Tag: science

Yutu-2 heads west!

10:28 am

LRO images of Yutu-2 on the Moon
Click for full image.

A new image from Lunar Reconnaissance Orbiter (LRO) shows the path taken by the Chinese lunar rover Yutu-2 during its second lunar day of travel on the Moon. The LRO images on the right, cropped and reduced in resolution to show here, compares the rovers position at the start and end of February. The white arrow indicates the rover, with its Chang’e-4 lander visible between the three craters to the east. As noted by the LRO science team:

LRO passes over any given place on the Moon at least once every month (in the daylight), allowing the westward progress of the Yutu-2 rover to be seen. At the end of February, Yutu-2 was 69 meters from it’s home base, the Chang’e 4 lander; LROC images show Yutu-2 made 46 meters of westward progress during the month of February.

It appears from these orbital images that they are taking the smoothest route, with the fewest obstacles, away from the lander.

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Hayabusa-2 to take close look at planned explosive impact point on Ryugu

10:14 am

Flight plan for Hayabusa-2's rehearsal

Beginning today Hayabusa-2 will do a two-day close approach of Ryugu in order to get good baseline images of the point on the surface where they will fire an explosive projectile in the first week in April. As they note:

Currently, we have scheduled the small carry-on impactor operation (SCI operation) for the first week in April. The purpose of the SCI operation is to create a crater on the surface of Ryugu, and it is important to be able to compare the asteroid surface before and after the SCI operation.

The graph on the right shows the flight plan. I expect they will do the same for this maneuver as they have done with previous close approaches, and provide real-time images as they happen.

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Streaky Mars: Slope streaks and recurring slope lineae

12:01 pm

New recurring lineae on Mars
Click for source paper [pdf].

Numerous presentations at this week’s 50th Lunar and Planetary Science Conference in Texas have focused on two different changing features on the Martian surface, dubbed slope streaks and recurring slope lineae (or RSLs, an example of an unnecessary and unwieldy acronym that I avoid like the plague).

These apparently are considered two different phenomenon (with some overlap), something I had not recognized previously. For example, one presentation [pdf] this week described slope streaks as:

…gravity-driven dark or light-toned features that form throughout the martian year in high-albedo and low-thermal-inertia equatorial regions of Mars. The distinctive features originate from point sources on slopes steeper than ~20°, follow the topographic gradient, extend or divert around small obstacles, and propagate up to maximum lengths of a few kilometers. The streaks brighten with time, sometimes become brighter than their surroundings, and fade away over timescales of decades. [emphasis mine]

An example can be seen here. This is in contrast to the recurring slope lineae, shown in the image above, which another paper [pdf] described as:

…dark linear features that occur on the surface of steep slopes in the mid-latitudes of Mars. These areas are warm, occasionally exceeding temperatures of 273-320 K. [Lineae] recur over multiple years, growing during warm seasons and fading away during colder seasons. Their apparent temperature dependency raises the possibility that liquid water is involved in their formation. [emphasis mine]

I have highlighted the key differences. While slope streaks are long lived and change slowly, lineae change with the Martian seasons. And the slope streaks appear to exist at lower latitudes. These difference means that the formation process of each must be also different.

The problem is that scientists still don’t know what causes either, though they have many theories, involving both wet and dry processes.

Most of the presentations at the conference this week focused on the recurring lineae, which I suspect is because of their seasonal aspect. This feature strongly suggests a water-related source for the lineae, and everyone who studies Mars is always focused on finding sources on Mars where liquid water might be found. Also, slope streaks appear more often in dunes, which also strongly suggests a dry process. One paper, however, did a comparison study of lineae with one specific kind of dune slope streak to see if the freatures might be related.

The most interesting result [pdf] for all these papers documented the apparent increase in recurring lineae following the global dust storm last year. The image at the top of that post is from this paper, and shows a fresh lineae where none had been prior to the storm. From the paper’s abstract:
» Read more

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Land of mesas

9:44 am

Ariadnes Colles
Click for full image.

Cool image time! The Mars Odyssey science team today released the image on the right, cropped and rotated to show here, of a region on Mars named “Ariadnes Colles.”

The term colles means hills or knobs. The hills appear brighter than the surrounding lowlands, likely due to relatively less dust cover.

This is certainly a place with lots of hills, or to be more precise, mesas, as many of them seem to be flat topped.

The lack of dust cover on the tops is probably because, like on Earth, the winds blow much better once you get a bit above the surface. (This is why sailing ship builders kept adding higher and higher sails to their ships, until the top sails of clipper ships rose a hundred-plus feet above the deck.) These better winds clean off the mesa tops, just as they did to the solar panels on the rovers Opportunity and Spirit several times during their long missions.

