Year: 2012

New close-up photos of the asteroid Vesta from Dawn have discovered numerous bright spots scattered across the face of the asteroid Vesta.

9:07 pm

New close-up photos of the asteroid Vesta from Dawn have discovered numerous bright spots scattered across the face of the asteroid Vesta.

The photos show surprisingly bright spots all over Vesta, with the most predominant ones located inside or around the asteroid’s many craters. The bright areas range from large spots (around several hundred feet across) to simply huge, with some stretching across 10 miles (16 kilometers) of terrain.

The scientists believe the bright spots might be the asteroid’s oldest material, excavated from below by impacts.

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After one year in orbit around Mercury, Messenger’s scientists have concluded that Mercury is not only dense but odd.

4:35 pm

After one year in orbit around Mercury, Messenger’s scientists have concluded that Mercury is not only dense but odd.

The [proposed gravity] model, when combined with topography data and measurements of the planet’s spin, reveals that as much as 85% of Mercury’s radius is taken up by its dense iron core — an upward revision. “We knew Mercury had a large core,” says [Maria Zuber of MIT]. “Now we think it’s even larger.” What’s more, to compensate for a crust that’s enriched in sulphur and depleted in iron, the team has proposed a solid shell of iron sulphide that sits between the core and the mantle. While the shell satisfies the gravity constraints, it also makes it more difficult for a lot of convection to occur in the thin mantle that overrides it — which presents problems for those that invoke convection as a driver of the observed tectonic and volcanic features at the surface. “There isn’t a whole lot of mantle to be doing this lifting up,” says Zuber.

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Cat purrs prevent heart attacks

7:08 am

Research has now shown that the purr of a cat appears to prevent heart attacks.

A 10-year study at the University of Minnesota Stroke Center found that cat owners were 40 per cent less likely to have heart attacks than non-cat owners. A cat at home reduced the risk of other heart diseases and stroke by 30 per cent.

But then, all cat owners have always known this.

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