new dust onto the surface. But these are not clouds like the ones on Earth – they aren’t even visible if direct light doesn’t shine on them. They also get much more dense when the Earth-Moon system passes through debris left in the wake of a comet.

“The Geminid meteor shower generates shooting stars on Earth, but they can’t do that on the moon,” said Mihaly Horanyi, a physicist at the University of Colorado, Boulder, and the first author on the paper. “They hit the surface on the moon and increase the dust density for a few days.”

In a way, it’s like a car splashing bugs on the windshield. Rick Elphic, a LADEE project scientist who was unaffiliated with the study said:

“The Earth/moon system orbits the sun with an average speed of 67,000 miles per hour, and like bugs on a car windshield, the interplanetary micrometeoroid materials smack into the ‘upstream’ side of the Earth and moon,” Elphic reportedly said. “On Earth these cause meteors, which burn up in the atmosphere, but with the almost negligible atmosphere on the moon, these particles smash right into the lunar surface with tremendous speed.”

These impacts cause the dust to raise at 125 miles above the moon’s surface, but it doesn’t send the dust high enough or fast enough to escape the moon’s gravity.

“This is day in and day out,” Horanyi said. “It is continuously ongoing. Every impact is just a little speck of dust being replaced, but eventually, this process will erase the footprints of the first astronauts to step on the moon.”

Researchers also note that the cloud is not symmetrical, due to the nature of the collisions.

“The lopsided part was kind of a surprise from nature,” said Jamey Szalay, a fourth-year graduate student at the University of Colorado, Boulder, who worked on the study.

(Photo: © Bloomsbury Auctions)

As they were figuring all these out, astronomers remembered that Apollo astronauts orbiting the moon in the 1960s and 70s saw a glow along the horizon just before sunrise, which at the time made scientists believe that the glow was created by dust. This new study confirms that theory, but still doesn’t explain the glow the astronauts reported.

“We have found no evidence of the high density small particle population that could have explained the Apollo reports,” Horanyi said.

New answers, and new questions emerge alike; the moon is still a mysterious, attractive place.

The most exotic material on the planet: researchers find dust from beyond the solar system

Seven particles of dust brought back to Earth by a spacecraft nearly a decade ago appear originate from beyond our solar system. The exotic dust was identified by researchers with the help of 30,000 worldwide citizens.

An optical microscope image of a track through aerogel made by Orion, one of the dust particles believed to be from interstellar space. Photograph: D Frank/Nasa/JSC

The material was collected by the Stardust spacecraft, a 300-kilogram robotic space probe launched by NASA on February 7, 1999. Its primary mission was to collect dust samples from the coma of comet Wild 2, as well as samples of cosmic dust, and return these to Earth for analysis. It was the first such spacecraft of its kind. It featured detectors which worked like cosmic fly-paper, gathering as much dust as possible. In 2006, the shuttle parachuted the detectors onto Earth, where they started to be analyzed.

The specks have all the hallmarks of being created in interstellar space. If the analysis is confirmed, it would be the first time interstellar particles are brought back to Earth to be studied. The dust was probably created by a supernova explosion millions of years ago and shaped by exposure to the harsh extremes of space.

“These are very precious particles,” said Andrew Westphal, a physicist at the University of California in Berkeley, who worked on the dust.

Virtually everything we know about interstellar matter, either ground based, or with space telescopes; studying it directly could provide valuable insights.

 “We seem to be getting our first glimpse of the surprising diversity of interstellar dust particles, which is impossible to explore through astronomical observations alone,” Westphal added.

Aside for these exotic particles, researchers found  more than 50 other particles of spacecraft debris in the Stardust detectors, according to a report published in ScienceAnton Kearsley, a microanalyst who took part in the study at the Natural History Museum in London, says that identifying them is a huge challenge:

“In the end, 30,000 people around the world worked through thousands of digital microscope images of the main part of the collector, the aerogel, and eventually found the tracks that included interstellar dust particles,” he said.

“As the results came in, the numbers and sizes of dust grains were not what we’d expected, and many seemed to have come from strange directions,” he added. “Only by careful plotting of impact directions was the team able to identify the seven particles that must have come from outside the solar system.”

Dead human skin gathered in dust is good for the air

Ironically, while most tidy people in the world are busy dusting off furniture, electronics, ceilings, cats, whatnot, researchers have shown in a  recent study that the same dust is actually very good for the air, reducing ozone levels by 2 to 15 percent. All because of dead human skin.

