Tag: science

The floating mountains of Pluto

9:09 am

Pluto's floating mountains

The New Horizons science team has released a new image of Pluto’s smooth heart-shaped area, dubbed Sputnik Planum, focusing this time on the mountains of water ice that pop up through the plain and are apparently floating on the nitrogen sea, having broken off from the shoreline.

Because water ice is less dense than nitrogen-dominated ice, scientists believe these water ice hills are floating in a sea of frozen nitrogen and move over time like icebergs in Earth’s Arctic Ocean. The hills are likely fragments of the rugged uplands that have broken away and are being carried by the nitrogen glaciers into Sputnik Planum. ‘Chains’ of the drifting hills are formed along the flow paths of the glaciers. When the hills enter the cellular terrain of central Sputnik Planum, they become subject to the convective motions of the nitrogen ice, and are pushed to the edges of the cells, where the hills cluster in groups reaching up to 12 miles (20 kilometers) across.

I have significantly cropped the image to show it here. Be sure and check out the full version, because there is a wealth of fascinating details in it.

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China releases images from lunar rover and lander

10:33 am

Yutu on the Moon

China has made available a new batch of very cool images taken by its Chang’e 3 lander and Yutu rover, and Emily Lakdawalla at the Planetary Society has figured out how to view them.

In a recent guest blog post, Quanzhi Ye pointed to the Chinese version of the Planetary Data System, and shared the great news that Chang’e 3 lander data are now public. The website is a little bit difficult to use, but last week I managed to download all of the data from two of the cameras — a total of 35 Gigabytes of data! — and I’ve spent the subsequent week figuring out what’s there and how to handle it.

So, space fans, without further ado, here, for the first time in a format easily accessible to the public, are hundreds and hundreds of science-quality images from the Chang’e 3 lander and Yutu rover. I don’t usually host entire data sets (PDS-formatted and all) but I made an exception in this case because the Chinese website is a bit challenging to use.

The image above is a cropped version of Yutu, taken by the lander. Be sure and go to the link to see the full image as well as others.

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A look inside Comet 67P/C-G

9:53 am

The Rosetta science team has determined that Comet 67P/C-G has no voids or large caverns in its interior, and that its low density is because its dust and water ice have mixed to produce a “fluffy” density.

In a new study, published in this week’s issue of the journal Nature, a team led by Martin Pätzold, from Rheinische Institut für Umweltforschung an der Universität zu Köln, Germany, have shown that Comet 67P/Churyumov-Gerasimenko is also a low-density object, but they have also been able to rule out a cavernous interior. This result is consistent with earlier results from Rosetta’s CONSERT radar experiment showing that the double-lobed comet’s ‘head’ is fairly homogenous on spatial scales of a few tens of metres.

The most reasonable explanation then is that the comet’s porosity must be an intrinsic property of dust particles mixed with the ice that make up the interior. In fact, earlier spacecraft measurements had shown that comet dust is typically not a compacted solid, but rather a ‘fluffy’ aggregate, giving the dust particles high porosity and low density, and Rosetta’s COSIMA and GIADA instruments have shown that the same kinds of dust grains are also found at 67P/Churyumov-Gerasimenko.

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The candidates’ take on science

9:30 am

The journal Science today posted this somewhat useful review of the positions that the presidential candidates have taken on a variety of science issues.

One must read this article while recognizing that Science is not trustworthy on many of these subjects. For one, its position is always for more funding. If a politician even suggests that the rate of budget increases should be trimmed, Science will frame that suggestion as if the politician wants to slash all spending for science.

For another, Science is quite biased and agenda-driven when it comes to climate change, and illustrates that bias in this article in its reporting on Ted Cruz (R-Texas) and his position on this subject. To quote:

Cruz has used his position as head of a Senate subcommittee that oversees climate research to question recent temperature trends. Last fall Cruz called climate change a “religion.” Voted no on a measure affirming that humans contribute to climate change. [emphasis mine]

The highlighted words above is a misstatement of what Cruz has said and serves to trivialize his position. He hasn’t questioned the “temperature trends”, which for almost two decades have been stalled. If anything, he has noted these trends as evidence that the theory of human-caused global warming has a problem. What he has questioned is the data that NOAA and NASA have been publishing. If anything, Cruz’s positions on the science of climate change have indicated that he has educated himself well on the subject, and has taken some thoughtful positions on it.

