Tag: science

Blue Origin distributes $19 million of the $28 million earned for its July 20th suborbital flight

1:23 pm

Blue Origin today announced the nineteen non-profits that will receive $1 million each, taken from the $28 million that a single as-yet unnamed person is paying to fly with Jeff Bezos on the first commercial suborbital manned flight of New Shepard on July 20, 2021.

All of the organizations are advocates for space exploration. A majority foster education for the young. Two are pro-women, pushing gender politics in space.

The remaining $9 million will be used by Blue Origin’s non-profit to encourage space-focused curriculum and its project to encourage people to send postcards into suborbital space on its New Shepard spacecraft.

All in all the list of recipients surprised me. I had expected this money to go to many of the very leftist environmental groups that Jeff Bezos loves. Instead, the list is entirely space-focused, though it does tend to favor organizations that mostly aim to maintain the status quo of a big government space program or push for gender or racial politics. That there is a large variety of organizations that push many different approaches to encouraging space exploration however is refreshing.

Nonetheless, except for a few that actually educate children, most are advocacy groups. Compare that to the charity being produced by SpaceX’s first manned commercial flight in September, dubbed Inspiration4. That flight is pumping big bucks directly into St. Jude’s Research Hospital to help it cure children from cancer.

Which do you think is doing more for the world?

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Hubble update: Engineers pinpoint issue, prepare to fix it

12:38 pm

In an update today on the status for bringing the Hubble Space Telescope back into science operations, the engineers say they think they have pinpointed the failed unit, and are ready to do the switch to a backup.

A series of multi-day tests, which included attempts to restart and reconfigure the computer and the backup computer, were not successful, but the information gathered from those activities has led the Hubble team to determine that the possible cause of the problem is in the Power Control Unit (PCU).

The PCU also resides on the SI C&DH unit. It ensures a steady voltage supply to the payload computer’s hardware. The PCU contains a power regulator that provides a constant five volts of electricity to the payload computer and its memory. A secondary protection circuit senses the voltage levels leaving the power regulator. If the voltage falls below or exceeds allowable levels, this secondary circuit tells the payload computer that it should cease operations. The team’s analysis suggests that either the voltage level from the regulator is outside of acceptable levels (thereby tripping the secondary protection circuit), or the secondary protection circuit has degraded over time and is stuck in this inhibit state.

Because no ground commands were able to reset the PCU, the Hubble team will be switching over to the backup side of the SI C&DH unit that contains the backup PCU. All testing of procedures for the switch and associated reviews have been completed, and NASA management has given approval to proceed. The switch will begin Thursday, July 15, and, if successful, it will take several days to completely return the observatory to normal science operations.

Engineers did a similar switch in 2008, so they are very confident it will work this time also. However, once done, the telescope will no longer have backups for any of these computer modules. The next failure in any of them will shut the telescope down, for good.

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Craters on Ganymede’s striped surface

11:27 am

Craters on Ganymede
Click for full image.

Cool image time! The photo to the right, cropped to post here, is a color enhanced section taken from of one of the images taken by Juno when it did a close fly-by of the Jupiter moon Ganymede back on June 7, 2021.

The enhancement was done by citizen scientist Navaneeth Krishnan, using a wider Juno image of Ganymeded enhanced by citizen scientist Kevin Gill. That wider image is below, and marks the area covered by this first image with a white box.

In this one picture we can see many of the geological mysteries that have puzzled scientists since the Galileo orbiter first took close-up images back in the 1990s. We can see patches of grooved terrain with the grooves in the different patches often oriented differently. We can also see bright and dark patches that while they overlay the grooved terrain they bear no correspondence to those grooved patches. And on top of it all are these small craters, impacts that obviously occurred after the formation of the grooves.
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Clashing layers in Mars’ largest canyon

1:20 pm

Clashing layers on a mountain slope on Mars
Click for full image.

Cool image time! The photo to the right, rotated, cropped, and reduced to post here, was taken on May 27, 2021 by the high resolution camera on Mars Reconnaissance Orbiter (MRO), and shows the clash of different layers on the western slope of a mountain within Mars’ largest canyon, Valles Marineris.

The scientist have labeled this a “possible angular unconformity.” In geology an unconformity generally refers to a gap in a series of layers, a period when instead of the layers being deposited they are being eroded away, leaving no record for that time period. An angular unconformity adds tilting to the older layers, which after erosion are then covered by new layers that are oriented somewhat differently.

