Tag: science

Israeli student cubesat launched from Atlas 5

6:04 pm

When the Cygnus capsule was placed in orbit yesterday, it also released a number of nanosats, one of which was a cubesat built by Israeli high school students.

More than 80 pupils in grades 9-12 at schools in Herzliya, Ofakim, Yeruham, Ofra, and the Bedouin town of Hura helped to construct Duchifat-2, which weighs just 1.8 kilograms (four pounds), and is just 20 centimeters (eight inches) tall and 10 centimeters wide. Due to its small size, the satellite has no motors and instead uses the earth’s magnetic field to keep itself correctly aligned in space.

Cubesats have generally been built and launched as college projects to help teach students the engineering behind satellites. This however was the only nanosat released by the Atlas 5 that involved high school students.

Note also that the project did not simply involve Jewish students.

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Landslides on Ceres reveal presence of ice

4:37 pm

An analysis of data from Dawn has shown that Ceres’s landslides are distributed in greater numbers towards the poles, which suggests the presence of water ice just below the surface.

Georgia Tech Assistant Professor and Dawn Science Team Associate Britney Schmidt led the study. She believes it provides more proof that the asteroid’s shallow subsurface is a mixture of rock and ice. “Landslides cover more area in the poles than at the equator, but most surface processes generally don’t care about latitude,” said Schmidt, a faculty member in the School of Earth and Atmospheric Sciences. “That’s one reason why we think it’s ice affecting the flow processes. There’s no other good way to explain why the poles have huge, thick landslides; mid-latitudes have a mixture of sheeted and thick landslides; and low latitudes have just a few.”

The data also showed that Ceres has far more landslides than expected, which also supports the idea that the shallow subsurface has a lot of water ice in it, as much as 10% to 50% by volume.

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Water plumes on Europa plus hydrogen in Enceladus plumes

4:31 am

Scientists have detected more evidence of underground oceans on both Europa (orbiting Jupiter) and Enceladus (orbiting Saturn).

In the case of Europa, the Hubble Space Telescope has once again detected plumes of water ice being shot up from cracks in the moon’s surface. This second detection confirms the first from two years ago.

In the case of Enceladus, Cassini data has detected the presence of hydrogen in the plumes totaling 1% of the total material in the plumes.

The Europa story is significant, in that it confirms that the moon is still active geologically, and that the underground ocean is interacting with the outside world by ejecting material from it to the surface. This increases the odds that there will be some very intriguing chemistry in that ocean, including the possibility of organic life.

The Enceladus story puzzles me. We already know that the plumes there are made of water, which in itself is one third hydrogen. Why should anyone be surprised that a portion of that water gets split so that some of the hydrogen gets released as an atom instead of part of the water molecule. In fact, this discovery does not seem to me to be much of a discovery at all, but simply a confirmation that the plumes have the materials from the water ocean below the surface. That NASA has pushed it this week so hard in conjunction with their future Europa Clipper mission suggests that this part of the press story is really about lobbying for funds and has little to do with science.

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Sunspot update for March 2017

11:32 am

On April 3, while I was in the Grand Canyon, NOAA posted its monthly update of the solar cycle, covering sunspot activity for March. As I have been doing every month since 2010, I am posting it here with annotations to give it context.

March 2017 Solar Cycle graph

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

The decline in sunspots continues to run below predictions, suggesting an end to this solar cycle and a solar minimum as early as sometime in 2018. And as I noted in my February update, sunspot activity continues to track the Sun’s 27 day rotation, alternating every two weeks between blank and active hemispheres. We had the longest stretch, more than two weeks, without sunspots in March. This was followed by about two weeks of activity, followed by several blank days and a relatively inactive Sun at present, beginning a little less than a week ago. I expect this period of inactivity to last another ten days or so, and then things will pick up again.

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U.S. refuses to sign G7 statement supporting Paris climate accord

9:42 am

In another indication that the Trump administration is going to completely reshape the U.S.’s environmental policy, Energy Secretary Rick Perry refused to sign a statement issued during the G7 meeting in Italy endorsing the Paris climate treaty.

