Beagle 2
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Beagle 2 was an unsuccessful landing spacecraft that formed part of the European Space Agency's 2003 Mars Express mission.
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Background
Beagle 2 was conceived, designed and built by a group of British academics headed by Professor Colin Pillinger of the Open University, in collaboration with the University of Leicester. Its purpose was to search for signs of Martian life, past or present, and its name reflected this goal, as Professor Pillinger explained:
- "HMS Beagle was the ship that took Darwin on his voyage around the world in the 1830s and led to our knowledge about life on Earth making a real quantum leap. We hope Beagle 2 will do the same thing for life on Mars."
Mars Express launched from Baikonur at 17:45 UTC (18:45 BST) on 2 June 2003. The Beagle 2 was a Mars lander initially mounted on the top deck of the Mars Express Orbiter. It was released from the Orbiter on December 19, 2003 and was expected to land on Mars on December 25 at 02:54 UTC. A point at 10.6°N, 270°W in Isidis Planitia, a large flat sedimentary basin that overlies the boundary between the ancient highlands and the northern plains of Mars, was chosen as the landing site.
The lander was expected to operate for about 180 days and an extended mission of up to one Martian year (687 Earth days) was thought possible. The Beagle 2 lander objectives were to characterize the landing site geology, mineralogy, geochemistry and oxidation state, the physical properties of the atmosphere and surface layers, collect data on Martian meteorology and climatology, and search for possible signatures of life.
In an effort to publicise the project and gain financial support, its designers sought and received the endorsement and participation of British artists. The mission's call-sign was composed by the band Blur, and the test card intended for calibrating Beagle 2's cameras after landing was painted by Damien Hirst.
The Lander Operations Control Centre (LOCC) at the National Space Centre in Leicester, from which the spacecraft was being controlled, was open to the public.
Spacecraft and subsystems
Beagle 2 had a robotic arm known as the Payload Adjustable Workbench (PAW), designed to be extended after landing. The PAW contained a pair of stereo cameras, a microscope (with a 6 micrometre resolution), a Mössbauer spectrometer, an X-ray spectrometer, a drill for collecting rock samples and a spotlamp. Rock samples were to be passed by the PAW into a mass spectrometer and gas chromatograph in the body of the lander, to measure the relative proportions of different isotopes of carbon. Since carbon is thought to be the basis of all life, these readings could have revealed whether the samples contained the remnants of living organisms.
In addition, Beagle 2 was equipped with a small "mole" (Planetary Undersurface Tool, or PLUTO), to be deployed by the arm. PLUTO had a compressed spring mechanism designed to enable it to move across the surface at a rate of about 1 cm every 5 seconds and to burrow into the ground and collect a subsurface sample in a cavity in its tip. The mole was attached to the lander by a power cable which could be used as a winch to bring the sample back to the lander.
The robot arm was equipped with a grinder and corer, a device to collect a core sample from inside any rocks within reach of the robot arm. The lander had the shape of a shallow bowl with a diameter of 0.65 m and a depth of 0.25 m. The cover of the lander was hinged and folded open to reveal the interior of the craft which holds a UHF antenna, the 0.75 m long robot arm, and the scientific equipment. The main body also contained the battery, telecommunications, electronics, and central processor, and the heaters. The lid itself further unfolded to expose four disk-shaped solar arrays. The lander package had a mass of 69 kg at launch but the actual lander would have been only 33.2 kg at touchdown.
Mission profile
Beagle 2 was launched with the Mars Express orbiter and was released on a ballistic trajectory towards Mars on 19 December 2003 at 8:31 UT. Beagle 2 coasted for five days after release and entered the Martian atmosphere at over 20,000 km/h on the morning of 25 December. After initial deceleration in the Martian atmosphere from simple friction, parachutes were to be deployed and about 1 km above the surface large airbags were to inflate around the lander and protect it when it hit the surface. Landing was expected to occur at about 02:45 UT on 25 December (9:45 p.m. EST 24 December). After landing the bags were supposed to deflate and the top of the lander was to open. The top should have unfolded to expose the four solar array disks. Within the body of the lander a UHF antenna was to be deployed. A signal was supposed to be sent to Mars Express after landing and another the next (local) morning to confirm that Beagle 2 survived the landing and the first night on Mars. A panoramic image of the landing area was then supposed to be taken using the stereo camera and a pop-up mirror, after which the lander arm would have been released. The lander arm was to dig up samples to be deposited in the various instruments for study, and the "mole" would have been deployed, crawling across the surface to a distance of about 3 metres from the lander and burrowing under rocks to collect soil samples for analysis.
The government spent more than £22 million ($40 million U.S.) on Beagle 2, with the private sector providing more than £44 million ($80 million U.S.). [1] (http://www.space.com/news/beagle_update_040524.html)
Mission progress
Although the Beagle 2 craft successfully deployed from the Mars Express "mother ship", confirmation of a successful landing was not forthcoming. Confirmation should have come on 25 December 2003, when the Beagle 2 should have contacted NASA's Mars Odyssey spacecraft that was already in orbit. In the following days, the Lovell Telescope at Jodrell Bank also failed to pick up a signal from Beagle 2. The team said they were "still hopeful" of finding a successful return signal.
Attempts were made throughout January and February of 2004 to contact Beagle 2 using Mars Express. The first of these occurred on January 7, 2004, but ended in failure. Although regular calls were made, particular hope was placed on communication occurring on the January 12, when Beagle 2 was pre-programmed to expect the Mars Express probe to fly overhead, and on the February 2, when the probe was supposed to resort to the last communication back-up mode: Autotransmit. However, no communication was established with Beagle 2.
On December 31, 2003, it was reported that a crater was photographed in the center of the target landing site. It is possible that this could be the final resting place of Beagle 2, the craft unable to transmit from the shadow of the crater walls.
Beagle 2 was declared lost on February 6, 2004, by the Beagle 2 Management Board. On February 11, ESA announced an inquiry would be held into the failure of Beagle 2.
ESA Inquiry report
In May, 2004, the report form the Commission of Inquiry on Beagle 2 was submitted to ESA and the UK's science minister Lord Sainsbury. It is not planned to be published in detail, but a list of 19 recommendations were announced to the public.
Professor David Southwood, ESA's director of science, listed the following scenarios how the landing might have failed:
- Beagle entered an atmosphere that was not predicted by scientists and could have burnt up. It may even have "bounced off into space";
- the probe's parachute or cushioning airbags failed to deploy or deployed at the wrong time;
- Beagle's backshell tangled with the parachute preventing it from opening properly;
- Beagle became wrapped up in its airbags or parachute on the surface and could not open.
Legacy
In 2004, Pillinger announced plans to launch an improved successor, provisionally entitled Beagle 2: Evolution, in 2009.
Related articles
External links
- Beagle 2's Official Site (http://www.beagle2.com)
- Mars Express (http://spdext.estec.esa.nl/content/doc/8f/27791_.htm)
- BBC guide to Beagle 2 (http://news.bbc.co.uk/1/shared/spl/hi/sci_nat/03/race_to_mars/mission_guide/html/beagle_2.stm)
- NSSDC page on Beagle 2 (http://nssdc.gsfc.nasa.gov/database/MasterCatalog?sc=2003-022C)
- Beagle 2 may have sped to its death (http://www.newscientist.com/news/news.jsp?id=ns99994752) (New Scientist, 8 March 2004 )
- ESA/UK Commission of Inquiry report. (PDF file) (http://www.bnsc.gov.uk/assets/channels/resources/press/report.pdf)de:Beagle 2