The space shuttle Discovery sits atop the launch pad before the overnight launch was cancelled. (Scott Audette/Reuters)NASA delayed a planned night launch of the space shuttle Discovery early Tuesday because of rain and lightning near the launch site.

Discovery was scheduled to launch at 1:36 a.m. ET from Cape Canaveral, Fla., on a 13-day flight to the International Space Station.

The space agency rescheduled the launch for 1:10 a.m. ET Wednesday.

Last month's Endeavour mission, carrying Canadian astronaut Julie Payette, was postponed several times because of bad weather at the launch site.

U.S. Comm. Rick Sturckow heads Discovery's crew of seven astronauts who will deliver almost 8,000 kilograms of equipment and supplies to the International Space Station during the mission.

Also scheduled to fly to the station are pilot Kevin Ford, mission specialists Patrick Forrester, Danny Olivas, Jose Hernandez and Nicolle Stott, all from the United States, and mission specialist Crister Fuglesang from Sweden.

The crew of the space shuttle Discovery, from left, mission specialist Nicole Stott, European Space Agency astronaut Christer Fuglesang of Sweden, mission specialists John Olivas, Jose Hernandez and Patrick Forrester, pilot Kevin Ford, and Comm. Rick Sturckow. (Reuters)Olivas will perform three spacewalks on the mission, one with Stott and two with Fuglesang.

Stott will also join Canadian Robert Thirsk and the other four members of the space station crew, replacing American Tim Kopra, who is scheduled to return to Earth with the rest of Discovery's crew.

Included in the equipment making the trip into orbit is a treadmill named for comedian Stephen Colbert.

Earlier in the year, Colbert encouraged viewers of his program The Colbert Report to vote in an online contest to name a future space station room after him. Colbert won the contest but NASA instead chose to name the piece of exercise equipment after him.

Treadmill will slim 'chubby' astronauts: Colbert

Its full name is Combined Operational Load Bearing External Resistance Treadmill and it will fly up in more than 100 pieces and won't be assembled until sometime next month.

Colbert could not attend the launch but said in a recorded message that he couldn't be prouder that his treadmill soon will be installed at the space station "to help finally slim down all those chubby astronauts.

"Let's face it, being weightless is mostly just a desperate bid to get away from that bathroom scale every morning," Colbert said.

"But you guys and gals are ambassadors to the universe. Don't make us look bad. Put down the astronaut ice cream, tubby. Tubby, tubby, two-by-four, couldn't fit through the air lock door."

With files from The Associated Press