Nonetheless, this article is worth reviewing, as it reveals a great deal about the candidates. A close look for example at Rubio’s position on climate change reveals that he might not be consistent, and that his stated positions now might not match what he does should he become president.

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An issue with Curiosity’s scoop

10:35 pm

The unit at the end of Curiosity’s robot arm that scoops up sand and processes it through sieves experienced “an anomaly” on January 25, causing a halt in arm operations.

The instrument has been scooping up sand from the sand dune that the rover has been studying recently. So far there has been no details at all about the “anomaly”, so it is unclear how serious the problem is. In the meantime the rover has been using its cameras and other instruments to do other observations.

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Water ice on Pluto’s surface

1:33 pm

The uncertainty of science: An analysis of data from New Horizons suggests that water ice is more widespread on Pluto’s surface than previously believed.

The new map shows exposed water ice to be considerably more widespread across Pluto’s surface than was previously known — an important discovery. But despite its much greater sensitivity, the map still shows little or no water ice in the informally named places called Sputnik Planum (the left or western region of Pluto’s “heart”) and Lowell Regio (far north on the encounter hemisphere). This indicates that at least in these regions, Pluto’s icy bedrock is well hidden beneath a thick blanket of other ices such as methane, nitrogen and carbon monoxide.

As the press release notes, water ice is actually “Pluto’s crustal ‘bedrock'”, so there really is plenty there. It is just buried below a surface of methane, nitrogen, and carbon monoxide “topsoil”.

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300 climate scientists demand NOAA explain its global warming climate data

9:32 am

No settled science here: Three hundred climate scientists have signed a letter demanding that NOAA stop stonewalling the Congressioinal investigation of the agency’s repeated adjustments to raw climate data so that the record shows increased warming, when there is none.

Of the 300 letter signers, 150 had doctorates in a related field. Signers also included: 25 climate or atmospheric scientists, 23 geologists, 18 meteorologists, 51 engineers, 74 physicists, 20 chemists and 12 economists. Additionally, one signer was a Nobel Prize winning physicist and two were astronauts.

Seems to me that this letter and the number of climate scientists willing to sign it alone demonstrates that the “97 percent consensus” on global warming is bogus. As for NOAA, the agency is legally in violation of the law by refusing to provide information requested by Congress. Moreover, what are they afraid of? If they haven’t been tampering with the data improperly, they should have no reason to resist the congressional investigation. That they are stonewalling it suggests that they are hiding something. It also suggests that they haven’t the faintest idea what the scientific method is, which requires total transparency so that others can check the results and make sure they are correct.

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Flying over Ceres

8:43 am

The Dawn science team has released a new animation using the images taken by the spacecraft. The colors have been enhanced to emphasize the geological differences on the surface. I have embedded it below the fold.

The movie was produced by members of Dawn’s framing camera team at the German Aerospace Center, DLR, using images from Dawn’s high-altitude mapping orbit. During that phase of the mission, which lasted from August to October 2015, the spacecraft circled Ceres at an altitude of about 900 miles (1,450 kilometers).

» Read more

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Antarctic fungi survive Martian conditions on ISS

10:31 am

A European experiment on ISS has found that fungi from Antarctica can survive in a Mars-like environment.

For 18 months half of the Antarctic fungi were exposed to Mars-like conditions. More specifically, this is an atmosphere with 95% CO2, 1.6% argon, 0.15% oxygen, 2.7% nitrogen and 370 parts per million of H2O; and a pressure of 1,000 pascals. Through optical filters, samples were subjected to ultra-violet radiation as if on Mars (higher than 200 nanometres) and others to lower radiation, including separate control samples. “The most relevant outcome was that more than 60% of the cells of the endolithic communities studied remained intact after ‘exposure to Mars’, or rather, the stability of their cellular DNA was still high,” highlights Rosa de la Torre Noetzel from Spain’s National Institute of Aerospace Technology (INTA), co-researcher on the project.

