Top 10 NASA Flubs

Even as NASA welcomes home the crew of one its final shuttle missions (just two days after commemorating the 40th anniversary of the miraculous return of the Apollo 13 crew), it's grappling with how to adapt to a new President's plan for its future. TIME takes a look at the dimmer moments in its history: the canceled projects, the failures and some notable mishaps

The Mars Observer

Top 10 NASA Flubs

NASA

If there are Martians, they were probably laughing on Aug. 21, 1993. That's the day the Mars Observer went missing, vanishing into thin air (or rather, no air). The spacecraft had launched a year earlier, but contact was lost days before it was supposed to enter the Red Planet's orbit. At NASA's Jet Propulsion Laboratory, some comforted themselves by putting a milk carton with a picture of the spacecraft and the words "Have You Seen Me?" on the wall.

Read "The Mars Rovers' Long and Fruitful Journeys."

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