Particles brought back by Japan’s Hayabusa unmanned space probe, which returned to Earth from the asteroid Itokawa last June, show signs that the material constituting the asteroid may have been formed in high temperatures at the time the solar system was created 4.6 billion years ago, the Japan Aerospace Exploration Agency, or JAXA, said in a preliminary analysis report Thursday.
The agency also said organic substances, which could help explain the origins of life, have not been found in the samples.
JAXA has been examining the particles in cooperation with scientists across the country, with the hope of shedding light on the origin of the solar system, as Itokawa is said to have maintained its form from the time the solar system was created.
A team of scientists flew to the Australian Outback on Monday to recover a Japanese space capsule they hope contains the first-ever asteroid samples that could provide clues into the creation of the solar system.
The Hayabusa explorer returned to Earth overnight after a seven-year, 4-billion mile (6-billion kilometer) journey, burning apart on re-entry in a spectacular fireball just after jettisoning the capsule. It was the first time a spacecraft successfully landed on an asteroid and returned to Earth.
NASA scientist Scott Sandford said it was a relief to watch the re-entry and see the capsule had successfully detached and parachuted to Earth.
“During a mission critical event like a re-entry, there’s a whole series of things you’ve got to get right to make it work, and they all seemed to have come off without a hitch,” said Sandford, an astrophysicist and one of the team members who will research the samples. “It’s a great testament to the design and operation of the spacecraft.”
Japanese engineers have devised a plan to combine parts from two partially-failed ion engines to resume the Hayabusa asteroid probe’s journey back to Earth.
In a press release Thursday, officials said they will use the neutralizer of Thruster A and the ion source of Thruster B to provide enough power to guide the 950-pound spacecraft home next June.
Hayabusa launched in 2003 with four ion engines. Thruster A was shut down due to instability shortly after launch, while Thruster B was turned off after high voltage in its neutralization system.
Thruster C was manually switched off after signs it might be damaged by high electrical currents, and Thruster D failed two weeks ago due to a voltage spike.
The Nov. 4 glitch left Hayabusa without a propulsion system and put its scheduled return to Earth in serious doubt. But the new plan gives Japanese officials new hope.
“While the operation still needs monitored carefully, the project team has concluded the spacecraft can maintain the current return cruise schedule back to the Earth around June of 2010, if the new engines configuration continues to work as planned,” the Japan Aerospace Exploration Agency said in a statement.
Hayabusa’s four experimental microwave discharge ion engines consume xenon gas and expel the ionized propellant at high speeds to produce thrust. Ion engines are more efficient than conventional chemical thrusters because they use less fuel and can operate continuously for thousands of hours.
The craft’s thrusters have accumulated almost 40,000 hours of burn time since the probe launched.
Plans call for the spacecraft to continue thrusting until March, when it will shut down the ion system and coast toward Earth for a parachuted landing in Australia.