Source: The Houston Chronicle
Two decades ago today space shuttle Discovery launched from Florida’s Kennedy Space Center, carrying the Hubble Space Telescope in its payload bay. Among the mission’s five NASA astronauts was Steven Hawley, an astronomer now at the University of Kansas.
Below is a transcript of an interview I did with him Friday.
| . |
How technically challenging was the Hubble deployment mission?
I would say there were definitely some specialized aspects. The altitude was critical. Operationally it was higher than we typically flew the shuttle, and for Hubble I remember having lots of discussions about the minimum altitude we needed to get to before we were allowed to release it. The plan had been, over Hubble’s lifetime we would have servicing missions every three years or so. If you deployed it at a lower level than you planned to, orbital drag would cause it to have a lower orbit more quickly. That would have required more frequent servicing missions and you’d never get out of that loop. At some point you’d have to service it so often that it may not make sense to even release it. So there were a lot of important issues associated with the altitude.
As this was being deployed, did you think it was going to revolutionize astronomy, or were you thinking this was just another instrument?
I was definitely thinking this was going to be the most amazing thing astronomy has ever seen. I really felt that. I also was thinking about all of the people who had spent significant portions of their career working on Hubble so that we could launch it. Those were the two things I was thinking about.
In other words, with all those careers on the line, you wanted to be sure you didn’t mess it up?
Absolutely. For all the people who had worked on it, and for all of the promise it held. We were very conscious about not screwing it up.
|
|
Were you aware of the problem with the mirror on orbit, or did that crop up later?
It came up later. It was probably a month or so later when they were doing the start-up tests and trying to refine the focus that they found an aberration with the mirror.
What did you think when you heard about that?
It was very disappointing. That may be an understatement. Because again, of the promise the telescope had, if its performance was compromised it’s not clear what results it would have actually had. In hindsight, had we never fixed it, the telescope would have been a tremendous instrument all the same because it still had tremendous sensitivity and it still had tremendous resolution. The problem with the bad mirror is that you couldn’t achieve both with precision simultaneously. However I suspect that nobody would have paid attention to this.
Now, 20 years on, the telescope is stronger and working better than ever. Does that surprise you?
I guess I would say, honestly no, but in part yes. The plan all along was to be able to service it with maintenance and bringing up state-of-the-art technology. We always envisioned putting new instruments into it that would be state-of-the-art. Now I probably didn’t imagine how remarkable these new instruments would be. The ability of the new instruments is more than I anticipated, so we probably have achieved more with the telescope than I would have thought.
In your list of spaceflight accomplishments, where does being part of the Hubble deployment rank?
It’s right up there. I was lucky enough to get to go back in 1997, so I got to be part of two Hubble missions. There’s a couple reasons why this is really special. Professionally, the fact that I got involved with Hubble, as an astronomer I’ve gotten to see it revolutionize our understanding of the universe and now I get to talk to my students about it. All of that is great. The other thing is that, for the people who think the shuttle goes to the moon and launches from Houston, they’ve heard of Hubble, so it’s neat to have been involved in something that has such popular appeal. They have pictures in classrooms and everybody’s heard of the Hubble Space Telescope. To think that we had a little role in making that possible is very rewarding.