Ariadnes Colles is another example of Martian chaotic terrain. Since this region is located deep in the cratered and rough southern highlands of Mars, the erosion that created these mesas was likely not water-flows. Was it wind? Ice?

Your guess is as good as anyone’s.

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Confirmed: Ryugu is a rubble pile

2:48 pm

Close-up of Ryugu's surface
Click for source paper [pdf].

At a special session today dedicated to results from the Hayabusa-2 probe to the asteroid Ryugu at the 50th Lunar and Planetary Science Conference in Texas, scientists confirmed from numerous data and images that the asteroid has a low density, is covered with boulders and pebbles, is very porous, and is thus a rubble pile that is held together by gravity, barely.

From their lead presentation [pdf]:

The estimated total porosity is even higher than that of rubble-pile asteroid Itokawa (44 ± 4%), indicating that asteroid Ryugu is also a rubble pile. This is consistent with a theory arguing that all Solar System bodies with diameter of ~1 km should be rubble piles and might have formed from reaccumulation of fragments generated by catastrophic disruption events of ~100-km sized parent bodies.

They also posit that the asteroid’s diamond shape is caused by the asteroid’s 3.5 hour rotation, which causes its weak rubble pile structure to be easily pulled to the equator, and then outward.

Another paper [pdf] did crater counts, and found that there are fewer large craters than one would expect.

The density of large craters (D>100 m) on Ryugu is lower than the empirical saturation level and its slope is steeper than that of the saturated distribution, suggesting that craters larger than 100 m are not saturated and the size distribution reflects the crater production function. However, craters smaller than 100 m are significantly under-saturated, suggesting that some crater erasure processes such as seismic shaking and armoring effect are active on the Ryugu surface. Based on cratering chronology model for the main belt, the surface age of Ryugu is estimated to be 5–200 [million years] from the size–frequency distribution of craters larger than 100 m.

In other words, this rubble pile is constantly being shaken by its rotation and time and later impacts, which steadily rewrites the surface.

If this asteroid was headed to Earth, I imagine the only safe solution to prevent disaster would be to slowly and gently deflect it so it only flies past. To do this will require an arrival far in advance of the schedule impact, to give time for the deflection process to work.

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Snow on Mars?

1:10 pm

Snow on Mars?
Click to see full image.

At today’s presentations at the 50th Lunar and Planetary Science Conference in Texas, scientists showed images and data [pdf] suggesting that many of the Martian gullies found on cliff faces are formed when the dust layer protecting underlying snow gets blown away and the exposed snow/ice then melts.

The image on the right was taken by the high resolution camera of Mars Reconnaissance Orbiter (MRO) in 2009, and has been cropped to post here. The white streaks are what they suggest is exposed ice/snow.

From their paper [pdf]
» Read more

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Hayabusa-2 schedules explosion on Ryugu

9:49 am

The Hayabusa-2 science team has scheduled April 5 for when it will use the spacecraft to fire an explosive device into Ryugu to create a crater and debris cloud.

The probe is scheduled to detach a device loaded with explosives some 500 meters away from Ryugu. The device will set off the explosives using a timer some 40 minutes later and launch a copper “impactor” weighing about 2 kilograms into the asteroid’s surface.

The target point is several hundreds of meters away from where the space probe first touched down. The mission will require the spacecraft to move quickly to the other side of the asteroid so it won’t get hit by flying shards from the blast. A detached camera will shoot the moment of impact.

JAXA will analyze the size and shape of the crater, and how rocks fly off in a bid to collect underground samples for possible clues to the origin of the solar system.

This is different than the touchdown last month, as the spacecraft itself will not get close to the asteroid.

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A pond on Bennu

9:42 am

Pond on Bennu
Click for full resolution.

The OSIRIS-REx science team has released new high resolution images of one particular area on Bennu’s northern hemisphere. The image on the right, cropped and reduced to post here, shows what they label a “pond of regolith,” seen as the relatively smooth area in the upper left.

This is not literally a pond, but instead is a low-lying spot where smaller particles have settled over time, producing a flattish area that looks, and in some ways, resembles a pond or puddle, only in this case the material isn’t water but fine-grained dust or pebbles.

On March 19 the science team will be presenting their initial results at a special session at the 50th Lunar and Planetary Science Conference in Texas. That same day they will hold a press conference summarizing the most interesting aspects of those results. Stay tuned.

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New analysis supports catastrophic floods and intermittent ocean on Mars

7:03 pm

The intermittent ocean at the outlet to Marineris Valles

A new analysis of Martian data once again suggests that an intermittent ocean once existed in the planet’s northern hemisphere, and that it was fed by catastrophic floods coming down from the volcanoes through Marineris Valles.

“Our simulation shows that the presence of the sea would have attenuated cataclysmic floods, leading to shallow spillovers that reached the Pathfinder landing site and produced the bedforms detected by the spacecraft,” said [lead scientist Alexis Rodriguez].