Secretary of Energy Rick Perry said the U.S. “is in the process of reviewing many of its policies and reserves its position on this issue, which will be communicated at a future date,” Italy’s industry and energy minister Carlo Calenda said in a statement. Calenda said other G7 members “reaffirmed their commitment towards the implementation of the Paris Agreement to effectively limit the increase in global temperature well below 2°C above pre-industrial level.”

The Trump administration would not sign onto a statement mentioning Paris, since the president is still deciding whether or not to keep his campaign pledge. Perry also wanted the G7 to include support for coal and natural gas in its statement. “Therefore, we believe it is wise for countries to use and pursue highly efficient energy resources,” Perry said in a statement after his meeting in Rome with energy ministers from Canada, France, Germany, Italy, Japan, the UK and the European Union.

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Scientists find persistent cold spot on Jupiter

8:59 am

In reviewing data for the past fifteen years have scientists have identified an unexpected cold region in Jupiter’s upper mid-latitudes as large as the Great Red Spot.

“The Great Cold Spot is much more volatile than the slowly changing Great Red Spot, changing dramatically in shape and size over only a few days and weeks, but it has re-appeared for as long as we have data to search for it, for over 15 years,” Stallard said. “That suggests that it continually reforms itself, and as a result it might be as old as the aurorae that form it – perhaps many thousands of years old.”

The Great Cold Spot is thought to be caused by the effects of the magnetic field of the planet, with the massive planet’s spectacular polar aurorae driving energy into the atmosphere in the form of heat flowing around the planet.

Though they think the cold region is related to the aurora, I suspect they really do not have enough information to really understand what is going on.

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Sweden delivers science instrument for Chinese lunar probe

8:54 am

The new colonial movement: The Swedish Institute of Physics has completed construction and delivered a science instrument to be flown on China’s Chang’e 4 spacecraft that will bring an orbiter, lander, and rover to the Moon’s far side in 2018.

The instrument will be installed on the rover, and will study the surface and how it interacts with the solar wind. This will also be a continuation of research performed by India’s Chandayaan-1 orbiter.

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New Horizons goes back to sleep

8:43 am

The New Horizons science and engineering team has placed the spacecraft back in hibernation mode for the first time since prior to its fly-by of Pluto in 2014.

During hibernation mode, much of the New Horizons spacecraft is unpowered. The onboard flight computer monitors system health and broadcasts a weekly beacon-status tone back to Earth, and about once a month sends home data on spacecraft health and safety. Onboard sequences sent in advance by mission controllers will eventually wake New Horizons to check out critical systems, gather new Kuiper Belt science data, and perform course corrections (if necessary).

This hibernation period will last until September, when they will wake the spacecraft so that they can make a mid-course correction in preparation for the January 1, 2019 flyby of Kuiper Belt Object 2014 MU69.

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Large archive of Canadian ice cores melts

8:38 am

A large archive of Canadian ice cores has been lost, melting when the freezer they were stored in failed.

The 2 April failure left “pools of water all over the floor and steam in the room,” UA glaciologist Martin Sharp told ScienceInsider. “It was like a changing room in a swimming pool.” The melted cores represented 12.8% of the collection, which held 1408 samples taken from across the Canadian Arctic. The cores hold air bubbles, dust grains, pollen, and other evidence that can provide crucial information about past climates and environments, and inform predictions about the future.

The storage facility is normally chilled to –37°C. But the equipment failure allowed temperatures to rise to 40°C, melting tens of thousands of years of history. Among the losses: some of the oldest ice cores from Mount Logan, a 5595-meter-high mountain in northern Canada. “We only lost 15 meters [of core], but because it was from the bottom of the core, that’s 16,000 years out of the 17,700 years that was originally represented,” Sharp says.

Scientists also lost 66 meters of core from Baffin Island’s Penny Ice Cap, which accounts for 22,000 years—a quarter of the record. That leaves “a gap for the oldest part, which is really the last glaciation before the warming that brought us into the present interglacial,” Sharp says.

Considering the cost and difficulty of drilling these cores, and then safely bringing them to the facility without melting, it seems to me astonishing that the facility did not have back-up freezer capability.

