Selene blasts off for the Moon
Sep 14, 2007
The most sophisticated spacecraft to study the Moon in more than 30 years was launched today by JAXA, the Japanese Aerospace Exploration Agency. Called Selene, the mission will help scientists understand the Moon’s origin and evolution, and possibly even locate a site for a future lunar base. The spacecraft blasted off at 10:31 am local time (2:31 am BST) from the Japanese island of Tanegashima, and if successful it will help restore confidence in JAXA, which has suffered a series of failed missions in the past few years.
45 minutes after launch, JAXA confirmed that the $484m spacecraft separated from its rocket and then orbited Earth twice before starting its journey to the Moon. Once there, it will separate into a main orbiter, which will observe the Moon from a 100-km circular orbit for one year, and a small “VRAD” satellite that will measure the Moon’s gravitational field from an 800-km elliptical orbit. A third small satellite will assist VRAD’s measurements from a distant 2400-km elliptical orbit and relay data from the main orbiter to Earth.
In total, Selene has 15 different observation missions. These range from recording the different elements and minerals on the Moon’s surface using spectrometers and infrared imagers, to mapping the larger topographical structure using a stereo camera, radar and a laser altimeter. The mission will also investigate environmental properties of the Moon such as its magnetic field, and see how Earth’s ionosphere and magnetosphere look from the Moon’s perspective. Finally, Selene will use a high-definition camera to make a film of the Earth rising from the Moon’s horizon.
JAXA hopes that the spacecraft will put Japan at the front of lunar exploration and possibly even help plan for a manned moon base around 2030. However, the agency will have to shake memories of several failed space missions. Earlier this year JAXA’s Lunar-A spacecraft was scrapped because of worries that an aging mothership would jeopardize the mission. In 2005 the Hayabusa spacecraft, which was designed to fetch rock samples from an asteroid, failed because of thruster problems. Prior to that, JAXA had to destroy a rocket carrying spy satellites when it veered off course after lift-off.
Still, if all goes to plan, Selene will carry out the most wide-ranging study of the moon since NASA’s Apollo programme of the 1960s and 1970s and will keep Japan ahead of China and India, which plan to launch lunar missions over the next year.
About the author
Jon Cartwright is a reporter for physicsworld.com