Tag: science

New observations of interstellar Oumuamua give it comet-like properties

11:10 am

The uncertainty of science: New observations of interstellar object Oumuamua suggest that it is a comet, not an asteroid.

[B]y combining data from the NASA/ESA Hubble Space Telescope, the Canada-France-Hawaii Telescope, ESO’s Very Large Telescope and the Gemini South Telescope, an international team of astronomers has found that the object is moving faster than predicted. The measured gain in speed is tiny and `Oumuamua is still slowing down because of the pull of the Sun — just not as fast as predicted by celestial mechanics.

The team, led by Marco Micheli (European Space Agency) explored several scenarios to explain the faster-than-predicted speed of this peculiar interstellar visitor. The most likely explanation is that `Oumuamua is venting material from its surface due to solar heating — a behaviour known as outgassing. The thrust from this ejected material is thought to provide the small but steady push that is sending `Oumuamua hurtling out of the Solar System faster than expected — as of 1 June, it is travelling with about 114 000 kilometres per hour.

Such outgassing is a typical behaviour for comets and contradicts the previous classification of `Oumuamua as an interstellar asteroid. “We think this is a tiny, weird comet,” comments Marco Micheli. “We can see in the data that its boost is getting smaller the farther away it travels from the Sun, which is typical for comets.”

If I was to speculate wildly, I could also wonder if maybe the aliens on board have decided they needed to get the heck out of here as fast as possible, and have fired their thrusters to make that happen.

5 comments

Fractured surface in Occator Crater on Ceres

10:03 am

fractures in Occator Crater

Cool image time! Dawn, now in its final very close orbit above the surface of Ceres, has released some new images. The image on the right, cropped to post here, was taken from a distance of only 22 miles, and shows a fracture network and some very pronounced cliffs on the wall of Occator Crater. The sunlight is coming from the right. You can also see a bright spot on an east-facing slope with what looks like an apron of lighter avalanche material below it. The flat smooth surface of the floor of this same canyon is likely because it is filled with dust, which has ponded there.

These fractures suggest that the wall of the crater is undergoing a slow motion avalanche, with sections separating off and slowly sagging into the crater below, creating the fractures.

Leave a comment

Grease in space

9:16 am

Based on observed data and lab recreations, astronomers have found that much of the galaxy’s interstellar dust is made of grease-like carbon molecules.

Organic matter of different kinds contains carbon, an element considered essential for life. There is though real uncertainty over its abundance, and only half the carbon expected is found between the stars in its pure form. The rest is chemically bound in two main forms, grease-like (aliphatic) and mothball-like (aromatic).

The UNSW / Ege team used a laboratory to create material with the same properties as interstellar dust. They mimicked the process by which organic molecules are synthesised in the outflows of carbon stars, by expanding a carbon-containing plasma into a vacuum at low temperature. The material was collected and then analysed by a combination of techniques. Using magnetic resonance and spectroscopy (splitting light into its constituent wavelengths) they were able to determine how strongly the material absorbed light with a certain infrared wavelength, a marker for aliphatic carbon.

“Combining our lab results with observations from astronomical observatories allows us to measure the amount of aliphatic carbon between us and the stars”, explained Professor Tim Schmidt, from the Australian Research Council Centre of Excellence in Exciton Science in the School of Chemistry at UNSW Sydney.

The researchers found that there are about 100 greasy carbon atoms for every million hydrogen atoms, accounting for between a quarter and a half of the available carbon. In the Milky Way Galaxy, this amounts to about 10 billion trillion trillion tonnes of greasy matter, or enough for 40 trillion trillion trillion packs of butter.

I guarantee that these results have a large margin of error. I also guarantee that they contain a significant element of truth.

One comment

The mysterious chaos terrain of Mars

4:05 pm

In one of my weekly posts last month (dated May 14th) delving into the May image release from Mars Reconnaissance Orbiter’s (MRO) high resolution camera, I featured an image of what planetary geologists have labeled chaos terrain, a hummocky chaotic terrain that has no real parallel on Earth but is found in many places on Mars.

This month’s image MRO release included two more fascinating images of this type of terrain. In addition, the Mars Odyssey team today also released its own image of chaos terrain, showing a small part of a region dubbed Margaritifer Chaos. Below, the Mars Odyssey image is on the right, with one of the MRO images to the left. Both have been cropped, with the MRO image also reduced in resolution. The full MRO image shows what the MRO science team labels “possibly early stage chaos” on the rim of a canyon dubbed Shalbatana Vallis.

young chaos in Shalbatana Vallis

Margaritifer Chaos

» Read more

5 comments

Ryugu from 25 miles

8:56 am

Ryugu from 25 miles

The Hayabusa-2 science team has released its first image of Ryugu, posted to the right, from a distance of only 25 miles. From the project manager:

The shape of Ryugu is now revealed. From a distance, Ryugu initially appeared round, then gradually turned into a square before becoming a beautiful shape similar to fluorite [known as the ‘firefly stone’ in Japanese]. Now, craters are visible, rocks are visible and the geographical features are seen to vary from place to place. This form of Ryugu is scientifically surprising and also poses a few engineering challenges.

