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Breaking the ice

Breaking the ice Sister Moon you be my guide
in your blue blue shadow I will hide.
All the people sleep tonight
I'm all by myself in your silver light.
I would gaze at your face the whole night through
I go out of my mind before you. (Sting)

AFTER two years of gazing and careful analysis it is time for lunar scientists to say 'Eureka! ': they have detected water on the Moon. The finding boosts humanity's cherished dream of living on the Moon. A huge icy crater would not only provide a source of water but that water could in turn be converted through electrolysis into its component parts - hydrogen and oxygen cutting costs of lugging these essentials on lunar trips. Hydrogen and oxygen are essential elements of rocket fuel which means the Moon could also provide an effective launching pad for new space exploration efforts. "If you could wish for any one thing there to make it easier to explore with it would be water said Anthony Cook, astronomical observer at the Griffith Observatory in Los Angeles, us. And apparently there is water now, lying in a huge crater created a few billion years ago by a crashing asteroid or comet in the Aitkin basin in the south pole of the Moon (the dark spot in the picture above).
Dark side of the moon The ice was found in a huge crater deep in the south pole of the Moon said Rick Lehner, spokesperson for the Pentagon's Ballistic Missile Defense Organization (BMDO), which was colloborating with National Aeronautical and Space Administration (NASA) on the Clementine Mission, which was part of the former Star Wars project. It is an extremely significant discovery pointed out Cook. He added that water would make exploration easier: With water there you could have enclosed areas to grow plants grow your own food make your own fuel and make your own air. You don't have to launch all that stuff from big rockets on the earth."

The size of the crater according to Lehner, is twice the size of Puerto Rico and 13 km deep or higher than Mt Everest the tallest peak on earth. He said the ice formation is the size of a small lake and is between 10 and 100 ft deep. According to the most popular belief held by scientists about 3.6 billion years ago a comet crashed into the moon and water droplets on its tail were left in the bottom of the crater the deepest crater in the solar system.

Because the south side of the moon is always dark the temperature in this crater is about minus 230'cnearlyas cold as any environment can get. Scientists say that it is because of this cold trap that water could not escape from the crater. Another interesting facet arises from the fact that there is no atmosphere in the moon to hold gases or moisture. Therefore the signs of ice could offer intriguing new clues about the moon's origin more than four billion years ago.

The ice deposit is not at all like a frozen lake where scientists might try playing ice-hockey in one-sixth gravity. Instead the survey seemed to reveal a vast landscape of some 4800sq km in which ice crystals are mixed with dirt, a kind of permafrost that is presumably the residue of moisture from comets striking the Moon over the last three billion years. "We think we have found ice said Paul D Spudis, a geologist at the Lunar and Planetary Institute in Houston. We are not positive. But we see signals consistent with ice and we think it's there."

In fact Clementine did not have a regular 'radar' that could scan anything on the lunar surface. Instead Stuart Nozett of the US Air Force's Phillips Laboratory in Virginia decided to use the radio transmitters for that. Radio waves from the transmitters hit the lunar surface and bounced back and were tracked in an earth station. Since rocks are opaque to radio waves those that hit the former came back clear. But those waves which hit the ice jostled around inside it for a while before getting back to earth. This left the return images with a tell-ice smudge. The original mission
Mission Clementinea us $75 million plan to test 'Star Wars' sensors developed to detect and track missiles was launched in January 1994.The Deep Space Program Science Experiment was the first of a series of Clementine technology demonstrations jointly sponsored by the BMDO and the NASA. Its principal objective is to qualify lightweight imaging sensors and component technologies for the next generation of department of defense spacecraft.

However the Clementine returns data of interest to the civilian science sector. It represents a new class of small low-cost and highly capable spacecraft that fully embrace emerging lightweight technologies to enable a series of long-duration deep space missions.

The story took a new turn at this point. As an unexpected by-product the Clementine discovered ice on the Moon though scientists admit there could be small amounts of other substances like methane or carbon dioxide mixed in it.

But the discovery also poses new technological challenges because it is not easy to use the south side of the Moon as a centre for setting up are search base. Spudis, however noted that there was a high point in the basin, near the actual pole that is almost permanently in sunlight. This would be an excellent site he said for a lunar installation with solar power panels to run equipment to melt the ice for water or convert it to breathing oxygen or rocket fuel. However he conceded We have a long way to go before we have people living on the Moon. What this is, is an indication that living on the Moon might be possible.

The Clementine mission demonstrates and validates BMDO'S lightweight technologies with a space flight mission. Another key objective is to use BMDO technologies for scientific purposes. The mission also demonstrates the benefits of a streamlined management approach to meet costs and schedule constraints. Even after the mission detected the ice scientists debated for months whether it was water or some other frozen liquid or gases. But Lehner said the' consensus' of the scientific panel is that the pond is frozen water.

Clementine was the first American craft to explore the Moor) since the final Apollo landing in December 1972 and the last visit by any craft since the unmanned Russian Luna 24 landed there in 1976 picked up rock samples and returned them to Earth.

The next mission to the Moon is Lunar Prospector a small unmanned craft being developed for NASA by the Ames Research Center in Mountain View California and built by Lockheed-Martin Corporation in Denver. Scheduled for launching next September the spacecraft is to go in to an orbit of the Moon that repeatedly crosses both poles. Its five remote-sensing instruments are designed to map the composition of the lunar surface and observe its magnetic and gravitational fields. The NASA scientists said that Lunar Prospector's two neutron spectrometers should be able to measure the amount of hydrogen on the lunar surface to an accuracy of 50parts per million. "This will permit scientists to infer the presence or absence of ice with greater precision than possible via the innovative but indirect method used by the Clementine team they said.

Written by Deepan Joshi

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