Akatsuki probe near Venus orbit

Tuesday, Dec. 7, 2010

Space agency officials plan to have craft study planet's atmosphere for more than two years

Kyodo News

The Japanese space probe Akatsuki is expected to enter the orbit of Venus on Tuesday, 200 days after it was launched from Earth in May, JAXA officials said Monday.

Entering orbit: The space probe Akatsuki approaches Venus in a computer rendering provided by the Japan Aerospace Exploration Agency. KYODO PHOTO

Akatsuki, which would be the first Japanese space probe to orbit a planet other than Earth, successfully rotated its engine in the direction its traveling shortly before 8 a.m. Monday, according to JAXA, the Japan Aerospace Exploration Agency. When the probe is about 550 km above Venus around 9 a.m. Tuesday, it will fire its engine for 12 minutes to slow down enough to enter the planet's orbit.

Because signals take about three minutes and 30 seconds to reach the probe, which will be about 63 million km from Earth, it will make adjustments according to instructions previously sent.

"The probe will have only one chance (to enter orbit). If it fails, it will pass over Venus," said Masato Nakamura, a JAXA project manager.

Once the probe enters orbit, it will make two adjustments to achieve its targeted orbital altitudes of 550 km to 80,000 km around Dec. 13. It will then observe the atmosphere of the planet for more than two years using various instruments, including those that measure near-infrared and ultraviolet rays.

Akatsuki was developed at a cost of ¥25.2 billion for Japan's first planetary exploration mission since the unsuccessful Mars probe Nozomi, which was launched in 1998 but failed to enter orbit due to technical glitches.