First of all, the rotation axis of the asteroid is perpendicular to the orbit. This fact increases the degrees of freedom for landing and the rover decent operations. On the other hand, there is a peak in the vicinity of the equator and a number of large craters, which makes the selection of the landing points both interesting and difficult. Globally, the asteroid also has a shape like fluorite (or maybe an abacus bead?). This means we expect the direction of the gravitational force on the wide areas of the asteroid surface to not point directly down. We therefore need a detailed investigation of these properties to formulate our future operation plans.

They are going to have to spend some time in orbit to figure out not only where to land, but how to do it. More information on the mission can be found here.

Leave a comment

Trump administration to remove climate change from NOAA’s priorities

2:40 pm

According to one interpretation of a presentation by the Acting head of the Department of Commerce, the Trump administration to going to remove climate change from NOAA’s priorities.

Because of its work on climate science data collection and analysis, [NOAA] has become one of the most important American agencies for making sense of the warming planet. But that focus may shift, according to a slide presentation at a Department of Commerce meeting by Tim Gallaudet, the acting head of the agency.

In the presentation, which included descriptions of the past and present missions for the agency, the past mission listed three items, starting with “to understand and predict changes in climate, weather, oceans and coasts.” In contrast, for the present mission, the word “climate” was gone, and the first line was replaced with “to observe, understand and predict atmospheric and ocean conditions.”

The presentation also included a new emphasis: “To protect lives and property, empower the economy, and support homeland and national security.”

The job of NOAA, if it should have any job at all, should always have been to make observations and collect data. The interpretation and predictions should be left to others. By inserting the issue of climate change into its core priorities the agency’s work was almost guaranteed to become distorted and corrupted by politics. And that is exactly what we have seen.

Expect this change to cause more howls from the left. Expect even more howls when this change forces the Trump administration to start to take a close look at NOAA’s data — something they have not yet done — and discovers the amount of unjustified tampering to it, all aimed at proving the existence of global warming.

3 comments

Coldest place on Earth is even colder

12:01 pm

The uncertainty of science: Scientists have found that the coldest place on Earth in Antarctica is even colder than previously believed.

Scientists announced in 2013 they had found the lowest temperatures on Earth’s surface: Sensors on several Earth-observing satellites measured temperatures of minus 93 degrees Celsius (minus 135 degrees Fahrenheit) in several spots on the East Antarctic Plateau, a high snowy plateau in central Antarctica that encompasses the South Pole. But the researchers revised that initial study with new data and found the temperatures actually reach minus 98 degrees Celsius (minus 144 degrees Fahrenheit) during the southern polar night, mostly during July and August.

When the researchers first announced they had found the coldest temperatures on Earth five years ago, they determined that persistent clear skies and light winds are required for temperatures to dip this low. But the new study adds a twist to the story: Not only are clear skies necessary, but the air must also be extremely dry, because water vapor traps some heat in the air.

They say this is about as cold as it is possible on the Earth’s surface, as it presently exists.

2 comments

Hawaii’s Supreme Court to review TMT’s permit, again

8:36 am

Hawaii’s Supreme Court is set to review, for the second time, the construction permit for the Thirty Meter Telescope.

Much of the arguments centered around whether it was a conflict of interest for a hearings officer who made a key recommendation in favor of the project to be a member of a Hawaii astronomy center. The state allowed retired judge Riki May Amano to preside over contested-case hearings for the contentious project despite complaints from telescope opponents who decried her paid membership to the Imiloa Astronomy Center.

The Big Island center is connected to the University of Hawaii, which is the permit applicant.

Opponents appealed to the Supreme Court after Amano recommended granting the permit and the state land board approved it. “She should have never presided over the case,” Richard Wurdeman, an attorney representing telescope opponents, told the justices. He noted the center included exhibits about the project planned for the Big Island’s Mauna Kea, Hawaii’s tallest mountain.

The details don’t really matter. Nor will the decision. The protesters will simply find another petty issue if they lose, and will appeal again. Their goal, apparently supported covertly by Hawaii’s Democratic government, is to delay, delay, and delay, until the consortium building TMT is forced to abandon Hawaii.

