Tag: science

Combined Earth-Space radio array discovers superhot quasar interior

11:01 am

The uncertainty of science: Data obtained by combining four ground-based radio telescopes with the Russian orbiting RadioAstron 10-meter radio telescope have detected temperatures of 10 trillion degrees in the quasar 3C 273, a hundred times hotter than predicted possible by theory.

Supermassive black holes, containing millions to billions times the mass of our Sun, reside at the centers of all massive galaxies. These black holes can drive powerful jets that emit prodigiously, often outshining all the stars in their host galaxies. But there is a limit to how bright these jets can be – when electrons get hotter than about 100 billion degrees, they interact with their own emission to produce X-rays and Gamma-rays and quickly cool down.

Astronomers have just reported a startling violation of this long-standing theoretical limit in the quasar 3C 273. “We measure the effective temperature of the quasar core to be hotter than 10 trillion degrees!” comments Yuri Kovalev (Astro Space Center, Lebedev Physical Institute, Moscow, Russia), the RadioAstron project scientist. “This result is very challenging to explain with our current understanding of how relativistic jets of quasars radiate.”

In addition, the higher resolution of the radio images produced by this space/ground-based array was good enough to see the effect produced by the structure of the interstellar material between here and the quasar.

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Video suggests Hitomi tumbling in orbit

9:17 am

Video taken by an amateur astronomer of Hitomi shows it spinning out of control, another indication that something catastrophic occurred to the newly launched X-ray telescope.

The video shows an object that looks like Hitomi, which lost contact Saturday with the Japan Aerospace Exploration Agency (JAXA), shining and then turning extremely dark in short intervals. The wild changes in brightness might mean its sunlight-reflecting side is moving turbulently. “The fact that it is rotating with extreme variations in brightness indicates that it is not controlled and that some event caused it to begin its rotation,” Paul Maley, a former NASA flight controller who observed Hitomi from the ground in Arizona, was quoted as saying.

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Debris spotted near Hitomi

8:31 am

U.S. military observations have detected debris near the Japanese X-ray telescope Hitomi that has failed to respond to communication signals.

The U.S. Joint Space Operations Center on Sunday said it has spotted five objects floating near Japan’s brand new Hitomi X-ray astronomy satellite that lost communication with Earth the previous day. In a Twitter post, the center, which tracks objects in orbit, said it identified five pieces of “break up” debris in the vicinity of the satellite.

None of this sounds encouraging.

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TMT consortium considers India for telescope

6:10 pm

India is now a second candidate location to replace Hawaii for the Thirty Meter Telescope.

Hanle in Ladakh has been short-listed as a prospective site by the TMT board following major hurdles in Mauna Kea, Hawaii – the first choice for the project. An international team is expected to visit Ladakh in a couple of months. … India is already building edge sensors, actuators and system support support assemblies, besides contributing to the software of TMT. India is expected to invest $212 million in the project.

Not only is India contributing technology and money to the telescope, institutes in the country are also participating in the consortium.

Two major scientific institutions – the Indian Institute of Astrophysics (IIA) Bengaluru and the Inter-University Centre for Astronomy and Astrophysics (IUCAA), Pune – along with two government departments having working on the project since 2013. The department of science and technology (DST) and the Department of Atomic Energy (DAE) are the government partners, while IIA is the nodal agency.

I think the odds continue to increase that TMT will abandon Hawaii, especially since the state government there continues to drag its feet.

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No communications with new Japanese X-ray telescope

8:25 am

Bad news: Engineers have not been able to establish communications with Japan’s new X-ray telescope, Hitomi, since it was launched last month.

The JAXA announcement is very terse, and somewhat unclear, as its wording suggests that communications were not scheduled to begin until yesterday, even though the spacecraft was launched February 17. To me that does not sound right. Regardless, failure to establish communications at the beginning of a flight is usually a very bad thing, as it usually means something fundamental failed at launch and is thus difficult to fix or overcome.