The team’s results indicate that marine spillover deposits contributed to the landscape that the spacecraft detected nearly 22 years ago, and reconcile the mission’s in situ geologic observations and decades of remote-sensing outflow channel investigations.

The sea bears an uncanny resemblance to the Aral Sea on Earth in that in both instances they lack distinct shoreline terraces. Its rapid regression over shallow submerged slopes resulted in rates of shoreline front retreat too fast for the terraces to form. The same process could partly account for the long-recognized lack of northern plains shorelines.

“Our numerical simulations indicate that the sea rapidly became ice-covered and disappeared within a few thousand years due to its rapid evaporation and sublimation. During this time, however, it remained liquid below its ice cover,” said PSI Senior Scientist Bryan Travis, a co-author in the paper.

The map above shows the outlet region to the west and north of Marineris Valles. (The paper from which it is adapted is available on line here.) It shows that inland sea, created by the catastrophic floods. Because it sits at a lower elevation than the plains to the north, the floods that entered it ponded there, where they dried up. Only when the floods were at their highest did the water spill out into the northern plains.

In reading the paper, it confirms many of the suppositions I myself have made in my frequent posts analyzing numerous Mars Reconnaissance Orbiter (MRO) images, such as the lack of a clear shoreline because the ocean was short-lived. As it dried up its edge left patches of shoreline, at different elevations and in pondlike patterns, almost like the beach debris left behind by the tide.

The paper also shows that some of my guesses were not quite correct. For example, this new analysis says that the catastrophic floods only partly carved out the chaos terrain of Hydraotes Chaos, rather than do it all as I supposed here. Instead, the floods contributed, but much of the erosion occurred when the short-lived inland sea existed here, eroding away at the mesas from all sides.

Read it all. Though this remains a simulation based on what is presently very incomplete data and thus has many uncertainties, it will give you a much deeper understanding of what we presently theorize about the past geological history of Mars.

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A gathering of dust devils

9:51 am

Dust devil tracks
Click for full resolution image.

A bunch of cool images! The European Space Agency (ESA) today released more than a dozen Martian images taken by the camera on its Trace Gas Orbiter spacecraft.

In addition to a snapshot of InSight and its landing area, “The images selected include detailed views of layered deposits in the polar regions, the dynamic nature of Mars dunes, and the surface effects of converging dust devils.” The release also included images showing details of two of Mars’ giant volcanoes, Olympus Mons and Ascraeus Mons.

The image I have highlighted to the right, reduced to post here, shows a spot on Mars where for some unknown reason dust devils love to congregate.

This mysterious pattern sits on the crest of a ridge, and is thought to be the result of dust devil activity – essentially the convergence of hundreds or maybe even thousands of smaller martian tornadoes.

Below is a side-by-side comparison of this image (on the right) with a Mars Reconnaissance Orbiter (MRO) image taken in 2009 (on the left).
» Read more

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Trump’s budget will not “destroy” or “gut” science

12:10 pm

Our terrible press does it again. Yesterday the Trump administration released its proposed 2020 federal budget [pdf], and as usual the pro-government propagandists in the media got to work to lobby against it.

This proposed budget will do none of these things.

These articles all fail to apply even the slightest and tiniest bit of context to their analysis. The budget numbers proposed by the Trump administration might reduce the budgets of some science agencies from what they had gotten the year before, but overall the proposed budgets remain gigantic, far more than received by these same agencies only a few years before.

You don’t believe me? Let me open your eyes.
» Read more

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New research detects increase in Bennu’s rotation

10:32 am

New research using ground-based observations has detected a slight increase over time in the daily rotation of the asteroid Bennu.

The new research finds the asteroid’s rotation is speeding up by about 1 second per century. In other words, Bennu’s rotation period is getting shorter by about 1 second every 100 years.

While the increase in rotation might not seem like much, over a long period of time it can translate into dramatic changes in the space rock. As the asteroid spins faster and faster over millions of years, it could lose pieces of itself or blow itself apart, according to the study’s authors.

…The change in Bennu’s rotation could be due to a change in its shape. Similar to how ice skaters speed up as they pull in their arms, an asteroid could speed up as it loses material.

Nolan and his co-authors suggest the reason for the increase in Bennu’s rotation is more likely due to a phenomenon known the YORP effect. Sunlight hitting the asteroid is reflected back into space. The change in the direction of the light coming in and going out pushes on the asteroid and can cause it to spin faster or slower, depending on its shape and rotation.

Truth is, this is not a very significant finding. Asteroids don’t weight much, and thus have very weak gravitational fields. It is therefore very easy to change their orbit and rotation, as well as add or subject material from them.

