In May 2010, Japan’s Aerospace Exploration Agency (JAXA) launched the "Planet C" spacecraft – also known as "Akatsuki" or the Venus Climate Orbiter – towards Earth's "sister planet". The early stages of the mission did not go as planned. On its approach to Venus in December 2010, the spacecraft was supposed to decelerate with a controlled burn to place it in orbit. But due to a malfunction with the main engine, the planned 12-minute burn lasted just three, and Planet C shot well past its target instead.

That could have been the end of it, but JAXA was able to use the spacecraft's auxiliary reaction control system to adjust its trajectory and slow it down as it orbited the Sun. Five years later, the space agency announced that they had finally put the probe around Venus, and work could begin.

“As a result of measuring and calculating the Akatsuki’s orbit after its thrust ejection, the orbiter is now flying on the elliptical orbit at the periapsis altitude of about 400 kilometers and apoapsis altitude of about 440,000 kilometers from Venus," the space agency announced in 2015. "The orbit period is 13 days and 14 hours. We also found that the orbiter is flying in the same direction as that of Venus’s rotation.”

Soon after that, the spacecraft began returning its first photographs and data, helping us to study the atmosphere of Venus. Though not in its original planned orbit, the orbit it ended up in was advantageous.
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"Communication with 'Akatsuki' was lost during operations near the end of April 2024, triggered by an incident in a control mode of lower-precision attitude maintenance for a prolonged period," JAXA explained in a statement.

"Although recovery operations were conducted to restore communication, there has been no luck so far. Considering the fact that the spacecraft has aged, well exceeding its designed lifetime, and was already in the late-stage operation phase, it has been decided to terminate operations."