Bob O’Dell has been with the Hubble Space Telescope since before its launch, some 20 years ago

by Laura M. Miller
photo by John Russell

For Vanderbilt’s current undergraduates, there has always been a Hubble Space Telescope. Even for the rest of us, imagining a world before the existence of Hubble’s richly intense images – such as the pillars of the Eagle Nebula or the dense radiance of the galaxies in the Hubble Deep Field – is difficult. These breathtaking images have become a mainstay of our workaday world, emailed back and forth vigorously as reminders that the universe is infinitely bigger than our workstations.

Their astonishing beauty can easily be taken for granted, as can many of the Hubble’s manifold discoveries, which have become such a part of the popular consciousness that we might forget that before April 24, 1990, they were not confirmed: dark matter; dark energy; that the universe’s expansion is occurring at an accelerating rate; that most galactic hubs have a supermassive black hole in the center; that gamma-ray bursts come from the collapse of stars; that leaving a camera trained for 10 days at one area of space will give you an image of a “deep field” of galaxies and the closest view ever to the beginning of the universe; that solar systems are formed from discs of gas and dust around stars; and what happens when two solar system bodies collide.

Bob O’Dell, Distinguished Research Professor in the Department of Physics and Astronomy, has been with the Hubble since its inception, well before its launch into space 20 years ago. O’Dell was part of the team that conceived and designed the Hubble, and he was a primary advocate for gaining funding for it. He even, for all practical purposes, named it – after Edwin Hubble, the astronomer who was one of the parents of the idea of an expanding universe.

In 1971, NASA began a feasibility study for a space-based telescope, calling in a group of senior astronomers and engineers that included O’Dell, who left the safety of his tenured position at the University of Chicago to become a project scientist at the Marshall Space Flight Center in Huntsville, Ala., where the Hubble was being developed. By 1972, the team had a preliminary design for the Hubble. Since many on the team were committed to multiple projects, and O’Dell had committed fully to the space telescope project, he was called upon to beat the bushes for funding and support of what would become the Hubble Space Telescope.

Space astronomy had been in place prior to the advent of the Hubble. Since 1960, NASA had been doing observation from the Orbiting Astronomical Observatory series of spacecraft for a few minutes at a time, with limited success.

“There was some good science,” O’Dell said, “but not a whole lot. It was just as expensive as the Hubble overall, but it was not inspiring confidence.”

Since he was technically a civil servant, O’Dell could not lobby, so his job was to find key people – heavy hitters in the community and from major institutions such as Harvard, Chicago and Cal Tech – and convince them to fund the space telescope’s preliminary design. The team also enlisted international investors such as the European Space Agency.

“It doesn’t save a lot of money, as interaction is more expensive, but managers know it is much harder to cancel a project when you have international partners,” O’Dell said.

One of O’Dell’s strengths as a fundraiser was that he was an outsider to NASA.

“I had no sense of institutional loyalty,” he grinned. “I was a space wrangler. I took some liberties. I did as much as I could legally do.”

O’Dell’s greatest challenge was convincing Congress to invest money in a space-based telescope vs. more ground-based research.

“For $300 million, you could get 20 duplicates of Palomar,” O’Dell said, “or build an even bigger mirror for a ground telescope.”

The Hubble team went to battle with the familiar.

“We had to do it. The step from a ground-based telescope to a space-based telescope is the biggest single step we could have taken in astronomy. It is comparable to the step from the eye to the first telescope.”

Through time and persuasion, the team won funding and assembly was able to begin, albeit without a well-defined budget.

“When building something the first time you have no idea how it is going to turn out,” O’Dell said.

The project took a lot longer and cost a lot more than the team – which by now had undergone several changes of cast – expected when the project started. But by 1978, construction on the Hubble had begun.

Another element affecting the timing of the Hubble’s launch into space was the development of the space shuttle. The technologies were developing side-by-side, with the Hubble counting on the shuttle for its launch and also for regular maintenance.

There is an elegant, almost symbiotic quality to the design of the telescope and the design of the shuttle. The Hubble is designed according to the capabilities of human astronauts to do repairs, and the cylindrical shape of the telescope – dependent on the shuttle for its deployment – perfectly reflects in diameter and length the inside of the shuttle’s hold, once the telescope’s wings are folded up.

Although the Hubble was ready to launch in 1982, the telescope had to wait until the shuttle program had room on its schedule to fix the instrument in space. The telescope was finally readied for launch in late 1986, but the Challenger disaster in January delayed the launch for four more years.