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Frozen pond on Pluto

8:40 am

Cool image time! The New Horizons’ science team on Thursday released a new image, showing a remarkable frozen pond on Pluto. As they note:

“In addition to this possible former lake, we also see evidence of channels that may also have carried liquids in Pluto’s past,” said Alan Stern, Southwest Research Institute, Boulder, Colorado—principal investigator of New Horizons and lead author of a scientific paper on the topic submitted to the journal Icarus.

This feature appears to be a frozen, former lake of liquid nitrogen, located in a mountain range just north of Pluto’s informally named Sputnik Planum. Captured by the New Horizons’ Long Range Reconnaissance Imager (LORRI) as the spacecraft flew past Pluto on July 14, 2015, the image shows details as small as about 430 feet (130 meters). At its widest point the possible lake appears to be about 20 miles (30 kilometers) across.

I have not posted the image here, because I have already posted this image on Behind the Black, back on October 6, 2015, in which I wrote in part,

The image shows what looks like an enclosed lake of some material, probably nitrogen, with the bedrock entrapping it solid ice. In addition, as you move away from the shore and head uphill it looks like you travel across several geological layers made of different materials. Figuring out how they formed in this way could probably keep a geologist busy for his or her entire life.

I had also then noted how I expected the scientists would be “drooling” over this image, and that I expected a full press release on it at some point. It took six months, but here we are.

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ISS astronaut to steer rover on Earth

3:25 pm

On to Mars! The British have enlisted the skills of astronaut Tim Peake on ISS to do some test driving of a prototype rover planned for launch on the second ExoMars mission in 2018.

Major Peake will operate Bruno remotely from the International Space Station. His mission will be to drive the robot into a make-shift cave, which will replicate the conditions on Mars, where he will seek out targets marked with an “X”. “There are caves on Mars and craters that cast long shadows,” said Airbus Defence & Space communications director Jeremy Close. “To explore those areas, it’s more efficient to have a human in the loop.”

I must be a bit of a skeptical grump here: Looking at this story I found it packed with more public relations junk than you can imagine. The whole test facility shown is absurd. All show, no reality. Also, their claims about the rover’s route-finding superiority don’t sound right to me.

And the rover itself? This is the prototype of what they plan to launch in 2018? You have got to be kidding? We are less than two years from launch. While I grant this is probably only a model for testing the robot’s route-finding capability, using something held together by packing tape at this late date hardly fills me with confidence about the final product.

Hat tip John Batchelor for sending me the link.

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Vast Martian dune fields

11:01 am

Olympia Undae dune field

Cool image time! In the past few days the Themis camera on Mars Odyssey has taken two pictures of the vast Olympia Undae dune field near Mars’s north pole. The image to the right is only a cropped, lower resolution section of one of those images.

The image was taken during the summer, so most of the winter CO2 frost has sublimated away. Unfortunately, the website does not provide a scale, though they say the full images each cover about 12 by 43 miles of territory. Yet, both images capture only very tiny portions of the dune field, which apparently goes on and on for many hundreds of miles in all directions, looking exactly the same wherever you look.

Just imagine trying to travel though this area. It is the epitome of a trackless waste. And without some form of GPS system getting lost forever would be incredibly easy.

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Cosmic rays cause the red in Jupiter’s Great Red Spot

10:07 am

New ground-based chemistry research suggests that the bombardment of cosmic rays in Jupiter’s upper atmosphere could be the cause of the red color of the gas giant’s Great Red Spot.

They found that one of the spot’s major components, ammonium hydrosulfide, breaks down when exposed to that radiation in such a way that it turns red. They also think that ultraviolet radiation, also prevalent in space, will do the same.

