ESA's comet-chasing Rosetta spacecraft is nearing the end of its mission. The spacecraft depends on the Sun for power, and had energy to spare when the comet was at perihelion (of about 1.24 AU) on August 13. But the comet has spent the last year rapidly receding from the Sun: it's already nearly at 3.5 AU, beyond the main asteroid belt. So Rosetta's power is declining, with the Sun already 8 times less strong than it was at perihelion. Rosetta survived to great distance from the Sun earlier in its mission only by entering a deep hibernation. ESA isn't going to try that hibernation feat again, and is instead planning to end the mission with a slow spiral into the comet and a controlled impact on September 30.

Last week, ESA announced when and where Rosetta is going to touch down, bringing the mission to an end: within the Ma'at region on the comet's head, at approximately 10:30 UTC (12:30 CEST / 06:30 EDT / 03:30 PDT) on September 30. It took me a while to figure out its position relative to the Philae landing locations -- comet geography is challenging! -- but I think this is how they all relate to each other: