This image of "Block Island" was taken on July 28, 2009, with the front hazard-identification camera on NASA's Mars Exploration Rover Opportunity. The Opportunity rover has eyed an odd-shaped, dark rock, about 0.6 meters (2 feet) across on the surface of Mars, which may be a meteorite. The team spotted the rock called "Block Island," on July 18, 2009, in the opposite direction from which it was driving. The rover then backtracked some 250 meters (820 feet) to study it closer. Scientists will be testing the rock with the alpha particle X-ray spectrometer to get composition measurements and to confirm if indeed it is a meteorite.

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The top exterior of Space Shuttle Endeavour's crew cabin, along with the International Space Station's Kibo laboratory and Harmony node are featured in this image photographed by a STS-127 crew member during the mission's second session of extravehicular activity (EVA) on 20 July 2009. high res (1.2 M) low res (88 K)

Jagged looking shadows stretch away from vertical structures of ring material created by the moon Daphnis in this image [Full-Res: PIA11547] taken as Saturn approaches its August 2009 equinox.

Mount Tambora Volcano, Sumbawa Island in Indonesia is featured in this image photographed by an Expedition 20 crew member on the International Space Station. On April 10, 1815 the Tambora volcano produced the largest eruption in history. An estimated 150 cubic kilometers of tephra -- exploded rock and ash -- was produced, with ash from the eruption recognized at least 1,300 kilometers away to the northwest.

Novaya Zemlya [Larger image] is an Arctic archipelago off the coast of the Russian Federation. Besides several smaller isles, Novaya Zemlya consists of two major islands, Severny in the north and Yuzhny in the south, separated by a narrow strait, Matochkin Shar. An extension of the Ural Mountains, this mountainous archipelago has an average altitude of roughly 1,000 meters (3,280 feet) above sea level, and glaciers cover much of the northern island. In the latter half of the twentieth century, Novaya Zemlya was used as a nuclear test site.

Image: Avatars in a virtual amphitheatre watch and listen to a graduate student presentation streamed from AbGradCon into Second Life.

Weary of catching planes, burning up fossil fuels, and spending lots of time and money to attend meetings? Take heart! Virtual worlds are shaping up as possible venues for online meetings--and astrobiology graduate students are leading the way in exploring their potential.