In this sense, the conclusion above is likely incorrect. What they have found is that the asteroid’s rotation increased at a pace of about 1 second per century, during their study period. Their data only covers the period from 1999 to 2005. Bennu could easily slowed its rotation, or increased it even more, during other times.

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Martian massive landslides

1:24 pm

Though scientists have found some evidence of slow erosion and change on the Martian surface, it is today generally inactive. While the weak wind of Mars’ thin atmosphere continues to work its will, and the likely presence of underground frozen water acts to shift the surface shape as the seasons come and go, none of this happens quickly.

Essentially, Mars is a quiet place.

Once however catastrophic events took place, gigantic floods flowing down to the east from the planet’s huge volcanoes to carve out Marineris Valles, the solar system’s largest known canyon. As that water rushed eastward it ripped the terrain apart quickly, creating deep side canyons, drainage valleys, and chopped up regions now dubbed as chaos terrain, multiple mesas separated by numerous fissure-like canyons.

Overview of Marineris Valles and landslide

The overview map on the right shows Valles Marineris and its drainage to the east and north into the vast northern plains of Mars. It also shows the location of one of the largest regions on Mars of chaos terrain, dubbed Hydraotes Chaos, located close to the mouth of this gigantic drainage system more than 2,500 miles long.

Massive Martian landslide
Click for full image.

Recently scientists have used the high resolution camera on Mars Reconnaissance Orbiter (MRO) to begin taking images of the massive landslides on the face of the mesa north of Hydraotes Chaos that was hit directly by these floods. The location of the most immediately interesting of these landslide images is also indicated on this overview image.

To the right is that image, rotated, cropped, reduced, and annotated to post here. The white boxes indicate two full resolution sections that I highlight below at full resolution.

This image shows that full cliff. The total drop from the plateau at the top to the floor where Hydraotes Chaos is located to the south is approximately 8,200 feet, almost exactly comparable to the depth of the north rim of the Grand Canyon.

The image shows numerous evidence of avalanches and erosion, both at its base and at its rim. None of these avalanches likely occurred during those catastrophic floods, but long afterward.
» Read more

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Hayabusa-2 to get close to Ryugu again to observe next touchdown point

9:16 am

Hayabusa-2’s engineering team has decided it will on March 8 do a close approach to within 75 feet of its next planned touchdown target site in order to inspect it.

The DO-S01 operation schedule is shown in Figure 2. The spacecraft will begin descending on March 7 at 13:27 (JST, onboard time: times below are stated similarly) at a speed of 0.4m/s. The speed will then be reduced to 0.1 m/s around 23:47 on the same day. Continuing descent at this rate, we will reach our lowest altitude at around 12:22 on March 8 and then immediately begin to rise. The altitude of this lowest point will be about 23m. Please note that the times stated here are the planned values but the actual operation times may differ.

As before, they will upload navigation images as this approach is happening.

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InSight hits a rock

8:36 am

Engineers have called a pause in InSight’s drilling operation to insert a heat sensor as much as 16 feet into the Martian soil because it appears the drill has hit a large obstruction.

It penetrated to a depth between 18cm and 50cm into the Martian soil with 4,000 hammer blows over a period of four hours, explained Tilman Spohn, HP3’s principal investigator from the German space agency (DLR). “On its way into the depths, the mole seems to have hit a stone, tilted about 15 degrees and pushed it aside or passed it,” he added. “The mole then worked its way up against another stone at an advanced depth until the planned four-hour operating time of the first sequence expired.”

Prof Spohn said there would now be a break in operations of two weeks while the situation was assessed.

When these facts were first reported on March 1st, the press release did not make it clear at that time that the hammer drill was actually blocked. If it cannot drill down further, this will put a crimp in the heat sensor’s ability to measure Mars’s internal temperature. Right now it is only about a foot down, which on Earth would still have it influenced by surface temperatures.

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Possible cure for AIDS?

9:17 pm

In the past week researchers have revealed that two different patients have apparently had the AIDS HIV virus eliminated from their bodies.

The virus infects cells of the immune system, which are made in the bone marrow. A man known as the “Berlin patient” was the first person to become HIV-free after cancer treatment, back in 2007. To treat his leukaemia – a cancer of the immune system – he was given a treatment that involved killing nearly all his immune cells with radiotherapy or drugs, and then replacing them with cells from a donor. This donor was naturally resistant to HIV, thanks to a rare but natural mutation in a gene called CCR5.

Since then, no one else had had HIV eliminated from their body in the same way, until a second case was announced on Monday. This person, known as the London patient, was given bone marrow from a donor with the CCR5 mutation as a treatment for Hodgkin’s lymphoma, another immune cell cancer. He was advised to stop taking the antiviral drugs that keep the virus in check about a year afterwards. Eighteen months later, the virus hasn’t returned.

