USGS Astrogeology Hot Topics

Mars Express Pictures

Tuesday, June 29, 2004

Melas Chasma Steep cliffs drop into the rugged terrain of Melas Chasma in this stunning view from the Mars Express spacecraft orbiting the Red Planet.

Mars Express, DLR, ESA

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Mars Express, the first European Space Agency probe to head for another planet entered orbit around Mars, from where it performs detailed studies of the planet's surface, its subsurface structures and its atmosphere. shown here is a picture the Mars Express took of the Melas Chasma.

More: G. Neukum (FU Berlin) et al., Mars Express, DLR, ESA - Mars Express Image

Link: JPL - Mars Express en route for the Red Planet

Link: ESA - Mars Express Home

Posted by HotTopics in Mars Express at 18:42

Mars Rover Surprises Continue; Spirit, Too, Finds Hematite

Friday, June 25, 2004

This close-up image taken by Spirit highlights the nodular nuggets that cover the rock dubbed "Pot of Gold."

NASA/Cornell/USGS

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Spirit rolled up to a knobby rock just past where the "Columbia Hills" start to rise from the surrounding plain. It touched the rock with a mineral-identifying instrument at the tip of its robotic arm and detected hematite. Hematite identified from orbit was NASA's key reason for choosing Opportunity's landing site halfway around Mars from these hills within Gusev Crater.

More: JPL - Mars Rover Surprises Continue; Spirit, Too, Finds Hematite

Link: Cornell University - Mars Rover Mission Journal

Posted by BlogAdmin in MER at 19:04

Spirit Reaches Columbia Hills

Wednesday, June 16, 2004

On sol 156, Spirit roved 42 meters (138 feet) closer to a vantage point where it could observe the hill outcrops. Some of the images that Spirit sent back revealed a small and unusual rock that piqued scientists' interest and was informally named "End-of-Rainbow." Part of the sol 157 plan was to observe End-of-Rainbow and use the alpha particle X-ray spectrometer, Mössbauer spectrometer and microscopic imager to study the "Shredded" soil target. However, the command load for sol 157 never made it to Spirit. Further analysis indicated that the problem had to do with the frequency drift associated with the colder temperatures on Mars as the planet moves into its southern winter season. This was an anticipated problem, and the rover team has already imposed some strategies that will help to prevent the problem in the future.

More: NASA - Spirit Reaches 'Columbia Hills'

Posted by HotTopics at 19:07

Transit of Venus

Tuesday, June 8, 2004

Transits of Venus across the disk of the Sun are among the rarest of planetary alignments. Indeed, only six such events have occurred since the invention of the telescope (1631, 1639, 1761, 1769, 1874 and 1882). Two transits of Venus are occuring within a few years of eachother - the first was on June 08, 2004, the next will be June 06, 2012. Transits of Venus are only possible during early December and early June when Venus's orbital nodes pass across the Sun. If Venus reaches inferior conjunction at this time, a transit will occur. Transits show a clear pattern of recurrence at intervals of 8, 121.5, 8 and 105.5 years. The next pair of Venus transits occur over a century from now on 2117 Dec 11 and 2125 Dec 08.

More: NASA Sun-Earth - Venus Transit 2004

More: Science@NASA - James Cook and the Transit of Venus

More: Space Weather - Transit of Venus Photo Gallery

Posted by HotTopics in Sky Watching at 12:00