Asteroid flyby complete
2008-09-06 20:04
Darmstadt - A deep space probe launched by the European Space Agency successfully completed a flyby of an asteroid millions of kilometres from Earth on Friday.
Rosetta rendezvoused with the Steins asteroid, also known as Asteroid 2867 - currently in the asteroid belt between the orbits of Mars and Jupiter - just after 20:45 on Friday at a distance of just less than 805 kilometres.
As planned, the spacecraft lost signal for about an hour and a half, as engineers turned it away from the sun and because the craft was moving too fast for its antennae to transmit any signal.
At 22:14, the craft resumed signal transmission to the cheers of Esa engineers and technicians.
"We're extremely happy that it worked," said the mission's manager Gerhard Schwehm, sipping a glass of champagne after the announcement from the control room.
"It's a big relief. People can relax a bit now and everything seems fine."
The images and data from the deep space craft - which was launched in March 2004 from French Guyana, and is 402 million kilometres from Earth - have begun beaming back to the earth.
Minor glitch
Schwehm said the agency would work to get the data and images processed as soon as possible, but said there was a minor glitch.
He said the data must first be sent to antenna stations far away from Europe because of signal issues created by the present position of the satellite and the curvature of the earth.
One of those stations, a Nasa laboratory in Goldstone, California was having issues cooling one of its antennae on Friday, and was forced to switch the Esa project to another of its antennae.
That switch would delay the analysis of some of the data until 01:00 German time, but Schwehm said that probably wouldn't affect the release of the images to the world on Saturday.
The other antenna station where Rosetta data is streaming is in New Norcia, near Perth, Australia.
"The operation went very well," said Paolo Ferri, the head of the solar and planetary missions division and Rosetta flight operations director in a short speech after the announcement.
"The spacecraft is in exactly the condition we expected, which is good. All indications are that everything was super successful."
Unlocking the mysteries
The timing of the flyby ensured the asteroid would be illuminated by the sun, making it likely the transmitted images will be clear and sharp. Experts will parse the data from the 4.6 kilometre-diameter irregularly shaped asteroid for keys that could help unlock some of the mysteries of the creation of the solar system.
"Dead rocks can say a lot," Schwehm said.
Astronomers have had to work with limited data from brief flybys, such as when Esa's Giotto probe swept by Halley's Comet in 1986, photographing long canyons, broad craters and 3 000-foot hills.
Steins is Rosetta's first scientific target as it makes its incursion into the asteroid belt located between the orbits of Mars and Jupiter en route to its destination, the comet 67/P Churyumov-Gerasimenko, which is scheduled for 2014. Between now and then it will do some gravitational experiments and then go into hibernation, Esa said.
- AP