science – Page 163 – Behind The Black

Images of Ceres from Dawn’s lowest orbit

December 22, 2015 10:40 am Robert Zimmerman

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

December 21, 2015 9:51 pm Robert Zimmerman

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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Strong academic objections to unopposed election for National Academies president

December 21, 2015 5:49 pm Robert Zimmerman

The president of the National Association of Scholars has written a scathing letter to the National Academy of Sciences condemning the unopposed candidacy of Dr. Marcia K. McNutt, the present editor-in-chief of the journal Science, as president of the Academy.

Their complaint has to do with her policy at Science of censoring any dissenting opinions on a number of science subjects, including climate change.

Science [the journal] promotes the so-called consensus model of climate change and excludes any contrary views. This issue has become so polarized and polarizing that it is difficult to bring up, but at some point the scientific community will have to reckon with the dramatic discrepancies between current climate models and substantial parts of the empirical record. Recent evidence of Science bias on this issue is the June 26, 2015 article by Dr. Thomas R. Karl, “Possible artifacts of data biases in the recent global surface warming hiatus”; the July 3, 2015 McNutt editorial, “The beyond-two-degree inferno”; the November 13, 2015 McNutt editorial, “Climate warning, 50 years later”; and the November 25, 2015 AAAS News Release, “AAAS Leads Coalition to Protest Climate Science Inquiry.”

Dr. McNutt’s position is, of course, consistent with the official position of the AAAS. But the attempt to declare that the “pause” in global warming was an illusion has not been accepted by several respected and well-informed scientists. One would not know this, however, from reading Science, which has declined to publish any dissenting views. One can be a strong supporter of the consensus model and yet be disturbed by the role which Science has played in this controversy. Dr. McNutt and the journal have acted more like partisan activists than like responsible stewards of scientific standards confronted with contentious claims and ambiguous evidence. The relevant documents and commentary regarding the Karl paper and McNutt editorials can be examined at https://www.nas.org/images/documents/Climate_Change.pdf. [emphasis mine]

The letter outlines two other areas where McNutt has appeared to play favorites in areas of scientific controversy, and thus questions the wisdom of allowing her to run unopposed for presidency of the National Academy of Sciences.

What is important about this letter is that indicates that there is an increasing pushback from scientists against the demands of orthodoxy. Rather than going along with the powers-that-be, the National Association of Scholars is stating its increasing distrust of the scientific integrity of those powers.

Posted from Sedona, Arizona.

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Astronomers successfully predict appearance of supernova

December 16, 2015 11:35 pm Robert Zimmerman

For the first time ever astronomers have been able to predict and photograph the appearance of a supernova, its light focused by the gravitational lensing caused by a galaxy and the dark matter that surrounds it.

The NASA/ESA Hubble Space Telescope has captured the image of the first-ever predicted supernova explosion. The reappearance of the Refsdal supernova was calculated from different models of the galaxy cluster whose immense gravity is warping the supernova’s light.

What makes this significant is that the prediction models were based on the theory of gravitational lensing and required the presence of dark matter to work. That they worked and were successful in predicting the appearance of this gravitationally bent light (bent by the dark matter it passed through) is a very strong confirmation of both concepts. Up until now I have been somewhat skeptical of gravitational lensing. This confirmation removes some of that skepticism.

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Hype in science papers on the increase

December 15, 2015 9:19 am Robert Zimmerman

In the past forty years the use by scientists of descriptive words to positively hype their results in their papers has increased steadily.

Researchers at the University Medical Center Utrecht in the Netherlands say that the frequency of positive-sounding words such as ‘novel’, ‘amazing’, ‘innovative’ and ‘unprecedented’ has increased almost nine-fold in the titles and abstracts of papers published between 1974 and 2014. There has also been a smaller — yet still statistically significant — rise in the frequency of negative words, such as ‘disappointing’ and ‘pessimistic’.

…The most obvious interpretation of the results is that they reflect an increase in hype and exaggeration, rather than a real improvement in the incidence or quality of discoveries, says Vinkers. The findings “fit our own observations that in order to get published, you need to emphasize what is special and unique about your study,” he says. Researchers may be tempted to make their findings stand out from thousands of others — a tendency that might also explain the more modest rise in usage of negative words.

The word ‘novel’ now appears in more than 7% of PubMed paper titles and abstracts, and the researchers jokingly extrapolate that, on the basis of its past rise, it is set to appear in every paper by the year 2123.

This study was focused on the medical field, so it is unclear if its results could be extrapolated to other science fields. I suspect it can.

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Rosetta hi-res images released

December 15, 2015 8:41 am Robert Zimmerman

Lots of cool images! The science team running Rosetta’s high resolution camera have finally made available to the public the camera’s large archive of images.

The images cover the period 20 June 2014 – 16 September 2014, corresponding to Rosetta’s approach to the comet, arrival, and insertion into orbit.

In exchange for creating and running the mission, the scientists had been given a 12 month period in which these hi-res images belonged entirely to them. This gave them the chance to use them to publish papers documenting their discoveries. While this is a reasonable arrangement — used by most planetary missions in some manner to reward the scientists who made the mission possible — with Rosetta the hi-res images were kept so close to the vest that practically none have been seen, until now. Moreover, this release is very late, anywhere from 15 to 18 months after the images were taken, not 12.

Most other planetary missions make sure that at least some images are released as the mission proceeds, since the images were paid for by the public. The European Space Agency should take a look at its future policies for publicly-funded missions to make sure the public gets better access in the future.