Japanese spacecraft reaches Venus — five years late

Akatsuki finally arrives at its destination after a detour around the sun

illustration of Akatsuki spacecraft

BETTER LATE THAN NEVER Five years after an engine misfire, the Akatsuki spacecraft (illustrated) just got a second chance at orbiting the planet Venus.

JAXA

After missing a turn off the interplanetary expressway, a spacecraft has now finished taking the scenic route to Venus. The Japan Aerospace Exploration Agency Akatsuki probe successfully went into orbit around Earth’s sister planet at 8:51 a.m. December 7 Japan Standard Time — only five years after its first attempt.

Akatsuki has been looping around the sun since 2010, after an engine misfire prevented the spacecraft from slowing down enough to be captured by Venus’ gravity. A nudge from its remaining thrusters put the probe on an orbit that would bring it back to Venus in five years. With its main engine offline and the planet in sight, Akatsuki relied on small attitude control thrusters to slow it enough during this year’s encounter to stay for an extended visit.

The original plan was to spend two years at Venus, studying the planet’s meteorology and mapping the surface. Now, mission engineers may have to revise that plan. Akatsuki is stuck on a highly elliptical orbit around the planet and it got a little cooked during a journey that brought it closer to the sun than intended. 


This post was updated on December 23, 2015, to clarify the adjustments made for the probe’s rendezvous with Venus.

Christopher Crockett is an Associate News Editor. He was formerly the astronomy writer from 2014 to 2017, and he has a Ph.D. in astronomy from the University of California, Los Angeles.