BALTIMORE - The astronauts who will service the Hubble Space Telescope were greeted enthusiastically Wednesday by astronomers who had faced the loss of the orbiting observatory when NASA canceled their mission.

The seven astronauts will be "doing as much as we can cram in" to the September 2008 servicing mission that will keep the Hubble alive, mission commander Scott Altman told a crowded auditorium at the Space Telescope Science Institute, which coordinates the use of the telescope.

"We will do our absolute best to leave the telescope in the most phenomenal condition that it can be when we let go of it with the robotic arm and set it loose on its next voyage," Altman said.

NASA scrubbed a servicing mission following the loss of the shuttle Columbia because of safety concerns. However, the mission was rescheduled in October following an outcry from scientists and the public.

Three of the astronauts on the mission have been on previous Hubble servicing missions, including John Grunsfeld, a self-described "Hubble Hugger."

"Thank all of you for hanging in there," Grunsfeld said, noting he was the recipient of the news when NASA scrubbed the servicing mission.

Grunsfeld said supporters were able to get some common sense back into the process "so we are able to train to make the telescope better even than it is now."

The institute staff were also shown videos of the seven training in a giant pool at the Johnson Space Center in Houston. Mission specialist Michael Goodwin, one of the astronauts who will perform the repairs in space, said staying rested and focused during the five consecutive days of spacewalks will be the toughest challenge for him.

Goodwin, Megan McArthur, Andrew Feustel and Mike Good are all rookies. Altman and Grunsfeld will be joined fellow Hubble servicing veteran Michael Massimo.

Without the repair mission, Hubble's batteries and stabilizing gyroscopes could die by the end of the decade, leaving the telescope useless. The $900 million mission should allow the Hubble to keep working until 2013, when the Hubble's successor, the James Webb (news, bio, voting record) telescope, is scheduled to be launched. NASA planned to display of a full-size model of the Webb Thursday on the National Mall in Washington.

The seven also took questions from the children of staffers who came to see the astronauts.

One asked what astronauts do if they have to go to the bathroom while walking in space.

"Just hold it," Feustel joked, adding that the air in the spacesuit is usually so dry he usually drinks all his water and doesn't feel the need during the six hours or so he is in the suit.

When asked what he does when he has an itch, Massimo said astronauts "do a lot of scratching before you get in the suit."