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Another Rosetta close-up of Comet 67P/C-G

9:50 am

Close-up Comet 67P/C-G

Cool image time! As Rosetta completes a several weeks of in-close observations it took the above oblique view (cropped and reduced to show here) of Comet 67P/C-G. The image was taken from about 7.5 miles with a resolution of about 3 feet per pixel. It shows the Imhotep flat area with the large 80-foot-high Cheops boulder in the center. It is worthwhile to compare this image with one taken in January.. Though the angle is far different, you can recognize the same areas in Imhotep where some of the surface has apparently evaporated away.

What I especially like about today’s image is that it really gives one a feel for what it would be like to stand on the surface here. The light gravity allows some strange rock configurations, such as that giant weird balancing outcrop on the horizon. If you were standing in Imhotep that outcrop would hang above you threateningly.

The spacecraft is now moving away from the comet for the next few weeks

Following the brief encounter at these close distances, Rosetta is now heading out on an anti-sunward excursion to around 1000 km to investigate the comet’s wider coma, tail and plasma environment. Today, 24 March, Rosetta is already over 200 km away from the comet. The current plan is for Rosetta to make a 30 km zero phase flyby around 9 April, before entering back into closer bound orbits by 21 April.

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New Horizons’ future research goals

9:15 am

On Monday at a planetary science conference Alan Stern, the project scientist for New Horizons, outlined the science goals in studying the Kuiper Belt should the spacecraft’s mission be extened through 2021.

The main goal will be the January 1, 2019 fly-by of Kuiper Belt object 2014 MU69, estimated to be between 12 to 24 miles across. However, the proposal also includes the following:

“In addition to making a close flyby of MU69, we’re also going to be close enough in range to study quite a number of other small KBOs, and some large ones that are on the Pluto scale,” Stern said. New Horizons will be able to study them in ways that could never be accomplished from Earth. The closeness of the spacecraft will enable high resolution observations, and the ability to look for satellites that cannot be seen from Earth observatories or with the Hubble Telescope.

“Because we are looking back on the rest of the solar system, at the Kuiper Belt and the Centaur Population,” Stern said, “we’re going to be able to study another 18 or 20 small bodies to determine whether or not the recently discovered rings around the centaur Chariklo are a common occurrence, or something anomalous. And I don’t know of any other way over the next several years, except through New Horizons, that we can develop a data set like that.”

What I find amazing is that it appears from Stern’s remarks that NASA has not yet approved this proposal. Before the team discovered 2014 MU69, I would have been more skeptical about extending the mission, but since they will be able to do a close fly-by of a type of object never before seen, and considering the time and cost it takes to get to the Kuiper Belt, it seems foolish now to not approve this mission extension.

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House proposes killing Commerce Department

9:00 am

In a just released budget resolution, the House budget committee has proposed eliminating the Department of Commerce in an effort to cut costs.

The biggest potential shift from the status quo would be breaking up the $9 billion commerce department. DOC is one of the least-known, and most unloved, of all federal agencies. But it nonetheless oversees a huge scientific portfolio that includes the National Oceanic and Atmospheric Administration (NOAA), the National Institute of Standards and Technology (NIST), and the Census Bureau. Under the heading “options worthy of consideration,” the budget committee suggests moving NOAA to the Department of Interior, placing NIST within NSF, and assigning the Census Bureau, including the massive decennial census, to the Department of Labor’s Bureau of Labor Statistics. Another commerce agency, the U.S. Patent and Trademark Office, would become an independent agency.

The obvious goal would be to eliminate the expensive upper management positions at Commerce and thus reduce cost. Such changes however are going to face opposition in the privileged science community. While that community has been unable to sustain the growth of its funding in the past decade, it has successfully prevented the elimination of any program or any significant reduction in the science budgets. We shall see if that record will hold in the coming years, with the electorate appearing to steadily shift more and more to the right.

