It was hard for astronomers to argue with astronaut and astrophysicist John Grunsfeld when he announced that the Hubble Space Telescope would no longer be serviced again, meaning the venerable observatory's days, or at least its years, were numbered.

Now chief scientist at NASA, Grunsfeld  flew aboard the space shuttle Columbia's March 2002 mission to attach a new camera to Hubble, he took along an important science paper written by Edwin Hubble, for whom the telescope was named.

Edwin Hubble discovered in the 1920s that all galaxies are receding from each other -- that the universe is expanding.

Grunsfeld presented the decades-old paper to the American Astronomical Society (AAS) at a Seattle meeting in January 2003 and said, according to AAS president Catherine Pilachowski, that "he knew how dangerous the shuttle was but that the astronauts knew how important Hubble is to scientists and to everyone in the world."

Edwin Hubble's science paper, having flown to the telescope that bears his name, is now on the wall of the AAS headquarters in Washington, DC. The shuttle, it turned out, was dangerous, as seven of Grunsfeld's colleagues learned less than a month later when Columbia disintegrated upon re-entry.

On Friday, Grunsfeld confirmed what many astronomers feared, that Hubble would not be serviced again. The next time it fails, it is done. He cited astronaut safety as the primary reason for the decision.

"We all feel it as a devastating blow," Pilachowski said in a telephone interview from her home, just hours after NASA administrator Sean O'Keefe told a group of NASA employees about the decision.

Pilachowski represents more than 6,000 members, many of them working professional astronomers. "It was sort of sense of shock and disbelief on everyone's face," she said.

For anyone who thought only the public is wowed by Hubble's jaw-dropping images, Pilachowski said, "We astronomers see the pictures and they take our breath away. And we also see the incredible science." She said the decision was surely difficult for NASA officials, too.

The AAS president said initial frustration is likely to grow into appreciation for the decision, given the concern for human safety.

There is more to the decision, though. Under President George W. Bush's new space plan, the shuttle is to be devoted to finishing the construction of the International Space Station and then the fleet will be retired. That alone seemed to doom Hubble earlier in the week, when Bush announced his vision. Grunsfeld cited the Columbia Accident Investigation Board recommendation requiring a second shuttle be on the launch pad and ready to rescue astronauts doing a Hubble upgrade.

None of this can remove all the sting for astronomers losing the greatest astrophotography machine of all time. It is to be replaced in 2011 by a better observatory, the James Webb Space Telescope, but it's doubtful Hubble can last that long without being serviced.

"Hubble is a premier facility," Pilachowski said. "Hubble has a special place in everybody's heart."

Indeed, the observatory, launched in 1990, is often the only telescope that comes to the lips of the average person -- in a bar, a mall or a school -- asked to name a telescope.

Hubble has also done "really outstanding science," Pilachowski said and other astronomers agree. "To think of its premature end is just a hard thing to swallow."

Had it been serviced one more time, Hubble might have survived through 2011. Without servicing, it's unknown how long Hubble will last. It is in need of replacement gyroscopes to keep it properly pointed. And the servicing mission, tentatively planned until Friday, would have installed two new instruments to enhance Hubble's capabilities.

Astronomers are already contemplating creative ways to keep it online.

"It's not as if they're about to turn Hubble off," Pilachowski said. "We're hopeful that Hubble will continue to be productive for several more years." She added that researchers must now "think very hard about how do we get the most out of these last few years of Hubble."

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