Methane Keeps Showing Up on Mars. NASA Just Got Closer to Solving The Mystery - ScienceAlert

Methane is an organic molecule that hangs around in Earth's atmosphere and is mostly produced by living organisms, most notoriously by farting cows. Its detection on Mars, on the other hand, has been a weird mystery for planetary scientists. 

In recent years, NASA's Curiosity rover has picked up tiny traces of methane numerous times on the red planet. While these emissions might be coming from some geological process, it was possible they could indicate the presence of some sort of life form on Mars (unlikely to be cows, of course). 

As you'd expect, scientists are really excited by that prospect, but the data are confusing. Higher in the atmosphere, orbiting technology from the European Space Agency (ESA) has detected no methane in any concentration. 

That's strange, because even though plumes of methane would dilute into the Martian atmosphere, like a pinch of salt in an Olympic-sized swimming pool, our instruments are sensitive enough to still detect that briny hint.

"[W]hen the European team announced that it saw no methane, I was definitely shocked," says planetary scientist Chris Webster from NASA's Jet Propulsion Laboratory. 

So why the discrepancy? Webster and his colleagues went back to look at the data again, ruling out every little factor that might be contributing to the rover's detection of methane.

"So we looked at correlations with the pointing of the rover, the ground, the crushing of rocks, the wheel degradation - you name it," Webster explains. 

"I cannot overstate the effort the team has put into looking at every little detail to make sure those measurements are correct, and they are."

As it turns out, the plumes of methane measured by Curiosity were not flukes. Instead, the discrepancy in measurements boils down to the Sun. The team found methane on the Martian surface can ebb and flow with the time of day, and the power-intensive instrument on Curiosity that detects methane mostly operates at night.

This is when the Martian atmosphere is more still, which means methane doesn't rise and dilute into the atmosphere like it does in the heat of the day. As a result, researchers think the gas sticks around near the surface of the planet at night, and during the day, the methane is diluted such that ESA's orbiting instrument (which needs sunlight to work) can't detect it at a distance.

To confirm their prediction, the research team collected high-precision measurements of Martian methane over the course of two days, the first time Curiosity has done so in daylight. They also took measurements during the intervening night.

As expected, the seeping methane sat near the surface of the planet at night and dissolved into the atmosphere in the day.

"John [E. Moores, another member of Curiosity's science team] predicted that methane should effectively go down to zero during the day, and our two daytime measurements confirmed that," explains planetary scientist Paul Mahaffy from NASA's Goddard Space Flight Center.

"So that's one way of putting to bed this big discrepancy."

It's still unclear, however, why methane doesn't appear to be building up in the Martian atmosphere over time - according to the researchers, it should last for at least 300 years before degrading in the radiation streaming from the Sun.

Since it's unlikely for the Gale crater to be the only source of this planetary micro-seepage of methane (because Gale crater just isn't that special from a geological perspective), they think something must be destroying or sequestering all that methane before it can gather in the atmosphere. 

The team is now testing whether dust or an abundance of oxygen could play a role in that.

Part of the mystery might be solved, but now we have more questions. Curiosity is living up to its name.

The study was published in Astronomy & Astrophysics.

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2021-07-01 01:52:18Z
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SpaceX delivers 88 satellites to orbit, lands first stage onshore for first time in 2021 - Yahoo Canada Finance

SpaceX launched 85 satellites for external customers, as well as three Starlink satellites, to orbit on Tuesday, marking the second successful launch of the company's dedicated rideshare missions. While the Transporter-2 mission will deliver fewer objects to space than the first rideshare mission (the Transporter-1 sent up 143 satellites, a new record), it launched more mass to orbit overall.

The Transporter launches are part of the company’s rideshare business model. Announced in 2019, these missions split up the rocket’s payload capacity among multiple customers, resulting in lower costs for each – many of whom are smaller companies that may find the expenses associated with getting to orbit otherwise impossible to pay. SpaceX still ends up with a full launch and the revenue to operate it.

The Falcon 9 rocket took off from Cape Canaveral in Florida at around 3:31 PM Eastern time. It’s the 20th Falcon 9 launch in 2021 and the first launch this year that featured the first stage returning to land onshore, rather than on a drone ship at sea. The first stage booster separated at around 3:34 PM ET and returned to Cape Canaveral and successfully landed around eight minutes after liftoff. This was its eighth flight.

Image Credits: SpaceX (opens in a new window)

The mission includes nearly 10 customers, some of whom are launch service providers who are themselves organizing customer payloads – like Spaceflight Inc., which is launching 36 small satellites on behalf of 14 customers, as well as its electric propulsion vehicle dubbed Sherpa-LTE. It also includes the first satellite launch for space intelligence company Umbra and Loft Orbital’s “rideshare” satellites, YAM-2 and YAM-3, each of which are equipped with five independent sensors for separate customers.

As this was SpaceX’s 20th launch this year (and 127th mission to date), it’s pretty safe to assume that the company will far surpass last year’s record of 26 launches.

This was the second attempt of the Transporter-2 launch, which was originally scheduled for June 29. That launch was halted at T-11 seconds after a rotary aircraft entered the flight zone. SpaceX CEO Elon Musk called the regulatory system broken in response.

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2021-06-30 19:42:07Z
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'Extreme' white dwarf sets cosmic records for small size, huge mass - Toronto Sun

Author of the article:

Reuters

Will Dunham

A newfound small white dwarf, called ZTF J1901+1458 and located 130 light-years from Earth, that is slightly larger than the size of the moon in diameter but 1.35 times the mass of our sun, making it both the smallest in size and largest in mass of any known white dwarf is seen in an undated illustration. Photo by Giuseppe Parisi /Handout via REUTERS

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WASHINGTON — In their death throes, roughly 97% of all stars become a smoldering stellar zombie called a white dwarf, one of the densest objects in the cosmos. A newly discovered white dwarf is being hailed as the most “extreme” one of these on record, cramming a frightful amount of mass into a surprisingly small package.

