 |
|
Mars Express radar ready to work
June 23, 2005ESA PR 34-2005. MARSIS, the Mars Advanced Radar for Subsurface and Ionosphere Sounding on board ESA's Mars Express orbiter, is now fully deployed, has undergone its first check-out and is ready to start operations around the Red Planet.
With this radar, the Mars Express orbiter at last has its full complement of instruments available to probe the planet's atmosphere, surface and subsurface structure.
MARSIS consists of three antennas: two 'dipole' booms 20 metres long, and one 7-metre 'monopole' boom oriented perpendicular to the first two. Its importance is that it is the first- ever means of looking at what may lie below the surface of Mars.
The delicate three-stage phase of radar boom deployment, and all the following tests to verify spacecraft integrity, took place between 2 May and 19 June. Deployment of the first boom was completed on 10 May. That boom, initially stuck in unlocked mode, was later released by exploiting solar heating of its hinges.
Taking advantage of the lessons learnt from that first boom-deployment, the second 20-metre boom was successfully deployed on 14 June. Subsequently, ESA's ground team at the European Space Operations Centre (ESOC) in Darmstadt, Germany, commanded the non-critical deployment of the third boom on 17 June, which proceeded smoothly as planned.
MARSIS's ability to transmit radio waves in space was tried out for the first time on 19 June, when the instrument was switched on and performed a successful transmission test.
The instrument works by sending a coded stream of radio waves towards Mars at night, and analysing their distinctive echoes. From this, scientists can then make deductions about the surface and subsurface structure. The key search is for water. But MARSIS's capabilities do not stop there. The same methods can also be used by day to probe the structure of the upper atmosphere.
Before starting its scientific observations, MARSIS has to undergo its commissioning phase. This is a routine procedure for any spacecraft instrument, necessary to test its performance in orbit using real targets in situ. In this case, the commissioning will last about ten days, or 38 spacecraft orbital passes, starting on 23 June and ending on 4 July.
During the commissioning phase, MARSIS will be pointed straight down (nadir pointing mode) to look at Mars from those parts of the elliptical orbit where the spacecraft is closest to the surface (around the pericentre). During this phase, it will cover the areas of Mars between 15° S and 70° N latitude. This includes interesting features such as the northern plains and the Tharsis region, so there is a small chance of exciting discoveries being made early on.
On 4 July, when the commissioning operations end, MARSIS will start its nominal science observations. In the initial phase, it will operate in survey mode. It will make observations of the Martian globe's night-side. This is favourable to deep subsurface sounding, because during the night the ionosphere of Mars does not interfere with the lower-frequency signals needed by the instrument to penetrate the planet's surface, down to a depth of 5 kilometres.
Through to mid-July, the radar will look at all Martian longitudes between 30° S and 60° N latitude, in nadir pointing mode. This area, which includes the smooth northern plains, may have once contained large amounts of water.
The MARSIS operation altitudes are up to 800 kilometres for subsurface sounding and up to 1200 kilometres for studying the ionosphere. From mid-July, the orbit's closest approach point will enter the day-side of Mars and stay there until December. In this phase, using higher frequency radio waves, the instrument will continue shallow probing of the subsurface and start atmospheric sounding.
"Overcoming all the technical challenges to operate an instrument like MARSIS, which had never flown in space before this mission, has been made possible thanks to magnificent cooperation between experts on both sides of the Atlantic," said Professor David Southwood, ESA's Science Programme Director. "The effort is indeed worthwhile as, with MARSIS now at work, whatever we find, we are moving into new territory; ESA's Mars Express is now well and truly one of the most important scientific missions to Mars to date," he concluded.
European Space Agency
The delicate three-stage phase of radar boom deployment, and all the following tests to verify spacecraft integrity, took place between 2 May and 19 June. Deployment of the first boom was completed on 10 May. That boom, initially stuck in unlocked mode, was later released by exploiting solar heating of its hinges.
Taking advantage of the lessons learnt from that first boom-deployment, the second 20-metre boom was successfully deployed on 14 June. Subsequently, ESA's ground team at the European Space Operations Centre (ESOC) in Darmstadt, Germany, commanded the non-critical deployment of the third boom on 17 June, which proceeded smoothly as planned.
MARSIS's ability to transmit radio waves in space was tried out for the first time on 19 June, when the instrument was switched on and performed a successful transmission test.
The instrument works by sending a coded stream of radio waves towards Mars at night, and analysing their distinctive echoes. From this, scientists can then make deductions about the surface and subsurface structure. The key search is for water. But MARSIS's capabilities do not stop there. The same methods can also be used by day to probe the structure of the upper atmosphere.
Before starting its scientific observations, MARSIS has to undergo its commissioning phase. This is a routine procedure for any spacecraft instrument, necessary to test its performance in orbit using real targets in situ. In this case, the commissioning will last about ten days, or 38 spacecraft orbital passes, starting on 23 June and ending on 4 July.
During the commissioning phase, MARSIS will be pointed straight down (nadir pointing mode) to look at Mars from those parts of the elliptical orbit where the spacecraft is closest to the surface (around the pericentre). During this phase, it will cover the areas of Mars between 15° S and 70° N latitude. This includes interesting features such as the northern plains and the Tharsis region, so there is a small chance of exciting discoveries being made early on.
On 4 July, when the commissioning operations end, MARSIS will start its nominal science observations. In the initial phase, it will operate in survey mode. It will make observations of the Martian globe's night-side. This is favourable to deep subsurface sounding, because during the night the ionosphere of Mars does not interfere with the lower-frequency signals needed by the instrument to penetrate the planet's surface, down to a depth of 5 kilometres.