Based on these definitions, what the scientists suspect is that the brighter layers to the left and lower down the mountain are older. After a period of erosion new layers were deposited on top at a different angle, forming the stripe of layers going from center left up to center right.

The swirly nature of the material on the top of the ridge suggests to me that these layers might be volcanic in nature, but that’s a pure uneducated guess. What some scientists do believe (but have not yet conclusively proven) is that the lower older layers are sediments laid down by an ancient lake that once filled the canyon here.

The overview map below provides a wider view and some context.
» Read more

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Scientists successfully predict resumption of bursts from magnetar

12:14 pm

The uncertainty of science: Though they have no real idea why it happens, scientists have now successfully predicted the resumption of energetic bursts coming from a magnetar and according to schedule.

The researchers — Grossan and theoretical physicist and cosmologist Eric Linder from SSL and the Berkeley Center for Cosmological Physics and postdoctoral fellow Mikhail Denissenya from Nazarbayev University in Kazakhstan — discovered the pattern last year in bursts from a soft gamma repeater, SGR1935+2154, that is a magnetar, a prolific source of soft or lower energy gamma ray bursts and the only known source of fast radio bursts within our Milky Way galaxy. They found that the object emits bursts randomly, but only within regular four-month windows of time, each active window separated by three months of inactivity.

On March 19, the team uploaded a preprint claiming “periodic windowed behavior” in soft gamma bursts from SGR1935+2154 and predicted that these bursts would start up again after June 1 — following a three month hiatus — and could occur throughout a four-month window ending Oct. 7.

On June 24, three weeks into the window of activity, the first new burst from SGR1935+2154 was observed after the predicted three month gap, and nearly a dozen more bursts have been observed since, including one on July 6.

They made this prediction based on data going back to 2014 that showed the three-month-off/four-month-on pattern.

As to why this pattern exists, they presently have no idea. Theories have been proposed, such as starquakes activated by the magnetar’s fast rotation or blocking clouds of gas, but none are really very convincing, or are backed with enough data.

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Israeli nonprofit that built Beresheet-1 raises $70 million for Beresheet-2

8:23 am

SpaceIL, the Israeli nonprofit company that built the Beresheet-1 lunar lander/rover that crashed just before landing in 2019 has now raised $70 million of the $100 million it needs to build Beresheet-2.

SpaceIL said the new pledges means that it has raised almost all of the $100 million it estimates is needed for the mission to meet its 2024 launch target. SpaceIL said the funding would come from South African-Israeli billionaire Morris Kahn, who bankrolled much of the first mission, French-Israeli billionaire Patrick Drahi and South African philanthropist Martin Moshal, co-founder of venture capital firm Entree Capital.

A number of the engineers who helped build the first Beresheet have since moved on, forming their own company as well as getting hired by the American startup rocket company Firefly. Still, there is no reason Beresheet-2 cannot be built and flown, especially if SpaceIL focuses on rebuilding it rather than redesigning something new. They came very close to a success, and probably only need some tweaking to make the next attempt succeed.

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Ingenuity’s view of Jezero Crater during its 9th flight

11:57 am

Ingenuity looks across Jezero Crater
Click for full image.

Overview map
Click for interactive map.

Cool image time! The photo above, cropped, enhanced, and reduced to post here, was taken on July 5, 2021, about thirty seconds after Ingenuity had taken off on its 9th flight on Mars. I have increased the contrast slightly to bring out the features. This is a raw image, so I do not think the colors are accurate, and I also do not know why the middle of the image is brighter than the edges.

The red lines on the map to the right indicates the general area this image captures. Essentially, once the helicopter reached its flying altitude after liftoff the engineers had it tilt so that it could see the route it was about to take to the southwest. As they noted in their description of this flight,

We began by dipping into what looks like a heavily eroded crater, then continued to descend over sloped and undulating terrain before climbing again to emerge on a flat plain to the southwest.

I think that crater is visible on the left edge of this picture.

So far 180 raw images from Ingenuity have arrived at JPL. There might be a few more, but I think this is the bulk from the flight. Of these, all but nine are black and white and point straight down. The nine color images seem tilted up towards the horizon to various degrees, though the image above is the only one that captures the horizon itself and the distance mountains of Jezero Crater’s rim.