One comment

European satellite designed to test space junk removal released from ISS

9:40 am

Europe’s RemoveDEBRIS satellite was released from ISS yesterday in preparation for its testing a variety of technologies for removing and deorbiting space junk.

The article at the link does a terrible job trying to describe this mission. Better to return to a news story from 2016, when Europe first announced this project. The video from that story, embedded below the fold, does an excellent job detailing the four experiments, which are mostly aimed at testing technologies that could be added to satellites that would make either their capture or deorbit easier.

Maybe the most interesting aspect of this mission however is how it got into space. It was launched as part of a SpaceX Dragon cargo mission. It was deployed by NanoRacks, using its privately developed deployment system attached to Japan’s Kibo module.

Launch from ISS means that the satellite’s deployment and orbit were far more controllable than if it had been launched directly into space as a secondary payload during a rocket launch. NanoRacks is selling this approach commercially, and this satellite is the largest deployed by them to date.
» Read more

4 comments

Martian dust storm goes global

12:51 pm

Data from orbit and from Curiosity at Gale Crater confirms that the dust storm that has shut down Opportunity is now a global storm, encircling Mars.

The Martian dust storm has grown in size and is now officially a “planet-encircling” (or “global”) dust event.

Though Curiosity is on the other side of Mars from Opportunity, dust has steadily increased over it, more than doubling over the weekend. The sunlight-blocking haze, called “tau,” is now above 8.0 at Gale Crater — the highest tau the mission has ever recorded. Tau was last measured near 11 over Opportunity, thick enough that accurate measurements are no longer possible for Mars’ oldest active rover.

This will be first global storm to occur on Mars since Curiosity landed in 2012, thus giving scientists the best opportunity to study such an event.

Meanwhile, Opportunity remains silent. This does not mean it is dead, but that it doesn’t have enough sunlight to charge its batteries. It might die during this storm if the storm lasts long enough, but we won’t know one way or the other until the storm finally eases.

8 comments

Ryugu seen from 150-200 miles

8:41 am

Ryugu from 150 milesl

Cool image time! Hayabusa-2’s approach to asteroid Ryugu continues. The image to the right, cropped to post here, shows one of four images taken by the spacecraft on June 17 and June 18. In this image the distance is about 150 miles. As noted in the Hayabusa-2 press release,

The shape of the asteroid looks like a spinning top (called a “Coma” in Japanese), with the equatorial part wider than the poles. This form is seen in many small asteroids that are rotating at high speed. Observed by radar from the ground, asteroid Bennu (the destination of the US mission, OSIRIS-REx), asteroid Didymous (the target of the US DART project), and asteroid 2008 EV5 that is approaching the Earth, all have a similar shape.

On the surface of asteroid Ryugu, you can see a number of crater-like round recessed landforms. In the first image, one large example can be seen with a diameter exceeding 200m. This moves to the left and darkens as the asteroid rotates and the lower part becomes cast in shadows.

The bulge at the equator forms a ridge around the asteroid like a mountain range. Outside this, the surface topology appears very ridge-shaped and rock-like bulges are also seen. These details should become clearer as the resolution increases in the future.

Based on the visible landforms, they presently estimate Ryugu’s rotation period to be about 7.5 hours.

One comment

The epic lava flows of Olympus Mons

12:10 pm

Lava flows off of Olympus Mons

The eruption of Kilauea volcano in Hawaii has garnered a lot of deserved press coverage, having added at least a 200 acres of new land and destroyed at least 700 homes. Similarly, the recent violent eruption of a volcano in Guatemala, killing 100 people in its wake, has also gotten much deserved news coverage.

The magnitude of both however would pale in comparison to the stupendous eruption that occurred several hundred million years ago at the solar system’s largest volcano, Olympus Mons on Mars. While Kilauea is about 100 miles across, Olympus Mons is about 370 miles wide, and is so large that because of the curvature of Mar’s surface it is literally impossible for a viewer on the ground to actually see the volcano, in its entirety.

Both volcanoes are shield volcanoes, however, which means the lava flows don’t necessarily come from the caldera, but often from vents on the volcano’s slopes. Eruptions might be violent, but they generally do not involve the powerful explosive force of the sudden eruption, as seen in Guatemala and at Mount St. Helens in 1980 in the U.S. Instead, the lava seeps out steadily and continuously, an unstoppable flow that steadily overwhelms the surrounding terrain.

