http://www.marsnews.com/ en-us tourdemars@marsnews.com Copyright 2012 Wed, 18 Jan 2012 11:20:37 -0800 Sun, 22 Jan 2012 14:15:00 -0800 http://www.movabletype.org/?v=3.2 tourdemars@marsnews.com 60 A meteorite that fell to Earth last July in Morocco has proven to be a rare chunk of Mars. Only a handful of Martian meteorites are known, and only five (counting the new find) come from meteorites whose fall was witnessed. That’s important because it tells scientists how long it has been lying on the ground, and therefore how much contamination it might have picked up. In this case, about a dozen pieces (such as the one shown, right), totalling several kilograms, were recovered from Morocco in late December. “Because it’s only been on the ground for six months or less, it hasn’t been exposed to much contamination,” says Chris Herd, a planetary geologist specializing in meteorites at the University of Alberta, Edmonton, Canada. Herd chairs an international meteoritics committee that yesterday certified the rocks as coming from Mars and approved their name – Tissint – in honour of the village near which they were found. http://www.marsnews.com/archives/2012/01/18/morocco_fireball_yields_rare_mars_meteorites.html Meteorites Wed, 18 Jan 2012 11:20:37 -0800 Arizona State University’s Center for Meteorite Studies has acquired a significant new sample for its collection, a rare martian meteorite that fell in southern Morocco in July 2011. It is the first martian fall in around fifty years. Since the observed fall of the famed Ensisheim meteorite in 1492, there have been around 1,200 recovered meteorite falls. A “fall” is a meteorite that was witnessed by someone as it fell from the sky, whereas a “find” is a meteorite that was not observed to fall but was later found and collected. Only a handful of witnessed meteorite falls occur each year. The chance of finding a meteorite is exceedingly small. The chance of witnessing a meteorite fall and finding it is even smaller – and the probability that the fall is a martian meteorite is smaller yet. http://www.marsnews.com/archives/2012/01/18/asus_center_for_meteorite_studies_acquires_exotic_piece_of_mars.html Meteorites Wed, 18 Jan 2012 11:20:37 -0800 Exactly a century ago, on June 28, 1911, an explosion shook the Nakhla region of Alexandria in Egypt at 9 a.m. Soon after, around 40 chunks of meteorite debris from the high altitude blast rained down. 22 pounds (10 kilograms) of the bolide were recovered by witnesses of this cosmic event. The Smithsonian received two samples of the Nakhla meteorite the following August and then acquired a larger 480 gram (one pound) piece in 1962 (pictured top). By the 1970's, the Smithsonian had collected 650 grams (1.4 pounds) of the meteorite. http://www.marsnews.com/archives/2011/06/28/100_years_ago_a_chunk_of_mars_hit_egypt_and_a_dog.html Meteorites Tue, 28 Jun 2011 18:07:00 -0800 The oldest known Martian meteorite – a space rock that fell to Earth – is some 400 million years younger than originally thought. It formed about 4.091 billion years ago, a time when the red planet was wet and had a magnetic field, a new study suggests. Studying this chunk of ancient Mars, which reflects the volcanic processes and bombardment by space debris, could help scientists better understand Mars' early evolution, as well as Earth's. The meteorite, dubbed ALH84001, was found during a snowmobile ride on Dec. 27, 1984 in the Far Western Icefield of Allan Hills in Antarctica. http://www.marsnews.com/archives/2010/04/17/oldest_mars_meteorite_younger_than_thought.html Meteorites Sat, 17 Apr 2010 19:05:11 -0800 The methane found on Mars is not brought to the planet by meteor strikes, scientists say. Meteoritic material subjected to high temperatures did not release enough methane to account for the amount believed to be released on Mars. The researchers argue that the methane must therefore be created by geologic or chemical processes, or it is a by-product of microbial life. The work appears in Earth and Planetary Science Letters. The origin of the methane on Mars has remained a mystery since it was first detected in 2004. Because methane has a limited lifetime in the Martian atmosphere before degrading, some process must be pumping hundreds of tonnes of it into the Martian atmosphere annually to keep it at the levels that have been detected. http://www.marsnews.com/archives/2009/12/09/mars_methane_not_from_meteors.html Life on Mars Wed, 09 Dec 2009 10:37:50 -0800 A research team at Johnson Space Centre in Houston has been re-examining a meteorite that hit Antarctica 13,000 years ago, and found the most compelling evidence yet that the planet once harboured bacterial life. The team says that microscopic crystals found in the rock are almost certainly fossilised bacteria that have many characteristics in common with bacteria found on Earth. “The evidence supporting the possibility of past life on Mars has been slowly building up during the past decade,” said David McKay, NASA chief scientist for exploration and astrobiology. “This evidence includes signs of past surface water including remains of rivers, lakes and possibly oceans and signs of current water near or at the surface.” http://www.marsnews.com/archives/2009/12/01/nasa_compelling_evidence_of_life_on_mars.html Life on Mars Tue, 01 Dec 2009 15:25:59 -0800 NASA's Mars Exploration Rover Opportunity has found a rock that apparently is another meteorite, less than three weeks after driving away from a larger meteorite that the rover examined for six weeks. Opportunity used its