Want to stay on top of all the space news? Follow @universetoday on TwitterHayabusa was an unmanned spacecraft designed and developed by the Japan Aerospace Exploration Agency(JAXA). Its mission was to return a sample from the near Earth asteroid 25143 Itokawa for analysis. The spacecraft was launched on May 9, 2003 with rendezvous taking place in September 2005. After arriving at the asteroid, Hayabusa studied its shape, spin, topography, color, composition, density, and history. In November 2005, it landed(the landing was accidental as the craft was supposed to hover a few meters above the surface) on the asteroid and collected tiny grains of accreted material from the asteroids surface. The samples were successfully returned to Earth on June 13, 2010. The spacecraft also carried the detachable mini-lander MINERVA, which failed to deploy correctly.
The spacecraft used four xenon ion engines, which operated on a near continuous basis for two years to maneuver itself toward Itokawa. Upon arrival the spacecraft entered a station-keeping heliocentric orbit close to the asteroid. This orbit was used to survey the surface from a distance of about 20 km. The spacecraft then moved closer and then approached the asteroid for a series of soft landings and the collection of samples. Autonomous optical navigation was used during this period because of the long communication delay from Earth. During the second touchdown, the spacecraft fired tiny projectiles at the surface and collected the resulting spray for analysis back on Earth.
After a few months in proximity to the asteroid, the spacecraft was scheduled to fire its engines to begin its cruise back to Earth. This maneuver was delayed due to problems with attitude control and the thrusters of the craft. The attitude issue was resolved by firing a xenon engine and the craft began its journey back to Earth. Once it was on its return trajectory, the re-entry capsule was released from the main spacecraft three hours before reentry. The capsule coasted on a ballistic trajectory, re-entering the Earth’s atmosphere on June 13, 2010.
In regards to the MINERVA lander, an error during deployment resulted in the craft’s failure. The vehicle was designed to take advantage of Itokawa’s very low gravity through the use of an internal flywheel assembly to hop across the surface, relaying images from its cameras. It was deployed on November 12, 2005, but before the release command could arrive, Hayabusa had started an automatic altitude keeping sequence. As a result, MINERVA was released while the probe was ascending and it escaped Itokawa’s gravitational pull and tumbled into space.
The material returned from the mission provided several findings. Analysis of the dust from Itokawa suggested that it most likely had been part of a larger asteroid many millions of years ago. The collected material appeared to have been exposed for about eight million years. It was also found to be consistent with material found in meteorites.
We have written many articles about Hayabusa for Universe Today.
Subaru Telescope Takes Montage of Hayabusa’s Return to Earth
Confirmed: Hayabusa Nabbed Asteroid Particles
If you’d like more info on Hayabusa, check out these articles:
JAXA: Asteroid Explorer “Hayabusa”
Hayabusa Spacecraft Returns Asteroid Artifacts from Space
We’ve also recorded an entire episode of Astronomy Cast all about Asteroids. Listen here, Episode 29: Asteroids Make Bad Neighbors.