The article, by Science reporter Jeffrey Mervis, also included this wonderful example of yellow journalism:

The proposed budget resolution talks repeatedly of the need to reduce spending and, in particular, curb the clichéd “waste, fraud, and abuse” that is allegedly rampant across the federal government by killing duplicative or unnecessary programs. [emphasis mine]

I’ve noted Mervis’s agenda-driven writing in the past. In the sentence above he illustrates his unreliability as a reporter. For any educated journalist to consider waste and fraud in the federal government to be “alleged” is to be a person either with his head in the sand or having so strong a bias that he is intentionally misreporting the facts. Sadly, in the case of Mervis and many in today’s so-called elite intellectual community, I think it is both.

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Near disaster for ExoMars

6:22 pm

The Russian jinx for going to Mars might not be over yet: New data suggests that the Briz-M upper stage to the Proton rocket exploded shortly after it has propelled ExoMars on its way to Mars and then separated from it.

There appears to be a cloud of debris near the probe, thought to have been caused when the Briz-M stage was to fire its rockets one last time to take it away from ExoMars as well as prevent it from following it to Mars. Instead, it is thought (though not confirmed) that the stage blew up at that moment.

Though so far ExoMars appears to be functioning properly, but they have not yet activated all of its most sensitive instruments. Only when they turn them on in April will we find out if they were damaged in any way by the Briz-M failure.

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New close-up of Occator Crater’s spots

1:57 pm

Occator Crater central spot

The Dawn science team have released new images taken from the spacecraft’s low orbit observations, including a close-up of the central white spot at Occator Crater, the brightest spot on Ceres.

The image on the right is a cropped though full resolution version of the full image. I have reduced it only slightly. As they note,

Occator Crater, measuring 57 miles (92 kilometers) across and 2.5 miles (4 kilometers) deep, contains the brightest area on Ceres, the dwarf planet that Dawn has explored since early 2015. The latest images, taken from 240 miles (385 kilometers) above the surface of Ceres, reveal a dome in a smooth-walled pit in the bright center of the crater. Numerous linear features and fractures crisscross the top and flanks of this dome. Prominent fractures also surround the dome and run through smaller, bright regions found within the crater.

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A new gravity map of Mars

9:06 am

Using data from three orbiting NASA spacecraft scientists have created a new gravity map of Mars, showing the subtle variations in its gravitational field due to density differences within the planet.

The improved resolution of the new gravity map suggests a new explanation for how some features formed across the boundary that divides the relatively smooth northern lowlands from heavily cratered southern highlands. Also, the team confirmed that Mars has a liquid outer core of molten rock by analyzing tides in the Martian crust and mantle caused by the gravitational pull of the sun and the two moons of Mars. Finally, by observing how Mars’ gravity changed over 11 years – the period of an entire cycle of solar activity — the team inferred the massive amount of carbon dioxide that freezes out of the atmosphere onto a Martian polar ice cap when it experiences winter. They also observed how that mass moves between the south pole and the north pole with the change of season in each hemisphere.

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Getting real close to Comet 67P/C-G

9:47 am

Close-up of Comet 67P/C-G

Cool image time! As Comet 67P/C-G moves away from the sun and cools down, the Rosetta science team has been able to move the spacecraft back in close to the comet. The image on the right was taken on March 5 from only 12.6 miles above the comet’s surface, and has a resolution of 14 inches per pixel.

I have brightened the image and cropped it to show it here. At this scale, if they managed to photograph the location where Philae sits we would see it with no problem at all. As it is, the detail is remarkable. For example, look at the slope below the cliff in the lower right. You can see what look like a very faint series of terraces, suggesting the existence of onion-like layers below the surface.

Go to the link. There is a second high resolution image there that is as amazing.

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The Irish not of Celtic origin?

9:06 am

The uncertainty of science: The discovery of a burial site in Ireland has thrown into doubt all theories concerning the Celtic origins of the Irish.

“The DNA evidence based on those bones completely upends the traditional view,” said Barry Cunliffe, an emeritus professor of archaeology at Oxford who has written books on the origins of the people of Ireland. DNA research indicates that the three skeletons found behind McCuaig’s are the ancestors of the modern Irish and they predate the Celts and their purported arrival by 1,000 years or more. The genetic roots of today’s Irish, in other words, existed in Ireland before the Celts arrived.