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China targets 2024 for next lunar sample return mission

9:42 am

The new colonial movement: China’s next robotic lunar sample return mission, called Chang’e-6 and targeted for a 2024 launch, will also attempt to bring back the first samples from the far side of the Moon.

Hu Hao, chief engineer of the China Lunar Exploration and Space Engineering Center, announced in a statement released on China’s national space day in April this year that the Chang’e 6 probe, consisting of an orbiter, lander, lunar ascent vehicle and reentry capsule, will target the South Pole-Aitken (SPA) basin.The SPA basin is a colossal, ancient impact crater roughly 1,550 miles (2,500 kilometers) in diameter that covers almost a quarter of the moon’s far side. The impact basin, considered to be the oldest on the moon, holds vital clues about the history of the moon and the solar system, according to a new report.

The precise spot for landing has not been revealed. Since the basin is so large and covers the Moon’s south pole, the mission could land in that region where ice is thought to possibly exist in the permanently shadowed floors of some craters. Whether they would attempt a landing in one of those craters is presently unknown, though unlikely because of the technical challenge.

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Curiosity looks across at the alien landscape of Gale Crater

2:25 pm

Curiosity's view across Gale Crater
Click for full image.

Most of the images from Curiosity that I have posted recently have been of the spectacular mountain scenery looking south at Mount Sharp itself. Today’s cool image, taken on July 6, 2021 by the rover’s right navigation camera and cropped to post here, instead looks north, out across the floor of Gale Crater to its distant rim about twenty miles away.

The rover is likely not to move for a week or so, as it has just completed drilling its first drillhole since it moved up into the next geological layer, dubbed the sulfate unit. Because of this they have been using the rover’s cameras to take a lot of pictures of the surrounding terrain, including several high resolution mosaics.

The two overview maps below show what the cool image above is looking at.
» Read more

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Engineers successful complete simulation of Hubble repair

12:30 pm

Though the details released are sparse, engineers working to get the Hubble Space Telescope back in operation since it shut down due to a computer problem in mid-June report today that they have successfully completed a simulation of the procedures they need to do to fix the problem.

This is their entire report:

[The engineers] successfully completed a test of procedures that would be used to switch to backup hardware on Hubble in response to the payload computer problem. This switch could occur next week after further preparations and reviews.

Apparently, because the switch to backup hardware requires switching more than one unit, the sequence is important and following it correctly is critical. It appears they have now determined the correct sequence and will attempt it on Hubble next week.

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Update on Ingenuity’s 9th flight

9:55 am

Ingenuity's 9th flight
Click for interactive map

Ingenuity’s engineering team late yesterday posted an update on the helicopter’s successful 9th flight on July 5th, describing in detail the changes they made to their software that made the challenging flight possible.

The changes were required because the helicopter flew for the first time over much rougher terrain then initially planned, as shown by the map to the right.

Flight 9 was not like the flights that came before it. It broke our records for flight duration and cruise speed, and it nearly quadrupled the distance flown between two airfields. But what really set the flight apart was the terrain that Ingenuity had to negotiate during its 2 minutes and 46 seconds in the air – an area called “Séítah” that would be difficult to traverse with a ground vehicle like the Perseverance rover. This flight was also explicitly designed to have science value by providing the first close view of major science targets that the rover will not reach for quite some time.

In other words, Ingenuity flew for the first time over terrain that Perseverance cannot drive to, recording images from above of surface features beyond the rover’s range.

We began by dipping into what looks like a heavily eroded crater, then continued to descend over sloped and undulating terrain before climbing again to emerge on a flat plain to the southwest.

The images of that rough terrain have not yet been downloaded to Earth, but will be in the next week.

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Springtime on Martian dunes near the north pole

1:42 pm

Dunes near the Martian north pole, in the spring

Cool image time! The photo to the right, rotated and cropped to post here, was taken by the high resolution camera on Mars Reconnaissance Orbiter (MRO) on April 27, 2021. It shows a strange scattering of dunes on a flat plain. The red at the top of each dune probably indicates exposed dust and sand. The white fringe is likely either water frost or the leftover mantle of dry ice that is deposited in the polar regions each winter down to 60 degrees latitude, and disappears with the coming of spring, sublimating back into carbon dioxide gas.

