This post is a little delayed, but I hope it will still be welcome because the news is good: Japan's Akatsuki Venus orbiter is well into its science mission, and has already produced surprising science results. Project manager Masato Nakamura presented first results at the International Venus Conference in early April; his presentation was summarized in detail by Elizabeth Gibney for Nature News. The mission also posted a very detailed presentation about mission status and early science results dated March 31 (PDF). Since then, an unmannedspaceflight.com user who goes by "pandaneko" has been doggedly translating the text on all of the slides.

This post summarizes his translations, with a little additional help from Gibney's article. Numbers in brackets refer to specific presentation slides as translated by pandaneko. Any errors are mine, and I welcome corrections in the comments.

Akatsuki entered orbit on December 7, 2015. Following an orbit correction on December 20, Akatsuki was placed successfully into the orbit planned for its redesigned science mission. As of March 31, 2016, it had already achieved the minimum success criteria of that new mission, and they are now working toward achieving the goals of the research plan outlined for Akatsuki before its launch. The current orbit is highly elongated, so most of Akatsuki's images are lower-resolution than intended, but this is partially compensated by the fact that Akatsuki is able to observe continuously for a long period. [4]

What, exactly, are Akatsuki's science goals? It's intended to study Venus' atmospheric dynamics; of particular interest is the mechanism that drives the super-rotation of Venus' atmosphere. (Venus rotates extremely slowly, but its entire atmosphere moves around the planet once every four days.) Akatsuki carries 5 science instruments that see in different parts of the electromagnetic spectrum. Different wavelengths penetrate to different depths in Venus' thick, cloudy atmosphere, so by viewing Venus in different wavelengths, Akatsuki sees Venus' atmosphere at different elevations. [5]