The World

10 ESSENTIAL STORIES

1 | Florida A Final, Perilous Tune-Up The space shuttle Atlantis is on a last maintenance mission to the aging Hubble Space Telescope before its replacement, the James Webb Space Telescope, takes to the skies in 2014. It's a risky assignment: the Hubble's 350-mile-high orbit is clotted with fast-moving "space junk" that could damage the craft. With the International Space Station out of reach, a second shuttle, Endeavour, is ready to fetch the crew in case of an emergency.

Celestial Sightseers: Hubble vs. Webb

[This article contains a table. Please see hardcopy of magazine or PDF.]

HUBBLE WEBB ORBIT 353 miles...

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