There are a lot of puzzles here. The overview map below provides some context, but only some.
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NOAA struggles with concept of letting private commercial space build its satellites

9:49 am

Capitalism in space? An article today in Space News, “NOAA to take first step toward a small satellite constellation”, describes at great length NOAA’s recent effort to rethink how it builds its weather satellites, shifting from large and expensive single satellites launched years apart to constellations of smallsats that provide more redundancy and are cheaper and easier to replace.

What the article misses, as does NOAA apparently, is that this shift should not be designed by NOAA at all. During the Trump administration there was pressure on this agency to do what NASA had, stop designing and building its satellites but instead become a customer that hires private satellite companies to do it instead.

Not much came of that pressure. NOAA hired one private company to study the idea of building a private satellite to observe the Sun. It also awarded three companies experimental contracts to provide NOAA weather data from already orbiting smallsats.

That was it. NOAA made no other attempts to encourage private companies to design and build weather satellites for it, even as it struggled to get its own satellites off the ground. The second new GOES satellite in a constellation of four for providing global weather coverage failed almost immediately after launch in 2018. Overall, that constellation is expected to cost $11 billion, $4 billion more than initially budgeted. And it is years behind schedule.

What the article above suggests is that, with the Trump administration gone, NOAA has now abandoned the effort to transition to privately-built weather satellites. Instead the article describes at great length the effort by NOAA to redesign its satellites from big, rare, and costly to small, frequent, and cheap.

This effort will fail. Government agencies like NOAA are incapable of accomplishing such a task. They do not think in terms of profit, and keeping costs down to maximize those profits. Instead, such government institutions see high costs as beneficial, as they pump more money into their operations.

Until elected officials force NOAA to change, it will not, and its weather satellites will continue to be late, expensive, and untrustworthy. Sadly, the elected officials we have today, especially in the Biden administration, are not going to do that. They are as satisfied with the present situation as NOAA is.

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Sublimating scallops on Mars

2:05 pm

Giant scallop on Mars
Click for full image.

Today’s cool image, shown in a rotated, cropped, and reduced version to the right, gives us a close-up look at one of the giant scallops found in the high mid-latitudes of the northern lowland plains of Mars, specifically in Utopia Basin north of the landing sites of both Perseverance and Zhurong. In fact, this particular image is only a few miles north of one of my previous cool images, Giant scallops on Mars, posted in December 2019.

The image was taken on February 3, 2021 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). While such scallops are not unusual in the mid-latitudes, their formation process is not well understood. As I noted in the 2019 post, ” scientists believe [pdf] the formation process is related to the sublimation of underground ice.”

According to [one hypothesis] scallop formation should be ongoing at the present time. Sublimation of interstitial ice could induce a collapse of material, initially as a small pit, then growing [away from the equator] because of greater solar heating on [that] side. Nearby scallops would coalesce together as can be seen to have occurred.

This hypothesis is not proven, and today’s cool image raises questions about it. Though the bright material at its center suggests exposed ice, supporting the idea that sublimation of ice near the surface created the scallop, the scallop scarps seem more extended and distinct to the south, not the north as this hypothesis proposes. Sunlight should hit the northern scarps more, which suggests they should retreat more instead of the southern scarp.

The overview map below provides the context.
» Read more

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First images from Ingenuity’s 9th flight today

10:20 am

Ingenuity landing, July 5, 2021

Ingenuity has apparently completed its 9th flight on Mars, its most challenging yet attempted. Based on the six images so far released from that flight, all taking during its landing, it appears the flight was successful. Or at least, the helicopter landed without incident or damage.

The photo to the right was the last picture taken just before touch down. From the caption:

NASA’s Ingenuity Mars Helicopter acquired this image using its navigation camera. This camera is mounted in the helicopter’s fuselage and pointed directly downward to track the ground during flight.

The dark shadow of the helicopter is clearly visible. If you want to see the entire sequence of six images, go to the Ingenuity raw image website and pick the “latest images” filter in the right column. At present it shows this sequence, though I am certain as the day passes images from the entire flight will start appearing.

As noted at the first link above, the flight was to be more than twice as long as any previous flight while flying over the roughest terrain. There was the real risk that its software would become confused by that terrain.