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The storms of Jupiter

9:26 am

The storms of Jupiter

Cool image time! The image on the right, taken by Juno during its fifth close fly-by of Jupiter in late March and cropped to post here, shows two of the major storms in what I think is one of Jupiter’s main large mid-latitude belts. The full image, posted below in a significantly reduced form but annotated by me to indicate the location of the inset, covers a much larger area, but I have specifically zoomed into these two storms to highlight how large these storms are as well as how much detail is hidden within them.

In the bright spot in particular (officially called A6 by planetary scientists) you can see a hint of the existence of innumerable mini-storms. Juno’s camera does not have the resolution to image these smaller storms, but this image suggests that the gas giant’s atmosphere is far far far more complex than we can yet imagine.

Full image of Jupiter reduced and annotated

Unfortunately, these images do not provide a scale. Based on a global image taken by Juno in October 2016 and matching the gas giant’s major horizontal bands, the annotated full image strip on the left appears to cover a little less than a third of Jupiter, from about 10 degrees latitude to about 50 degrees latitude. From this I estimate that if we put the Earth in the inset image it would probably be only slightly larger than the image itself, which means these two storms would cover most of one hemisphere.

In other words, the mini-storms inside the big bright oval are still larger than the biggest hurricanes on Earth, and they are packed together inside a much larger planet-sized storm.

What should fill us with even more awe is that this only covers a very thin slice of the top of Jupiter’s deep atmosphere. The planet itself is about 89,000 miles in diameter, more than ten times larger than Earth. The depth of its atmosphere is not really known, but it must be deeper than several Earths, piled on top of each other. In that depth there must be many atmospheric layers, each thicker and denser than the one above, and each with its own weather systems and complexities.

It will take centuries of research, including the development of new engineering capable of accessing this place, to even begin to map out its meteorology. And this is only one gas giant, of what we now know must be millions and millions throughout the galaxy.

If we have the nerve and daring, the human race has the opportunity to go out there and never be bored. There will always be something unknown to discover.

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Citizen scientists crowd scource discovery of 4 exoplanets

9:05 am

After being promoted on an Australian tv show an effort to use public help to plow through Kepler’s vast archives discovered four new exoplanets within two days.

In three days, the Australia iteration of astronomy TV show Stargazing Live brought us #SpaceGandalf and now its viewers have discovered four planets. After it was promoted on the show, citizen scientists and fans of the program came together to contribute to a crowd-sourcing project, stalking around 100,000 stars on the Zooniverse website, which displays recent data from the Kepler Space Telescope.

And you betcha, in just 48 hours, around 10,000 volunteers discovered scores of potential new planet candidates, with scientists confirming the discovery of four “super-Earth” planets orbiting a star in the constellation of Aquarius.

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Atmosphere detected around Earth-sized exoplanet

9:00 am

Worlds without end: Astronomers have detected an atmosphere around an Earth-sized exoplanet 39 light years away.

The researchers pored over measurements from the European Southern Observatory in Chile and found that at one wavelength band of light, the planet looked larger than at others, as it crossed the face of its parent star. “These things don’t pop up in the way you expect,” said John Southworth, an astronomer at Keele University in the UK. “We found evidence for the atmosphere at one wavelength band and that wasn’t what we were expecting.”

The observations point to an atmosphere that is rich in water or methane, but it will take more measurements with other telescopes to identify the chemicals present.

The planet is about 16% larger than Earth. There remain a lot of uncertainty here with this result, so we should not yet take it too seriously.

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Hubble snaps close-up of Jupiter

4:08 pm

Jupiter by Hubble

Cool image time! The Hubble Space Telescope has taken a magnificent global view of Jupiter. The image on the right is only a thumbnail. Make sure to go to the link to see the full image, which amazingly compares quite favorably with the images being sent down by Juno in orbit around the gas giant.

This Hubble image once again demonstrates the remarkable advantages of an optical telescope in space. Equipped with the right instruments, it could do much of the research now being done by the planetary missions, and do it from Earth orbit.The research possibilities and the knowledge revealed from the ability to see things clearly in the optical bands is truly endless.

