Where on Mars is Beagle?
No contact has been made with the Beagle 2 lander, despite repeated efforts over the last few days to communicate via the Mars Express and Mars Odyssey spacecraft and the Jodrell Bank radio telescope in Cheshire, UK.
|Mars Beagle 2 spacecraft.
Colin Pillinger: I think there were a lot of failures of missions designed to go to Mars. And we don't necessarily know what experiments were on some of those Russian missions. But all of them had to get down before they could do any experiments.
I think the real thing that is driving us back to wanting to look at whether there is life on Mars is something that Viking did that nobody anticipated, nobody planned. It was that they were able to show that we have martian meteorites on Earth and the martian meteorites clearly led us to believe that the conditions on Mars are more appropriate for life than we had believed from Viking. It wasn't that Viking didn't find life, it was that they thought the conditions were just so horrid, so harsh, nobody anticipated that life could exist there.
The discovery of water in martian meteorites was made just after Viking. Of course, we didn't know then they were martian meteorites. But we found evidence of water trickling through martian meteorites, we found carbonates in martian meteorites that was definitely indigenous. And we found organic matter.
I believe that the organic matter is there in an amount that can't just be explained by contamination. However, I can't prove it. And if I can't prove something, I just simply say, right, what are we going to do next? Go find another experiment.
Photo Credit: ESA
At a press briefing in London, members of the Beagle 2 team described the latest efforts to contact their missing lander.
"We haven't found Beagle 2, despite three days of intensive searching," said Professor Colin Pillinger, lead scientist for Beagle 2. "Under those circumstances, we have to begin to accept that, if Beagle 2 is on the Martian surface, it is not active.
|Locating Landers on Mars from Orbit. The arrows point to the dust-covered remnants of Viking 1 (VL1) and the Mars Pathfinder (MPF) lander sites. MGS MOC Release No. MOC2-595, 4 January 2004
Image Credit: Mars Global Surveyor, Malin Space Systems
"That isn't to say that we are going to give up on Beagle. There is one more thing that we can do - however, it is very much a last resort. We will be asking the American Odyssey spacecraft (team) tomorrow whether they will send an embedded command - a hail to Beagle with a command inside it.
If it gets through, it will tell Beagle to switch off and reload the software. We are now working on the basis that there is a corrupt system and the only way we might resurrect is to send that command."
"We can also ask Mars Express to send that command. However, they cannot send it probably until the 2 or 3 February," he added.
"We'll move with the next phase in the search for Beagle 2," said Professor Pillinger. "We have discussed on our side of the house what we intend to do in the future. We are dedicated to trying to refly Beagle 2 in some shape or form, therefore we need to know how far it got because we need know which parts of this mission we don't have to study in further detail."
Detailing the efforts to contact Beagle 2 in recent days, Mark Sims, Beagle 2 Mission Manager from the University of Leicester, explained that the lander should have entered an emergency communication mode known as CSM2 no later than 22 January. In this mode, the spacecraft's receiver is switched on throughout daylight hours on Mars. The only possible explanation that no communication has been established during the last few days is that the lander's battery is in a low state of charge.
Meanwhile, the academia-industry "Tiger Team" at the National Space Center in Leicester is beginning to concentrate on detailed analysis of the possible causes for failure of the mission and the lessons that can be learned for future missions.
To Astrobiology Magazine, Pillinger described Beagle's location in an equatorial region called Isidis Planitia: "Everything we could possibly think of went into choosing Isidis. We wanted somewhere we could keep the scientists happy and somewhere the engineers wouldn't throw a wobbly. The engineers want low altitude, which makes the parachute work better; they don't want the place strewn with rocks, it could burst the gas bags; they don't want slopes because they give you lateral velocity that you don't like; nobody wanted to go to high latitudes, because it gets cold up there; we chose the northern hemisphere because it was going toward spring and summer, and of course the altitude there as well."
"We liked a place where there was a potential of different kinds of rocks," said Pillinger. "So Isidis is nice because it's an in-fill basin, which might have lots of materials from the southern highlands washed down into it. We chose a place south of two recognizable sizable craters because we felt there was a possibility that some materials had been ejected from the floor of the craters".
The analysis of the mission now under way includes an assessment of the landing site ellipse from orbital images, reanalysis of atmospheric conditions during the entry into the Martian atmosphere on 25 December, examination of the separation from Mars Express and of the cruise phase preceding arrival at Mars.
One extremely useful piece of evidence could be provided by an image of the lander. The team is hoping that the High Resolution Stereo Camera on Mars Express or the camera on board Mars Global Surveyor (MGS) may eventually be able to capture an image that reveals its location on the Martian surface.
|Click for larger view. Annotated image from Mars Orbital Camera showing Spirit's backshell, parachute, and rover base petal. Credit: MSSS/NASA/JPL
The locations for Viking, Pathfinder, and Spirit were only recently determined by using sight lines from the landers to near and far objects seen in the pictures acquired by the landers, and then matching these to locations in earlier, 1.5 to 3.0 meter/pixel Mars Orbital Camera images. Then, the images, shown here, were acquired by MGS so that the actual landers, sitting on the martian surface, might be resolved.
This technique only works well when the location of the lander is already fairly-well established.
It would be extremely difficult to find a lander for which the location is uncertain, such as Viking 2 or Mars Polar Lander (in fact, for Mars Polar Lander, it would take over 60 years to map out the entire landing ellipse in which the spacecraft was lost).
The successful orbital insertion of the orbiter, Mars Express, also promises high resolution overhead images. [Having entered polar orbit on Sunday, the orbiter first passed over the Beagle 2 target site on January 7]. Over its multi-year mission life, an onboard camera on Mars Express offers high-resolution stereo views of Mars. Its comprehensive maps will feature 10 meter resolution, but some particularly interesting regions will get a close-up view to 2 meters [about the size of small car, as seen from orbit].
The Beagle lander was small - a mere 30 kg (66 pounds) - and was never intended to move from its landing spot. But at its core sat a miniaturized version of a sophisticated chemical laboratory. The lander's Gas Analysis Package, or GAP, was central to its mission to discover signs of past or present life on Mars. The only previous life-detection experiments on Mars were carried out by NASA's Viking 1 and 2 landers in 1976. Viking's biology experiments did not produce unequivocal evidence for present or past life on Mars. But the results didn't rule out life either. Nearly thirty years later, astrobiologists continue to disagree about how to interpret Viking's results.
Related Web Pages
Five Year Retrospective: Mars Pathfinder
Open University: Beagle
Space Research Centre: Leicester
Mars Express PPARC
ESA's Beagle: Sniffing Out Life on Mars
Call from the Red Phone
Isidis, Martian Impact Basin