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Sun unleashes strongest solar flare since last solar maximum

9:54 am

X1 solar flare as seen by Solar Dynamics Observatory

On July 3, 2021 the Sun emitted the first X-class solar flare of the rising present solar maximum, the first such flare since September 2017 during the previous maximum.

This flare is classified as an X1.5-class flare. X-class denotes the most intense flares, while the number provides more information about its strength. An X2 is twice as intense as an X1, an X3 is three times as intense, etc.

The image to the right was taken by the orbiting Solar Dynamics Observatory (SDO), designed to monitor the Sun continuously and catch such events.

More information here. The flare caused some disturbances to various radio instruments, though nothing that resulted in any serious consequences.

What the flare did demonstrate is that the Sun is definitely ramping up to solar maximum. In fact, the Sun has not been blank, with no sunspots on its facing hemisphere, since May 6th, the longest such stretch since the last solar maximum.

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Sunspot update: The hot streak continues

8:01 am

This past weekend NOAA released its monthly update of its graph showing the Sun’s sunspot activity, with the new update covering the period through the end of June 2021. As I have done since I began this website eleven years ago, I post that monthly graph below, annotated to show the previous solar cycle predictions and thus provide context.

In June the hot streak of sunspot activity exceeding the prediction of NOAA’s solar science panel continued, with activity rising again after a tiny dip in May. Except for two months, since 2019 the number of sunspots each month has consistently exceeded the prediction. Furthermore, the ramp up of activity has been faster than expected.
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Next Ingenuity flight to push envelope significantly

11:20 am

Ingenuity's 9th flight plan
Click for full image.

The engineers running the Mars helicopter Ingenuity revealed today that they will be attempting their most ambitious flight for the helicopter’s ninth flight, presently scheduled for no earlier than July 4th.

I have annotated the map to the right to show Ingenuity’s present position and its approximate landing area.

Without question this flight will be the riskiest taken by Ingenuity so far, more than doubling the flight distance achieved on any previous flight. More important, it will be flying over terrain far rougher than it was initially designed for.
» Read more

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More parachute problems for Europe’s Franklin Mars rover

10:11 am

During a parachute drop test in late June, following a redesign of the parachute with U.S. help, engineers for the ExoMars Rosalind Franklin Mars rover found the chute still experienced problems that tore it during deployment.

They actually performed two drop tests, a day apart, using two different parachutes, with the first test apparently going off without a hitch. However, according to the press release:

“The performance of the second main parachute was not perfect but much improved thanks to the adjustments made to the bag and canopy. After a smooth extraction from the bag, we experienced an unexpected detachment of the pilot chute during final inflation. This likely means that the main parachute canopy suffered extra pressure in certain parts. This created a tear that was contained by a Kevlar reinforcement ring. Despite that, it fulfilled its expected deceleration and the descent module was recovered in good state.”

I have embedded below the fold the only video released by the European Space Agency. It is not clear whether this is from the first or second test. Near the end it appears that the pilot chute above the main chute might be separated, but the video ends before that can be confirmed.

Though ESA has apparently improved the chute’s performance significantly since its earlier failures that contributed to the delay of ExoMars from last year to 2022, they still haven’t gotten the chute completely right. Fortunately they still have time to get it fixed before that ’22 launch.
» Read more

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Perseverance’s most recent view of Jezero Crater

10:30 am

Panorama by Perseverance, Sol 130, July 2, 2021
Click for full resolution.

Overview map
Click for interactive map.

Cool image time! The panorama above, reduced to post here, is made from two navigation camera images on the Mars rover Perseverance, found here and here.

The map to the right, taken from the “Where is Perseverance?” website and annotated further by me, shows with the yellow lines what I think (but am not sure) is the area seen in the panorama.

The navigation cameras on Perseverance are more wide angle than the navigation cameras on Curiosity, in order to cover a larger area. They thus produce a slight fisheye distortion, illustrated by the curve of the horizon.

The large mountain in the center right is likely the crater rim. You can also see the knobs to the left as indicated on the overview map. The rover is now about halfway to the southernmost planned spot it is expected to reach within the floor of Jezero Crater, which is about a half to three quarters of a mile further south.

The terrain seems quite desolate and barren, which of course is no surprise, because that is what it is like on all of the surface of Mars. No plant life, just rocks and dirt. While Curiosity is now in the mountains, Perseverance remains on the crater floor, so the points of interest (from the mere tourist’s perspective) are small or far away.