Even more important, we are wired to what we see. Give us a good visual image and many questions can immediately be answered.

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New theory eliminates need for dark energy

9:09 am

The uncertainty of science: A new theory now shows that dark energy, the apparent acceleration of the universe’s expansion rate on large scales, does not need to exist in order to explain the data that astronomers have obtained.

In the new work, the researchers, led by Phd student Gábor Rácz of Eötvös Loránd University in Hungary, question the existence of dark energy and suggest an alternative explanation. They argue that conventional models of cosmology (the study of the origin and evolution of the universe), rely on approximations that ignore its structure, and where matter is assumed to have a uniform density. “Einstein’s equations of general relativity that describe the expansion of the universe are so complex mathematically, that for a hundred years no solutions accounting for the effect of cosmic structures have been found. We know from very precise supernova observations that the universe is accelerating, but at the same time we rely on coarse approximations to Einstein’s equations which may introduce serious side-effects, such as the need for dark energy, in the models designed to fit the observational data.” explains Dr László Dobos, co-author of the paper, also at Eötvös Loránd University.

In practice, normal and dark matter appear to fill the universe with a foam-like structure, where galaxies are located on the thin walls between bubbles, and are grouped into superclusters. The insides of the bubbles are in contrast almost empty of both kinds of matter. Using a computer simulation to model the effect of gravity on the distribution of millions of particles of dark matter, the scientists reconstructed the evolution of the universe, including the early clumping of matter, and the formation of large scale structure.

Unlike conventional simulations with a smoothly expanding universe, taking the structure into account led to a model where different regions of the cosmos expand at different rate. The average expansion rate though is consistent with present observations, which suggest an overall acceleration.

In other words, the uneven structure of the universe has never been considered in previous models, and once included in the equations the need for dark energy disappears.

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Less than 1% of all science papers follow scientific method

7:05 pm

The uncertainty of science: A survey of the research done for papers published in scientific peer-reviewed journals has found that less than 1% properly follow the scientific method.

Armstrong defined eight criteria for compliance with the scientific method, including full disclosure of methods, data, and other reliable information, conclusions that are consistent with the evidence, valid and simple methods, and valid and reliable data.

According to Armstrong, very little of the forecasting in climate change debate adheres to these criteria. “For example, for disclosure, we were working on polar bear [population] forecasts, and we were asked to review the government’s polar bear forecast. We asked, ‘could you send us the data’ and they said ‘No’… So we had to do it without knowing what the data were.”

According to Armstrong, forecasts from the Intergovernmental Panel on Climate Change (IPCC) violate all eight criteria.

“Why is this all happening? Nobody asks them!” said Armstrong, who says that people who submit papers to journals are not required to follow the scientific method. “You send something to a journal and they don’t tell you what you have to do. They don’t say ‘here’s what science is, here’s how to do it.’”

Worse, the research found that many results came not from data but to confirm something that was politically advantageous or helpful in winning grants.

Digging deeper into their motivations, Armstrong pointed to the wealth of incentives for publishing papers with politically convenient rather than scientific conclusions. “They’re rewarded for doing non-scientific research. One of my favourite examples is testing statistical significance – that’s invalid. It’s been over 100 years we’ve been fighting the fight against that. Even its inventor thought it wasn’t going to amount to anything. You can be rewarded then, for following an invalid [method].”

“They cheat. If you don’t get statistically significant results, then you throw out variables, add variables, [and] eventually you get what you want.” [emphasis mine]

The scientific community and especially the climate field has got to get a handle on this and demand better. Otherwise, we lose the greatest gift science has given to civilization, an unwavering dedication to the truth.

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ESA narrows landing site choice for ExoMars 2020 to two

10:02 pm

The European Space Agency has narrowed its choice of landing sites for its ExoMars 2020 rover mission.

Two ancient sites on Mars that hosted an abundance of water in the planet’s early history have been recommended as the final candidates for the landing site of the 2020 ExoMars rover and surface science platform: Oxia Planum and Mawrth Vallis.