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Scientists said on Wednesday this highly magnetized and rapidly rotating white dwarf is 35% more massive than our sun yet boasts a petite diameter only a bit larger than Earth’s moon. That means it has the greatest mass and, counterintuitively, littlest size of any known white dwarf, owing to its tremendous density.

Only two other types of objects – black holes and neutron stars – are more compact than white dwarfs.

The way this white dwarf, named ZTF J1901+1458, was born also is unusual. It apparently is the product of a binary star system in which two stars orbit each other. These two stars separately evolved into white dwarfs at the end of their life cycles, then spiraled toward one another and merged into a single entity.

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With even a smidgen more combined mass, this merger would have resulted in an immense stellar explosion called a supernova, said Caltech astrophysicist Ilaria Caiazzo, lead author of the study published in the journal Nature. It still might explode at some point in the future, Caiazzo added.

“This white dwarf is really extreme,” Caiazzo said. “We found an object that is really at the limit of how small and heavy a white dwarf could be.”

It is located relatively nearby in our Milky Way galaxy, about 130 light years from Earth. A light year is the distance light travels in a year – about 5.9 trillion miles (9.5 trillion km).

The white dwarf is actually shrinking very gradually, becoming ever more dense. If it does not explode, that could lead to a core collapse transforming it into a neutron star, another type of stellar remnant about the size of a city, typically formed after certain very massive stars go supernova. This would be a previously unrecognized path to neutron star formation.

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The white dwarf was spotted by astrophysicist and study co-author Kevin Burdge from Caltech’s Palomar Observatory.

“White dwarfs are the most common form of stellar remnant,” said Burdge, who worked on the study at Caltech and is headed to MIT. “So it’s stunning to see the most extreme outliers among them.”

We apologize, but this video has failed to load.

Its diameter of roughly 2,670 miles (4,300 km) – approximately the distance from Boston to Los Angeles or London to Tehran – slightly exceeds the moon’s diameter of about 2,160 miles (3,475 km).

While our sun rotates around its axis once every 27 days, this white dwarf does so every seven minutes. Its magnetic field is about a billion times stronger than Earth’s.

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Stars with up to eight times the mass of our sun are thought to be destined to end up as a white dwarf. Such stars eventually burn up all of the hydrogen they use as fuel through nuclear fusion. At this point, gravity causes them to collapse and blow off their outer layers in a ‘red giant’ stage, eventually leaving a dense core that is a white dwarf.

White dwarfs initially have high temperatures but gradually cool over time, lacking any new energy source. In roughly 5 billion years, our sun is expected to become a red giant and later a white dwarf.

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2021-06-30 16:49:40Z
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Scientists intensify electrolysis, utilize carbon dioxide more efficiently with magnets - Science Daily

For decades, researchers have been working toward mitigating excess atmospheric carbon dioxide (CO₂) emissions. One promising approach captures atmospheric CO₂ and then, through CO₂ electrolysis, converts it into value-added chemicals and intermediates -- like ethanol, ethylene, and other useful chemicals. While significant research has been devoted to improving the rate and selectivity of CO₂ electrolysis, reducing the energy consumption of this high-power process has been underexplored.

In ACS Energy Letters, researchers from the University of Illinois Urbana-Champaign report a new opportunity to use magnetism to reduce the energy required for CO₂ electrolysis by up to 60% in a flow electrolyzer.

In a typical CO₂ flow electrolyzer, electricity is supplied to drive the reactions at the cathode (where carbon dioxide is reduced into useful byproducts) and the anode (where water is oxidized, producing oxygen).

Most studies have focused on making the reduction reaction at the cathode more efficient at higher rates; however, this process requires little energy compared to the oxidation reaction on the anode -- which often accounts for more than 80% of the energy required for CO₂ electrolysis, and therefore, offers the most room for improvement.

"The answer was staring us right in the face -- of course, the trick is to reduce the energy consumption at the anode," said first-author Saket S. Bhargava, a graduate student in chemical and biomolecular engineering at Illinois. "We decided that if oxygen evolution is the problem, why not use a magnetic field at the oxygen evolving electrode and see what happens to the entire system."

They used a magnetic field at the anode to achieve energy savings ranging from 7% to 64% by enhancing mass transport to/from the electrode. They also swapped the traditional iridium catalyst -- a precious metal -- with a nickel-iron catalyst comprised of abundant elements.

"Our ultimate goal is to transform carbon dioxide back into carbon-based chemicals," said lead author Paul Kenis, a chemical and biomolecular engineering professor and department head at Illinois. "With this study, we have demonstrated how further to reduce the significant energy requirements for CO₂ electrolysis, hopefully making this process more viable for adoption by industry."

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Materials provided by University of Illinois College of Liberal Arts & Sciences. Original written by Claire Benjamin. Note: Content may be edited for style and length.

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2021-06-30 18:53:29Z
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Astronomers spot a white dwarf, as small as the moon, on verge of collapse - CNET

This illustration places the newly found white dwarf star right next to our moon for size comparison.

Giuseppe Parisi

What's slightly larger than our moon but almost 1.4 times more massive than our sun? ZTF J1901+1458, one of the smallest white dwarf stars ever spotted by astronomers. The dying husk of a sun-like star was spotted relatively close by, just 133 light-years away, by a series of ground- and space-based telescopes.

In a study published in the journal Nature on Wednesday, researchers detail the discovery and characteristics of ZTF J1901+1458, which is so named because it was spotted by the Zwicky Transient Facility, a sky survey using the Palomar Observatory in California that searches space for any objects with sudden changes in brightness. It's quite an extreme star.

