JAXA Press Release: "Venus Climate Orbiter AKATSUKI Inserted Into Venus' Orbit"
NASA Press Release: "NASA Scientists Applaud Japanese Spacecraft Akatsukis Successful Rendezvous with Venus"
The original mission plan was for an elliptical equatorial orbit with a 300 km apoapsis altitude and 80,000 km periapsis altitude. Now it's 400 km by 440,000 km. "Akatsuki should be able to accomplish most of its original science goals, although data will take longer to accumulate."
Spacefight Now:
The other 2 images:
"By Longwave IR camera (LIR) at around 2:19 p.m. on Dec. 7 (Japan Standard Time) at the Venus altitude of about 72,000 km"
These were images taken on December 9th, 2010 at 600,000 km away as part of a health check before the failed orbit insertion.
Left to right: ultraviolet imager (UVI), and 1 micron camera (IR1), long wave infrared camera (LIR). Images are artificially colored (UVI image - blue; IR1 image - red)
This image of Venus was captured by the Akatsuki spacecrafts Ultraviolet Imager (UVI), at around 12:19 a.m. EST (2:19 p.m. JST) on Dec. 7 at the Venus altitude of approximately 44,700 miles (72,000 kilometers).
NASA Press Release: "NASA Scientists Applaud Japanese Spacecraft Akatsukis Successful Rendezvous with Venus"
The nail-biting maneuver that sent Japans Akatsuki spacecraft into orbit around Venus this week is being celebrated by NASA scientists, eager to learn more about the atmosphere and climate of Earths enigmatic sister planet.
At about 7 p.m. EST on Sunday, Dec. 6, the Institute of Space and Astronautical Science (ISAS) of the Japan Aerospace Exploration Agency (JAXA) commanded the climate orbiter to fire four thrusters, aimed at nudging the spacecraft into orbit around Venus. About a half hour later, JAXA/ISAS announced that the small probe had successfully achieved an elliptical orbit around Venus.
A statement issued Wednesday from JAXA confirms the successful insertion, the good health of the spacecraft, and its present orbit. As a result of measuring and calculating the Akatsukis orbit after its thrust ejection, the orbiter is now flying on the elliptical orbit at the apoapsis altitude of about 400 kilometers and periapsis altitude of about 440,000 kilometers from Venus. The orbit period is 13 days and 14 hours. We also found that the orbiter is flying in the same direction as that of Venuss rotation."
While space exploration doesnt usually allow for second chances, Akatsuki got another shot at Venus after zipping past the planet on its first attempt in December of 2010, the result of a main engine failure during a crucial orbital-insertion burn. Akatsuki, which means dawn or daybreak in Japanese, spent five years orbiting the sun so it could catch up with Venus and try again.
Akatsuki is the first spacecraft to explore Venus since the European Space Agencys Venus Express reached the end of its mission in 2014.
NASAs Discovery program recently selected two Venus missions for further study, DaVinci and Veritas, which would complement Akatsukis scientific investigations.
The original mission plan was for an elliptical equatorial orbit with a 300 km apoapsis altitude and 80,000 km periapsis altitude. Now it's 400 km by 440,000 km. "Akatsuki should be able to accomplish most of its original science goals, although data will take longer to accumulate."
Spacefight Now:
Controllers activated three of Akatsukis five cameras before the spacecraft arrived at Venus, and JAXA published the first views from the imagers Wednesday. The probes other two cameras are scheduled to be switched on in the coming weeks.
The camera suite on Akatsuki, which is also named the Venus Climate Orbiter, includes two imagers to see Venus in two infrared wavelengths, a longwave infrared camera, an ultraviolet sensor, and an instrument to resolve potential lightning strikes in the Venusian atmosphere.
Each camera is designed to study a different part of the super-thick, sweltering atmosphere surrounding Venus and blocking camera views of its surface.
From far distances, we continually monitor the global-scale dynamics of the atmosphere and clouds, and of course, from close distances, we take close-up images of the atmosphere, the surface, and we also observe lightning and airglow when the spacecraft is in the shadow of Venus, said Takeshi Imamura, Akatsukis project scientist at JAXAs Institute of Space and Astronautical Science.
The mission will observe climate and weather conditions on Venus, looking at cloud patterns just above the surface and the super-rotating cloud structures that dominate the upper atmosphere. The ultraviolet camera will also track sulfur dioxide, a precursor to cloud formation at Venus.
Scientists hope to see the surface of Venus with one of Akatsukis infrared cameras in a bid to find active volcanoes. The cocoon of clouds around Venus prevents visible cameras from ever seeing through to the ground.
The data stream from Akatsuki could also hold clues on how clouds form on Venus, with measurements of sulfur dioxide a precursor to cloud formation water vapor and carbon monoxide.
Researchers also plan to measure radio waves transmitted through the planets atmosphere to measure its profile.
Akatsukis orbit is much farther from Venus than if the probe had entered orbit on time in 2010. The spacecrafts attitude control thrusters had enough power to steer Akatsuki into orbit, but only its main engine could take it closer to Venus.
Imamura said engineers have uploaded new software to Akatsuki to better see Venus from the spacecrafts higher-than-planned orbit, reducing the data volume coming back to Earth to streamline the missions scientific return.
By combining this information, we can model the three-dimensional structure of the atmosphere and the clouds, Imamura said.
Akatsukis ultraviolet camera, one-micron infrared imager and longwave infrared instrument are ready for observations, JAXA said Wednesday. The two-micron infrared camera, lightning detector and a radio oscillator for Akatsukis atmospheric profile measurements will be checked and put into operation now that the spacecraft is in orbit.
The missions ground team will guide Akatsuki closer to Venus over the next few months, eventually putting the probe in a nine-day orbit around the planet.
Regular observations are due to begin in April 2016, officials said.
The other 2 images:
"By 1μm camera (IR1) at around 1:50 p.m. on Dec. 7 (Japan Standard Time) at the Venus altitude of about 68,000 km"
"By Longwave IR camera (LIR) at around 2:19 p.m. on Dec. 7 (Japan Standard Time) at the Venus altitude of about 72,000 km"
These were images taken on December 9th, 2010 at 600,000 km away as part of a health check before the failed orbit insertion.
Left to right: ultraviolet imager (UVI), and 1 micron camera (IR1), long wave infrared camera (LIR). Images are artificially colored (UVI image - blue; IR1 image - red)