A primary technical constraint is that the landing site be at a suitably low level, so that there is sufficient atmosphere to help slow the landing module’s parachute descent. Then, the 120 x 19 km landing ellipse should not contain features that could endanger the landing, the deployment of the surface platform ramps for the rover to exit, and driving of the rover. This means scrutinising the region for steep slopes, loose material and large rocks.

Oxia Planum was selected in 2015 for further detailed evaluation. Although not yet complete, the investigation so far indicates that the region would meet the various constraints.

They will spend the next year evaluating both sites, though based on the press release it sounds as if Oxia Planum is the favorite.

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Science discovers that cats prefer human companionship over food

10:29 am

News you can use: A new study has found that cats will choose human companionship over food if given a choice.

The researchers took 50 cats from shelters and peoples homes and deprived them of food, human contact, scent and toys for a few hours. They then introduced them to stimuli within these four categories to see what they chose.

Most cats chose human socialisation over any of the other categories.

From my perspective, what is even more important is that cats don’t choose those humans nonchalantly. Every cat lover knows that, unlike dogs, cats pick carefully whom they will love. But if they love you they show it.

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The longest stretch of no sunspots since 2009

10:45 am

The Sun just completed its longest stretch, 15 days, without sunspots since 2009, suggesting once again that the solar minimum is coming much sooner than expected.

So far this year the Sun has been blank 34% of the time, a pace that makes this year almost as blank as 2009, the year in which the previous solar minimum ended. This suggests that 2017 might be the year in which the next solar minimum begins, which would be about two years earlier than the earliest predictions.

The more likely scenario is that 2018 will be the year the solar minimum begins, with 2019 when solar activity bottoms out. This will still be much earlier than expected, making this solar cycle only about 9-10 years long. What makes this more significant is that historically short cycles always went with high activity, while long cycles signaled an inactive and weak maximum. This cycle will be the first that is both short and weak.

What happens next remains the big question. Will the Sun enter a grand minimum, with no sunspots for decades? Or will sunspot activity continue? Since solar scientists really do not yet understand the mechanism within the sun’s magnetic field that causes this solar cycle, we really can’t answer these questions, in advance. We must wait, and see.

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The changes seen by Rosetta on Comet 67P/C-G

1:51 pm

A new study released today describes in detail the many changes seen by scientists in the data collected by Rosetta during its two years in close proximity to Comet 67P/C-G.

“We saw a massive cliff collapse and a large crack in the neck of the comet get bigger and bigger,” said El-Maarry. “And we discovered that boulders the size of a large truck could be moved across the comet’s surface a distance as long as one-and-a-half football fields.”

In the case of the boulder, Rosetta’s cameras observed a 282-million-pound (130-million-kilogram), 100-feet-wide (30-meter) space rock to have moved 150 yards (460 feet, or 140 meters) from its original position on the comet’s nucleus. The massive space rock probably moved as a result of several outburst events that were detected close to its original position.

The warming of 67P also caused the comet’s rotation rate to speed up. The comet’s increasing spin rate in the lead-up to perihelion is thought to be responsible for a 1,600-foot-long (500-meters) fracture spotted in August 2014 that runs through the comet’s neck. The fracture, which originally extended a bit longer than the Empire State Building is high, was found to have increased in width by about 100 feet (30 meters) by December 2014. Furthermore, in images taken in June 2016, a new 500- to 1,000-foot-long (150 to 300 meters) fracture was identified parallel to the original fracture.

“The large crack was in the ‘neck’ of the comet — a small central part that connects the two lobes,” said El-Maarry. “The crack was extending–indicating that the comet may split up one day.”

It is almost a shame that Rosetta did not see that break-up. The images would have been breath-taking, and the science learned priceless.

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The rings of Saturn

9:38 am

The rings of Saturn up close

Cool image time! The image to the right, cropped to post here, is part of one of the closest and highest resolution images that Cassini has yet taken of Saturn’s rings. The image was taken in January during one of the spacecraft’s ring grazing orbits, and has a resolution of 2,300 feet per pixel. And yet, as noted by the Cassini science team, “Even at this level of detail, it is still not fine enough to resolve the individual particles that make up the ring.”

