Tag: science

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).

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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.
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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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Four elements added to periodic table

8:30 am

Scientists have now officially added four new elements to the periodic table, completing the discovery of all elements through 118.

All of the elements were created in the lab, by smashing lighter atomic nuclei together. The unstable agglomerations of protons and neutrons last mere fractions of a second before they fall apart into smaller, more stable fragments.

The teams that have been given credit for the discoveries can now put forward proposals for the elements’ names and two-letter symbols. Elements can be named after one of their chemical or physical properties, a mythological concept, a mineral, a place or country, or a scientist. Priority for discovering element 113 went to researchers in Japan, who are particularly delighted because it will become the first artificial element to be named in East Asia. When the element was first sighted 12 years ago, ‘Japonium’ was suggested as a name.

While creating element 119 is believed possible, beyond that it is thought unlikely that anything heavier can be produced in the lab.

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Seeds from archaeological site grow into extinct squash

10:18 am

Update: It appears the story below is bogus. (Hat tip Pzatchok.) It appears to be a combination of two different stories, one in which gardeners from the Miami Nation in Indiana donated old seeds to a research group, and the second where that same research group attempted to grow seeds found in a Kentucky cave, with poor results.

Original post:
Students who discovered some ancient seeds in a clay pot at an archaeological site in Canada successfully planted them to grow a previously extinct species of squash.

Not all the seeds grew, but enough did. Moreover, the new squash produced new seeds. This once extinct squash is no longer extinct. And according to the article is also tastes delicious!

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Science journal publishes fake study

11:06 am

The uncertainty of peer review: A science journal has published a fake study that supposedly proved that kissing a child’s “boo-boo” has no medicinal value.

In their study, the authors claim to be members of the Study of Maternal and Child Kissing (SMACK) Working Group, which they say is a subsidiary of Procter and Johnson, Inc., the maker of “Bac-Be-Gone ointment and Steri-Aids self-adhesive bandages.” Procter and Johnson, which is not a real consumer goods company, is an obvious mash-up of Procter & Gamble and Johnson & Johnson, two consumer packaged goods companies which sell health care items like bandages and ointments. The only contact information for the study’s authors disclosed in the research paper is a Gmail address. Bac-Be-Gone ointment and Steri-Aids also do not appear to be actual products available for sale. Additionally, many of the academic research references listed at the end of the study–including one article entitled “So what the hell is going on here?”–also appear to be fake.

The journal, the Journal of Evaluation in Clinical Practice, claims on its website that all papers published by it are copy-edited and peer-reviewed. In this case I suppose the reviewers worked for Comedy Central .

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U.S. production of plutonium-238 resumes

7:10 pm

After a 30 year hiatus, the Department of Energy has produced the first plutonium-238 in the United States since the late 1980s.

Plutonium-238 is the fuel of choice for deep-space exploration. But for nearly 30 years, nobody in the United States was making it.

On Tuesday, that all changed. The Department of Energy announced that 50 grams of the stuff had been made by researchers at the Oak Ridge National Laboratory in Oak Ridge, Tenn. Fifty grams isn’t much, but this is the first time the substance has been made in the country since the Savannah River Plant in South Carolina stopped making it in the late 1980s.

What this does is provide NASA and the U.S. the ability to fly unmanned deep space missions for many more years. Without this plutonium-238, there would be no practical way to power spacecraft traveling out beyond Mars orbit.

And why did the U.S. stop making plutonium-238 in the late 1980s? The story is of course complicated, but one of the big factors is that at that time nuclear power had become politically incorrect after the Three Mile Island and Chernobyl nuclear power plant failures, and thus politicians fell over themselves to be the first to ban any such production, even if it was harmless and incredibly beneficial.

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InSight Mars mission suspended

3:14 pm

Because of a serious technical problem with its prime instrument, NASA has decided that its InSight Mars lander will not make its March 2016 launch window and has suspended the mission.

NASA said the decision to delay follows unsuccessful attempts to repair a leak affecting the device, which requires a vacuum seal around its three main sensors to withstand the harsh conditions of the Martian environment. A leak discovered earlier this year, that prevented it from retaining vacuum conditions, was successfully repaired, and the mission team “was hopeful the most recent fix also would be successful.”

However, the instrument once again failed to hold a vacuum during testing on Monday in extreme cold temperature.

It is even possible that the mission will be cancelled entirely because of the problem.

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Images of Ceres from Dawn’s lowest orbit

10:40 am

The Dawn science team has now released new high resolution images of Ceres taken from the spacecraft’s lowest orbit.

Dawn took these images of the southern hemisphere of Ceres on Dec. 10, at an approximate altitude of 240 miles (385 kilometers), which is its lowest-ever orbital altitude. Dawn will remain at this altitude for the rest of its mission, and indefinitely afterward. The resolution of the new images is about 120 feet (35 meters) per pixel.

Among the striking views is a chain of craters called Gerber Catena, located just west of the large crater Urvara. Troughs are common on larger planetary bodies, caused by contraction, impact stresses and the loading of the crust by large mountains — Olympus Mons on Mars is one example. The fracturing found all across Ceres’ surface indicates that similar processes may have occurred there, despite its smaller size (the average diameter of Ceres is 584 miles, or 940 kilometers). Many of the troughs and grooves on Ceres were likely formed as a result of impacts, but some appear to be tectonic, reflecting internal stresses that broke the crust.

Make sure to click on the link. The images show that Ceres is not the dull boring surface that the wider shots have suggested.

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Water unneeded to produce wet gullies on Mars

9:51 pm

The uncertainty of science: New modeling suggests that the wet gullies seen on Mars can be produced by dry ice, not water.

The theory is not completely new, but Cedric Pilorget and François Forget, with the University of Paris-Sud, and Paris’ Pierre and Marie Curie University, respectively, flesh out the idea with some hard numbers. Their new computer model calculates seasonal changes and impacts of an underlying layer of regolith, a carbon dioxide ice layer and the carbon dioxide-dominated gas atmosphere above. The simulation can take into account a variety of latitudes, slopes and other parameters.

The scientists found that most of the gullies could be created in a process that does not require any liquid water.

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