The article is quite detailed and outlines the overall scientific problem of the Celts, which is now quite unclear about who they were, where they came from, and where they went.

In related news: Scientists have found new evidence of a human presence in Ireland as far back as 12,500 years ago.

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Exoplanet with cometlike orbit

8:57 am

Worlds without end: Astronomers detect an exoplanet with an orbit so eccentric that the orbit is more like a comet’s.

The eccentricity of a planet’s orbit is measured on a scale of 0 to 1, with 0 representing a perfectly circular orbit, and figures closer to one indicative of increasingly elliptical orbits. Earth’s orbital eccentricity, for example, is 0.017, and the most eccentric planet in our solar system – Mercury, assuming that we no longer class Pluto a planet – has an eccentricity of 0.205.

Our new friend, HD 20782, on the other hand, has an orbital eccentricity of 0.96, meaning its ellipse as it travels to and from its star is almost flat; and when it does finally return to its sun, after a 597-day orbital journey, it careers furiously round the star to slingshot back into space. “It’s around the mass of Jupiter, but it’s swinging around its star like it’s a comet,” said Dr. Kane.

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Injected stem cells cure osteoporosis in mice

9:22 am

Scientists have discovered that an injection of stem cells into mice with osteoporosis was able to completely cure them of the bone disease.

Researchers at the University of Toronto and The Ottawa Hospital had previously found a causal effect between mice developing age-related osteoporosis and a deficiency in mesenchymal stem cells (MSCs). One of the promising attributes of MSCs is that, while they can grow into different cells in the body just like other stem cells, they can be transplanted without the need for a match. “We reasoned that if defective MSCs are responsible for osteoporosis, transplantation of healthy MSCs should be able to prevent or treat osteoporosis,” says William Stanford, senior scientist at The Ottawa Hospital and Professor at the University of Ottawa.

To put this reasoning to the test, the scientists injected MSCs into mice with the condition. Six months later, which is one quarter of the life span of the animal, they observed a healthy functional bone in place of the damaged one. “We had hoped for a general increase in bone health,” says John E. Davies, co-author of the study. “But the huge surprise was to find that the exquisite inner ‘coral-like’ architecture of the bone structure of the injected animals – which is severely compromised in osteoporosis – was restored to normal.”

The importance of this discovery for space travel is that it might eventually allow scientists to use it to somehow prevent the loss of bone density during weightlessness.

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First step in producing silicon-based life

9:04 am

The Horta live! Scientists have succeeded in creating a bacteria that can produce hydrocarbon compounds that incorporate silicon into their make-up.

To get biology to adopt silicon, Frances Arnold, a chemist at the California Institute of Technology (Caltech) in Pasadena, along with postdoctoral assistant Jennifer Kan and graduate student Rusty Lewis, started by isolating a so-called thermophilic bacterium, which grows in hot springs. Like many organisms, the bacterium contains an enzyme called cytochrome c, which shuttles electrons to other proteins, making it widely useful in biochemistry. In some cases, however, enzymes in thermophilic bacteria expand their roles to carry out other reactions on the side. So the Caltech researchers tested their microbe and found that in rare cases its cytochrome c also added silicon to hydrocarbons.

In nature, Arnold notes, cytochrome c’s silicon-adding ability is so feeble that it’s probably just a byproduct of the enzyme’s function—not even close to its primary role. To try to beef it up, the team incubated the bacteria with silicon and carbon compounds and selected the organisms that produced the most hydrocarbons that incorporated silicon. After only three rounds of this artificial selection, the enzymes had evolved to churn out silicon-containing hydrocarbons 2000 times as readily as natural cytochrome c. “The power of evolution really shows up when a new function appears and then is forced to adapt via directed evolution,” Arnold says.