Olympus Mons

The flows that created Olympus Mons however were an epic event probably lasting millions of years, which brings us to this post. In the June release of Mars Reconnaissance Orbiter high resolution images, I found the image above, cropped and reduced in resolution to post here. It shows lava flowing down off one of the many escarpments on the slopes of Olympus Mons. This is not at the edge of the volcano’s shield, but just inside it. The map at the right, created using the archive of MRO’s high resolution camera, indicates the location of this flow, shown by the left light blue rectangle on the southeast slope of the volcano’s shield. The red rectangles show all the other images MRO has taken of Olympus Mons.

The scale of the MRO image above gives an indication of how big that eruption at Olympus Mons was.
» Read more

2 comments

Curiosity on the march

8:50 am

It appears that, after a descent down off of Vera Rubin Ridge and then spending 30 sols sitting at one spot to do its first drilling in more than a year, Curiosity is about to resume travel up Mount Sharp.

With its newly resurrected drilling capabilities, Curiosity will do one last pass over the Vera Rubin Ridge units, now that the rest of the instrument suite onboard can have access to this and future drill samples.

It appears they will be returning to their planned route, across the ridge and down off it to head up towards one known recurring black streak that might be a seep of underground water.

They have not provided any details about the lab results from the drill sample, but that isn’t surprising. It will take some time to analyze it, and the scientists involved will want the glory of publishing their results once that analysis is complete. What is clear from the update is that the drilling worked, and that this particular drillhole is likely to produce some of the more significant findings from Curiosity.

Leave a comment

The modern non-debate over climate, or anything

11:28 am

Last week there was a much bally-hooed public event where several very well known scientists from both sides of the global-warming debate were given an opportunity to make their case before the public. Though they were not the only speakers, the two names that were of the most interest were Michael Mann (global warming advocate) and Judith Curry (global warming skeptic).

Mann’s appearance was especially intriguing, because he has very carefully insulated himself from any unpredictable public questioning in the decade since the climategate emails were released (revealing that his objectivity and rigor as a scientist could be considered very questionable). With Curry as an opposing panelist it seemed to me that this event could produce some interesting fireworks.

The event was in West Virginia, too far away for me to attend. However, one of my caving buddies from back when I lived in DC and caved monthly in West Virginia, John Harman, lives in West Virginia and as the owner of a company that builds space-related equipment I knew he’d be interested. I let him know about the event, and he decided to make the two and a half hour drive to watch.

Below is John’s detailed report on the event. You can see Judith Curry’s full presentation and script here.

I only have one comment, indicated by my headline above. The way this event was staged was specifically designed to prevent a real debate. There was no vibrant give and take between participants. Instead, the speakers were each given time to make their presentation, and then were faced with what appeared to be preplanned questions. Very staged. When Curry was given a question she didn’t expect, she said so, and was surprised.

This is not how real science is done. Michael Mann strongly pushes the theory that the increase in carbon dioxide in the atmosphere, caused by human-activity, is warming the climate. His work has been strongly challenged by qualified scientists like Judith Curry. For science, and the truth, to prosper, Mann has to be willing to face those challenges directly, and address them. Instead, this event as well as every other public forum that Mann has participated in for the past decade have all been designed to protect him from those challenges. Nor has Mann been the only global warming enthusiast protected in this way.

The result is a decline in intellectual rigor and the rise of politics and propaganda within the climate science community, as noted by Curry in her last slide. She calls this “The Madhouse effect”:

The madhouse is characterized by

  • Rampant overconfidence in an overly simplistic theory of climate change
  • Enforcement of a politically-motivated, manufactured ‘consensus’
  • Attempts to stifle scientific and policy debates
  • Activism and advocacy for their preferred politics and policy
  • Self-promotion and ‘cashing in’
  • Public attacks on other scientists that do not support the ‘consensus’

Curry notes that she was forced out of academia expressly because of these factors, merely because she expressed skepticism concerning the hypothesis of human-caused global warming.

The worst part of this lack of debate is that it now permeates our society. In every area of importance to our nation’s future, debate is now impossible. The left, to which global warming activists like Michael Mann routinely belong, will not tolerate it, and will do anything to avoid it, even so far as to destroy the careers of anyone who dares challenge them. This is what Mann advocated in the climategate emails, and this is exactly what happened to Judith Curry.

Anyway, take a look at John’s very fair-minded report of the event. You will find it quite edifying.
» Read more

20 comments

Questions raised about NEOWISE asteroid data analysis

10:05 am

A computer entrepreneur has raised questions about the data analysis used by the scientists in charge of NASA’s NEOWISE space telescope (formerly called the Wide-field Infrared Space Telescope, or WISE).