White dwarfs are formed when stars about eight times the mass of our sun or smaller come to the end of their lives. As they run out of fuel, they begin to collapse -- but somewhat paradoxically, this initial collapse causes the star to swell to monstrous sizes and become a red giant (like the famous star Betelgeuse ). 

This process also sees the star cool down a little and its core contract, which releases a huge amount of energy, again making it bigger. However, it starts to lose its outer layers and leave behind just an extremely dense core. A white dwarf.

That's what the research team saw in the ZTF data: the husk of a blown-out star. To get a better handle on its characteristics, they used data collected by the European Space Agency's Gaia satellite, the Keck telescope in Hawaii and NASA's Swift observatory. Once they'd analyzed J1901+1458, they realized it something special: It was rotating extremely quickly and appeared to be almost as massive as a white dwarf can get. 

The team believe the white dwarf was originally two stars that danced with each other for billions of years. They both evolved to become white dwarfs, before finally merging and creating the new, much more massive star.

"We caught this very interesting object that wasn't quite massive enough to explode," said Ilaria Caiazzo, an astrophysicist at Caltech and lead author of the new study, in a press release. "We are truly probing how massive a white dwarf can be."

It has also been described as the smallest white dwarf discovered, but that title might go to another object believed to be a white dwarf, known as RX J0648.0–4418.

So what will happen to the white dwarf now?

"This is highly speculative, but it's possible that the white dwarf is massive enough to further collapse into a neutron star," said Caiazzo. Usually neutron stars form when huge stars collapse, but it's speculated that about one in 10 might be formed from the collapse of a white dwarf.

That's because weird things are happening in the super-dense core of a white dwarf. Caiazzo describes a process at the subatomic scale, where electrons are being captured and forming neutrons. As more and more electrons are removed, the core gets closer to collapse and ultimately ends up as a "zombie" neutron star, one of the most unusual and mysterious cosmic bodies in the universe. 

"There are so many questions to address," notes Caiazzo.  

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2021-06-30 15:15:07Z
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Celestial "Pac-Man": Astronomers spot massive black holes gobbling up city-sized neutron stars for the first time - CBS News

In what looks like a celestial version of "Pac-Man," scientists have detected black holes gobbling up neutron stars — marking the observation of collisions between the two most extreme objects in the universe for the very first time.

And the hefty feasts occurred one billion years ago.

Artist's impression of a neutron star and black hole merging.  Carl Knox/OzGrav/Swinburne University

Within a 10-day time frame, a team of over 1,000 international scientists spotted the rare cosmic event twice using the Laser Interferometer Gravitational-Wave Observatory in the U.S. and the Virgo gravitational-wave observatory in Italy, They published their findings, originally documented in January 2020, on Tuesday in The Astrophysical Journal Letters. 

While researchers have suspected this type of event in the past, this is the first time one has been confirmed. Ecstatic researchers say the observations of the death spiral and merger of neutron stars and black holes will help "unlock some of the most complex mysteries of the universe," including the building blocks of matter and the nature of the space-time continuum.

Co-author Susan Scott said that, although the collisions occurred about a billion years ago, they were so massive that their gravitational waves — ripples in space-time that shake the entire universe — have only just finished traveling at least 900 million light years to reach Earth. 

"These collisions have shaken the universe to its core and we've detected the ripples they have sent hurtling through the cosmos," she said in a statement Wednesday. "Each collision isn't just the coming together of two massive and dense objects. It's really like Pac-Man, with a black hole swallowing its companion neutron star whole."  

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Ahead of the collision and merger, the two massive objects, both the corpses of massive dead stars, orbit each other at around half the speed of light. During the newly-captured collision, the neutron star is warped and deformed as it nears the black hole, which becomes more massive as it swallows the star whole. 

In one instance, a black hole with a mass nine times that of our sun swallowed up a neutron star with a mass around twice that of the sun. The other event involved a black hole with a mass about six times bigger than the sun snacking on a neutron star about 1.5 times the sun's mass. 

All of the mass of a neutron star is squeezed into an extremely dense star, which is about the size of a city. Scientists say that one teaspoon of a neutron star weighs as much as all of humanity.

Image from a MAYA collaboration numerical relativity simulation of a neutron star-black hole (NSBH) binary merger, showing the disruption of the neutron star.  Deborah Ferguson (UT Ausitn), Bhavesh Khamesra (Georgia Tech), and Karan Jani (Vanderbilt University).

Astronomers searched the sky for flashes of light that may have resulted from the events, but none were found, possibly due to their distance from Earth. Additionally, the black holes in these cases were large enough to swallow the entirety of the neutron stars, leaving behind no light to detect. 

"These were not events where the black holes munched on the neutron stars like the cookie monster and flung bits and pieces about," said co-author Patrick Brady. "That 'flinging about' is what would produce light, and we don't think that happened in these cases."

Massive black hole discovered in Milky Way 01:09

Scientists have previously captured two black holes smashing together and the collision of two neutron stars — but they "have waiting a very long time" to witness the two come together. 

"Now, we've completed the last piece of the puzzle with the first confirmed observations of gravitational waves from a black hole and a neutron star colliding," Scott said.

Astronomers have spent decades hunting for this sort of event in the Milky Way galaxy, but have yet to find any. 

"With this new discovery of neutron star-black hole mergers outside our galaxy, we have found the missing type of binary," co-author Astrid Lamberts said. "We can finally begin to understand how many of these systems exist, how often they merge, and why we have not yet seen examples in the Milky Way." 

"These kind of detections are incredibly rare," said co-author Johannes Eichholz. "We haven't detected these events once — but twice and within 10 days of each other. "Like the ripples from these two events, which have been felt a billion years later, these findings will have a profound impact on our understanding of the universe for many years to come."

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2021-06-30 12:13:35Z
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Mouse thought extinct for 150 years found living on island - CTV News

AMY WOODYATT -- A mouse thought to have become extinct more than 150 years ago has been found alive on an island off the coast of Western Australia, researchers have discovered.

