Asteroid probe to land in Australia
AFTER TRAVELLING ALMOST TWO billion kilometres to reach its destination on asteroid Itokawa, the spacecraft Hayabusa is due to land at the Woomera Prohibited Area in South Australia on Sunday night, carrying what scientists hope to be the first ever sample from an asteroid.
The space probe was launched in May 2003 and landed on the asteroid in November 2005. It is now on its final approach to Earth following a seven-week delay due to a fuel leakage.
A large team of scientists from both the Japanese Aerospace Exploration Agency (JAXA) and US space agency NASA have arrived in South Australia to recover the capsule which they anticipate will provide important scientific clues about chemical composition and surface features of the asteroid in space.
“Major scientific find”
Despite the scientists losing control of Hayabusa at one point, they were able to guide it to make two separate landings on Itokawa, which is 540 m long on it’s longest axis and was discovered in 1998. The probe collected important information about the asteroid’s gravity and surface condition. Although many samples have been collected from the Moon, and various other celestial bodies it will be the first sample ever acquired from the Asteroid Belt, which is found between Jupiter and Mars.
Study of the asteroid’s composition will shed some light on the early history of the Solar System and the formation of planets, and could also help reduce the threat of asteroid collisions in the future, experts say. “We can look at the asteroids and make a colour determination to find out their origin but one of the big issues is that the asteroids have been weathered in space, which changes their appearance,” says associate director of earth chemistry, Professor Trevor Ireland from the Australian National University.
The information retrieved may also help determine the link between meteorites and asteroids, Trevor says. “There’s nothing like going to the horse’s mouth, so-to-speak, and getting [samples] from the source. Any sample that comes back from Itokawa will be a major scientific find.”
Safe landing
Amazingly, the samples collected only need to be less than one thousandth of a gram. Dr Michael Zolensky is curator of stratospheric dust at NASA’s Astromaterials Research and Exploration Science directorate, says that up to a year could be spent studying just a tiny grain from the asteroid. “Our expertise in past missions tells us we don’t need to have much [in the] sample. Getting any kind of sample at all makes a mission a success; if we get five grains of sample that’s fantastic,” he says.
There are two items remaining on the list of achievements before the Hayabusa mission is completed: re-entry of the capsule into Earth’s atmosphere and study of the Itokawa sample in Japan. The team is cautiously optimistic about the landing. Leader of spacecraft systems at the JAXA Professor Hitoshi Kuninaka says that after the capsule’s retrieval the team will leave for Japan towards the end of next week, taking as much care as possible to avoid contamination of the samples.
The asteroid probe is set to touch down in Woomera on Sunday night, but it is likely only to be visible from the local area, JAXA scientists say. They have named a large basin on the asteroid the Woomera Desert in honour of the landing site.
LINKS
Hayabusa probe – JAXA
Itokawa – Wikipedia
