Yesterday was a frustratingly long day in space as Atlantis astronauts struggled to fix a long-broken spectrograph on the Hubble Space Telescope. They ultimately succeeded, but a stuck bolt and dead battery prolonged the spacewalk to 8 hours—making it the sixth longest in history, Space.com reports. Astronauts also ran out of time to insulate Hubble, but may attempt to do so on today's fifth and final spacewalk.
Astronaut Michael Massimino ripped his spacesuit glove during yesterday's fixes, but was not in any danger. The spectrograph—which doubles as a camera, detects black holes, and discerns the chemical makeup of the atmosphere—was never designed to be repaired in orbit. The fixed machine failed after initial tests, but mission engineers plan to test it again after it warms up.