Does this prove that life exists on Mars? Not at all (though I wouldn’t be surprised if we see news articles in the mainstream press over the next week suggesting exactly that). It does show us once again that life is resilient and could develop in many very extreme environments.

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Comet 67P/C-G’s active surface

9:28 am

Comet 67P/C-G's active surface

Cool image time! The Rosetta science team today released a spectacular image, taken by Rosetta’s high resolution camera, of the surface of Comet 67P/C-G. A cropped version is above and below the fold. A cropped version of the full image, focusing in on the smooth and active area dubbed Imhotep, is above.

This smooth dusty terrain, which covers about 0.8 sq km, is etched with curvilinear features stretching hundreds of metres and which have been found to change in appearance over time. Many large boulders are also seen scattered within the smooth terrain, including the boulder Cheops in the foreground. Smaller but more numerous boulders are associated with exposed cliff faces and are most likely the product of erosion. In some debris falls, detailed analysis has revealed the presence of water ice.

I have also included, below the fold, a second close-up crop from this same image, showing the layered cliffs to the left of Imhotep as well as several mysterious as-yet not understood round features at the cliff’s base.
» Read more

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Dantu Crater on Ceres

11:30 am

bright areas on crater wall on Ceres

Cool image time! As Dawn continues its close survey of Ceres, the science team has released this image of Dantu Crater, showing the bright spots on its rim as well as fractures on the crater floor. The picture was taken in December and has a resolution of about 120 feet per pixel.

Though scientists now favor salt deposits of some kind as the cause of the bright areas on Ceres, they also recognize that this theory is not yet proven. Moreover, the theory suggests that the salt was deposited as part of a water brine. When the water in the brine evaporated away, it left the salt behind. The problem, however, is that we do not yet have direct evidence that there is any water on Ceres at all, either on the surface or in the interior, which makes this theory exceedingly uncertain.

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Astronomers propose Neptune-sized planet in Kuiper Belt

9:13 am

The uncertainty of science: Using the orbital data of many recently discovered Kuiper Belt objects [KBOs], two astronomers have proposed the existence of a planet ten times the mass of the Earth and orbiting the sun every 20,000 years.

Trujillo and Sheppard had noted that Sedna, VP113, and several other KBOs all shared a peculiar property: their closest approach to the Sun lay in the plane of the Solar System, and they all moved from south to north when crossing that plane. Batygin and Brown analyzed the orbits further and discovered that their long axes were physically aligned, too, as if something had nudged them to occupy the same region of space around the Sun. The team concluded that a massive object must be shepherding the objects. “We have a gravitational signature of a giant planet in the outer Solar System,” Batygin says.

Planet Nine — informally known as Phattie — is probably smaller than Neptune and icy with a gassy outer layer. The gravitational effect of Uranus and Neptune would have flung it outward in the first 3 million years of the Solar System’s existence, Batygin says.

Be warned! The existence of this as-yet unseen giant planet is quite uncertain. The orbits of the KBOs they are using to postulate its existence have only been observed for a very short period and have not been completely mapped. Thus, those orbits themselves are very uncertain. Moreover, we so far have a very incomplete census of the Kuiper Belt. The orbital behavior used as evidence of another planet could also be caused by many other known factors that have not yet been observed.

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Fraud detected in science research that suggested genetically modified crops were harmful

9:34 am

The uncertainty of peer review: Three science papers that had suggested that genetically modified crops were harmful to animals and have been used by activist groups to argue for their ban have been found to contain manipulated and possibly falsified data

Papers that describe harmful effects to animals fed genetically modified (GM) crops are under scrutiny for alleged data manipulation. The leaked findings of an ongoing investigation at the University of Naples in Italy suggest that images in the papers may have been intentionally altered. The leader of the lab that carried out the work there says that there is no substance to this claim.