A possible third case was then announced today, at the Conference on Retroviruses and Opportunistic Infections in Seattle.

The more than dozen year gap between the first cure and the two this week is partly because it takes so long to perform the treatment and then confirm the virus is gone. Moreover, this treatment can only be given to a limited number of patients, because of the risks involved.

Nonetheless, if this cure is proven viable, it will be a great triumph for modern science.

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New method to turn CO2 into coal

1:42 pm

Scientists have developed a new relatively low-cost method for turning atmospheric carbon dioxide into solid carbon that then be used as a synthetic fuel.

“By using liquid metals as a catalyst, we’ve shown it’s possible to turn the gas back into carbon at room temperature, in a process that’s efficient and scaleable,” [Dr. Torben Daeneke, a research scientist at RMIT University.] said. The liquid metal catalyst was developed by the researchers with specific surface properties, making it extremely efficient at conducting electricity, while chemically activating the surface.

According to the press release: “The carbon dioxide is dissolved in a beaker with an electrolyte liquid and a small amount of the liquid metal, which is then charged with an electric current. The CO2 slowly converts into solid flakes of carbon, which are naturally detached from the liquid metal surface, allowing the continuous production of carbonaceous solid.”

And, yes, the process has the potential to yield a future energy source. The carbon produced may be able to be used as an electrode.

This is excellent news, for a lot of reasons. At the same time, I always find this effort to use technology to grab and convert atmospheric carbon dioxide somewhat ironic. We already have a very efficient biological tool for doing this, called plant life, which is presently thriving worldwide because of the increased CO2 in the atmosphere. The more you plant, the more oxygen you create. And what’s more, it gives you a lot more food to eat. Why do anything else?

Hat tip reader John Vernoski.

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New analysis suggests photon could make dark matter unnecessary

1:28 pm

The uncertainty of science: A new analysis by physicists that assumes a very very low mass for the photon, the particle that transmits light, could very well explain the motions of stars in galaxies and make dark matter unnecessary.

Professor Dmitri Ryutov, who recently retired from the Lawrence Livermore National Laboratory in California, USA, is an expert in plasma physics. He was awarded the American Physical Society’s (APS) 2017 Maxwell Prize for Plasma Physics for his achievements in the field. Physicists generally credit Ryutov with establishing the upper limit for the mass of the photon. As this mass, even if it is nonzero, is extremely small, it is usually ignored when analyzing atomic and nuclear processes. But even a vanishingly tiny mass of the photon could, according to the scientists’ collaborative proposal, have an effect on large-scale astrophysical phenomena.

While visiting Johannes Gutenberg University Mainz (JGU), Ryutov, his host Professor Dmitry Budker of the Helmholtz Institute Mainz (HIM), and Professor Victor Flambaum, Fellow of the Gutenberg Research College of Mainz University, decided to take a closer look at the idea. They were interested in how the infinitesimally small mass of the photon could have an effect on massive galaxies. The mechanism at the core of the physicists’ assumption is a consequence of what is known as Maxwell-Proca equations. These would allow additional centripetal forces to be generated as a result of the electromagnetic stresses in a galaxy.

Are the effects as strong as those exerted by dark matter?

“The hypothetical effect we are investigating is not the result of increased gravity,” explained Dmitry Budker. This effect may occur concurrently with the assumed influence of dark matter. It may even – under certain circumstances – completely eliminate the need to evoke dark matter as a factor when it comes to explaining rotation curves. Rotation curves express the relationship between the orbital speeds of stars in a galaxy and their radial distance from the galaxy’s center. “By assuming a certain photon mass, much smaller than the current upper limit, we can show that this mass would be sufficient to generate additional forces in a galaxy and that these forces would be roughly large enough to explain the rotation curves,” said Budker. “This conclusion is extremely exciting.” [emphasis mine]

They readily admit that this first analysis is very preliminary, and causes some additional theoretical problems that conflict with known data. Nonetheless, this simple idea could eliminate the need for the additional dark matter particle that physicists have had trouble explaining or even finding.

In fact, I am somewhat baffled why physicists had not proposed this decades ago. It provides a much more straightforward explanation for the higher rotational curves in the outer parts of galaxies, and does not require any new physics.

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New project to map shallow water sources on Mars

1:13 pm

Scientists at the Planetary Science Institute (PSI) in Arizona have begun a new project to map the near-surface ice deposits in the low elevation regions of the Martian northern hemisphere.