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Al-Amal detects Martian aurora

10:11 am

Aurora on Mars

The United Arab Emirates Al-Amal Mars orbiter has detected evidence of a Martian aurora that would be visible at night for short periods.

The ultraviolet images to the right have been reduced slightly to post here.

These three images of atomic oxygen emission at a wavelength of 103.4 nm from the planet Mars were obtained by the Emirates Mars Ultraviolet Spectrometer instrument on 22 April, 23 April, and 06 May 2021 respectively. The full set of data collected during these observations include far and extreme ultraviolet auroral emissions which have never been imaged before at Mars. The beacons of light that stand out against the dark nightside disk are highly structured discrete aurora, which traces out where energetic particles excite the atmosphere after being funneled down by a patchy network of crustal magnetic fields that originate from minerals on the surface of Mars.

Though Mars does not have a magnetic field, it is believed that sections of the planet’s crust are magnetized, and under the right conditions can guide the charged particles from the Sun’s solar wind to the night side to hit the atmosphere where they break up and produce the aurora. Because there is no magnetic field however the particles are not guided by the field lines to the poles, but to different spots at all latitudes, depending on circumstances.

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Scientists solve methane data conflict on Mars

9:10 am

Using the methane detector on the rover Curiosity scientists now think they have solved the mystery why Curiosity has detected methane in the atmosphere near the surface while Europe’s Trace Gas Orbiter fails to detect any methane at all.

[Planetary scientist John E. Moores from York University in Toronto], as well as other Curiosity team members studying wind patterns in Gale Crater, hypothesized that the discrepancy between methane measurements comes down to the time of day they’re taken. Because it needs a lot of power, TLS [Curiosity’s methane detector] operates mostly at night when no other Curiosity instruments are working. The Martian atmosphere is calm at night, Moores noted, so the methane seeping from the ground builds up near the surface where Curiosity can detect it.

The Trace Gas Orbiter, on the other hand, requires sunlight to pinpoint methane about 3 miles, or 5 kilometers, above the surface. “Any atmosphere near a planet’s surface goes through a cycle during the day,” Moores said. Heat from the Sun churns the atmosphere as warm air rises and cool air sinks. Thus, 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. “So I realized no instrument, especially an orbiting one, would see anything,” Moores said.

Immediately, the Curiosity team decided to test Moores’ prediction by collecting the first high-precision daytime measurements. TLS measured methane consecutively over the course of one Martian day, bracketing one nighttime measurement with two daytime ones. With each experiment, SAM sucked in Martian air for two hours, continuously removing the carbon dioxide, which makes up 95% of the planet’s atmosphere. This left a concentrated sample of methane that TLS could easily measure by passing an infrared laser beam through it many times, one that’s tuned to use a precise wavelength of light that is absorbed by methane.

“John predicted that methane should effectively go down to zero during the day, and our two daytime measurements confirmed that,” said Paul Mahaffy, the principal investigator of SAM, who’s based at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. TLS’ nighttime measurement fit neatly within the average the team had already established. “So that’s one way of putting to bed this big discrepancy,” Mahaffy said.

While this explains the data conflict, it does not yet explain where the methane is coming from. It is suspected it is coming from underground, but why and from what is still unclear. Nor do scientists yet understand why it doesn’t accumulate enough in the atmosphere for Trace Gas Orbiter to detect it. Something is causing the methane to break up sooner than expected.

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Hubble update: Engineers narrow possible failed hardware to one of two units

5:09 pm

Engineers working to pinpoint the cause of the computer hardware issue that has placed the Hubble Space Telescope in safe mode since June 13th have now narrowed the possible failed hardware to one of two units.

The source of the computer problem lies in the Science Instrument Command and Data Handling (SI C&DH) unit, where the payload computer resides. A few hardware pieces on the SI C&DH could be the culprit(s).

The team is currently scrutinizing the Command Unit/Science Data Formatter (CU/SDF), which sends and formats commands and data. They are also looking at a power regulator within the Power Control Unit, which is designed to ensure a steady voltage supply to the payload computer’s hardware. If one of these systems is determined to be the likely cause, the team must complete a more complicated operations procedure to switch to the backup units. This procedure would be more complex and riskier than those the team executed last week, which involved switching to the backup payload computer hardware and memory modules. To switch to the backup CU/SDF or power regulator, several other hardware boxes on the spacecraft must also be switched due to the way they are connected to the SI C&DH unit.