Scientists compared DNA samples from eight extinct Australian rodents and 42 of their living relatives, and discovered that the extinct Gould's mouse was "indistinguishable" from the Shark Bay mouse.

Researchers were studying the decline of the country's native species since the arrival of Europeans in Australia in 1788.

The mouse -- which will still be known by the common name "djoongari," or "Shark Bay mouse" -- was once found across the country, from south-west Western Australia to New South Wales, but was last seen in 1857. The introduction of invasive species, agricultural land clearing and new diseases destroyed the native species, researchers said, adding that climate change and poor fire management also affected population sizes.

The remaining populations of the djoongari were located on a single 42 square-kilometre island in Shark Bay, Bernier Island. One small population is not enough for a species to survive, researchers said, so the mice have been taken to two other islands to establish new populations.

"The resurrection of this species brings good news in the face of the disproportionally high rate of native rodent extinction, making up 41 per cent of Australian mammal extinction since European colonisation in 1788," lead author Emily Roycroft, an evolutionary biologist from the Australian National University (ANU), said in a statement.

"It is exciting that Gould's mouse is still around, but its disappearance from the mainland highlights how quickly this species went from being distributed across most of Australia, to only surviving on offshore islands in Western Australia. It's a huge population collapse," she added.

The team also studied seven other extinct native species, which were found to have high genetic diversity immediately before extinction, showing that their populations were widespread before Europeans arrived.

"This shows genetic diversity does not provide guaranteed insurance against extinction," Roycroft warned.

More than 80% of Australia's mammals are endemic, as result of Australia's long period of isolation from other continents. But the country has what researchers described in a 2015 paper as an "extraordinary rate of extinction." Meanwhile, a study published in 2019 found that Australia was home to 6-10% of the world's post-1500 recognized extinctions.

Roycroft said the extinction of the seven native species happened "very quickly."

"They were likely common, with large populations prior to the arrival of Europeans. But the introduction of feral cats, foxes, and other invasive species, agricultural land clearing and new diseases have absolutely decimated native species," she said.

Humans have already wiped out hundreds of species and pushed many more to the brink of extinction through wildlife trade, pollution, habitat loss and the use of toxic substances. The Earth's sixth mass extinction is happening now, much faster than previously expected -- and the rate at which species are dying out has accelerated in recent decades, scientists have warned.

The research will be published in the journal PNAS next month.

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2021-06-30 13:57:24Z
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Scientists say there's no life on Venus — but Jupiter has potential – Barrie 360 - Barrie 360

Sophie Lewis – CBS News

It turns out the clouds of Venus aren’t made of the right stuff to support life — so now, scientists are turning to Jupiter instead.

Hellish temperatures on the surface of Venus can reach nearly 900 degrees Fahrenheit; 482 degrees Celsius — creating a less-than-hospitable planet. But a study last year renewed hopes that Venus could support life after researchers detected phosphine gas, which is produced by bacteria on Earth, in its more temperate clouds. 

Now, a new study published Monday in the journal Nature Astronomy, found that the water concentration in our nearest neighbor’s infamous sulphuric acid clouds is just too dry for life as we know it to find a way to survive. 

Microbiologist John Hallsworth discovered a terrestrial fungus in 2017 that is capable of surviving at 58.5% relative humidity — the driest conditions a living creature has ever withstood. He decided to test whether they could exist on other planets. 

“We bent over backwards to argue that the most extreme, tolerant microbes on Earth could potentially have activity on Venus,” Hallsworth said at a press conference.

Hallsworth found no known living organism could survive our sister planet’s atmosphere, which is equivalent to a relative humidity of 0.4%. His team studied the planet’s “water activity,” meaning its concentration of water molecules, rather than the actual quantity of water, to come to their conclusion. 

Water activity is calculated based on direct observations of pressure, temperature and water concentration. Researchers used existing measurements from seven U.S. and Soviet probes and one orbiter mission from the late 1970s and early 1980s.

“It’s more than 100 times too low,” he said. “It’s almost at the bottom of the scale, at an unbridgeable distance from what life requires to be active.”

“The search for extraterrestrial life has sometimes been a bit simplistic in its attitude to water,” said co-author Philip Ball. “As our work shows, it’s not enough to say that liquid water equates with habitability. We’ve got to think too about how Earth-like organisms actually use it – which shows us that we then have to ask how much of the water is actually available for those biological uses.” 

The findings come nearly a month after NASA announced two new discovery missions to the inferno-like planet, scheduled to launch between 2028 and 2030. One of those missions could help determine if Venus could have supported life billions of years ago. 

“One of the missions will fly through the atmosphere and measure trace gases… which will tell us a lot about Venus’s evolutionary history and will start to address questions like how much atmosphere did Venus have, where did it go, what happened?” McKay said. 

Could Jupiter support life? 

Scientists may have ruled out alien life on Venus, but Jupiter still holds promise. 

Studying probes that visited other planets, researchers found that Jupiter’s clouds have a high enough concentration of water, and a viable temperature, for life to exist — assuming other requirements, like nutrients, are also present.  

“The results were much more optimistic,” said co-author Chris McKay. “There is at least a layer in the clouds of Jupiter where the water requirements are met.”

Illustration of stormy clouds on Jupiter, based on images from the Stellar Reference Unit camera of NASA’s Juno mission. NASA/JPL-CALTECH/SWRI/MSSS/GERALD EICHSTÄDT/HEIDI N. BECKER/KOJI KURAMURA

But it’s a lot easier to rule out alien life on Venus than to prove it’s possible on Jupiter.

“To show that that layer is habitable we would have to go through all the requirements for life and show that they’re all met,” McKay said. 