Two teams led by Putzig and Morgan were contracted by NASA to pursue separate mapping efforts of subsurface ice deposits in Arcadia Planitia. After their mid-term reports showed significant synergy, the teams were combined in a joint project called “Subsurface Water Ice Mapping (SWIM) on Mars,” which extends the coverage of the mapping project from an experimental swath over Arcadia Planitia to all other low elevation regions across the Martian Northern Hemisphere. “Water ice will be a critical resource for human explorers on Mars, not only for life support but also for generating fuel to power equipment on the ground and rockets for the return journey to Earth,” said Putzig, a Senior Scientist at PSI. “Maps that identify the nature and availability of potential water resources will help determine where humanity will establish its first outposts on Mars.”

The SWIM team is producing new maps of the likelihood of subsurface ice deposits over these regions by combining radar, thermal, neutron, altimetry, and image data from several Mars-orbiting spacecraft. The team is also employing newly developed techniques that include using radar returns to infer the presence of ice within the top 5 meters of the crust and applying advanced radar processing to improve resolution at depth and to estimate the purity of ice in the subsurface.

Unlike most planetary research, this project is not aimed specifically at understanding the geology of Mars. Instead, it appears focused on the needs of future human exploration and settlement, finding easily accessible water sources in the northern hemisphere of Mars. The spots they identify will likely be the first Martian real estate of significant value.

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NASA cancels overbudget instrument for Europa clipper

8:36 am

Because its budget had ballooned to three times its original estimate, NASA has decided to cancel a science instrument for its Europa Clipper probe to Jupiter’s moon.

[Thomas Zurbuchen, NASA associate administrator for science] said in the memo that, at the time of the February review, ICEMAG’s estimated cost has grown to $45.6 million, $16 million above its original cost trigger and $8.3 million above a revised cost trigger established just a month earlier. That cost was also three times above the original estimate in the ICEMAG proposal. “The level of cost growth on ICEMAG is not acceptable, and NASA considers the investigation to possess significant potential for additional cost growth,” Zurbuchen wrote in the memo. “As a result, I decided to terminate the ICEMAG investigation.”

The contrast between how NASA operates in its unmanned planetary science programs with how the agency operates in its manned programs is striking. The agency’s planetary program is probably its most successful achievement, and has been for decades. Spacecraft almost always get built close to budget, launch on time, and accomplish amazing things when their arrive at their planetary targets, either the Moon, Venus, Mars, Jupiter, Saturn, or Pluto and beyond. Part of the reason for this success is a willingness by NASA to make hard decisions, such as the one above, even if it might ruffle some political feathers. The result is that everyone focuses on getting the job done, on budget and on time. They know that if they screw up, as the ICEMAG team did here, they might find themselves on the chopping block.

In contrast, as I noted in my previous post, NASA allows things to get out of control in its manned program. In fact, they might consider this a feature of the system, not a bug. The goal is not to accomplish anything, but to funnel cash to the states and districts of elected officials. The result is that nothing ever flies, or if it does, it does so very late, very over budget, and often with technical difficulties. Worse, the focus on pleasing corrupt lawmakers like Senator Richard Shelby (R-Alabama) means that NASA is often hostile to the success in manned space by others, such as SpaceX.

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Video from Hayabusa-2’s touchdown

7:51 am

The Hayabusa-2 science team has released a video taken of the spacecraft’s quick touchdown and sample grab on the asteroid Ryugu.

I have embedded the video below the fold. It not only shows the incredible rockiness of Ryugu’s surface, with the spacecraft barely missing a large rock as it came down, it also clearly shows the resulting debris cloud and surface changes after touchdown and the firing of Hayabusa-2’s projectile into the surface to throw up material that the spacecdraft could catch. You can actually see pebbles flying about below and around the spacecraft as it quickly retreats.

The Hayabusa-2 science team plans another touchdown in the next few months, this time using a different technique to disturb the surface and grab the resulting ejecta.
» Read more

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Beresheet sends back first pictures

7:35 am

The privately-built Israeli lunar lander Beresheet has sent back its first pictures, taken on its way to the moon.

The picture, taken 37,600 km from Earth, shows the Israeli flag and the inscription with “Am Yisrael Hai” (the People of Israel Live) in Hebrew and the inscription “Small Country, Big Dreams” in English. The spacecraft was snapped as it passed over Australia, and the photograph was taken during a very slow rotation by Beresheet. The Israeli spacecraft, built in an IAI factory, is in an elliptical orbit around Earth – its greatest distance from Earth (the apogee) at this stage is some 131,000 kilometers.

While the press wants to trivialize this image by calling it a selfie, it was taken for very important engineering reasons. It demonstrates that the camera and the spacecraft’s pointing systems are working, exactly as planned.

Beresheet will continue to raise the apogee of its orbit until it enters the Moon’s gravitational sphere of influence, when it will then shift into lunar orbit.

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Hubble’s main camera down

1:36 pm

The main camera on the Hubble Space Telescope has suspended operations, and remains so as engineers troubleshoot the problem.