navigation camera during the mission's 2,022nd Martian day, or sol, (Oct. 1, 2009) to take this image of the apparent meteorite dubbed "Shelter Island." The pitted rock is about 47 centimeters (18.5 inches) long. Opportunity had driven 28.5 meters (94 feet) that sol to approach the rock after it had been detected in images taken after a drive two sols earlier. Opportunity has driven about 700 meters (about 2,300 feet) since it finished studying the meteorite called "Block Island" on Sept. 11, 2009. http://www.marsnews.com/archives/2009/10/02/opportunity_finds_another_meteorite.html Mars Exploration Rovers Fri, 02 Oct 2009 21:34:35 -0800 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. http://www.marsnews.com/archives/2009/08/01/opportunity_spies_unusual_rock_large_meteorite.html Meteorites Sat, 01 Aug 2009 19:42:05 -0800 NASA's rover Spirit has turned its gaze away from the Martian rocks at its wheels and looks skyward in an attempt to spot a meteor shower. Mars is currently passing through debris left by Halley�s comet and the Spirit team hope the rover might spot bright streaks left in the sky as the Red Planet spins through the ghost of the comet's tail. The rover's panoramic camera has so far spotted several streaks in the Martian night sky. However, these may turn out to be the result of cosmic rays � highly energetic particles that zoom from all directions in space � rather than a meteor shower produced by the long-gone comet. http://www.marsnews.com/archives/2005/11/23/rover_hunts_halleys_comet_in_martian_sky.html Meteorites Wed, 23 Nov 2005 11:36:45 -0800 A study of meteorites chipped off the surface of Mars suggests the planet has been frozen for 4 billion years and probably never had the warm wet conditions that could have given rise to life, two researchers said Thursday. Their study of two meteorites that fell to Earth suggests they were never in warm conditions. The report, published in the journal Science, contradicts theories the now-frozen planet may once have been warm enough for life to have arisen. http://www.marsnews.com/archives/2005/07/22/meteor_study_pours_cold_water_on_warm_mars_theory.html Meteorites Fri, 22 Jul 2005 00:01:41 -0800 NASA's Spirit rover photographed a streak of light that was likely part of a martian meteor shower, scientists announced today. The picture is the first of a shooting star above Mars. Further, the flash has been traced back to its parent comet. And now astronomers figure they should be able to forecast martian meteor showers. http://www.marsnews.com/archives/2005/06/01/first_shooting_star_seen_from_mars.html Meteorites Wed, 01 Jun 2005 12:18:05 -0800 NASA�s Opportunity Mars rover has completed its inspection of �Heat Shield Rock� -- an iron meteorite the robot came across at Meridiani Planum, a cratered flatland that the machine has called home since landing on the red planet over a year ago. The pitted, basketball-size meteorite is mostly made of iron and nickel, as detected by the rover�s set of onboard spectrometers -- devices that map the presence of different elements on the surface of Mars. Meteors, often called �shooting stars� have been seen blazing through the Martian sky by both Opportunity and its sister ship, Spirit, now rolling through the Columbia Hills at Gusev Crater. http://www.marsnews.com/archives/2005/01/26/shooting_stars_on_mars_messages_from_a_meteorite.html Meteorites Wed, 26 Jan 2005 12:01:23 -0800 The discovery of an iron meteorite sitting on Mars by NASA�s Opportunity rover has kick-started a wide-ranging discussion as to what the find may be telling us about the planet itself, past water conditions there, and just how peppered the red planet might be with the fallen objects. Roughly the size of a basketball, the object is mostly made of iron and nickel, and is the first meteorite of any type ever identified on another planet. http://www.marsnews.com/archives/2005/01/20/mars_rovers_meteorite_discovery_triggers_questions.html Meteorites Thu, 20 Jan 2005 10:31:01 -0800 In a stroke of luck, the NASA rover Opportunity has discovered a basketball-size metal meteorite sitting on the surface of Mars, the mission's main scientist said Tuesday. Scientists believe the meteorite might lead to clues about how martian winds are reshaping the planet's surface. Opportunity came upon the meteorite last week while performing other tasks. Tests confirmed it was a nickel-iron meteorite, said Steve Squyres, a Cornell University scientist who is the principal investigator for NASA's Mars Exploration Rovers mission. http://www.marsnews.com/archives/2005/01/19/nasa_rover_finds_meteorite_on_mars_surface.html Meteorites Wed, 19 Jan 2005 00:07:13 -0800 Scientists in the department of Geology and Geophysics at Yale University have devised a method to precisely date the timing and temperature of a meteorite impact on Mars that led to ejection of a piece of the planet into space and its eventual impact on Earth. Meteorites are the main source of mass exchange between planets and carry with them characteristic clues about the nature and history of the planets or planetesimals where they originated, the impacts that dislodged them, and the time they spent in space. Kyoungwon Kyle Min, postdoctoral fellow in geology, reported an innovation for determining the timing and temperatures of ancient impacts that liberate meteorites from extraterrestrial bodies such as Mars. http://www.marsnews.com/archives/2004/10/25/martian_meteorite_measurements_give_information_on_planet_evolution.html Meteorites Mon, 25 Oct 2004 15:07:40 -0800