The papers’ findings run counter to those of numerous safety tests carried out by food and drug agencies around the world, which indicate that there are no dangers associated with eating GM food. But the work has been widely cited on anti-GM websites — and results of the experiments that the papers describe were referenced in an Italian Senate hearing last July on whether the country should allow cultivation of safety-approved GM crops. “The case is very important also because these papers have been used politically in the debate on GM crops,” says Italian senator Elena Cattaneo, a neuroscientist at the University of Milan whose concerns about the work triggered the investigation.

I know I am generalizing here and have not actually researched this, but I would bet that many of those same anti-GM websites and the people who support them are also firm believers in human-caused global warming. Similarly, I would guess that if you asked these scientists above who wrote the anti-GM papers they also would be firm believers in human-caused global warming. I know this is a guess, but based on years of watching these political battles I think a very safe guess.

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A river on Mars

11:02 am

A river on Mars

Cool image time! The science team for the high resolution camera on Mars Reconnaissance Orbiter this week released it monthly set of cool images. One of those images, which I have cropped and reduced to show it here, is of an ancient river on Mars, the formation process of which geologists still debate. As the scientists note,

The channel pattern, called “dendritic” because of its tree–like branching, begins at the top of the image and runs down over the rim of an ancient impact basin across the basin floor. The soil surface overlying these channels, and indeed the entire landscape, has been changed and reworked over the intervening millions of years, by the combined actions of wind and ice. Over time, the original channels become muted or even erased.

One thing I learned in writing an article for Astronomy about the rivers seen on Saturn’s moon Titan is that without plant life there is no known natural process to hold river banks in place. Instead, if the grade is shallow and not confined by bedrock cliffs, rivers will meander about randomly forming braided channels as there will be nothing on shore to hold the water within the same course. For example, on a lifeless Earth the water draining the central basin of the midwest United States would have flowed south across a wide scattered area covering the entire plains, rather than flowing within the courses of the Missouri and Mississippi rivers.

Thus, it is not surprising that this river on Mars appears muted or partly erased. It probably was never very clearly delineated in the first place.

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Most powerful supernovae ever

6:56 pm

The uncertainty of science: Astronomers have discovered the most powerful supernovae ever detected.

This one, called ASASSN-15lh, is about 3.8 billion light years away, 200 times more powerful than most supernovas, and twice as bright as the previous record holder. It shines 20 times brighter than the combined output of the Milky Way’s 100 billion stars, and in the last six months, it has spewed as much energy as the sun would in 10 lifetimes, says Krzysztof Stanek of the Ohio State University, co-principal investigator of the All Sky Automated Survey for SuperNovae (ASAS-SN) network that spotted the explosion. “This is really on steroids, and then some,” he says. “If it was in our own galaxy, it would shine brighter than the full moon; there would be no night, and it would be easily seen during the day.”

At the moment astronomers don’t really have an theory to explain how the supernovae could produce that much energy.

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Water behavior on Comet 67P/C-G

9:12 am

A new paper based on accumulated data from Rosetta has given scientists a better understanding of the behavior of water ice on Comet 67P/C-G, including the process by which it escapes and is also covered by dust on the surface.

Although water vapour is the main gas seen flowing from comet 67P/Churyumov–Gerasimenko, the great majority of ice is believed to come from under the comet’s crust, and very few examples of exposed water ice have been found on the surface. However, a detailed analysis by Rosetta’s VIRTIS infrared instrument reveals the composition of the comet’s topmost layer: it is primarily coated in a dark, dry and organic-rich material but with a small amount of water ice mixed in.

In the latest study, which focuses on scans between September and November 2014, the team confirms that two areas several tens of metres across in the Imhotep region that appear as bright patches in visible light, do indeed include a significant amount of water ice. The ice is associated with cliff walls and debris falls, and was at an average temperature of about –120ºC at the time.

Note that many media sources today are falsely reporting the “discovery” of water by Rosetta on the comet. This is ridiculous, as water has been detected there for years. To suggest that “discovery” indicates a remarkable level of stupidity and ignorance by these news organizations about science. Either they think their readers are dumb, or they themselves don’t know anything.