For now, the silicon-spiked hydrocarbon compounds, called organosilanes, probably aren’t useful either to the bacteria or to industry. They’re short and stubby, unlike the long chainlike versions that chemical companies make for uses such as adhesives, caulks, and sealants.

As the article notes, they really are very far from creating a silicon-based life. Still, to get silicon incorporated into carbon-based organic chemistry is a significant first step, as it demonstrates that the theory of silicon-based life might very well have merit.

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South Korea commits almost a billion dollars to AI research

8:56 am

In reaction to the recent Go victory by a computer program over a human, the government of South Korea has quickly accelerated its plans to back research into the field of artificial intelligence with a commitment of $863 million and the establishment of public/private institute.

Scrambling to respond to the success of Google DeepMind’s world-beating Go program AlphaGo, South Korea announced on 17 March that it would invest $863 million (1 trillion won) in artificial-intelligence (AI) research over the next five years. It is not immediately clear whether the cash represents new funding, or had been previously allocated to AI efforts. But it does include the founding of a high-profile, public–private research centre with participation from several Korean conglomerates, including Samsung, LG Electronics and Hyundai Motor, as well as the technology firm Naver, based near Seoul.

The timing of the announcement indicates the impact in South Korea of AlphaGo, which two days earlier wrapped up a 4–1 victory over grandmaster Lee Sedol in an exhibition match in Seoul. The feat was hailed as a milestone for AI research. But it also shocked the Korean public, stoking widespread concern over the capabilities of AI, as well as a spate of newspaper headlines worrying that South Korea was falling behind in a crucial growth industry.

South Korean President Park Geun-hye has also announced the formation of a council that will provide recommendations to overhaul the nation’s research and development process to enhance productivity. In her 17 March speech, she emphasized that “artificial intelligence can be a blessing for human society” and called it “the fourth industrial revolution”. She added, “Above all, Korean society is ironically lucky, that thanks to the ‘AlphaGo shock’, we have learned the importance of AI before it is too late.”

Not surprisingly, some academics are complaining that the money is going to industry rather than the universities. For myself, I wonder if this crony capitalistic approach will produce any real development, or whether it will instead end up to be a pork-laden jobs program for South Korean politicians.

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NOAA head poo-poos private weather companies

10:58 pm

At a congressional hearing on Wednesday the head of NOAA expressed serious doubts about the ability of private companies to provide worthwhile weather data.

At a hearing of the environment subcommittee of the House Science Committee on NOAA’s fiscal year 2017 budget request, NOAA Administrator Kathryn Sullivan said it was still too soon to determine if commercial sources of weather data, most notably GPS radio occultation systems, could augment or replace existing data sources. “In the weather domain, we believe it is a promising but still quite nascent prospect to actually have data flows from private sector satellites,” Sullivan said. “There have been a number of claims, there’s some hardware in orbit from at least one company that I’m aware of, but really nothing proven to the level that we require for ingesting something into the National Weather Service.”

This so much reminds me of past NASA administrators who repeatedly told us that private companies really couldn’t do the job of supplying ISS or launching humans into space, and that we really needed to leave that job to the government, which really knew better.

As it turns out, those past NASA administrators were wrong. Not only has private space done a very effective job at supplying ISS, they made it happen fast for relatively little money. And they are about to do the same in launching humans into space as well. NASA meanwhile has been twiddling its thumbs for decades in its efforts to replace the space shuttle while spending ungodly amounts of money and accomplishing little with it.

I have no doubt the same will be true with the weather. Allow private companies to compete for profits in providing the world with good weather data, and they will quickly do a far better job than NOAA. And the data will likely not be tampered with for political ends by global warming advocates in the government!

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Pluto 8 months after fly-by

12:04 pm

The New Horizons science team today published five papers summarizing what they have so far learned from the data obtained during last year’s July 14 fly-by and since downloaded.

