* Astronomy

OPPORTUNITY UPDATE:  Circling the Meteorite - sols 1995-2000, September 03-08, 2009:
Opportunity has commenced circumnavigation and full-circle imaging of the large meteorite "Block Island".

On Sol 1995: (Sept. 3, 2009), a solar-array dust-cleaning event occurred.
As of Sol 2000 (Sept. 8, 2009), Opportunity's solar-array energy production is 527 watt-hours, with an atmospheric opacity (tau) of 0.475 and a dust factor improved to 0.6145. The rover's total odometry is 17,238.97 metres.
On Sol 1997: (Sept. 5, 2009), the rover moved 5.7 metres to the second of six stand-off positions around the meteorite (the first position being the initial rover location). At each location Opportunity collects a set of images with the panoramic camera (Pancam).
On Sol 1999: (Sept. 7, 2009), Opportunity drove about 4 metres to the third position. The plan is to complete the circumnavigation of the meteorite before departing this location.

'Crazy quilt' of moves may free stuck Mars rover
After a month of spinning their wheels in a sandbox, NASA engineers have settled on a strategy to free the rover Spirit from a sand trap on Mars: just wing it.
The geriatric rover slid into soft terrain in early May, burying its wheels halfway into the flour-like soil. To test strategies for getting out without risking a catastrophic misstep, engineers rolled a duplicate rover into a sandbox at NASA's Jet Propulsion Lab in Pasadena, California, that mimics the Martian morass.

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NASA's Opportunity rover has discovered what appears to be the largest meteorite ever found on Mars. Dubbed 'Block Island' the rock measures 60 cm across.
Opportunity first stumbled across the rock on 18 July, before snapping pictures to send to Earth and motoring calmly on.

"The images came down after we had already passed" - planetary scientist Albert Yen of NASA's Jet Propulsion Laboratory in Pasadena, California.

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From views of spectacularly layered cliff walls and sulphate-rich rock to the detection of tiny hematite "blueberries" and probable meteor debris, the Mars rover Opportunity's two-year exploration of Victoria Crater has yielded a wealth of information about the planet's geologic history -- and supported previous findings indicating that water once flowed on the planet's surface.
As Opportunity heads south toward Endeavor Crater, 13.5 kilometres away, a paper in the May 22 issue of the journal Science reports on the major findings from Victoria. The giant impact crater -- 750 metres wide and 75 metres deep -- gave scientists an unparalleled view into the planet's evolution, revealing evidence of a windy, wet and dynamic past.
The paper is a broad summary of observations that were released incrementally as they were made over the last two years, said Steve Squyres, principal investigator for NASA's Mars Exploration Rover mission and Cornell's Goldwin Smith Professor of Astronomy.
Many of those observations -- of hematite spheres (the blueberries), sulphate-rich sandstone and small chunks of rock containing kamacite, troilite and other minerals commonly found in meteorites -- are consistent with Opportunity's findings across Meridiani Planum, the rocky plateau the size of Oklahoma where the rover landed Jan. 24, 2004.

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