[meteorite-list] Japan Nears Launch of Hayabusa 2 Probe to Retrieve Asteroid Samples
From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Tue, 2 Sep 2014 09:06:16 -0700 (PDT)
Japan nears launch of probe to retrieve asteroid samples
BY STEPHEN CLARK
September 1, 2014
The Hayabusa 2 asteroid probe, on track for liftoff this winter, will
be shipped to its island launch base at the end of September for final
preparations to start the most audacious space exploration mission ever
attempted by Japan.
The mission will take off on top of an H-2A launcher as soon as December,
fly to an asteroid scientists believe is a relic from the genesis of the
solar system, drop a European-built lander, and return to Earth in 2020
with extraterrestrial rock samples.
The Japan Aerospace Exploration Agency revealed Hayabusa 2 to media Sunday
as it neared the finish line in a four-year effort to design, construct
and test the spacecraft.
Japanese officials have not announced the target launch date, but they
say the mission is on schedule to lift off as soon as December in a narrow
window when Earth and Hayabusa 2's target asteroid are properly positioned
to make the journey possible.
Backup launch windows are available in June and December 2015.
The spacecraft, now almost fully assembled for flight, will soon wrap
up testing at JAXA's Sagamihara campus near Tokyo, according to Hitoshi
Kuninaka, Hayabusa 2's project manager.
"At the end of September, the spacecraft will be transported to Tanegashima,"
Hayabusa 2's launch is next in line for liftoff from the Tanegashima Space
Center -- located on Tanegashima Island in southwestern Japan -- after
an Oct. 7 launch of the Himawari 8 weather satellite.
Once the spacecraft arrives at the launch site, Kuninaka said technicians
will install pyrotechnic charges for its mission, which include explosives
to excavate material from beneath the asteroid's surface. Ground crews
will also add the mission's flight batteries and fill the probe with xenon
gas and hydrazine propellant.
JAXA says the Hayabusa 2 mission's cost is 28.9 billion yen, or about
Hayabusa 2's launch follows four years after its namesake -- the hard-luck
Hayabusa mission -- returned to Earth with microscopic specimens collected
from asteroid Itokawa.
Engineers designed Hayabusa with upgrades to expand its scientific payoff
and increase its chance for success.
Hayabusa 2 carries four xenon-fueled ion thrusters for the voyage to asteroid
1999 JU3, an object with a diameter of about 3,200 feet that researchers
believe is made of primitive rock left over from the ancient solar system.
After a swingby of Earth in late 2015 to get a gravity boost, the 1,320-pound
craft will arrive at 1999 JU3 in June 2018 and loiter around the asteroid
for about 18 months.
Once it arrives at asteroid 1999 JU3, Hayabusa 2 will survey the rock
with an array of instruments, including imagers, a spectrometer, and a
The craft will also release a small Japanese rover named MINERVA to hop
across the surface of the asteroid and deploy the MASCOT lander developed
by the German Aerospace Center, or DLR.
Hayabusa spent about three months exploring Itokawa, an asteroid about
half the size of 1999 JU3.
Hayabusa 2's destination is a different type of miniature world than Itokawa.
Asteroid 1999 JU3 is a C-type asteroid, a classification of primitive
objects made of organic and hydrated minerals.
Itokawa is an S-type asteroid composed of rocks and metals heated and
modified over the solar system's 4.5 billion year history, causing the
material to lose chemical markers left over from the dawn of the solar
Scientists expect the Hayabusa 2 samples to hold a record of the tumultuous
early phases of the solar system's formation, including the basic building
blocks of life such as amino acids.
Hayabusa 2 will collect up to three samples from 1999 JU3, including material
blasted from beneath the asteroid's surface by a explosive grapefruit-sized
copper impactor released from the mothership.
Depending on the texture of the rocks on 1999 JU3, Hayabusa 2 should pick
up between a gram and several grams of samples.
After up to three close approaches to acquire samples, Hayabusa 2 will
depart the asteroid in December 2019 and deploy a sample-bearing re-entry
capsule into Earth's atmosphere in December 2020.
Received on Tue 02 Sep 2014 12:06:16 PM PDT