According to NASA, at 8:31 p.m. EST Feb. 28 (01:31 GMT March 1), 2019, the Advanced Camera for Surveys, or ACS, suspended its operations when an error was detected while the instrument was performing a routine boot procedure. “The error indicated that software inside the camera had not loaded correctly,” a statement from NASA reads. “A team of instrument system engineers, flight software experts and flight operations personnel quickly organized to download and analyze instrument diagnostic information.

They have not yet pinpointed the cause of the problem. The telescope has other cameras, however, though one of which had problems several months ago.

It is ten years since the last shuttle repair mission. That mission was expected to extend the telescope’s life for five years. Thus, the end Hubble’s life is getting closer and closer.

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Scientists confirm first exoplanet candidate found by Kepler

1:07 pm

Worlds without end: Ten years after Kepler was launched into space to find exoplanets, astronomers have finally confirmed one of the space telescopes thousands of candidates.

Despite being the very first planet candidate discovered by NASA’s Kepler Space Telescope, the object now known as Kepler-1658 b had a rocky road to confirmation. The initial estimate of the size of the planet’s host star was incorrect, so the sizes of both the star and Kepler-1658 b were vastly underestimated. It was later set aside as a false positive when the numbers didn’t quite make sense for the effects seen on its star for a body of that size. Fortuitously, Chontos’ first year graduate research project, which focused on re-analyzing Kepler host stars, happened at just the right time.

“Our new analysis, which uses stellar sound waves observed in the Kepler data to characterize the host star, demonstrated that the star is in fact three times larger than previously thought. This in turn means that the planet is three times larger, revealing that Kepler-1658 b is actually a hot Jupiter-like planet,” said Chontos. With this refined analysis, everything pointed to the object truly being a planet, but confirmation from new observations was still needed.

“We alerted Dave Latham (a senior astronomer at the Smithsonian Astrophysical Observatory, and co-author on the paper) and his team collected the necessary spectroscopic data to unambiguously show that Kepler-1658 b is a planet,” said Dan Huber, co-author and astronomer at the University of Hawaiʻi. “As one of the pioneers of exoplanet science and a key figure behind the Kepler mission, it was particularly fitting to have Dave be part of this confirmation.”

It is important to remember that until scientists obtain independent data on each of these candidates, they are not yet confirmed as exoplanets, and might only be false positives. To do this, however, is going to take a lot of work and time.

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Sunspot update February 2019: The Sun flatlines again

1:26 pm

We are now deep into solar minimum. On Sunday NOAA released its the monthly update of the solar cycle, covering sunspot activity for February 2019. As I have done every month since the start of Behind the Black, I am posting it below, annotated to give it some context.

February 2019 sunspot activity

The graph above has been modified to show the predictions of the solar science community. The green curves show the community’s two original predictions from April 2007, with half the scientists predicting a very strong maximum and half predicting a weak one. The red curve is their revised May 2009 prediction.

For the second time since the beginning of the solar minimum last year, the Sun flat-lined for an month, producing no visible sunspots during the entire month of February.

That streak has continued into March. At present we are four days into March, and still no sunspots.

The big question that I will be repeating probably every month for the next two years is whether we are merely experiencing an early and possibly deep solar minimum, or the advent of a new grand minimum, with no visible sunspots for decades. During the last grand minimum in the 1600s there is evidence the Earth cooled, so much so that it was labeled the Little Ice Age. And with previous grand minimums over the past few thousand years there is evidence that similar coolings occurred. Similarly, periods where sunspot activity was high also appear to have been periods of warmer temperatures.

Why is not clearly understood, though there is some evidence that it might be related to the increasd cosmic ray flux during solar minimum.Those rays might interact with the atmosphere to produce more clouds, thus cooling the Earth. This is not proven however and remains merely a theory linked to some tentative preliminary evidence.

If we do enter a grand minimum, scientists will likely get the answers to these questions. However, we might also find ourselves experiencing significantly colder weather. I am right now flying from Chicago to Columbus, over Lake Michigan, which is filled with ice floes, something we have not seen in March for decades. Nor has this kind of cold weather been unusual for the past decade or so. Could it be because of the weak solar maximum we just experienced and the deep and extended solar minimum just before that? No one knows.

All we can do is gather data, and find out.

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Ceres has too much water!

11:29 am

The uncertainty of science: In a paper released today, scientists puzzle over the amount of water they have detected evaporating from the dwarf planet Ceres, finding that observations by Dawn of its surface do not provide enough water sources to explain the amount of water in its thin atmosphere.

From the abstract:

The dwarf planet Ceres, the largest object in the asteroid belt, is known to contain large amounts of water ice, and water vapor was detected around it. Possible sources of the water are surface exposure of ice through impacts and subsequent sublimation when heated by sunlight, or volcanic activity. It turns out that with either process it is difficult to create sufficient water vapor to explain the observations. This means that the geological processes on Ceres are not fully understood.