Over the next week or so, the team will review and update all of the operations procedures, commands and other related items necessary to perform the switch to backup hardware. They will then test their execution against a high-fidelity simulator.

The team performed a similar switch in 2008, which allowed Hubble to continue normal science operations after a CU/SDF module failed.

That such a switch was done successfully in the past is a very hopeful sign. However, it sounds as though they are not 100% sure they have pinpointed the actual issue, which means that this switch still might not fix the problem.

We can only wait and hope. And even if the fix works, Hubble will no longer have working backup units for these pieces of hardware. Should any of the backup that are now being activated fail, the telescope will fail, and this time it won’t be fixable with the equipment on board.

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Astronomers detect a white dwarf that is both the smallest and most massive ever found

10:04 am

Using an array of telescopes on the ground and in space, astronomers have discovered a white dwarf star that is both the smallest ever found while also being the most massive.

White dwarfs are the collapsed remnants of stars that were once about eight times the mass of our Sun or lighter. Our Sun, for example, after it first puffs up into a red giant in about 5 billion years, will ultimately slough off its outer layers and shrink down into a compact white dwarf. About 97 percent of all stars become white dwarfs.

While our Sun is alone in space without a stellar partner, many stars orbit around each other in pairs. The stars grow old together, and if they are both less than eight solar-masses, they will both evolve into white dwarfs.

The new discovery provides an example of what can happen after this phase. The pair of white dwarfs, which spiral around each other, lose energy in the form of gravitational waves and ultimately merge. If the dead stars are massive enough, they explode in what is called a type Ia supernova. But if they are below a certain mass threshold, they combine together into a new white dwarf that is heavier than either progenitor star. This process of merging boosts the magnetic field of that star and speeds up its rotation compared to that of the progenitors.

Astronomers say that the newfound tiny white dwarf, named ZTF J1901+1458, took the latter route of evolution; its progenitors merged and produced a white dwarf 1.35 times the mass of our Sun. The white dwarf has an extreme magnetic field almost 1 billion times stronger than our Sun’s and whips around on its axis at a frenzied pace of one revolution every seven minutes (the zippiest white dwarf known, called EPIC 228939929, rotates every 5.3 minutes).

Based on their present understanding of stellar evolution, single white dwarfs do not form from stars with more than 1.3 solar masses. Stars with greater masses instead become neutron stars, or black holes. To get a white dwarf of 1.35 masses thus requires a merger of two white dwarfs, but it also means that the resulting dwarf could be unstable and could collapse into a neutron star at some point. The data also suggests that this merger process might be how a large number of neutron stars actually form.

The dwarf is also the smallest ever found, with a diameter of 2,670 miles, because the larger masses squeezes it into a tighter space.

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Dust covering solar panels threatens to end InSight mission

9:52 am

The InSight science team has revealed that the amount of dust that presently covers the solar panels on the Mars lander has now reduced their available power by about 80%, and if a dust devil doesn’t soon blow the dust off they will have to shut the spacecraft down sometime in the next ten months.

“The dust accumulation on the solar arrays has been considerable. We have about 80% obscuration of the arrays,” said Bruce Banerdt, principal investigator for the InSight mission at NASA’s Jet Propulsion Laboratory (JPL) in Southern California, according to SpaceNews.

Banerdt showed the impact of the declining power levels during a June 21 meeting of NASA’s Mars Exploration Program Analysis Group. When InSight landed near the Martian equator in November 2018, he said, the robot was generating roughly 5,000 watt-hours of power. Today that level is less than 700 watt-hours.

None of this is a surprise. Both the Opportunity and Spirit rovers faced the same problems. Both however were able to recover because periodically a dust devil would fly over the rover and clear the dust from the solar panels.

InSight however has not so far been lucky. While it has seen many nearby dust devils with its camera, none has come close enough to sweep the solar panels clean.

As the power has declined they have shut off various systems in order to keep the lander’s prime instrument, its seismometer, operating continuously. Engineers have also been using the scoop on the lander’s robot arm to try to dislodge some of the dust, with only a very very limited success. If the panels are not cleared soon, however, engineers will eventually be forced to shut everything down.