Ozone is crucial for preventing potentially damaging electromagnetic radiation from reaching the Earth’s surface, but in the lower atmosphere, say ground level, it acts as an air pollutant with harmful effects on the respiratory systems of animals and will burn sensitive plants.

Squalene, an oil found on skin cells, has six double carbon bonds in its molecules which interact with, and break apart, ozone. Chemist Charles Weschler and his team analyzed dust from non-floor surfaces in Demark, showing that squalene was more effective than cholesterol, which is another oil found on skin, at removing ozone.

Squalene human skin dust isn’t the only anti-ozone agent found in a household either – other chemicals that contain double bonds between atoms, like oleic acid found in certain cooking oils, and some surfaces, like those made of rubber or neoprene, also consume ozone, according to Weschler. Squalene found in living human skin also shows a contribution to reducing ozone levels, although in a smaller percentage.

“Basically, human beings are large ozone sinks. We have only found this out within the last five years!” Weschler wrote in an email to LiveScience. “In an occupied room humans consume more ozone than dust [does]. However, dust continues to react with ozone even when the room is not occupied.”

The average human sheds around 500 million skin cells per day, which means that your squalene levels will get replenished everyday, and although dust can be considered in this case beneficial, it will build up and at some point dusting is required. Dust can irritate allergies or even pass along microbes, so one should be always careful.

“The skin flakes shed by one person may trigger an allergic response in another person or may serve to pass along microbes that could cause an adverse effect,” Weschler wrote. “While it is a good thing that dust consumes ozone, we should continue to clean — to remove dust. Human occupants will continue to ‘recharge’ squalene in dust and on the surfaces that they contact.”

Story courtesy of Popsci.

Huge dust storm chokes Sydney

 

A significant part of Australia’s east coast, including country’s biggest city, Sydney, has been engulfed by a shroud of red dust blown mostly from the desert outback. Visibility was so bad that most if not all flights were delayed, and of course, there were the usual folks who started screaming that this is the apocalypse. Turns out, it wasn’t.

Photo by Merbabu.

Numerous buildings, including the famous Opera House were covered in a thick blanket of dust and people took cover in their houses or nearby buildings. Lots of folks took to wearing masks and the emergency service reported a huge number of people who came in with respiratory problems. The transportation system was crippled also and doctors warned especially children and elder people to stay indoor until the storm passed, and even a few hours after that.

On Wednesday morning, powerful winds generated by a major cold air front transported tons and tons of dust from the drought plagued outback and brought it into the city. Dust storms are not really that uncommon, but they rarely take place somewhere else than the desert (or nearby areas); also, the pollution levels from the air were the highest recorded ever, with the 15,500 micrograms of particles per cubic meter generating a Mars-like landscape.

“On a clear day the readings for particulate matter or PM10 is around 10-20 micrograms per cubic meter,” said Chris Eiser of the NSW department of the environment. “During a bushfire, when there is heavy smoke around, we might see readings of around 300 to 500 micrograms per cubic meter.”

 

Locals described waking up to the storm as waking up on Mars, or even yet, in the middle of the apocalypse. The sky was soaked in red, the wind was blowing strongly and the whole scenery was somewhere between eerie and downright scary. They weren’t really as dangerous as they seemed, but they could do a significant amount of damage to one’s health.

“Dust storms are particularly hazardous for anyone with chronic lung disease or sinus disease. Once the particles per cubic metre are above 300, dust storms pose a risk to lung health,” said Dr Phillip Thompson of the University of Western Australia.

Here’s a video and some pics.

Dust storm Sydney 23 September 2009

sydney-dust-storm

the-bradfield-freeway-004

Pics via The Guardian

Subway Dust and your lungs

 

subway

Subway trains produce airborne dust particles that could damage the lungs, a new study concludes.

In the world today it is harder and harder to drive around town or to another town – itt is not cheap, and it takes time. So the subway is a good choice to more and more people. But as with anything, the downsides it brings to the table are more and more visible.

Sophie Lanone and colleagues point out that previous studies of the London and Stockholm subway systems also have identified particulate matter which raises health concerns. They collected the dust and then exposed live mice and cultured mice cells to the dust over a 24-hour period. This caused transient lung inflammation and increased levels of several substances produced by the immune system that might cause tissue damage.

“To the best of our knowledge, this is the first evaluation of the biological effects of particulate matter from the Paris subway system as well as the first comprehensive study to evaluate the in vivo effect of subway particulate matter,” the report states.

So it is known that the dust produced by subway trains could harm your lungs in numerous ways. It has large amounts of iron particles and very low levels of endotoxin, a potentially toxic compound produced by bacteria. The subway is a fast but unhealthy way of traveling.