But the astronauts had more immediate issues to deal with. At one point they passed over Florida, which has been getting heavy rain for several days. The weather forecast for Friday, the shuttle's scheduled landing day, is not much better, and it's still unlikely to be clear on Saturday.
As a result, mission control has told the astronauts to turn off unnecessary lights and computers to save electricity. If landing is delayed, as has happened on many missions before, the crew will have more down time up there than they expected.
It is actually easier to keep the astronauts in space for a few extra days than to land at Edwards Air Force Base in California -- where the weather is fine, but it costs $1.8 million to ship the shuttle back to Florida for its next launch.
"I never imagined that the flight would go as, uh, interestingly as it has," said commander Altman.
The astronauts may not mind. Dan Barry, who left NASA in 2005, tells of turning on music and dancing, weightless, with crewmates.
"You can actually play Quidditch in space," he said. "No brooms, but I brought a ball, and we chased it, and bounced off each other as it sailed past us."
Astronauts keep such adventures going -- until mission control notices the whole space vehicle moving because of the acrobatics inside.
"You do these magical things," said Barry. "And you do this with incredible joy."