He added that further exploration is needed to determine other factors, like ultraviolet exposure and energy sources. But the research does provide a promising basis to study all other planets in the future.  

“We have also performed calculations for Mars and Earth and show that these calculations can be done for planets outside our solar system,” Hallsworth said. “While our research doesn’t claim that alien (microbial-type) life does exist on other planets in our solar system, it shows that if the water activity and other conditions are right, then such life could exist in places where we haven’t previously been looking.” 

banner image: Venus via NASA/JPL-CALTECH

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2021-06-30 11:58:59Z
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Mysterious methane detections on Mars baffle NASA scientists - Sky News

Detections of methane on Mars have excited scientists because, on Earth, the gas is often produced by microbes - its presence could indicate that similar life was, or is, present on the red planet.

There are potential geological processes that could produce methane too, but even before identifying the source of the gas on Mars, scientists have been trying to solve another mystery.

The detections of methane aren't consistent. Some instruments, such as NASA's Curiosity rover, have repeatedly detected the gas above the surface of the Gale Crater. Others, such as ESA's (European Space Agency) orbiter, haven't found any traces of methane higher up in the Martian atmosphere.

Aboard the Curiosity rover is an instrument called the Tunable Laser Spectrometer (TLS) which has detected varying amounts of methane - from less than one-half part per billion "equivalent to about a pinch of salt diluted in an Olympic-size swimming pool" to up to 20 parts per billion.

The issue can't be one of design or malfunction. ESA's ExoMars Trace Gas Orbiter is "designed to be the gold standard for measuring methane and other gases over the whole planet", explained NASA, and yet it was finding no methane at all.

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The TLS instrument is so preside, it has even been licensed for use in industrial systems and fighter aircraft to monitor for gas levels.

"When the Trace Gas Orbiter came on board in 2016, I was fully expecting the orbiter team to report that there’s a small amount of methane everywhere on Mars," said Chris Webster, who leads the TLS instrument for NASA.

More on Nasa

"When the European team announced that it saw no methane, I was definitely shocked," he added.

The TLS team checked to see if the rover was releasing the gas itself somehow.

"We looked at correlations with the pointing of the rover, the ground, the crushing of rocks, the wheel degradation -you name it. I cannot overstate the effort the team has put into looking at every little detail to make sure those measurements are correct, and they are."

Image: The gas was detected by NASA's Curiosity rover. Pic: NASA

At this point, John Moores, a scientist from York University in Toronto proposed a counter-intuitive solution.

"I took what some of my colleagues are calling a very Canadian view of this, in the sense that I asked the question: 'What if Curiosity and the Trace Gas Orbiter are both right?'" Moores said.

Working with the Curiosity team, Moores hypothesised that the discrepancy between the measurements came down to the time of day they were taken.

Image: The methane blast was detected near to the planet's Gale Crater. Pic: NASA

The TLS, they realised, operates mostly at night when Curiosity's other instruments are sleeping. As the Martian atmosphere is calm at night, any methane seeping up from the ground builds up near the surface.

The orbiter however depends on sunlight to pinpoint trace gases about 5km from the planet's surface. As the atmosphere is more active during the day, any methane present would have been diluted to undetectable levels.

Experiments quickly confirmed that this was the case, but another mystery remained even beyond the origin of the methane: Why was it disappearing?

Image: It remains unknown what is producing the methane on Mars

Methane is a stable molecule. Even without a protective atmosphere, it is expected to last for 300 years on Mars before solar radiation tears it apart.

If it is constantly seeping from all craters on the planet - something which researchers believe, as there is apparently nothing geologically unique about the Gale Crater - then there should be enough in the atmosphere for the orbiter to detect.

The researchers are now experimenting to see whether "very low-level electric discharges induced by dust in the Martian atmosphere could destroy methane, or whether abundant oxygen at the Martian surface quickly destroys methane before it can reach the upper atmosphere".

"We need to determine whether there’s a faster destruction mechanism than normal to fully reconcile the data sets from the rover and the orbiter," Webster said.

After that, the team can try and figure out where the methane is coming from.

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2021-06-30 10:49:14Z
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Is there methane on Mars? Scientists close to solving mystery of the gas on Red Planet - India Today

When it comes to the search of ancient microbial life beyond Earth, Mars has been the closest to having traces of gases and conditions that might support the activity. However, one such gas has puzzled scientists for years. The question of whether methane, the main constituent of natural gas on Earth, is present on Mars has baffled scientists.

While the gas has been observed by the Curiosity rover, which is trundling on the surface of the Gale crater on Mars, the European Space Agency's orbiter hovering above has not been able to detect it in the Martian atmosphere.

Now, a new study suggests that methane concentrations rise and fall throughout the day at the surface of Gale crater, which could in turn be causing the discrepancy in detecting the gas.

The study published in the Astronomy & Astrophysics journal states that the quantity, distribution, and behaviour of methane in the atmosphere of Mars are of great interest since the gas is recognised as a potential biosignature for microbes to flourish.

The Gale Crater as seen by Curiosity rover. (Photo: JPL)

WHY HAS METHANE BAFFLED SCIENTISTS?

On Earth, a significant amount of methane is produced by microbes that help most livestock digest plants. Therefore, its potential presence on a planet 300 million kilometres away has created excitement. The presence of methane on Mars could imply that microbes were, or are, living on the Red Planet. However, there are chances that methane on Mars could have nothing to do with microbes or any other biology and could have been produced by geological processes that involve the interaction of rocks, water, and heat.

While its presence is exciting, its detection by one instrument while no trace on the other has been a cause of concern.

The Tunable Laser Spectrometer (TLS) instrument onboard Curiosity had measured less than one-half part per billion in volume of methane on average in Gale crater. "That’s equivalent to about a pinch of salt diluted in an Olympic-size swimming pool," Nasa said in a statement.

