The rover Opportunity as seen from Mars orbit

Opportunity on Endeavour Crater rim

The image to the right was taken by Mars Reconnaissance Orbiter, with the white arrow showing the Mars rover Opportunity perched on the rim of Endeavour Crater.

The rover’s scientists hope that the rocks found on the crater rim, dredged up from deep below when the crater impact occurred, will be the oldest rocks so far touched on the Martian surface, and thus give them a peek at ancient Martian geology.

Farmers flee as Indonesia’s Mount Tambora volcano rumbles

Farmers begin fleeing as Indonesia’s Mount Tambora volcano comes back alive.

Villagers like Hasanuddin Sanusi have heard since they were young how the mountain they call home once blew apart in the largest eruption ever recorded — an 1815 event widely forgotten outside their region — killing 90,000 people and blackening skies on the other side of the globe. . . . The April 1815 eruption of Tambora left a crater 7 miles (11 kilometers) wide and half a mile (1 kilometer) deep, spewing an estimated 400 million tons of sulfuric gases into the atmosphere and leading to “the year without summer” in the U.S. and Europe.

When dust, pebbles, rocks, and boulders act like liquid

The science team of Lunar Reconnaissance Orbiter released an intriguing picture yesterday of what scientists call a granular flow down the side of a five mile wide crater on the far side of the moon. Looking at the image, one would swear that the darker material flowing down the slope of the crater rim is a lava flow frozen in place.

lunar granular flow

However, according to the scientists, that is not what it is. Instead, this is merely debris left behind from an avalanche.
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Earthquake in Virginia

Quake map

A 5.9 magnitude earthquake hit Virginia at about 1:51 pm (Eastern).

I am in Maryland, just outside the beltway, and felt something like an earthquake about five minutes ago. The house started to shake, then settled, then shook again. Quite startling. I opened the front door the same time a neighbor did. She had felt the same thing.

The above quake was more than 90 miles away. I wonder how bad it is there, considering the eastern U.S. rarely experiences quakes and has made no preparations for such a thing.

For updates:
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Craters, craters, everywhere

Below the fold are two images released today, one from Dawn at Vesta and the other from Messenger at Mercury. What makes them interesting to me is that, though the surfaces of both Vesta and Mercury are crater-packed, there are definitely distinct differences between them that one can spot if you look closely, all highlighting the fundamentally different environments of both worlds.

First, the Vesta photograph. The image looks out past the asteroid’s horizon, showing clearly that this dwarf planet is not spherical, with the south pole depression that puzzles scientists just on the planet’s limb. The parallel long deep grooves that are associated with this depression can be seen on the right. Notice also that the inside walls of all the craters slope downward in a very shallow manner. This gives the impression that the impacts that formed these craters smashed into an almost beachlike sandy surface. Note too the that the center of some craters have what appear to be flat small “ponds,” a phenomenon seen by the spacecraft NEAR when it orbited the asteroid Eros. These ponds are not liquid, but are actually made up of fine-grained particles that settle in the hollows of the asteroid.
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Endeavour Crater at last!

The science team for the rover Opportunity have released their first image taken from the rim of Endeavour Crater.

Since this picture looks south from Spirit Point less than a football field’s distance from the rim, it appears to look into the crater, the mountains on the right being the crater’s rim. What looks like a debris field running across the center of the image looks to me to be a combination of exposed patches of bedrock and boulders on the plateau above the rim. For the scientists, those boulders will be the prime research targets, as they are possibly ejecta produced at crater impact and could therefore be material thrown out from deep within the Martian crust.

a view of Endeavour Crater

Nebraska rare earth mineral discovery to challenge China’s monopoly

A discovery in Nebraska of rare earth minerals appears set to challenge China’s monopoly.

To me these were the key quotes from this article:

The U.S. used to produce rare earths through the Mountain Pass Mine in California, but it was shut down in 2002, primarily because of environmental concerns, including the spillage of hundreds of thousands of gallons of water carrying radioactive waste into a nearby lake.

and

Although studies have shown the U.S. has 13 million metric tons of rare-earth minerals, National Mining Association spokeswoman Carol Raulston said it does not mine any of it – partly as a result of the difficulty of obtaining permits. “One of the key problems that investors tell us about is that the permitting regime in this country is so complicated and time-consuming that it has hurt investments here in the United States,” Ms. Raulston said.

Another Iceland volcano appears about to erupt

Another Iceland volcano, Hekla, is showing signs that it is about to erupt.

The volcano, dubbed by Icelanders in the Middle Ages as the “Gateway to Hell,” is one of Iceland’s most active, having erupted some 20 times over the past millennium, most recently on Feb. 26, 2000. It measures 4,891-feet (1,491-meters) and is located about 70 miles (110 kilometers) east of Reykjavik, not far from Eyjafjoell.

Scientists find previously unknown deposits of CO2 on Mars

Scientists find a gigantic and previously unknown deposit of CO2 at Mars’ south pole.

“We already knew there is a small perennial cap of carbon-dioxide ice on top of the water ice there, but this buried deposit has about 30 times more dry ice than previously estimated,” said Roger Phillips of Southwest Research Institute in Boulder, Colo. Phillips is deputy team leader for the Mars Reconnaissance Orbiter’s Shallow Radar instrument and lead author of the report. . . . “When you include this buried deposit, Martian carbon dioxide right now is roughly half frozen and half in the atmosphere, but at other times it can be nearly all frozen or nearly all in the atmosphere,” Phillips said.

What this discovery means is that, depending on Mars’ orbital circumstances, its atmosphere can sometimes be dense enough for liquid water to flow on its surface.

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