HAYABUSA CAPSULE RECOVERY BEGINS
By Jonathan Amos
Japanese scientists began the process on Monday of retrieving the Hayabusa capsule from the Australian Outback.
The cannister and its delivery spacecraft fell to Earth during the night, the culmination of a seven-year round trip to asteroid Itokawa.
The first photo of the capsule, which landed in the Woomera Prohibited Area, shows it still attached to a parachute.
The researchers will prepare the cannister for evacuation to Japan. They will hope it holds samples of Itokawa.
If that is confirmed, it would be the first time fragments of rock had been picked up off the surface of an asteroid and returned to Earth.
But scientists caution it could be some weeks before they are able to confirm the presence of Itokawa dust. For the moment, the Japanese space agency (Jaxa) is simply celebrating the success of bringing Hayabusa home.
The re-entry produced a remarkable fireball in the Australian sky. The main spacecraft broke apart in a shower of light. As these bright streaks faded, a single point could be seen heading to the ground. This was the capsule protected against the intense heat generated in the fall by its carbon shield.
It took about an hour to locate the capsule by helicopter, its position tracked by radar and a beacon that was transmitting from inside the cannister. It was only when daylight came up on Monday that recovery teams began to approach the capsule.
“We will package the capsule and then send it back by aircraft – it's a special aircraft – from the Woomera range to Tokyo International Airport, to go to our facility, our laboratory, where we will analyse the samples,” Yoshiyuki Hasegawa, the associate executive director of Jaxa, told BBC News.
Even now, there is still some uncertainty as to whether the capsule really does contain pieces of Itokawa.
Analysis has shown the Hayabusa spacecraft's capture mechanism malfunctioned at the moment it was supposed to pick up the asteroid rock fragments.
However, Japanese space agency (Jaxa) officials remain confident of success.
They say a lot of dust would have been kicked up when Hayabusa landed on the space rock to make the grab, and some of this material must have found its way inside the probe.
“You hope for grams of sample but you can make do with much less than that,” observed Dr Michael Zolensky who worked on Nasa's Stardust comet sample-return mission.
“On Stardust, the entire sample return was on the order of thousands of nano-grams. That was thousands of grains, each of which weighed about one nano-gram; and one of those grains you could spend a year studying,” he told BBC News.
Such grains would provide new insight into the early history of the Solar System and the formation of the planets more than 4.5 billion years ago.
Professor Ireland said no rocks on Earth could provide this information because they had been recycled many times.
“If we look at anything on Earth it has been thoroughly through the wringer; it's been messed up by plate-tectonic processes and geochemical processes. So if we want to look at what our Earth was made of, we have to leave Earth. That's the importance of Hayabusa and going to Itokawa.”
ASTEROID 25143 ITOKAWA – A 'PILE OF RUBBLE'
Hayabusa returned astonishing images from its encounter with Itokawa
The 500m-long Itokawa has many boulders covering its surface
The biggest is 50m wide; it is nicknamed 'Yoshinodai'
Observations revealed Itokawa's density to be extremely low
Scientists say it is a pile of rubble that was produced in a collision
Gravity would have collected the debris into the object we now see