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Gravitational wave detectors see two different black holes as they swallowed a neutron star

9:41 am

Astronomers using three different gravitational wave detectors have seen the gravity ripples caused when two different black holes swallowed a nearby neutron star.

The two gravitational-wave events, dubbed GW200105 and GW200115, rippled through detectors only 10 days apart, on January 5, 2020, and January 15, 2020, respectively.

Each merger involved a fairly small black hole (less than 10 Suns in heft) paired with an object between 1½ and 2 solar masses — right in the expected range for neutron stars. Observers caught no glow from the collisions, but given that both crashes happened roughly 900 million light-years away, spotting a flash was improbable, even if one happened — and it likely didn’t: The black holes are large enough that they would have gobbled the neutron stars whole instead of ripping them into bite-size pieces.

Note the time between the detection, in early 2020, and its announcement now, in mid-2021. The data is very complex and filled with a lot of noise, requiring many months of analysis to determine if a detection was made. For example, in a third case one detector was thought to have seen another such merger but scientists remain unsure. It might simply be noise in the system. I point this out to emphasize that thought they are much more confident in these new detections, there remains some uncertainty.

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Comet spewed out an unusual amount of alcohol during solar flyby

1:04 pm

A review of the data gathered when Comet 46P/Wirtanen made its close fly-by of the Sun in 2018 has found that the comet released an unusual amount of alcohol during that flyby.

The data also showed that the temperature of the comet’s coma did not cool as much as expected at larger distances from the comet.

“46P/Wirtanen has one of the highest alcohol-to-aldehyde ratios measured in any comet to date,” said Neil Dello Russo, a cometary scientist at Johns Hopkins University Applied Physics Laboratory and co-author of the study. “This tells us information about how carbon, oxygen, and hydrogen molecules were distributed in the early solar system where Wirtanen formed.”

Keck Observatory data also revealed a strange characteristic. Normally, as comets orbit closer to the Sun, the frozen particles in their nucleus heat up, then boil off, or sublimate, going directly from solid ice to gas, skipping the liquid phase. This process, called outgassing, is what produces the coma – a giant cloak of gas and dust glowing around the comet’s nucleus. As the comet gets even closer to the Sun, solar radiation pushes some of the coma away from the comet, creating the tails.

With comet 46P/Wirtanen however, the team made a strange discovery: Another process beyond solar radiation is mysteriously heating up the comet.

“Interestingly, we found that the temperature measured for water gas in the coma did not decrease significantly with distance from the nucleus, which implies a heating mechanism,” said co-author Erika Gibb, professor and chair of the Department of Physics and Astronomy at University of Missouri–St. Louis.

They have theories about why they got these results, such as a chemical reaction with sunlight or the presence of large ice chunks breaking off the comet that reflect light and increase the ambient temperature of the coma. Nothing is confirmed however.

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Study: Venus’ atmosphere too dry for life

8:43 am

The uncertainty of science: A new study has found that the amount of water in Venus’ atmosphere is too low to support the possibility of life.

On Earth, Hallsworth said, microorganisms can survive and proliferate in droplets of water in the atmosphere when temperatures allow. However, the findings of the new study, based on data from several Venus probes, leave zero chance of anything living in the clouds of Venus, he said.

“Living systems including microorganisms are composed mainly of water and without being hydrated, they can’t be active and are unable to proliferate,” Hallsworth said.

Studies on microorganisms living in extreme conditions on Earth found that life can exist at temperatures as cold as minus 40 degrees Fahrenheit (minus 40 degrees Celsius). For water activity, which is measured on the scale from 0 to 1, the lowest survivable value is 0.585. The water activity level found in the molecules in the Venusian clouds was merely 0.004.

NASA Ames astrobiologist Chris McKay, one of the co-authors of the paper, said in the news conference that the findings of the study were conclusive and the new fleet of space missions currently being prepared for Venus will not change anything about the hope for life on Earth’s closest neighbor.

McKay can be as “conclusive” as he wants, but that really isn’t how science works. While this data is very strong evidence that there is no life on Venus, a result that should be expected given its harsh environment, it can’t preclude for certain the possibility. You can’t prove a negative in science.

At the same time, this paper puts another nail in the coffin of that very weak result, since found even weaker, in September 2020 that suggested the presence of phosphine in the atmosphere that suggested the possibility of life.

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