Unfortunately, I worry that the answer is both.

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Crater close-ups from Dawn

9:38 am

Kupalo Crater on Ceres

The Dawn science team today released a set of close-up images of several craters on Ceres, showing a number of geological features similar but different than features seen in lunar craters.

The image on the right, of Kupalo Crater, shows the same kind of bright material on the rim that is seen on the floor of Occator Crater as two bright areas. The bright material is now believed to be a salt deposit leeched from beneath the surface. Other craters showed extensive fractures in their floor as well as lobes and scarps.

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Was the Wow! signal from two comets?

10:35 pm

One of the most baffling radio astronomical detections, dubbed the “Wow! signal” and that some believe could have been caused by an extraterrestrial transmission, is now theorized to have been caused by two comets, not an alien civilization.

Antonio Paris, a professor of astronomy at St Petersburg College in Florida, thinks the signal might have come from one or more passing comets. He points the finger at two suspects, called 266P/Christensen and P/2008 Y2 (Gibbs). “I came across the idea when I was in my car driving and wondered if a planetary body, moving fast enough, could be the source,” he says.

Comets release a lot of hydrogen as they swing around the sun. This happens because ultraviolet light breaks up their frozen water, creating a cloud of the gas extending millions of kilometres out from the comet itself. If the comets were passing in front of the Big Ear in 1977, they would have generated an apparently short-lived signal, as the telescope (now dismantled) had a fixed field of view. Searching that same area – as subsequent radio telescopes did – wouldn’t show anything. Tracing the comets’ positions back in time, Paris says that the possible origin for the Wow! signal falls right between where they would have been.

Neither comet was known in 1977; they were both discovered in the last decade, which would mean nobody would have thought to search for them.

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Philae officially dead

10:23 pm

After another attempt to contact Rosetta’s lander Philae ended with no response, engineers now consider the spacecraft dead

“We did not hear anything,” says lander manager Stephan Ulamec. In the best-case scenario, Philae may have received the command and moved, but be unable to respond due to a damaged transmitter. It is more likely that the signal was not received. The team will try a few more commands, but it looks like Philae has officially gone. “We have to face reality, and chances get less and less every day as we are getting farther and farther away from the sun,” says Ulamec. “At some point we have to accept we will not get signals from Philae anymore.”

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Mighty Saturn

11:15 am

Saturn

Cool image time! Be sure to click on this link to see the full resolution Cassini version of the image on the right. Its resolution is 10 miles per pixel, and even so the giant planet cannot be fit in the frame.

One moon, Tethys, is visible, though to make it so required its brightness to be increased by 2. Also, if you look close at the bands at the north pole you can see their strange still-not-understood pentagon shape.

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Mold on ISS plants

9:26 am

In December four of seven zinnia plants in a greenhouse on ISS became sickly or died because they were receiving too much water and developed mold.

The story doesn’t really tell us much, but this paragraph reveals I think some fundamental management problems in the way NASA is running the station:

ISS commander and NASA astronaut Scott Kelly reported the mold to Mission Control Dec. 22 just as Veggie principal investigator Trent Smith was trying to manage the water problem. In pictures, Smith saw water on the plants a few days before. He told Discovery News he was trying to relay a command from NASA’s station operations team to increase fan speed in Veggie, but the mold developed before the command could be put through. One solution was, on Christmas Eve, to designate Kelly “commander” of Veggie. Kelly now has more autonomy to make changes to Veggie’s conditions if he feels the plants need it.

The scientist noticed a problem but was unable to cut through the communications bureaucracy to talk to the astronauts so that changes could be made quickly. Meanwhile, the astronauts on board ISS had not been given the freedom to make common sense changes themselves. The result is that some of the plants died.

The solution, to give an astronaut more “autonomy”, is one that the Russians learned a long time ago on their Mir space station. It was also a lesson NASA learned even longer ago on Skylab. Moreover, when astronauts are finally flying interplanetary spaceships to the planets with greenhouses just like this, they will have to have that autonomy, no matter what rules NASA establishes. It seems amazing to me that NASA is still learning this lesson now.