Through to mid-July, the radar will look at all Martian longitudes between 30° S and 60° N latitude, in nadir pointing mode. This area, which includes the smooth northern plains, may have once contained large amounts of water.
The MARSIS operation altitudes are up to 800 kilometres for subsurface sounding and up to 1200 kilometres for studying the ionosphere. From mid-July, the orbit's closest approach point will enter the day-side of Mars and stay there until December. In this phase, using higher frequency radio waves, the instrument will continue shallow probing of the subsurface and start atmospheric sounding.
"Overcoming all the technical challenges to operate an instrument like MARSIS, which had never flown in space before this mission, has been made possible thanks to magnificent cooperation between experts on both sides of the Atlantic," said Professor David Southwood, ESA's Science Programme Director. "The effort is indeed worthwhile as, with MARSIS now at work, whatever we find, we are moving into new territory; ESA's Mars Express is now well and truly one of the most important scientific missions to Mars to date," he concluded.
European Space Agency
Mars Express Current Events and Mars Express News RSSMars Express observes aurorae on the Red Planet
Scientists using ESA's Mars Express have produced the first crude map of aurorae on Mars. These displays of ultraviolet light appear to be located close to the residual magnetic fields generated by Mars's crustal rocks.
Mars Express mission controllers ready for NASA Phoenix landing
ESA's Mars Express mission control team are ready to monitor Phoenix's critical entry, descent and landing onto the Martian surface on 26 May 2008.
Artificial intelligence boosts science from Mars
Artificial intelligence (AI) being used at the European Space Operations Centre is giving a powerful boost to ESA's Mars Express as it searches for signs of past or present life on the Red Planet.
Plan to identify watery Earth-like planets develops
Astronomers are looking to identify Earth-like watery worlds circling distant stars from a glint of light seen through an optical space telescope and a mathematical method developed by researchers at Penn State and the University of Hawaii.
Mars Express reveals the Red Planet's volcanic past
A new analysis of impact cratering data from Mars reveals that the planet has undergone a series of global volcanic upheavals. These violent episodes spewed lava and water onto the surface, sculpting the landscape that ESA's Mars Express looks down on today.
Mars and Venus are surprisingly similar
Using two ESA spacecraft, planetary scientists are watching the atmospheres of Mars and Venus being stripped away into space. The simultaneous observations by Mars Express and Venus Express give scientists the data they need to investigate the evolution of the two planets' atmospheres.
Ice clouds put Mars in the shade
Until now, Mars has generally been regarded as a desert world, where a visiting astronaut would be surprised to see clouds scudding across the orange sky. However, new results show that the arid planet possesses high-level clouds that are sufficiently dense to cast a shadow on the surface.
Setting stars reveal planetary secrets
Watching the stars set from the surface of the Earth may be a romantic pastime but when a spacecraft does it from orbit, it can reveal hidden details about a planet's atmosphere.
Mars Express probes the Red Planet's most unusual deposits
The radar system on ESA's Mars Express has uncovered new details about some of the most mysterious deposits on Mars: The Medusae Fossae Formation.
The origin of perennial water-ice at the South Pole of Mars
Thanks to data from ESA's Mars Express mission, combined with models of the Martian climate, scientists can now suggest how the orbit of Mars around the Sun affects the deposition of water ice at the Martian South Pole.
More Mars Express Current Events and Mars Express News Articles
 | 21st Century Complete Guide to Mars Exploration: Mars Exploration Rovers 2003-2004 ¿ NASA Spirit and Opportunity Rovers (MER) and the Mars Express Beagle 2 Mission (Three CD-ROM Set) by World Spaceflight News This comprehensive set of three CD-ROMs provides a thorough guide to the mission of the twin NASA Mars Exploration Rovers, Spirit and Opportunity, launched in 2003 for an early 2004 landing on the Red Planet. In addition to MER-A and MER-B, there is coverage of the Mars Express mission, including the Beagle 2 lander. This historic program is documented in NASA reports and mission images - there... |
 | Delicias del Mar (Chef Express) (Chef Express) by Trident Press International |
 | The Mars Plasma Environment Mars sits very exposed to the solar wind and, because it is a small planet, has but a weak hold on its atmosphere. The solar wind therefore plays an important role in the evolution of the martian atmosphere. Over the last four decades a series of European missions, first from the Soviet Union and more recently from the European Space Agency, together with a single investigation from the U.S.,... |
 | A Princess of Mars, first novel of the Barsoom series by Edgar Rice Burroughs Science fiction adventure novel first published in... |
| The Chessmen of Mars, fifth novel of the Barsoom series by Edgar Rice Burroughs Science fiction adventure, first published in... |
| The Gods of Mars, second novel of the Barsoom series by Edgar Rice Burroughs Science fiction adventure, first published in... |
| The Warlord of Mars, third novel of the Barsoom series by Edgar Rice Burroughs Science fiction adventure first published in... |
| Thuvia, Maid of Mars, fourth novel of the Barsoom series by Edgar Rice Burroughs Science fiction adventure, first published in... |
| Classic American Fiction: 5 Mars Novels by Edgar Rice Burroughs (Barsoom Series) in a single file, with active table of contents by Edgar Rice Burroughs This Kindle book includes: A Princess of Mars, 1912; The Gods of Mars, 1914; The Warlord of Mars, 1918; Thuvia, Maid of Mars, 1920; and The Chessmen of Mars, all of which are in the "Barsoom" series. According to Wikipedia: "Edgar Rice Burroughs (September 1, 1875 – March 19, 1950) was an American author, best known for his creation of the jungle hero Tarzan and the heroic John Carter,... | |
| Departures Mar/Apr 2001 by Editorial Staff |
| © 2008 BrightSurf.com |