Myhrvold, a former chief technologist for Microsoft, founded the patent-buying firm Intellectual Ventures in Bellevue, Washington, in 2000; on the side, he pursues interests ranging from modernist cuisine to palaeontology. A few years ago, he began exploring ways to detect dangerous space rocks. He soon argued3 that the Large Synoptic Survey Telescope, a ground-based telescope being built in Chile, would have the capacity to find nearly all the same asteroids as NASA’s proposed successor to NEOWISE, called NEOCam.

That turned his attention to how asteroids could be studied in space, and to the NEOWISE data. “I thought, this will be great, maybe we’ll be able to find some new and interesting things in here,” he says. But Myhrvold soon became frustrated with the quality and analysis of the data. He posted a critical preprint on arXiv in May 2016, and the peer-review game was on.

His first peer-reviewed critique was published in Icarus in March4. In it, he explored the mathematics of how asteroids radiate heat, and said that the NEOWISE team should have accounted for such effects more thoroughly in its work.

The latest paper1 holds the bulk of the NEOWISE critique. Among other things, Myhrvold argues that the NEOWISE team applied many different modelling techniques to many different combinations of data to achieve its final results. He also criticizes the choice to include previously published data on the diameter of certain asteroids in the data set, rather than using NEOWISE measurements — which, though less precise, are at least consistent with the rest of the database. Such choices undermine the statistical rigour of the database, he says.

Alan Harris, a planetary scientist with the consulting firm MoreData! in La Cañada Flintridge, California, was one of the paper’s reviewers. “In my opinion, it has important things to say,” he says. “It is my hope that the scientific community will read the paper and pay attention to the analysis Myhrvold has presented, as he has raised a number of significant issues.”

The disagreement involves the NEOWISE team’s estimate of asteroid sizes, based on the infrared data. Myhrvoid questions their estimates.

More details about the clashes between Myhrvoid and the NEOWISE science team over the past two years can be found here. The NASA scientists do not come off well. They appear to be very defensive, acting to stonewall any review of their work. Repeatedly they attempted to defy Myhrvoid’s FOIA requests (only made when they refused to release their raw data), including redacting significant information for no justifiable reason.

I have really only one question: Does the behavior of these NASA planetary scientists sound familiar? To me it does, and what it reminds me of speaks very badly for the science being done in the NEOWISE mission at NASA.

7 comments

Landslides on Ceres

9:31 am

Landslides on rim of Occator Crater

Cool image time! With Dawn completing its descent into its final low orbit only about 30 miles above the surface of Ceres, it is beginning to take some very spectacular images. Above is a cropped section from a full image taken on June 9th of the rim of Occator Crater from an altitude of 27 miles. It shows evidence of landslides on the crater’s rim, as well as at least two bright patches. If you click on it you can see the entire picture.

Crater on Ceres

Nor is this the only cool image released As Dawn descended to its new orbit, it took one very cool oblique image of the planet’s horizon. On the right I have cropped a small section out of one such image, taken on May 30th from an altitude of 280 miles. If you click on it you can see the full image, showing numerous other small craters all around it, to the horizon.

Note the bright streaks on the crater walls, suggestive of more landslides as well as seepage of the thought-to-exist brine from below the surface.

For the next year or so, as Dawn winds down its mission, expect a lot more very intriguing pictures of Ceres. I am especially eager to see close-ups of the bright spots at the center of Occator Crater.

Leave a comment

New analysis suggests Ceres has more organic molecules than previously estimated

12:11 pm

The uncertainty of science: A new analysis of data from Dawn now suggests that the surface of Ceres has a greater percentage of organic molecules than previously estimated.

To get an initial idea of how abundant those compounds might be, the original research team compared the VIR data from Ceres with laboratory reflectance spectra of organic material formed on Earth. Based on that standard, the researchers concluded that between six and 10 percent of the spectral signature they detected on Ceres could be explained by organic matter.

But for this new research, Kaplan and her colleagues wanted to re-examine those data using a different standard. Instead of relying on Earth rocks to interpret the data, the team turned to an extraterrestrial source: meteorites. Some meteorites — chunks of carbonaceous chondrite that have fallen to Earth after being ejected from primitive asteroids — have been shown to contain organic material that’s slightly different from what’s commonly found on our own planet. And Kaplan’s work shows that the spectral reflectance of the extraterrestrial organics is distinct from that of terrestrial counterparts.

“What we find is that if we model the Ceres data using extraterrestrial organics, which may be a more appropriate analog than those found on Earth, then we need a lot more organic matter on Ceres to explain the strength of the spectral absorption that we see there,” Kaplan said. “We estimate that as much as 40 to 50 percent of the spectral signal we see on Ceres is explained by organics. That’s a huge difference compared to the six to 10 percent previously reported based on terrestrial organic compounds.”