One more thought: It is not really a problem that the scientist had trouble reaching the astronauts quickly. In fact, it probably indicates an area of management that NASA is handling well. Communications from the ground up to ISS can be a major problem, as everyone wants to talk to the astronauts and if NASA didn’t control that communications the astronauts would never have time to do anything. Thus, placing limits on that communications makes sense, though once again it also requires that the astronauts be given a great deal of freedom to make their own decisions, as they might not be able to talk to the right experts whenever necessary.

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Betelgeuse baffles astronomers

9:10 am

The uncertainty of science: New data of the red giant star Betelgeuse says that the star simply doesn’t have the energy to eject the large amount of gas it routinely blows into space.

“[W]e now have a problem”, says Graham Harper, an astrophysicist at the University of Colorado Boulder. “If you’re going to eject matter you have to put energy in, and we’re not seeing that.” Harper and his colleagues used the US–German Stratospheric Observatory for Infrared Astronomy (SOFIA), a 2.5-metre telescope that flies in a modified Boeing 747 aeroplane, to take Betelgeuse’s temperature. They found that the star’s upper atmosphere was much cooler than expected — so cool, in fact, that it doesn’t seem to have enough energy to kick gas out of its gravitational pull and into space.

“This challenges all our theoretical models,” Harper said on 7 January at a meeting of the American Astronomical Society in Kissimmee, Florida. [emphasis mine]

The data suggests the temperature of the ejected gas to be only about 512 degrees Fahrenheit. This is far too cool to fit any theory for explaining the vast amounts of gas that the star routinely puffs into space. It also suggests, not surprisingly, that scientists do not yet have a enough information to develop a clear understanding of stellar evolution. They have enough information to form rough theories, but there is still much too much they do not know.

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One last chance for Philae

8:56 am

With time running out as Comet 67P/C-G moves away from the Sun, the Rosetta engineering team is going to try one more time to contact the lander Philae.

The lander team are going to try another method to trigger a reponse from Philae: on 10 January they will send a command, via Rosetta, to attempt to make Philae’s momentum wheel switch on. “Time is running out, so we want to explore all possibilities,” says Stephan Ulamec, Philae lander manager at DLR. Philae’s momentum wheel ensured that it was stable during its descent from the orbiter on 12 November, 2014.

If the command is successfully received and executed, the hope is that it might shift the lander’s position.”At best, the spacecraft might shake dust from its solar panels and better align itself with the Sun,” explains Philae technical manager Koen Geurts at DLR’s lander control centre.

They also believe that one of the lander’s two transmitters and one of its two receivers are broken, which makes communications difficult at best.

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Sunspot decline continues

12:06 pm

NOAA’s monthly update of the solar cycle, showing the Sun’s sunspot activity in December, was posted earlier this week, and I am posting it here, as I do every month, with annotations to give it context.

The decline in sunspots continues, tracking closely the rate of decline predicted by the 2007 and 2009 predictions (the lower green curve and the red curve) but the overall solar maximum has been far shorter and less powerful than predicted.
» Read more

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How to really look for aliens

11:38 am

Two scientists summarize the challenge for finding alien life in the universe.

Look for high amounts of oxygen and mid-infrared energy, the second of which has already produced some candidates.

A recent large survey by the Wide-field Infrared Survey Explorer (WISE) satellite did identify five red spiral galaxies whose combination of high MIR and low near-ultraviolet luminosities are inconsistent with simple expectations from high rates of star formation. A conventional explanation for these observations, such as the presence of large amounts of internal dust, has not been ruled out, however. Such peculiar objects deserve follow-up observations before we explore whether they might represent the signatures of galaxy-dominating species.

The article is very thoughtful, however, and outlines in detail the issues and problems the research faces. We might, in a few decades, have the capability to answer this question, but then, the aliens might be alien enough to still be undetectable. Or they might not exist at all.

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