Tomorrow’s the big day. After spending more than two years hanging out with comet 67P/Churyumov-Gerasimenko, the European Space Agency’s Rosetta space probe will end its mission with a literal bang — a final firing of the engines, a long controlled descent, and finally a crash onto the surface of the comet, never to be heard from again.

It’s a fitting end for the spacecraft, the first ever to accompany a comet on its journey around the sun. The mission included the spectacular feat of successfully sending the Philae Lander to the comet’s surface, providing Earthling scientists with incomparable images of this ancient piece of space junk. Philae went dark and woke up again, was lost and found, and was mourned with great sincerity. Now it’s time to say goodbye to the mothership, too.

Rosetta’s kamikaze mission should provide some of the most exciting data from the trip to date, and scientists will be working furiously to downlink as much information as possible before the transmission goes dark. The space probe could not be safely kept alive as the comet travels farther and farther from the sun, and this plan offers a dramatic and scientifically valuable end to a pioneering mission.

Space fans will be on the edge of their seats beginning later today and all through the night, though the real excitement will start after 6 a.m. EST Friday morning. That’s early, but seriously — you’ll be witnessing a motherflippin space probe crash into a comet.

ESA plans to execute the collision manoeuvre just before 5 p.m. EST Thursday. This will set the probe in a free fall towards the comet, from about 12 miles up. Images of the descent will be available as they come in, from perhaps 8 p.m. onwards, on the space agency’s image database and on Twitter.

Scientists will be monitoring the descent carefully, and final commands to the probe will be sent at about 4 a.m. EST Friday. This will fine tune the descent path, and allow for a more precise estimate of landing time, currently scheduled for 6:40 a.m. The ESA will live-stream a brief update when that information is available.

The European Space Agency’s live stream of the final descent begins at 6:30 a.m. Because of the transmission delay, the end of the mission will be confirmed 40 minutes after the actual impact. Visit the ESA website for full coverage details.

NASA Television will provide its own live stream of Rosetta’s last moments, from 6:15 to 8 a.m. EST Friday, with commentary from U.S. scientists involved with the mission. NASA contributed several instruments to the Rosetta space probe and collaborated on the Philae Lander. More details on the space agency’s coverage are available through its website.

Photos via ESA/ATG medialab