Author: Robert Zimmerman

Sand dunes and dry ice on Mars

12:07 pm

Time for some more sightseeing on Mars. A recent news release from Mars Reconnaissance Orbiter noted the discovery of seasonal avalanches on Mars. This new image of the northern martian sand dunes illustrate again how the surface of Mars changes seasonally. The white patches on the ridges of the sand dunes is frozen carbon dioxide, dry ice that condenses on the crowns of the dunes every winter. When spring comes, the dry ice evaporates, and as it does so it disturbs the underlying sand, which then tumbles down the sides of the dunes, producing the dark streaks.

Ice-capped sand dunes

The process is less dramatic, however, than the avalanches seen in the previous news release, as suggested by this image below, showing the same dunes in summer without the dry ice. The dark streaks in the second image are not significantly different from the first, indicating that the process that forms them is slow and subtle.

Sand dunes with ice-cap

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NBC employee who distributed “What is the internet?” video fired

12:04 am

The NBC employee who distributed the “What is the internet?” video was fired this week for doing so. First, if you haven’t seen it, here’s the video:

Though this video is hilarious, and does illustrate how completely contemptuous TV news anchors can be about new things they haven’t bothered to do any research about, it is also unfair to laugh at them with 20-20 hindsight. At one point or another we were all as ignorant as they are. Note also that we do not know the whole story about why NBC fired this employee.

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Falcon 9 signed to launch Google Lunar X prize competitor

10:33 am

One of the competitor’s for the Google Lunar X prize has signed a contract with SpaceX to use the Falcon 9 to get its spacecraft to the Moon. Key quote:

The Falcon 9 upper stage will sling Astrobotic on a four-day cruise to the Moon. Astrobotic will then orbit the moon to align for landing. The spacecraft will land softly, precisely and safely using technologies pioneered by Carnegie Mellon University for guiding autonomous cars. The rover will explore for three months, operate continuously during the lunar days, and hibernate through the lunar nights. The lander will sustain payload operations with generous power and communications.

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Bernanke headlines a day of grim warnings about the nation’s fiscal standing

12:24 pm

Fed chairman Bernanke issued a grim warning yesterday about the federal government’s overwhelming debt. Key quote:

The national debt is currently about 60 percent of the economy, or Gross Domestic Product, [Bernanke] said, adding that it is projected to reach 90 percent of GDP by 2020 and 150 percent of GDP by 2030. But Bernanke’s citation of $9.5 trillion in national debt didn’t include the $4.6 trillion owed by the government to trust funds for things such as Social Security and Medicare, which have paid out cash to the Treasury in exchange for promisory notes. The full national debt – when both forms of debt are included – is already just under 100 percent of GDP, which is currently around $14.6 trillion.

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Scientists discover treasure trove of fossils in limestone layer in China

4:53 pm

Scientists have discovered a treasure trove of 250-million-year-old fossils in limestone layer in China. Key quote:

The 50-foot-thick (16 meters) layer of limestone that held these fossils dates back to when south China was a large island just north of the equator with a tropical climate. A smattering of fossil land plants suggest this marine community lived near a conifer forest. The fossils are exceptionally well-preserved, with more than half of them completely intact, including soft tissues. Apparently they were protected across the ages by mats of microbes that rapidly sealed their bodies off from decay after death.

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