http://www.marsnews.com/ en-us tourdemars@marsnews.com Copyright 2012 Mon, 06 Feb 2012 14:08:32 -0800 Wed, 15 Feb 2012 14:38:34 -0800 http://www.movabletype.org/?v=3.2 tourdemars@marsnews.com 60 ESA's Mars Express has returned strong evidence for an ocean once covering part of Mars. Using radar, it has detected sediments reminiscent of an ocean floor within the boundaries of previously identified, ancient shorelines on Mars. The MARSIS radar was deployed in 2005 and has been collecting data ever since. Jérémie Mouginot, Institut de Planétologie et d'Astrophysique de Grenoble (IPAG) and the University of California, Irvine, and colleagues have analysed more than two years of data and found that the northern plains are covered in low-density material. "We interpret these as sedimentary deposits, maybe ice-rich," says Dr Mouginot. "It is a strong new indication that there was once an ocean here." http://www.marsnews.com/archives/2012/02/06/esas_mars_express_radar_gives_strong_evidence_for_former_mars_ocean.html Planetology Mon, 06 Feb 2012 14:08:32 -0800 Anomalies in the operation of the solid-state mass memory system on board Mars Express have caused science observations to be temporarily halted. A technical work-around is being investigated that will enable the resumption of a number of observations and should evolve into a long-term solution. In mid-August, Mars Express autonomously entered safe mode, an operational mode designed to safeguard both the spacecraft itself and its instrument payload in the event of faults or errors. The cause of entering the safe mode was a complex combination of events relating to reading from and writing to memory modules in the Solid-State Mass Memory (SSMM) system. This is used to store data acquired by the instruments and housekeeping data from the spacecraft's subsystems, prior to its transmission to Earth, and is also used to store commands for the spacecraft that have been received from the ground stations, while awaiting execution. http://www.marsnews.com/archives/2011/11/01/mars_express_observations_temporarily_suspended.html Mars Express Tue, 01 Nov 2011 21:47:17 -0800 ESA’s Mars Express has spotted a rare case of a crater once filled by a lake, revealed by the presence of a delta. The delta is an ancient fan-shaped deposit of dark sediments, laid down in water. It is a reminder of Mars’ past, wetter climate. The delta is in the Eberswalde crater, in the southern highlands of Mars. The 65 km-diameter crater is visible as a semi-circle on the right of the image and was formed more than 3.7 billion years ago when an asteroid hit the planet. http://www.marsnews.com/archives/2011/09/03/rare_martian_lake_delta_spotted_by_mars_express.html Mars Express Sat, 03 Sep 2011 16:10:00 -0800 ESA’s Mars Express has returned new views of pedestal craters in the Red Planet’s eastern Arabia Terra. Craters are perhaps the quintessential planetary geological feature. So much so that early planetary geologists expended a lot of effort to understand them. You could say they put craters on a pedestal. This latest image of Mars shows how the Red Planet does it in reality. Craters are the result of impacts by asteroids, comets and meteorites. In a pedestal crater, the surrounding terrain is covered by pulverised rock thrown out of the crater. This material creates a platform or pedestal around the crater often with steep cliffs, and is usually rich in volatile materials such as water and ice. http://www.marsnews.com/archives/2011/02/06/mars_express_puts_craters_on_a_pedestal.html Mars Express Sun, 06 Feb 2011 20:23:00 -0800 Without doubt, Phobos is the grooviest moon of the Solar System. By that I mean, that it is covered with a multitude of parallel grooves. Initially, it was thought that these markings radiated away from the largest crater on Phobos. Called Stickney, the crater has a diameter of 9 km and is the most obvious feature of the moon’s pockmarked surface. Some thought that the grooves were debris ejected across Phobos during Stickney’s creation. In other words, they were similar to the bright rays of material seen emanating from some craters on the Moon. Most thought that they were fractures in the moon, opened up by the mighty impact. But these hypotheses were based upon an incomplete picture of Phobos – literally and metaphorically. http://www.marsnews.com/archives/2010/03/21/the_groovy_moon.html Mars Express Sun, 21 Mar 2010 14:39:38 -0800 Unfortunately for anyone looking to terraform Mars, a new study shows that powerful waves of solar wind periodically strip the Red Planet of its atmosphere. Scientists had known for years that Mars has atmosphere troubles, but only by analyzing new data from he Mars Express spacecraft were they able to identify the special double solar waves as the specific cause. Double solar waves are a rare phenomenon that result when the Sun emits waves of differing speeds. If a fast wave follows a slow wave, the fast wave crashes into the back of the slow one, rolling them both up into a super-charged double wave. Scientists were able to correlate Martian atmosphere loss, as measured by the the Mars Express spacecraft, with records of double radiation waves in 2007 and 2008 taken by the Advanced Composition Explorer spacecraft. According to the study, one third of Martian atmosphere loss occurs during these waves, which are only present 15 percent of the time. http://www.marsnews.com/archives/2010/03/17/bad_news_for_terraformers_periodic_bursts_of_solar_radiation_destroy_the_martian_atmosphere.html Terraforming Wed, 17 Mar 2010 13:30:54 -0800 Fresh imagery from Europe's Mars Express orbiter shows the Martian moon Phobos in sharp, 3-D detail. This isn't the first time Phobos has gotten its close-up, but interest in the irregular moon is rising - in part because it's increasingly seen as a steppingstone for Mars-bound astronauts. Last month, NASA shifted its focus from sending humans back to the moon to a "flexible path" that includes the moons of Mars as potential destinations. The idea is that