The Gale Crater as seen from above with Curiosity trundling around. (Photo: Nasa)

However, the ExoMars Trace Gas Orbiter hasn’t detected any methane higher in the Martian atmosphere.

Some scientists had suggested that the rover might itself be releasing the gas as it moved ahead crushing rocks and due to the degradation of its wheels. However, a deep analysis of the machine showed no such chemical reaction happening as Curiosity moved about.

DIFFERENCES IN METHANE CONCENTRATION DURING DAY AND NIGHT

Now scientists have studied the discrepancy between methane measurements by analysing the time at which the readings are taken. The rover's TLS operates mostly at night when no other Curiosity instruments are working. The Martian atmosphere is calm at night and so methane seeping from the ground builds up near the surface where Curiosity can detect it, scientists observed.

However, the orbiter requires sunlight to pinpoint methane about 5 kilometres above the surface.

Some scientists had suggested that the rover might itself be releasing the gas. (Photo: Nasa)

The heat from the Sun churns the atmosphere as warm air rises and cool air sinks. Therefore, the methane that is confined near the surface at night is mixed into the broader atmosphere during the day, which dilutes it to undetectable levels. This leads to no reading on the orbiter.

Scientists are now looking at solving why methane is not present in the Martian atmosphere which is 95 per cent carbon dioxide. "Experiments are underway to test whether very low-level electric discharges induced by dust in the Martian atmosphere could destroy methane, or whether abundant oxygen at the Martian surface quickly destroys methane before it can reach the upper atmosphere," Nasa said in a statement.

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2021-06-30 10:46:41Z
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SpaceX launch was called off due to another aircraft - Business Insider

Tesla and SpaceX CEO Elon Musk.

Win McNamee/Getty Images

• Elon Musk tweeted an aircraft crossed the "keep out zone," preventing a SpaceX rocket launch.
• The SpaceX CEO said that the zone is "unreasonably gigantic."
• Musk said the rules reflect a "broken" spacefaring regulatory system.
• See more stories on Insider's business page.

Tesla CEO Elon Musk said a SpaceX launch was called off because an aircraft entered the so-called keep out zone.

Musk, who also is CEO of SpaceX, tweeted Tuesday that the "keep out zone" is "unreasonably gigantic," and since an aircraft entered it, the company was not able to launch its own. 

SkyVector

He alluded to the fact that those rules reflect a need to update existing regulations around space travel.

"There is simply no way that humanity can become a spacefaring civilization without major regulatory reform," Musk tweeted. "The current regulatory system is broken."

—Elon Musk (@elonmusk) June 29, 2021

A Federal Aviation Administration spokesperson later told ClickOrlando.com, the website for Orlando's CBS television affiliate, that the aircraft was a private helicopter that entered the restricted area in the final 11 seconds before launch. The FAA is investigating the incident, the spokesperson said.

SpaceX launches have been canceled in the past under circumstances such as inclement weather. But this could be the first instance in which a launch has been called off due to another aircraft occupying the "keep out zone." 

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2021-06-29 22:51:06Z
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NASA Curiosity rover may have solved Mars methane mystery - CNET

NASA's Curiosity rover snapped this selfie in 2020.

NASA/JPL-Caltech/MSSS

Methane. On Earth, it's the stuff of cow farts and burps. On Mars, it's the stuff of mysteries. Scientists have been puzzling over methane readings from Mars, and NASA may be a step closer to figuring out what's going on with the gas on the red planet. It turns out the time of day has a big impact on methane detections.

Methane is particularly intriguing because it can be a byproduct of living things, including microbes. Researchers are trying to work out if Mars once hosted microbial life, or if microbes might possibly survive there now. But don't get too hyped; methane can also have a geologic origin.

What's weird about methane on the red planet is that NASA's Curiosity rover has detected the gas near the surface in the Gale Crater, but the European Space Agency's ExoMars Trace Gas Orbiter spacecraft isn't seeing methane higher up in the atmosphere. So what's going on?

Curiosity's Tunable Laser Spectrometer instrument is part of its Sample Analysis at Mars system, essentially a portable chemistry lab. Usually, TLS detects a small amount of methane NASA describes as "equivalent to about a pinch of salt diluted in an Olympic-size swimming pool." In 2019, TLS notably detected a considerable spike in methane levels.

The ExoMars orbiter, which arrived at Mars in 2016, hasn't been seeing what Curiosity sees. "But when the European team announced that it saw no methane, I was definitely shocked," TLS instrument lead Chris Webster said in a NASA statement on Tuesday.

Mars pits: Gaze into the abyss with these wild NASA images

See all photos

The discrepancy may come down to the times of day when the orbiter and rover work. The power-hungry TLS on the rover operates at night so it doesn't conflict with other instruments. The orbiter makes its detections during the day when it has sunlight to help it. What may be happening is that methane pools near the surface during calm nights and dissipates during the day, making it invisible to the spacecraft.

The Curiosity team tested this idea by taking daytime methane measurements, and indeed the gas disappeared during the day. The researchers published their findings today in the Astronomy and Astrophysics journal (PDF link).

While one methane mystery may have an explanation, another gassy conundrum lingers. NASA is still trying to sort out the "global methane puzzle at Mars." Methane released from Mars craters should remain stable enough -- and accumulate in the atmosphere enough -- for detection by the Trace Gas Orbiter. 

Scientists are now looking into what might be destroying the methane. "We need to determine whether there's a faster destruction mechanism than normal to fully reconcile the data sets from the rover and the orbiter," said Webster. Until then, Mars methane will remain an enigma.

Follow CNET's 2021 Space Calendar to stay up to date with all the latest space news this year. You can even add it to your own Google Calendar.   

