Catching an avalanche on Mars, as it happens

The Mars Reconnaissance Orbiter team today released this really cool image from Mars, showing an avalanche near the North Pole, in progress. The image looks directly down the cliff face from above. At the base of the cliff we can see the dust cloud from the crash of material billowing out away from the scarp.

What impresses me most about this image is that it was taken by an orbiting spacecraft approximately 200 miles above the planet’s surface, moving at thousands of miles an hour. Yet, the camera not only had the resolution to see the cloud of dust, it could snap the image fast enough to capture the actual fall of material (the white wisps down the side of the cliff that are reminiscent of a waterfall).

Also intriguing is the visible steep face of the cliff face itself. I know a lot of rock climbers who would love to literally get their hands (and chocks) on that rock face. And in Mars’s one-third gravity, rock climbing would surely be different.

avalanche on Mars

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The cause of white nose, the killer of bats

Scientists today confirmed that the fungus, Geomyces destructans, causes white nose syndrome, the deadly killer that has been wiping out cave-hibernating bats throughout the eastern United States.

A science team led by David Blehert of the National Wildlife Health Center in Madison, Wisconsin captured healthy little brown bats and infected them with the fungus while they were in hibernation, some by direct application and others by putting them in contact with already infected bats. After 102 days, all of the first group had developed white nose on their muzzles and wings, while 16 of 18 of the second group had become infected as well.
» Read more

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The battle in Congress of the EPA’s effort to regulate dust

The battle in Congress over the EPA’s effort to regulate dust.

Not surprisingly, the Democrats all support the EPA’s effort, while there are Republicans who oppose. What I consider significant is that more than a hundred agricultural organizations oppose the regulations.

One of the agricultural groups that is supporting the bill [to block the EPA regulations], the National Association of Wheat Growers (NAWG), wrote a letter to the committee last month, saying that a slight raise in overall particulate matter standards would require the EPA to regulate farm dirt under the current standards. β€œAnd, for what purpose? Scientific studies have never shown rural dust to be a health concern at ambient levels,” said the NAWG letter. [emphasis mine]

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Has dark matter been identified?

From a paper published today on the Los Alamos astro-ph preprint website, scientists suggest that three different physics experiments might have identified dark matter. From the abstract:

Three dark matter direct detection experiments (DAMA/LIBRA, CoGeNT, and CRESST-II) have each reported signals which are not consistent with known backgrounds, but resemble that predicted for a dark matter particle with a mass of roughly ~10 GeV. . . . In this article, we compare the signals of these experiments and discuss whether they can be explained by a single species of dark matter particle, without conflicting with the constraints of other experiments. We find that the spectrum of events reported by CoGeNT and CRESST-II are consistent with each other and with the constraints from CDMS-II, although some tension with xenon-based experiments remains. Similarly, the modulation signals reported by DAMA/LIBRA and CoGeNT appear to be compatible, although the corresponding amplitude of the observed modulations are a factor of at least a few higher than would be naively expected, based on the event spectra reported by CoGeNT and CRESST-II. This apparent discrepancy could potentially be resolved if tidal streams or other non-Maxwellian structures are present in the local distribution of dark matter.

The last sentence above suggests that the differences between the various experiments might be explained by the motion of dark matter itself as it flows through the solar system.

This conclusion is very tentative. The scientists admit that there remain conflicts between the results of the three experiments, and that there also could be explanations other than dark matter for the results. Furthermore, the results of other experiments raise questions about this conclusion.

Nonetheless, it appears that physicists might be closing in on this most ghostlike of all particles in the universe.

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Eradicating polio: not this year

The effort to eradicated polio entirely by the end of 2012 will not be met.

Afghanistan and Nigeria, two of the three remaining endemic countries, have had more cases in the first nine months of this year than in 2010 altogether. Several other countries targeted by the plan have also seen more cases to date this year compared to this time in 2010. Additionally, polio had popped up in countries where it had previously been eradicated β€” notably China, which went polio-free for 11 years until this summer.

Sadly, politics and culture are almost certainly the main reasons polio still survives in these countries.

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