Space shuttle Atlantis rocketed into orbit on Monday with six astronauts and a full load of spare parts for the International Space Station.
The supply run should keep the space station humming for years to come, and the shuttle astronauts in space through Thanksgiving.
Atlantis shot into a partly cloudy sky at 2:28 pm (1928 GMT), to the delight of about 100 Twittering space enthusiasts who won front-row seats at Cape Canaveral.
It was NASA's first launch "tweetup," and the invitees splashed news - mostly tweeting "wow" about the liftoff - over countless cell phones and computers.
Atlantis will reach the space station on Wednesday.
As the shuttle blasted off, the station was soaring 220 miles (350 kilometres) above the South Pacific.
NASA wants to stockpile as many pumps, tanks, gyroscopes and other oversize equipment as possible at the space station, before the three remaining shuttles retire next autumn.
None of the other visiting spacecraft is big enough to carry such large pieces.
The space agency expects to keep the space station flying until 2015, possibly 2020 if President Barack Obama gives the go-ahead.
During their 11-day flight, Hobaugh and his crew - including the first orthopaedic surgeon in space, Dr. Robert Satcher Jr. - will unload the nearly 30,000 pounds (13,600 kilogrammes) of equipment and experiments.
Most of the gear will be attached to the outside of the space station on storage platforms.
Three spacewalks will be conducted beginning on Thursday to hook everything up and get a jump on the next shuttle flight.
If all goes as planned, the six spacemen will return to Earth the day after Thanksgiving, bringing home a seventh astronaut, Nicole Stott, who has been living at the space station since the end of August.