Please note: Both estimates depend on assumptions that could easily be wrong. Ceres might have less organics, or more, than either estimate. Or somewhere in the middle. These estimates are merely educated guesses.

And remember, organic molecules does not mean life. It only means the molecules use carbon as a component.

Leave a comment

Contact with Opportunity lost

9:33 am

The Opportunity science team has lost contact with Opportunity as it automatically shuts down operations to survive low battery power due to the dust storm.

This does not necessarily mean the rover is dead. Depending on how long this period of low power lasts, the rover could return to life once the dust storm passes. Or not. We can only wait and see.

A press conference today on the dust storm and Opportunity’s status begins at 1:30 Eastern time today.

8 comments

The two candidate landing sites for ExoMars2020

12:27 pm

The June release of new images from Mars Reconnaissance Orbiter (MRO) included three images of the two candidate landing sites for Europe’s 2020 ExoMars rover mission. All three images provide us as hint at what that rover might see when it arrives a few years from now.

ExoMars 2020 landing sites

The two candidate sites are locations on Mars dubbed Mawrth Vallis and Oxia Palas. The map to the right shows their general location to the east of Mars’s giant volcanoes and giant canyon Valles Marineris. The red splotches indicate the large number of images taken by MRO of these locations, partly to help the ExoMars science team choose which site to pick and partly to study the geology in these Martian locations. As you can see, both candidate sites are in the transition zone between the northern low plains and the southern highlands.

At first glance Mawrth Vallis seems the more spectacular site. Mawrth (Welsh for Mars) is one of the gigantic drainage canyons near Valles Marineris. Though tiny in comparison to Valles Marineris, on Earth it would easily rival the Grand Canyon in size, and in fact is slightly longer (400 miles versus 300 miles). Unlike the Grand Canyon, however, Mawrth Vallis doesn’t appear to have a distinct or obvious rim. This video, produced by the European Space Agency using images from its Mars Express orbiter, gives a sense of the canyon’s terrain as it flies upstream from the northern lowlands to the canyon’s high point in the southern highlands. The highlands on either side of the canyon more resemble the broken geology of Mars’s chaos regions that are found scattered about in this transition zone than the flat generally level Kaibab plateau that surrounds the Grand Canyon.

Mawrth Vallis

The image on the right is a tiny crop from the most recently released MRO image. The full image shows a strip of the upper plateau south of canyon and near its inlet from the southern highlands. This crop reveals a surface that is a wild mixture of colors and complex geology. In fact, in a 2017 MRO image release showing a different place in Mawrth Vallis, the canyon was dubbed a “painted desert.” To quote that release:

The clay-rich terrain surrounding Mawrth Vallis is one of the most scenic regions of Mars, a future interplanetary park. …The origin of these altered layers is the subject of continued debates, perhaps to be resolved by a future rover on the surface. We do know that these layers are very ancient, dating back to a time when the environment of Mars was wetter and more habitable, if there were any inhabitants.

Other MRO images of Mawrth Vallis here and here emphasize this description.

As for Oxia Palas, the other candidate landing site for ExoMars 2020, in the June MRO image release there were two images.
» Read more

Leave a comment

The mysterious dust surrounding Tabby’s Star

8:44 am

New studies of Tabby’s Star suggest that the dust clouds that cause it to fluctuate in brightness in apparently random ways are unusual and baffling in their own right.

[I]t appears that the dimming of Tabby’s star comes not from large objects such as swarms of asteroids, comets, or alien solar collectors, but from drifting bands of dust particles. But like any good mystery, it’s not quite that simple.

Each of the four dimming events observed in 2017 affected red and blue light differently, suggesting that they involved dust particles of different sizes. And the long-term brightness changes appear to be associated with much larger grains. “So the dust cloud is extremely complex,” Bodman says. “Each dip is a different kind of dust … What we’re seeing is different parts of the [dust] cloud as they pass in front of the star.”

A first guess, probably wrong, is that the four dimming events were caused by dust streams orbiting the star at different distances, each a different patchy ring around the star made up of slightly different materials.

And if you accept my guess as right, I also have bridge in Brooklyn I want to sell you. Real cheap too!

Leave a comment

China cracks down on corrupt science

8:38 am

The Chinese government has instituted new policies aimed at shutting down corrupt practices in journal peer review and funding that have previously encouraged scientific misconduct.

The country’s most powerful bodies, the Chinese Communist Party and the State Council, introduced a raft of reforms on 30 May aimed at improving integrity across the research spectrum, from funding and job applications to peer-review and publications.