They propose several possible explanations for the discrepancy. Either the measurements of evaporation are wrong, or they have not fully mapped the surface water sources on Ceres. Either or both are certainly possible, as there are great uncertainties here.

To me, the most interesting quote from their paper however is the amount of water discovered. Besides finding water on the surface at nine locations “localized on crater floors or slopes, and generally in or close to shadows,” they also found a lot of water under the surface.

The gamma ray and neutron detector on Dawn discovered a global ice‐rich layer in the subsurface of Ceres, at a depth of ~1 m in equatorial regions and much closer to the surface in polar regions. The estimated abundance of ice in this layer is ~10%. … Evidence for ice on depth scales of a few kilometers is [also] reported by Sizemore et al. (2018). From the analysis of geomorphological features, they find that the distribution of ice is heterogeneous on scales of 1 km to hundreds of kilometers.

In other words, Ceres has a lot of water below the surface, even if the evaporation rate observed by Dawn does not at present match the amount of water vapor observed surrounding Ceres.

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Curiosity sends its first images in two weeks

9:30 am

The computer problems that caused Curiosity to cease science operations two weeks ago appears to have ended with the arrival of the first new images today.

The second link above goes to the images arriving today from Curiosity’s ChemCam camera, designed to take macro images of small features on the surface. The rover also sent down a small set of thumbnail images taken by one of its navigation cameras.

It appears they have figured out why the computer did an unexpected reboot in mid-February, and are now willing to let the rover resume science operations. There is no word on what they have learned, or whether it poses a future threat to the mission, but the fact that they are downloading new data is a good sign.

I must note again that this is news you will not see anywhere else. Most news sources today will wait for the NASA press release to report on Curiosity’s recovery, while I like to do some real journalism, reporting events as they happen. Consider this another reason to donate to Behind the Black during this month’s fund-raising drive.

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Planet-wide groundwater system on Mars

9:15 am

Old news: The European Space Agency today released a press release announcing the results of a science paper that appears to have found evidence of a planet-wide groundwater system on Mars.

I call this old news because I reported on this paper a month ago here on Behind the Black: Well water likely available across Mars.

We are now near the end of my February birthday-month fund-raising drive. If anything should justify a donation or subscription, this story should provide it. You can either wait for the mainstream press to rewrite press releases, or you can support my effort to get real news to you now, reported with both enthusiasm and honest skepticism.

I really do hate to brag, but I also don’t believe in false modesty.

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ExoMars prototype test driven from 6,000 miles away

8:43 am

The engineering team that will drive ExoMars 2020 on the surface of Mars in 2021 has completed a test drive using an engineering prototype, controlling it from more than 6,000 miles away.

Experts at the European Space Agency’s centre in Oxfordshire completed a series of tests across nearly 6,900 miles (11,000 km) in order to see how the Mars rover reacts to commands across large distances.

When on the surface of Mars, the rover will need to be controlled when it is up to 250 million miles from Earth.

The trials team used a new model called ‘Charlie’ to test hardware, software and to practice science operations for the future European Space Agency (ESA) ExoMars rover, which will look for life on Mars in 2021. The Atacama desert was chosen because it is the closest we can get to a Martian-like environment.

I must admit that every press release from Europe about ExoMars 2020 gives me worried chills. Each release is often filled too much with empty boasts and little substantive detail. Worse, each seems to repeatedly remind me of some guy working in his garage on a weekend project.

The issue could merely be a case of poor press release writing, but something about each release makes these alarm bells go off in the back of my mind. With the launch only about sixteen months away, I hope I am wrong.

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Waterlike Martian lava flows

2:03 pm

Flowing like water
Click for full image.

Each month the Mars Reconnaissance Orbiter (MRO) science team highlights with captions about four out of the 300-500 new images released that month.

Of the four captioned images in February, the first was entitled “Almost Like Water,” and focused on the waterlike nature of the lava flow. The image on the right is a cropped and annotated section of that featured photograph, with the yellow arrows indicating the flow directions.

The lava appears to have flowed smoothly around obstructions, almost like water, forming streamlined islands. In the southern part of this image, a branch of the flow diverts around a small crater, and eventually rejoins the main part of the flow. [Visible in the full photograph] Irregular-shaped ring structures appear on the northern end and are related to the volcanic activity that formed the flows.

You can see an example of one of those islands near the top of the above image.

This is hardly the only MRO image showing such flows. In fact, the February image release included a bunch, some of the more intriguing of which I highlight below. These lava flows are seen in many different places on Mars, in a wide variety of geological settings, facts that suggest that volcanic activity was once very widespread and ubiquitous on Mars.
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