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2021-06-30 00:57:01Z
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Astronomers detect black holes swallowing up neutron stars for the first time - CNET

On Jan. 5, 2020, astrophysicists heard a chirp from a distant part of the cosmos, some 900 million light-years away. The fleeting sound was unlike any they'd heard before and was caused by a great ripple in space-time -- a gravitational wave -- that spread out across the universe from over 900 million light-years away, washing over the Earth and pinging detectors. Chirp. 

Then, 10 days later, they heard another, similar sound. A cosmic twin. Gravitational waves had once again pinged Earth's detectors. Chirp.

After careful analysis, the two signals have been identified as emanating from extreme, never-before-seen events in deep space: the collision between a black hole and a neutron star. 

The pair of collisions (or, less poetically, "mergers") are detailed in a new study published in the Astrophysical Journal Letters on Tuesday, featuring over 1,000 scientists from the LIGO/Virgo and KAGRA collaborations, a multinational effort to hunt for gravitational waves. The two newly described events are named GW200105 and GW200115, for the dates they were discovered, and provide the first definitive evidence of an elusive merger.

Prior to the dual detection, astronomers had only found black holes merging with black holes and neutron stars merging with neutron stars.

"We've been waiting and expecting, at some stage, to detect a system with one of each," said Susan Scott, an astrophysicist at Australian National University and a member of OzGrav and the LIGO collaboration. 

Now they have.

Over the last two years, there had been suggestions that a collision between a neutron star and a black hole may have been spotted -- but one of the objects appeared a little unusual. It was too big to be a neutron star and too small to be a black hole. The unknown object remains a mystery, which means GW200105 and GW200115 will go down in history.

"These are the first really confident detections of the merger of a neutron star with a black hole," adds Rory Smith, an astrophysicist at Monash University in Australia and a member of the LIGO collaboration.

Chirpy

A quick interlude before we continue. 

Black holes and neutron stars are strange objects. They are the relics of dead stars and form at the end of a star's life. The size of a star affects how its life comes to a close. If it's a small star (small being "about 10 times more massive than our sun"), it collapses into an incredibly dense "zombie star," known as a neutron star. If it's a big star, it collapses into a black hole. Both are well-known and well-studied objects, but they still contain many mysteries. 

For one, we can't see inside them. This is a much-discussed trait of black holes. Their gravity is so strong that when light gets pulled in -- past the so-called event horizon -- it never comes back out. But scientists also don't know what is going on in the heart of a neutron star. They suspect some truly weird physics could be occurring within both objects. The laws of physics seem to break down inside them.

Observing the objects via gravitational waves is a "kind of stellar paleontology," according to Smith, because it can tell us about their evolutionary history and the environments they form in. 

The chirps are central to this. When US-based LIGO and Italy-based Virgo detect a "chirp," they are looking back through time. Within the chirp is a bunch of information that can tell astrophysicists how massive the colliding objects are and the way they spin. This information is critical to understanding how the two objects came to be locked in a death dance with each other.

"By studying these systems, we get to know a lot more about the life and death of black holes and neutron stars in these binary systems," Scott said.

Star stuff

GW200105, the chirp detected on Jan. 5, 2020, and GW200115, the chirp detected on Jan. 15, 2020, are similar events but the objects that collided have slightly different properties. Those stuffy scientific names are rather confusing, so we've dubbed them Lenny (GW200105) and Carl (GW200115).

The researchers say that Lenny is the result of a black hole about nine times as massive as the sun colliding with a neutron star about 1.9 times as massive as the sun. Carl came via a black hole about six times as massive as the sun merging with a neutron star about 1.5 times as massive as the sun. Lenny and Carl are completely different beasts in the present day. The mergers occurred almost a billion years ago far from the Earth, and the chirps only recently reached us.

When we say "collide" or "merge" here, we're not entirely sure what happened when the two objects finally came together. For a long time, they circled each other, trapped by the other's gravity. Eventually, they came together. Scott describes Lenny and Carl as "a bit like Pac-Man," with the black hole swallowing up the neutron star. 

Another artistic rendition of a black hole and neutron star merger with the black hole stealing material from its counterpart.

LIGO-India/Soheb Mandhai

There's also the possibility the black hole "shreds" the neutron star in a process known as tidal disruption. In this scenario, the black hole would rip material from the surface of the neutron star and steal it, creating a disk of debris around the event horizon. "That should produce an electromagnetic signal," Scott said. 

And a shredded neutron star is a goldmine for astrophysicists. You can't make the material present in a neutron star in a laboratory and study it, so these types of events may open a window to understand what's happening inside them. 

"By watching how a neutron star is pulled apart by a black hole, we are beginning to learn about how matter behaves in its most dense state," said Eric Thrane, an astrophysicist at Monash University and member of the LIGO collaboration. With enough gravitational wave detections, we may be able to decode their properties.

That makes Lenny and Carl the first of many black hole-neutron star mergers helping shed light on the most extreme objects in our universe.

"These observations may one day reveal new laws of nature," Smith said.

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2021-06-29 23:36:08Z
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Clouds of Venus Too Dry to Sustain Even Extremophile Life Forms, Study Says | Planetary Science, Space Exploration - Sci-News.com

The recent suggestion of phosphine gas in the atmosphere of Venus has regenerated interest in the idea of life in clouds; however, such analyses usually neglect the role of water activity, which is a measure of the relative availability of water, in habitability. In a new study in the journal Nature Astronomy, planetary researchers computed the water activity within the clouds of Venus and other solar system planets from observations of temperature and water-vapor abundance; they found that the Venusian water activity was more than a hundred times below the lower limit at which life can exist on Earth; however, Jupiter’s clouds had a high enough concentration of water, as well as the correct temperature, for Earth-like life to exist there.

This composite image, taken by JAXA’s Akatsuki spacecraft, shows Venus. Image credit: JAXA / ISAS / DARTS / Damia Bouic.