In prepping the image, all I did was crop it to show the closest rings. I purposely did not reduce its resolution, so that you can see that no individual particles are visible. The rings of Saturn are truly made up of billions of small objects, behaving in many ways like liquid floating in the gravity well of Saturn. If you don’t believe me, download the full image and zoom in on it as much as you like. All you will see are pixels.

The fundamental science question therefore is not how Saturn’s rings behave (though this is certainly important and quite fascinating) but why did those rings end up the way they are. No other planet has rings anything like Saturn’s in their density and make-up. Why? Are Saturn’s rings a normal process that only occurs for short times around planets, which is why only Saturn has these types of rings at present? Or is it a rare event, so rare that we happen to be very lucky to see such a thing at all?

Even more important, Saturn’s rings and their behavior are likely linked closely to the same phenomenon that describe the formation of planets around a star. The more we can learn about why these rings exist, the more we will learn about why planets exist, both here circling the Sun as well as around stars everywhere else.

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The layered mesas of Mars

12:06 pm

The mesas of Uzboi Valles

Cool image time! The image above, reduced and cropped to post here, shows the layered deposits and complex erosion that has taken place in this area of Mars dubbed Uzboi Vallis. As noted at the Mars Reconnaissance Orbiter post,

Layered deposits in Uzboi Vallis sometimes occur in alcoves along the valley and/or below where tributaries enter it. These deposits may record deposition into a large lake that once filled Uzboi Vallis when it was temporarily dammed at its northern end by the rim of Holden Crater and before it was overtopped and breached allowing water to drain back out of the valley.

It is important when looking at these erosion patterns, including the strangely shaped rippled sand dunes scattered through the larger image, that wind possibly plays an even more important part in causing erosion on Mars than liquid water might have in the far past.

Either way, the terrain here has the same stark and fascinating beauty as that seen in the American southwest. If we can ever make it possible to live on Mars, this will definitely be a place to visit when on vacation.

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Trump budget proposal

11:24 am

The Trump administration today released its overall rough budget plan for 2018. This is not a detailed budget, but an summary of their plan, indicating where they wish to cut and where they wish to increase budgets. The proposal is also not complete, making no mention of the administration’s budget plans for many departments, such as the National Science Foundation.

Science research in the federal government is significantly impacted, but not as badly as most of the articles you will read in the mainstream anti-Trump, Democratic Party press. A few examples:

I must note that not all the news stories are blindly hostile to this budget proposal:

Of all the science agencies, NASA probably came off with the least change. The budget cuts only about 5% from the agency’s Earth science budget, while cutting some specific Earth science missions. The budget also supports SLS/Orion, though it finally puts the nail in the coffin of the asteroid redirect mission, an Obama proposal that has never garnered any interest from anyone else.

The Trump budget proposal in context

The key to understanding all these budget cuts is to see them in context, to compare the 2018 proposed budgets with the budgets these agencies received in the past. The table on the right gives some of this context (numbers shown are in millions) for several of the science agencies most effected by the proposal. The proposal is not detailed enough to pin down the changes for many other science agencies, but from this table it is clear that the Trump administration is not calling for the end of science, and is proposing some reasonable cost cutting, something that has been rare in government for many years.

What will be missed by most of the press about this Trump budget proposal is that it is not trying to trim the size of the federal government. While it cuts spending in many departments, those cuts are entirely aimed at providing room to raise the budget of the Defense Department by $54 billion. While I can applaud the desire of the Trump administration to be revenue neutral, the stark fact remains that by remaining revenue neutral Trump still leaves us with a gigantic annual federal deficit. They have made no effort to balance the overall budget.

Worse, this proposal would repeal the Budget Control Act of 2011, which imposed sequestration to the federal budget and has actually done the most in the past half century to bring that budget under control. Once this act is repealed, it will allow the spenders in Congress (of which the Republicans are as guilty as the Democrats) to open the floodgates once again. This will not be good.

