Bad Astronomy

Two planets, no waiting

The Mars Reconnaissance Orbiter is starting to send ‘em back now. The image above is a 1/2 res crop of a 3000x2300 image of the martian surface– click it for the page with the full-res version.

Here is the bigger of those three craters at full res (though slightly JPG compressed– don’t tell Hoagland or he’ll claim he sees the London Symphony Orchestra there):

It looks like there is rubble and dust in the crater floor, no doubt sculpted by a billion years of thin but high-speed winds. Unfortunately, I could not find a scale for this image, so I don’t know how big the crater is.

Not only that, but Venus Express has already switched on its cameras, and delivered this interesting snapshot:

That spectacular image was taken over Venus’s south pole. The left hand side is the daylight half, and is a composite of visible and UV filters. The right hand side is the night side, and is in infrared with false colors. Where the image is dark, the clouds are thick, blocking the heat of the surface from escaping. Where it’s bright, the clouds are higher and thinner, allowing some of the IR to escape to space. You are seeing Venus’s runaway greenhouse effect in action in this image.

This image was taken when VE was still about 200,000 miles above the surface of Venus– roughly the distance of the Moon from the Earth.

Expect a lot more cool stuff from these orbiters as time goes on.’