low-gravity locales such as Phobos (and Mars' other moon, Deimos) should be easier to get to because they're more accommodating for landing and ascent. http://www.marsnews.com/archives/2010/03/17/martian_moon_in_spotlight.html Mars Express Wed, 17 Mar 2010 13:26:50 -0800 Images from the recent flyby of Phobos, on 7 March 2010, are released today. The images show Mars’ rocky moon in exquisite detail, with a resolution of just 4.4 metres per pixel. They show the proposed landing sites for the forthcoming Phobos-Grunt mission. ESA's Mars Express spacecraft orbits the Red Planet in a highly elliptical, polar orbit that brings it close to Phobos every five months. It is the only spacecraft currently in orbit around Mars whose orbit reaches far enough from the planet to provide a close-up view of Phobos. http://www.marsnews.com/archives/2010/03/15/phobos_flyby_images.html Mars Express Mon, 15 Mar 2010 11:18:28 -0800 The European Mars Express (Mex) probe has made its closest flyby of the Martian moon Phobos, passing just 67km (42 miles) from its surface. No manmade object has ever been so near to the natural satellite. The approach is one of a series being made by Mex as it seeks to understand the origin of the moon. Previous flybys have indicated that Phobos has an extremely low density, suggesting that its surface probably hides many large interior voids. Scientists suspect the moon is simply a collection of planetary rubble that coalesced around the Red Planet sometime after its formation. http://www.marsnews.com/archives/2010/03/04/closest_phobos_flyby_gathers_data.html Mars Express Thu, 04 Mar 2010 11:03:10 -0800 A European space probe is on track for a close encounter with the Martian moon Phobos, an odd, potato-shaped satellite -- origins unknown -- that may be partly hollow. Mapping Phobos' gravity is among scientists' top priorities when the Mars Express spacecraft soars as close as 50 kilometers (31 miles) above the moon Wednesday night. Previous passes of Phobos by Mars Express have raised as many questions as they've answered. For example, calculations of the moon's density led scientists to the surprising theory that parts of Phobos may be hollow. Minute changes in the probe's flight path -- tracked by a radio signal -- as it passes over the moon Wednesday will be closely monitored in an attempt to correlate Phobos' gravitational tugs with internal structural variations. http://www.marsnews.com/archives/2010/03/02/mars_express_swings_by_phobos.html Mars Express Tue, 02 Mar 2010 11:10:38 -0800 On 3 March 2010 Mars Express will make its closest ever approach to Phobos, the larger of the two Martian moons. During a series of flybys, spanning six weeks, all seven instruments onboard Mars Express will be utilised to study Phobos. The close approach provides a first opportunity to perform a unique gravity experiment that may reveal the distribution of mass within this intriguing moon. http://www.marsnews.com/archives/2010/02/27/mars_express_to_make_closest_ever_approach_to_phobos.html Mars Express Sat, 27 Feb 2010 00:13:07 -0800 For the first-time ever, VMC has imaged what we believe to be the shadow of Mars' moon Phobos crossing the surface of Mars. The shadow cast by Phobos as it passes between the Sun and Mars was photographed by VMC on 30 January, just as Mars Express approaches an intensive scientific observation campaign of Phobos. http://www.marsnews.com/archives/2010/02/02/vmc_first_the_shadow_of_phobos.html Mars Express Tue, 02 Feb 2010 09:02:35 -0800 On 26 January, Mars Express completed its 7777th orbit around the Red Planet, an auspicious milestone as the satellite is readied for the closest-ever flyby of Phobos, scheduled for just a few weeks from now. Mars Express has been in orbit since 25 December 2003, returning a wealth of scientific information and some of the most stunning high-resolution imagery of the Red Planet ever. Its data have allowed scientists to measure the abundance of water ice and vapour in the martian subsurface, surface and the atmosphere, as well as previously unknown methane in the atmosphere. Mars Express' highly elliptical orbit will enable Mars Express, on 3 March, to conduct the closest flyby and examination of Phobos, Mars’ largest moon. The flyby, at a planned altitude of just 50 km, will collect very precise radio Doppler data to help determine the moon’s gravity field more accurately than ever. http://www.marsnews.com/archives/2010/01/29/auspicious_orbit_marks_runup_to_phobos_flyby.html Mars Express Fri, 29 Jan 2010 10:21:38 -0800 FIRST there were canals. Then an ominous face lept from Mars' mysterious surface. Now, what looks like rows of alien trees is causing something of a stir. Like the tall tales that have gone before it, this latest image of Mars is nothing but an optical illusion. Taken by NASA and the European Space Agency's Mars Express Orbiter, the picture is from a collection showing vast sand dunes and icy landscapes on the surface of the red planet. Australian National University associate professor of astronomy Charley Lineweaver said the sand dunes were extremely steep, and the "tree-like" shapes were simply gullies running down the slopes. http://www.marsnews.com/archives/2010/01/21/photographic_illusion_shows_trees_on_mars.html Mars Express Thu, 21 Jan 2010 23:42:30 -0800 For the very first time, the martian moons Phobos and Deimos have been caught on camera together. ESA’s Mars Express orbiter took these pioneering images last month. Apart from their ‘wow’ factor, these unique images will help the HRSC team validate and refine existing orbit models of the two moons. Phobos, the larger of the two moons, orbits closer to the Red Planet, circling it every 7 hours and 39 minutes. It travels faster relative to Mars than the Moon relative to Earth. It was 11 800 km from Mars Express when the images were taken. Deimos was 26 200 km away. http://www.marsnews.com/archives/2009/12/11/martian_moons_phobos_and_deimos_together_in_one_image_for_the_first_time.html Mars Express Fri, 11 Dec 2009 16:00:03 -0800