Let me add one good aspect of the Trump budget. It proposes to eliminate a whole range of government political agencies that accomplish nothing but provide pork or to propagandize the Democratic Party’s positions:

The Budget also proposes to eliminate funding for other independent agencies, including: the African Development Foundation; the Appalachian Regional Commission; the Chemical Safety Board; the Corporation for National and Community Service; the Corporation for Public Broadcasting; the Delta Regional Authority; the Denali Commission; the Institute of Museum and Library Services; the Inter-American Foundation; the U.S. Trade and Development Agency; the Legal Services Corporation; the National Endowment for the Arts; the National Endowment for the Humanities; the Neighborhood Reinvestment Corporation; the Northern Border Regional Commission; the Overseas Private Investment Corporation; the United States Institute of Peace; the United States Interagency Council on Homelessness; and the Woodrow Wilson International Center for Scholars.

Getting these eliminated will at least be a start to cleaning up the mess in Washington.

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Want to watch a nuclear bomb go off? You can!

9:49 am

Engineers at Lawrence Livermore National Laboratory (LLNL) have obtained declassified films of many of the nuclear tests performed by the U.S. from 1945 to 1962 and are digitally scanning them and preserving them for posterity.

Conducted by LLNL weapon physicist Greg Spriggs and a team of film experts, archivists, and software developers, the project’s goal was to track down as many as possible of the ten-thousand 2,400 frames per second reels of film. This was because the cine film, and its immense historical and scientific value, was in danger of being lost for all time. The reels were mostly of acetate stock that was not stored under anything like ideal conditions and was slowly decaying or being attacked by fungus and microbes.

“You can smell vinegar when you open the cans, which is one of the byproducts of the decomposition process of these films,” says Spriggs. “We know that these films are on the brink of decomposing to the point where they’ll become useless. The data that we’re collecting now must be preserved in a digital form because no matter how well you treat the films, no matter how well you preserve or store them, they will decompose. They’re made out of organic material, and organic material decomposes. So this is it. We got to this project just in time to save the data.”

You can view a number of the films at the second link above. I have embedded below the fold just one, from Operation Teapot in 1955. This was a series of 14 tests in Nevada. In this particular video the explosion occurs in the air, and you can sense the incredible force of the explosion when the shock wave hits the ground and bounces back, producing the mushroom cloud. Not much would have survived that impact.
» Read more

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Less evidence of dark matter in early universe

10:49 pm

The uncertainty of science: Astronomers have discovered less evidence of dark matter surrounding galaxies in early universe.

Stars in the outer regions of some far-off galaxies move more slowly than stars closer to the center, indicating a lack of dark matter, astronomer Reinhard Genzel and colleagues report online March 15 in Nature. If confirmed, the result could lead astronomers to reconsider the role dark matter played in early galaxy evolution and might also offer clues to how nearby elliptical galaxies evolved.

In contrast with these distant galaxies, stars orbiting on the outskirts of the Milky Way and other nearby galaxies move too fast for their velocities to result only from the gravity of gas and stars closer to the galactic center. If visible galactic matter is embedded in a cloud of invisible dark matter, though, gravity from the invisible matter can explain the high stellar velocities. Using stars’ orbital velocities in nearby galaxies as a reference, astronomers expected that stars in galaxies farther away would behave similarly. “Turns out that is not the case,” says study coauthor Stijn Wuyts of the University of Bath in England.

In other words, scientists at this moment really have no idea what causes the faster rotation in the outskirts of modern nearby galaxies.

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Titan’s fizzy oceans?

11:36 am

New research suggests that the hydrocarbon lakes of Titan might periodically fizz with nitrogen bubbles.

A recent NASA-funded study has shown how the hydrocarbon lakes and seas of Saturn’s moon Titan might occasionally erupt with dramatic patches of bubbles.

For the study, researchers at NASA’s Jet Propulsion Laboratory in Pasadena, California, simulated the frigid surface conditions on Titan, finding that significant amounts of nitrogen can be dissolved in the extremely cold liquid methane that rains from the skies and collects in rivers, lakes and seas. They demonstrated that slight changes in temperature, air pressure or composition can cause the nitrogen to rapidly separate out of solution, like the fizz that results when opening a bottle of carbonated soda.

These results might help explain the mysterious islands that seem to appear and disappear and then reappear in Titan’s lakes. Rather than islands, they might be patches of nitrogen bubbles.

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