After a year-long hiatus, we have a robotic explorer around our angry, overheated twin of a planet again! Late last night the Japanese Space Agency confirmed their audacious plan to use manoeuvring thrusters worked, and now the spacecraft is already sending home new photos.
When the Japanese spacecraft Akatsuki attempted to go into orbit around Venus in 2010, its engine malfunctioned and it missed. Hurtling into space without main engines, the spacecraft appeared doomed. But clever trickery by the engineering team led to a plan to use smaller manoeuvring thrusters to slowly nudge into orbit instead. It took five years to be back in position, but on Sunday night it made a valiant last-ditch effort to get into orbit around Venus and salvage its mission.
Venus in ultraviolet from 1.1 million kilometres away. Image credit: JAXA
We knew right away that the jets fired as scheduled, but it took until today to be certain that the change in velocity was enough to get Akatsuki into orbit. After carefully observing telemetry and orbital velocity, the Japanese space agency JAXA confirms the spacecraft is in a higher orbit around Venus than the original plan five years ago, but it's in orbit. After the next nine days of adjustments, Akatsuki's orbit will range from 310,000 to 340,000km away from the planet, which is higher than ideal for the instruments but thanks to over-performance of the thrusters over the weekend, in a closer, better orbit than anticipated from the salvage
The first photographs returned from the orbiter are of the planet in ultraviolet captured at the start of orbital insertion. The image captures Venus's wild clouds, along with the upward diffusion of sulphur dioxide (SO2 ) from atmospheric circulation. It appears that at least three of five instruments are working perfectly with no degradation despite being well outside their intended lifespan. Akatsuki was designed to spend six months (not five years, six months!) travelling to Venus before starting two years of observations.
This accomplishment is incredible not just because Venus is tragically under-studied, but because of the ingenuity and persistence of the JAXA team in figuring out how to salvage their wayward spacecraft. Congratulations to everyone involved, and we are thoroughly, delightfully impressed!
Top image: Now that's the cutest little mission control station ever! Credit: JAXA
Appreciation to @5thstar, a space journalist providing excellent technical translations.