Thursday was a great day for the astronauts working on the Hubble Space Telescope. But …. I have to tell you, it wasn’t all easy.

The highest priority for this service mission to the Hubble was to replace the Wide Field Planetary Camera 2 with a new one, the Wide Field Planetary Camera 3.

In order to put the new one in, the astronauts first had to take the old one out. But …. things were not going according to plan at one point. Watch the video and see how calm and professional astronaut Drew Feustal is in the face of a stuck bolt that could ruin the highest priority of the entire mission…