Posts Tagged ‘Mars’
2009
“The Opportunity rover has come across an odd-shaped, large, dark rock, about 0.6 meters (2 feet) across on the surface of Mars, which may be a meteorite. The rover team spotted the rock called “Block Island,” on July 18, 2009, in the opposite direction from which it was driving. The team then had the rover do a hard right (not really, but you know what I mean) and backtrack some 250 meters (820 feet) to study it closer. Oppy has been studying the rock with its alpha particle X-ray spectrometer to get composition measurements and to confirm if indeed it is a meteorite…
Block Island really does have a meteorite-like look to it. Stu suggested on his blog that it looks like several meteorites found on Earth, such as one of the Derrick Peak meteorites found in Antarctica, shown below. The Derrick Peak meteorites are iron meteorites, and about 27 were found in one location in Antarctica. Researchers believe they all came from one meteor shower…”
source universetoday.com
“There’s a growing chorus of calls to send astronauts to Mars rather than the moon, but critics point out that such trips would be long and gruelling, taking about six months to reach the Red Planet. But now, researchers are testing a powerful new ion engine that could one day shorten the journey to just 39 days.
Traditional rockets burn chemical fuel to produce thrust. Most of that fuel is used up in the initial push off the Earth’s surface, so the rockets tend to coast most of the time they’re in space.
Ion engines, on the other hand, accelerate electrically charged atoms, or ions, through an electric field, thereby pushing the spacecraft in the opposite direction. They provide much less thrust at a given moment than do chemical rockets, which means they can’t break free of the Earth’s gravity on their own.
But once in space, they can give a continuous push for years, like a steady breeze at the back of a sailboat, accelerating gradually until they’re moving faster than chemical rockets.
Several space missions have already used ion engines, including NASA’s Dawn spacecraft, which is en route to the asteroids Vesta and CeresMovie Camera, and Japan’s spacecraft Hayabusa, which rendezvoused with the asteroid Itokawa in 2005.”
source: newscientist.com