“The recent suggestions of biogenic substances, such as phosphine in the Venusian clouds, continuing a history of speculation about life on Venus,” said senior author Professor Christopher McKay, a planetary scientist in the Space Science Division at NASA’s Ames Research Center, and his colleagues.

“The surface of Venus is considered too hot for organic life forms but the lower cloud layer, at an altitude of 40 to 70 km (25-43.5 miles), has a temperature range that makes it potentially habitable based on our knowledge of terrestrial-type life.”

“Earlier studies have suggested the lack of liquid water, or at least the low availability of water, as a potential barrier to life.”

“Although several recent analyses have queried whether adequate water is available, they also propose active cellular metabolism in the sulfuric acid-rich droplets of the Venusian atmosphere.”

Water activity, measured on a scale of 0 to 1, is equivalent to the relative humidity, or availability of water, in a planet’s atmosphere.

The water activity of an environment can considerably affect organisms, including those that are capable of living in extreme environments, known as extremophiles.

Earth-like life requires a water activity of at least 0.585 for metabolism and reproduction to take place.

“We derive water activity of atmospheres without a model of any sort, based only on direct observations of pressure, temperature, and water concentration,” Professor McKay said.

In the study, the researchers calculated the limit for life due to water activity within the clouds of Venus and other planets in the Solar System.

They found that droplets of sulfuric acid reduce the water activity of Venus’s clouds to below 0.004, more than 100 times less than the limit for life.

Comparatively, the representative water activity in the Martian clouds is 0.537, which is slightly below the habitable range for life and similar to that of the second layer, or stratosphere, of the Earth’s atmosphere.

The lowest atmospheric layer of Earth, the troposphere, is, however, permissible for life.

Jupiter’s atmosphere has a biologically permissive water activity of greater than 0.585 for temperatures between minus 10 degrees Celsius and 40 degrees Celsius (14-104 degrees Fahrenheit), although factors such as cloud composition may limit habitability.

“Our research shows that the sulfuric acid clouds in Venus have too little water for active life to exist, based on what we know of life on Earth,” said lead author Dr. John Hallsworth, a researcher in the Institute for Global Food Security at Queen’s University Belfast.

“We have also found that the conditions of water and temperature within Jupiter’s clouds could allow microbial-type life to subsist, assuming that other requirements such as nutrients are present.”

“The search for extraterrestrial life has sometimes been a bit simplistic in its attitude to water,” said co-author Dr. Philip Ball, a researcher based in London, UK.

“As our work shows, it’s not enough to say that liquid water equates with habitability.”

“We’ve got to think too about how Earth-like organisms actually use it — which shows us that we then have to ask how much of the water is actually available for those biological uses.”

“We have also performed calculations for Mars and Earth and show that these calculations can be done for planets outside our Solar System,” Dr. Hallsworth said.

“While our research doesn’t claim that alien (microbial-type) life does exist on other planets in our Solar System, it shows that if the water activity and other conditions are right, then such life could exist in places where we haven’t previously been looking.”

_____

J.E. Hallsworth et al. Water activity in Venus’s uninhabitable clouds and other planetary atmospheres. Nat Astron, published online June 28, 2021; doi: 10.1038/s41550-021-01391-3

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2021-06-29 20:51:04Z
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NASA may have finally solved a Mars methane mystery - CNET

NASA's Curiosity rover snapped this selfie in 2020.

NASA/JPL-Caltech/MSSS

Methane. On Earth, it's the stuff of cow farts and burps. On Mars, it's the stuff of mysteries. Scientists have been puzzling over methane readings from Mars, and NASA may be a step closer to figuring out what's going on with the gas on the red planet. It turns out the time of day has a big impact on methane detections.

Methane is particularly intriguing because it can be a byproduct of living things, including microbes. Researchers are trying to work out if Mars once hosted microbial life, or if microbes might possibly survive there now. But don't get too hyped; methane can also have a geologic origin.

What's weird about methane on the red planet is that NASA's Curiosity rover has detected the gas near the surface in the Gale Crater, but the European Space Agency's ExoMars Trace Gas Orbiter spacecraft isn't seeing methane higher up in the atmosphere. So what's going on?

Curiosity's Tunable Laser Spectrometer instrument is part of its Sample Analysis at Mars system, essentially a portable chemistry lab. Usually, TLS detects a small amount of methane NASA describes as "equivalent to about a pinch of salt diluted in an Olympic-size swimming pool." In 2019, TLS notably detected a considerable spike in methane levels.

The ExoMars orbiter, which arrived at Mars in 2016, hasn't been seeing what Curiosity sees. "But when the European team announced that it saw no methane, I was definitely shocked," TLS instrument lead Chris Webster said in a NASA statement on Tuesday.

Mars pits: Gaze into the abyss with these wild NASA images

See all photos

The discrepancy may come down to the times of day when the orbiter and rover work. The power-hungry TLS on the rover operates at night so it doesn't conflict with other instruments. The orbiter makes its detections during the day when it has sunlight to help it. What may be happening is that methane pools near the surface during calm nights and dissipates during the day, making it invisible to the spacecraft.

The Curiosity team tested this idea by taking daytime methane measurements, and indeed the gas disappeared during the day. The researchers published their findings today in the Astronomy and Astrophysics journal (PDF link).

While one methane mystery may have an explanation, another gassy conundrum lingers. NASA is still trying to sort out the "global methane puzzle at Mars." Methane released from Mars craters should remain stable enough -- and accumulate in the atmosphere enough -- for detection by the Trace Gas Orbiter. 

Scientists are now looking into what might be destroying the methane. "We need to determine whether there's a faster destruction mechanism than normal to fully reconcile the data sets from the rover and the orbiter," said Webster. Until then, Mars methane will remain an enigma.

Follow CNET's 2021 Space Calendar to stay up to date with all the latest space news this year. You can even add it to your own Google Calendar.   

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2021-06-29 19:12:00Z
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