EXPLORE


JOINRENEWJOIN

30th Anniversary of The Planetary Society
  

Space Topics

Akatsuki (Venus Climate Orbiter / PLANET-C)


How did Venus and Earth, near-twins in size and composition and neighbors close to the Sun, grow up to be such different planets? Answering that question is the goal for JAXA's Akatsuki mission, also known as Venus Climate Orbiter or PLANET-C. Akatsuki's investigations will focus on Venus' dense, super-rotating atmosphere, a dense mass of carbon dioxide containing high-altitude clouds of sulfuric acid.

Akatsuki is stacked on a single launch vehicle with IKAROS, JAXA's solar sail.

Akatsuki bears six science instruments, five of which are cameras that explore Venus in wavelengths from ultraviolet to the mid-infrared:
  • Lightning and airglow camera (LAC): looks for lightning in visible wavelengths (552 to 777 nanometers)
  • Longwave infrared camera (LIR): studies the structure of high-altitude clouds at a wavelength where they emit heat (10 microns)
  • Ultraviolet imager (UVI): studies the distribution of specific atmospheric gases such as sulfur dioxide in ultraviolet wavelengths (293 to 365 nanometers)
  • 1-micron camera (IR1): peers through semitransparent windows in Venus' murky atmosphere to see heat radiation emitted from Venus' surface rocks (0.9 to 1.01 microns); could spot active volcanoes, if they exist
  • 2-micron camera (IR2): peers through semitransparent windows in Venus' atmosphere to see heat radiation emitted from the lower reaches of the atmosphere (1.65 to 2.32 microns)
The last science instrument is its radio dish, which will be used to actively probe the atmosphere.

The spacecraft is a box 1.04 by 1.45 by 1.4 meters in size with two solar paddles. At launch time it will weigh 500 kilograms.

Akatsuki Facts:
Launch: May 17, 2010 21:44:14 UTC (May 18, 2010 at 06:44:14 JST)
Venus arrival: December 2010
Orbit: Elliptical (300 by 80,000 km), equatorial, 30-hour period
Nominal mission end: 4 years after launch