Akatsuki

Also known as PLANET-C, Venus Climate Orbiter

defunct Venus orbiter operated by JAXA

Key facts

Names: Venus Climate Orbiter (VCO), PLANET-C
Mission type: Venus orbiter
Operator: JAXA
Cospar id: 2010-020D
Website: JAXA , JAXA Special Site
Mission duration: 13 years, 11 months
Manufacturer: NEC Space Technologies
Launch mass: 517.6 kg (1,141 lb)
Dry mass: 320 kg (710 lb)
Dimensions: 1.04 × 1.45 × 1.44 m (3.4 × 4.8 × 4.7 ft)
Power: >700 watts at 0.7 AU
Launch date: 21 May 2010, 21:58:22 ( 2010-05-21UTC21:58:22Z ) UTC

~18 min read

Article

Akatsuki (あかつき, 暁; "Dawn"), also known as the Venus Climate Orbiter (VCO) and Planet-C, was a Japan Aerospace Exploration Agency (JAXA) space probe tasked with studying the atmosphere of Venus. It was launched aboard an H-IIA 202 rocket on 20 May 2010, but failed to enter orbit around Venus on 6 December 2010. After the craft orbited the Sun for five years, engineers successfully placed it into an alternate Venusian elliptic orbit on 7 December 2015 by firing its attitude control thrusters for 20 minutes, making it the first Japanese satellite to orbit Venus.

By using five different cameras working at several wavelengths, Akatsuki studied the stratification of the atmosphere, atmospheric dynamics, and cloud physics. Astronomers working on the mission reported detecting a possible gravity wave (not to be confused with gravitational waves) in Venus's atmosphere in December 2015.