Under the new policy, the Ministry of Science and Technology (MOST) will be responsible for managing investigations and ruling on cases of scientific misconduct, a role previously performed by individual institutions. And for the first time, misconduct cases will be logged in a national database that is currently being designed by MOST.

Inclusion in the list could disqualify researchers from future funding or research positions, and might also affect their ability to get jobs outside academia. The Chinese Academy of Social Sciences will oversee the same process for social scientists. The policy also states that MOST will establish a blacklist of ‘poor quality’ scientific journals, including domestic and international titles. Scientists who publish in these journals will receive a warning, and those papers will not be considered in assessments for promotions, jobs and grants. A couple of such blacklists already exist, but rarely are they run formally by a government agency.

In recent years China has been the source of many examples of blatant scientific misconduct, from faking data in papers to getting them peer reviewed by non-existent reviewers. This policy change is aimed at stopping this misconduct, and is likely happening because much of China’s leadership comes from its space industry, which requires honesty in its work or the rockets will crash.

At the same time, the policy gives the government great power over all scientific work, and we all know what happens eventually when you give the government great power. While the goals here are laudable, and will likely in the near future produce positive results, the long term consequences will likely end up stifling independent research.

Leave a comment

More Earthlike exoplanets!

9:13 am

Astronomers using data from Kepler have discovered two stars, both with multiple orbiting Earth-sized planets. One has three planets all almost exactly the mass of Earth.

The first exoplanetary system is located in the star K2-239, characterized by these researchers as a red dwarf type M3V from observations made with the Gran Telescopio Canarias (GTC), at the Roque de los Muchachos Observatory (Garafía, La Palma). It is located in the constellation of the Sextant at 50 parsecs from the Sun (at about 160 light years). It has a compact system of at least three rocky planets of similar size to the Earth (1.1, 1.0 and 1.1 Earth radii) that orbit the star every 5.2, 7.8 and 10.1 days, respectively.

The other red dwarf star called K2-240 has two super-Earth-like planets about twice the size of our planet. Although the atmospheric temperature of red dwarf stars, around which these planets revolve, is 3,450 and 3,800 K respectively, almost half the temperature of our Sun, these researchers estimate that all planets discovered will have temperatures superficial tens of degrees higher than those of the planet Earth due to the strong radiation they receive in these close orbits to their stars.

Knowing more about the surface environments of these very Earthlike exoplanets, as hostile as they might be to life, would teach us a great deal about our own planet and its birth and evolution.

5 comments

Curiosity finds methane fluctuates seasonally in Gale Crater

9:05 am

Seasonal methane on Mars

In its second significant science release yesterday (the first relating to the discovery of organics), the Curiosity science team revealed that they have found over almost three Martian years the amount of methane in the atmosphere appears to fluctuate seasonally. The graph on the right illustrates this change.

[The data] show methane rises from just above 0.2ppb in the northern hemisphere winter to a fraction over 0.6ppb in the summer. The team’s best explanation is that methane is seeping up from underground, perhaps from stored ices, and is then being released when surface soils are warmed.

The team cannot positively identify the origin of the methane, but the researchers think they can close down one particular mechanism for its production. This involves sunlight breaking up carbon-rich (organic) molecules that have fallen to the planet’s surface in meteorites.

The variation in ultraviolet light over the course of the seasons is not big enough to drive the scale of the change seen in the methane concentration, says Dr Webster. “We know the intensity of the Sun and this mechanism should produce only a 20% increase in methane during the summer, but we’re seeing it increase by a factor of three,” he explained.

The change could be caused by either a chemical or a biological process. At this time there is no way to determine which.

18 comments

Germany to do partial gravity experiments using Zero-G airplane

8:53 am

In what might be the first human experiments in partial gravity, Germany has hired the Zero-G airplane for a series of flights testing how humans react in such conditions.

In the Partial G Campaign, the pilots fly three special parabolic shapes. So instead of zero-g or microgravity, one quarter, half and three quarters of Earth’s gravity will still be present. Passengers on board will therefore experience one quarter, half or three quarters of their own body weight – depending on the trajectory,” explains Stang.

The goal of these flights is to see what effect partial gravity has on human muscle control.

For humans to be able to move around and interact with their environment, they require finely tuned muscle movements, to walk around or ensure a secure footing, for instance. Under partial gravity, in particular, they must be able to effectively control their muscles via their neural pathways. If we are unable to do so, the risk of stumbling is dramatically increased. This applies to both humans on Earth and astronauts in space. However, partial gravity conditions appear to influence this neuromuscular control in challenging situations, increasing the astronaut’s risk of stumbling. Researchers at the University of Freiburg are investigating why this is so. The results are intended to reduce the risk to astronaut safety during missions to other planets, thereby resolving a fundamental safety issue in human physiological space exploration.