Once the Hubble was in place, it got public attention for the fact that one of its lenses needed adjustment; the public had little sense of the discoveries to come. Once the lens was fixed, the proof of O’Dell’s argument came pouring in, creating a grand resource of data and also introducing an entirely new way of “doing astronomy.”

The Hubble Space Telescope fundamentally changed how astronomy is done – not only physically, but the ideology of the research itself. Astronomers who came of age before the Hubble was launched in 1990 can differentiate the astronomy world into pre- and post-Hubble.

To begin with, Hubble is the first space-borne observatory, which means that views of the universe are available 24 hours a day, not just when the sky is dark. Professor of Astronomy David Weintraub noted that when he joined Vanderbilt’s faculty in 1991, “Astronomers’ hours were a running joke – the idea that you would be active doing your work from 11 at night to 4 in the morning. But now you can work anytime.”

It also changed where work could be done.

“When I arrived at Vanderbilt, I would spend about a week of each month on the road, going from one telescope to another depending on what I was working on,” Weintraub said. “A lot of astronomers still do travel to telescopes on the surface of the Earth, but for many of us, that is no longer the issue. Now I can do almost all my work in space.”

Hubble not only changed when and where astronomy could be done, but perhaps most importantly, how it is done.

“The prior model,” Weintraub said, “was that you went to a telescope and whatever images you collected on photographic tape or plates were yours. No one else had access to it forever.” This meant that if something happened to the individual astronomer, his or her work might be completely lost to another astronomer who might have been able to use it.

The public-domain research model was actually a selling point for the telescope, part of the persuasion O’Dell put together to gain funding.

“Hubble changed the rules, and a lot of that was due to Bob’s influence when he was arguing for it before Congress,” Weintraub said. “You and I own the Hubble as American citizens. We paid for it. So by Congressional fiat that data belongs to you and you should have access to it. In principle, all of those images are owned by the public.”

A scientist who proposes a project to the Hubble has a 12-month exclusivity option in which the data that the telescope collects will only be available to him or her. After a year, the data becomes part of the Hubble’s online archive, which is public domain.

Even the newer generations of astronomers who were born into the world of Hubble have an almost visceral recognition of the telescope’s importance.

“For scientists of my generation who have come of age as astronomers in the past 20 years,” said Keivan Stassun, associate professor of physics and astronomy, “the Hubble and the scientists who have built its legacy serve as a source of inspiration for the kinds of ‘grand science’ it is possible to achieve.”

Stassun’s own Ph.D. dissertation, a study of stellar birth in the Orion Nebula, included O’Dell’s now-famous Hubble photos of the nebula, published as Stassun was beginning his Ph.D. studies.

The Hubble archive is a vast trove of resources and may be its greatest legacy. To date, the telescope has looked at more than 30,000 celestial targets, collecting more than half a million photographs. Long after the Hubble has ceased operation, that data will be available to the public. And all data in each photograph – not just the object photographed, but also the phenomena in the background which may be of interest to another astronomer someday.

All things end, and the Hubble’s eventual demise is built into its elegant design. Just as the Hubble depended on the shuttle for its launch, it depends on the shuttle for maintenance. The end of the shuttle program also marks the beginning of the end for the Hubble, which, although fitted with redundant systems and technology that has been improved and replaced over the years, will eventually go dark with no one to service it.

Gradually, Hubble’s machinery will fail. A recent extension by NASA of its operations contract has assured its life until the end of April 2013, after which point its capacities will become more and more limited as different systems give out over the years, “restricting,” in O’Dell’s words, “the kind of science you can do.” Even the more durable, improved components will run out, and eventually support for operating staff on the ground will be invested elsewhere as the telescope loses its powers.

Hubble’s work will be continued by the James Webb Space Telescope, set to launch in 2014. The Webb will be bigger, better able to see red-shifted galaxies, and will see at a longer wavelength, so although the imagery will not be as crisp, it will be “better at looking at the earliest universe,” O’Dell said. Also, the Webb’s infrared capabilities will allow it to see through clouds that block visual light, so it will be better at observing star formation. The same organization operates both telescopes, according to O’Dell, so they will run the archive for the Hubble at the same time a new archive is created for the Webb, allowing for continuity.

But do not mourn the Hubble prematurely. It is made up of many individual pieces, and it is difficult to predict exactly when each one will cease to function.

“If you drive a car,” O’Dell said, “can you know exactly when the water pump is going to give out? A knowledgeable person can estimate, but it might last much longer.” We will be studying – or simply staring in awe – at new Hubble images for years to come.

To see images captured by the Hubble Space Telescope, visit www.spacetelescope.org.

Posted 08/01/10