As one space observatory – ROSAT – came crashing back to Earth today, astronomers continued their fight to ensure that a powerful successor gets launched at all. Politicians have already tried to kill off the James Webb Space Telescope, despite its promise to build on Hubble’s work and make significant new discoveries about the universe.
A US Congress committee recommended axing the telescope earlier this year in cuts to NASA’s budget, even though three quarters of its parts have already been built. NASA has said the JWST remains a priority but the telescope’s supporters are keeping up the pressure on Congress to ensure the telescope flies.
Skymania News’s Paul Sutherland spoke to one of the JWST project’s six interdisciplinary scientists, Dr Heidi Hammel, executive vice-president of the Association of Universities for Research in Astronomy, about why this observatory is so important to the study of the cosmos.
Heidi told us: “The JWST is an innovative, different kind of telescope that is going to be able to do science that is simply not doable in any other way. It will be an infrared-optimised telescope and working at wavelengths of light that are not accessible to our ground-based telescopes. There are windows in the infrared we can work with but we won’t be able to have the sensitivity and stability that we’ll have with a space telescope like the JWST.
“For example, to really probe to the very earliest galaxies that ever existed. We’re getting hints of what they look like with the Hubble Ultra Deep Field but we can’t push far enough with Hubble. It doesn’t have the required sensitivity in the infrared, and we need to look in the infrared because that’s where the light has been shifted to by red shift. So we’ve got to push as far as we can in that direction to do that.
“There are so many different kinds of science. I could spend an hour talking to you about any one of them. For example, what I want to do in my own research is to study the ice giants of the solar system.”
Heidi added: “The JWST is going to be a great observatory in the true sense. It’s going to be pushing the boundaries of what we’ve been able to do. It’s just so far beyond the capabilities of what we have now that it is going to be revolutionising what we know. Hubble certainly did that and this is going to be taking astronomy to the next level.
“People ask me sometimes, what do we need this telescope for? And I tell them, look, I have pretty bad eyesight. When I go outside I can see there are trees out there because I see these big green things. But I remember walking out with a new pair of glasses and going, ‘Wow! There are actually leaves on those trees’. And that’s what Hubble did for us. It allowed us to see the leaves on the trees. But what JWST is going to do now is going to be like putting binoculars in front of your glasses. You’ll be able to see not just the leaves but the structure within the leaves, in the veins and the pores. It takes you that much further.”
The battle to save the JWST reminds Heidi of the fight that astronomers had with politicians to get Hubble launched. She said: “When I look at what is happening now with the JWST, it is just like the issues that were faced when building Hubble. You just change the names and change the years. All the same kind of issues were going on, which is a little disconcerting. One would have thought that people might have learned their lessons. But I think that any time you are trying to build something that no one has ever built before, you are going to be confronting these same kind of issues that Webb is confronting now.”
Heidi believes that the latest figure for the cost of the JWST, $8.7 billion, is realistic but warns that it could climb if the launch currently scheduled for 2018 is delayed again.
She said: “If it is delayed further, it will almost certainly cost even more. That is just the nature of these missions. There are a lot of people involved in crafting this mission. There’s more than 1,000 people working on building the components and starting to develop the testing procedures, to put it together both here in the United States and also there in Europe, and in Canada. There’s a lot of people involved. And if you extend the mission outwards, you have to keep these people working through that period. It doesn’t get cheaper if you make it take longer.
“Something that people can’t seem to get their heads around is that they’ve already spent $3.5 billion dollars on this telescope. That money has gone to pay for people and to pay for technology development and inventing these new technologies. That money has been spent already. And also it is not as if you need to have $8.7 billion today. The programme already had in the spending profile this $5 billion that was already there.
“So it’s not that it’s $8 billion more than it was, it’s a few billion dollars more than it was. People think this is is a big number, but big compared to what? It’s big compared to my salary, that’s for sure, but big compared to NASA’s budget? Well, not really. We’re basically talking about one 30th of NASA’s budget to build this amazing flagship mission that, just like Hubble has been iconic for NASA, but it’s a tiny, tiny fraction of what NASA does. And how big is that compared to the US budget? Well all of NASA is only half of one percent of the US budget. So we’re talking about one thirtieth of half of one percent of the US budget! In that context it really is not a big number, especially when you think about what you’re going to get for that. You’re going to get something that has never been done before.
“As you said yourself earlier, Paul, try to imagine astrophysics without Hubble. Twenty years from now it will be the same thing. Try to imagine how we could have progressed. We will progress. if they cancel JWST, we’re not all going to pack up our suitcases and go home. We’ll still limp along, we’ll still do astronomy, but we’ll be missing a key component to make the next big steps in astronomy.”
Heidi’s support for the JWST is driven by her own experiences working with its predecessor.
She said: “I joined the JWST project to pay back for Hubble. I had the most amazing experience when Comet Shoemaker-Levy 9 was crashing into Jupiter. I was a young astronomer and it was my first programme with Hubble and I got to watch this amazing event. The data we were getting from Hubble was just so incredible and I had nothing to do with building Hubble. I was just a young astronomer fresh out of a post doc and here I was using this amazing tool.
“I want to help make this amazing tool for the next generation of young astronomers. So when they come along, fresh out of a post doc, who knows what may happen. Maybe it will be a supernova going off in the Large Magellanic Cloud. I want them to have a facility like I had. That drive to make sure that the next generation of young people have even better opportunities, that’s what gets me through those moments of frustration.
‘When I look at the history books, I see that there were people who went through that frustration to make Hubble a reality and they got to the other side, so we’ll get to the other side with the James Webb Space Telescope too.”