This is better than nothing, but it seems to me to be the least important thing to study in partial gravity. The Apollo astronauts clearly demonstrated that humans can adapt their muscle movements to partial gravity. What we must instead learn is whether partial gravity will eliminate bone loss, loss of cardio-vascular conditioning, spinal changes, balance problems, and the vision damage, all of which have been found to occur in weighlessness.

At the same time, it is probably impossible to study any of these latter issues during a short parabolic vomit comet flight. The Germans are doing what they can. Unfortunately, they might be the only ones doing anything in this area.

One comment

How an accelerometer works

6:01 pm

An evening pause: A little dense for non-engineers, but just clear enough to be educational for all.

Hat tip Edward Thelen.

As always, I am in need of suggestions for evening pauses. If you’ve seen something you think will fit, place a comment here, in this post, but don’t post a link to your suggestions. I will contact you so that you can send it to me direct and I can then schedule it.

Leave a comment

Curiosity finds evidence of complex carbon molecules

11:40 am

In a study released today, the Curiosity science team announced that earlier drill samples revealed evidence of complex organic carbon molecules, the possible remains of past life.

To unlock organic molecules from the samples, the oven baked them to temperatures of between 600°C and 860°C—the range where a known contaminant disappeared—and fed the resulting fumes to a mass spectrometer, which can identify molecules by weight. The team picked up a welter of closely related organic signals reflecting dozens or hundreds of types of small carbon molecules, probably short rings and strands called aromatics and aliphatics, respectively. Only a few of the organic molecules, sulfur-bearing carbon rings called thiophenes, were abundant enough to be detected directly, Eigenbrode says.

The mass patterns looked like those generated on Earth by kerogen, a goopy fossil fuel building block that is found in rocks such as oil shale—a result the team tested by baking and breaking organic molecules in identical instruments on Earth, at Goddard. Kerogen is sometimes found with sulfur, which helps preserve it across billions of years; the Curiosity scientists think the sulfur compounds in their samples also explain the longevity of the Mars compounds.

Earth’s kerogen was formed when geologic forces compressed the ancient remains of algae and similar critters. It’s impossible to say whether ancient life explains the martian organics, however. Carbon-rich meteorites contain kerogenlike compounds, and constantly rain down on Mars. Or reactions driven by Mars’s ancient volcanoes could have formed the compounds from primordial carbon dioxide. Monica Grady, a planetary scientist at The Open University in Milton Keynes, U.K., believes the compounds somehow formed on Mars because she thinks it’s highly unlikely that the rover dug into a site where an ancient meteorite fell. She also notes that the signal was found at the base of an ancient lake, a potential catchment for life’s remains. “I suspect it’s geological. I hope it’s biological,” she says.

It must be emphasized once again that they have not found evidence of past life. What they have found are the types of molecules that are often left behind by life, but can also form without the presence of life.

This result, from past drillholes in the Murray Formation, explains however why Curiosity headed back downhill to do its most recent drill test.

Curiosity has one last tool to help the team find out: nine small cups containing a solvent that frees organic compounds bonded in rock, eliminating the need to break them apart—and potentially destroy them—at high temperatures. In December 2016, rover scientists were finally prepared to use one of the cups, but just then the mechanism to extend the rover’s drill stopped working reliably. The rover began exploring an iron-rich ridge, leaving the mudstone behind. In April, after engineers found a way to fix the drill problem, the team made the rare call to go backward, driving back down the ridge to the mudstone to drill its first sample in a year and half. If the oven and mass spectrometer reveal signs of organics in the sample, the team is likely to use a cup. “It’s getting so close I can taste it,” says Ashwin Vasavada, Curiosity’s project scientist at the Jet Propulsion Laboratory in Pasadena, California.

The newest drillhole sample has now entered the mass spectrometer. Stay tuned!

4 comments

Movie of Juno’s thirteenth fly-by of Jupiter

10:12 am

Cool image time. Mathematician and software programmer Gerald Eichstädt has released another movie using images from Juno’s thirteenth close fly-by of Jupiter.

I have embedded the movie below the fold. As he notes,

The movie covers two hours of this flyby in 125-fold time lapse, the time from 2018-05-24T04:41:00.000 to 2018-05-24T06:41:00.000. It is based on 27 of the JunoCam images taken during the flyby, and on spacecraft trajectory data provided via SPICE kernel files.

The view begins by looking down at the northern hemisphere, and gets to within 2,200 miles of the giant planet’s cloud tops.

» Read more

3 comments
1 … 129 130 131 132 133 … 279