Two of the many discoveries are to me the most interesting: The first illustrates Pluto’s strange and very active geology:

Age-dating of Pluto’s surface through crater counts has revealed that Pluto has been geologically active throughout the past 4 billion years. Further, the surface of Pluto’s informally named Sputnik Planum, a massive ice plain larger than Texas, is devoid of any detectable craters and estimated to be geologically young – no more than 10 million years old.

Moreover, the materials that cause Pluto to be geologically active are much more complicated than anything on Earth:

Scientists studying Pluto’s composition say the diversity of the planet’s landscape stems from eons of interaction between highly volatile and mobile methane, nitrogen and carbon monoxide ices with inert and sturdy water ice. “We see variations in the distribution of Pluto’s volatile ices that point to fascinating cycles of evaporation and condensation,” said Will Grundy, from Lowell Observatory in Flagstaff, Arizona, and lead author of the composition paper. “These cycles are a lot richer than on Earth, where there’s really only one material that condenses and evaporates – water. On Pluto, there are least three materials, and while they interact in ways we don’t yet fully understand, we definitely see their effects all across Pluto’s surface.”

The second discovery that fascinates me has to do with the formation of Pluto and all its moons:

The high albedos (reflectiveness) of Pluto’s small satellites are entirely different from the much lower albedos of the small bodies in the general Kuiper Belt population (which range from about 5 to 20 percent). This difference lends further support to the idea that these satellites were not captured from the general Kuiper Belt population, but instead formed by agglomeration in a disk of material produced in the aftermath of the giant collision that created the entire Pluto satellite system.

In other words, Pluto and its moons are not a collection of different Kuiper Belt objects brought together over time. Instead, they formed together.

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ULA head rejects his engineer’s remarks about Aerojet Rocketdyne

9:47 pm

The heat of competition: The head of ULA has disavowed his engineers’ remarks that plugged Blue Origin’s engine for the Atlas 5 while dissing Aeroject Rocketdyne’s.

The engineer was giving a talk at the University of Colorado this week where he made it pretty clear that ULA favors Blue Origin over Aerojet Rocketdyne, but had to make believe they were treating both companies equally in the competition to replace the Atlas 5’s Russian engines in order to keep the Air Force happy. Bruno is probably now doing some damage control, as the government still wants to justify the Aerojet Rocketdyne contract (whose only real purpose was as a government pork barrel jobs program). Considering all the money the Air Force and congressmen give to ULA, he has to keep them both happy. And telling the world that their Aerojet contract is a waste of government money is not a very good way to do this.

Nonetheless, he also admitted that Blue Origin is way ahead in development, and is thus most likely to win the competition anyway.

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Changes in Ceres’s white spots

3:56 pm

The uncertainty of science: Ground-based observations of Ceres now suggest that the white spots imaged by Dawn undergo subtle unexpected variations

As Ceres rotates every 9 hours, HARPS is so sensitive that it can detect the very slight Doppler shift in spectrum frequency as the bright spots rotate toward and away Earth, but during observations for 2 nights in July and August 2015, more changes not related to Ceres’ spin were detected. “The result was a surprise,” said co-author Antonino Lanza, also from the INAF–Catania Astrophysical Observatory. “We did find the expected changes to the spectrum from the rotation of Ceres, but with considerable other variations from night to night.”

And it appears that these changes are consistent with some kind of volatile (ice) being exposed to sunlight and venting vapor into space, causing an increase in reflectivity. It seems that when Occator experiences solar heating, plumes are produced and then evaporate, creating a complex spectroscopic signal that evolves during that hemisphere’s daytime. This finding appears to be consistent with earlier observations made by Dawn showing a mysterious haze over Occator.

The problem with this theory is that it assumes the white spots are comprised of water ice. However, data from Dawn has instead suggested that the white spots are not water but salt deposits.

It could be that the white spots are salt left behind when water vented from inside Ceres evaporates away, but so far the data from Dawn has not found any evidence of water at the spots. If it was venting there, Dawn should have seen it.

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