High Stakes for Hubble: Atlantis Astronauts' Risky Mission

Astronaut Andrew Feustel, left, navigates near the Hubble Space Telescope on the end of the remote manipulator system arm. Astronaut John Grunsfeld, right, signals to his crew mate from just a few feet away. Astronauts Feustel and Grunsfeld were continuing servicing work on the giant observatory, locked down in the cargo bay of the shuttle. (NASA/AP Photo )