This week saw the US House of Representatives Appropriations Committee put the James Webb Space Telescope on the chopping block. The Republican lead committee criticized the project for being over budget and “plagued” by poor management. An independent review had earlier suggested it was underfunded for a number of years. Who’s right?
There are no easy answers. So it’s probably worthwhile to examine some of the details about the capability of JWST versus the Hubble Space Telescope first. The key point I want to make is that JWST isn’t simply a big and better version of Hubble – it’s way more sophisticated and capable.
Starting with the most simple statistic first, JWST has a 6.5m diameter mirror, while Hubble is a mere 2.4m. But more criticially, JWST’s mirror is made of hexagonal segments that will be unfolded once it is launched (which is slightly scary when you think about it, but the engineers are adamant it will all work). Then there’s the length of the two telescopes, 13.2m compared to 22m: to put this in perspective the shield that protects JWST from the Sun’s glare is essentially the same length as a Bombardier Q400 aircraft!
But the key facts about JWST are really the science it can do. Not only will it be able to image 15 times the area that Hubble can, it is also optimized to see at mid to near infra-red wavelengths, beyond the limit of human seeing. This will allow it to see the very first galaxies to form in our Universe – something that Hubble can never do. It will help us unravel some of the mysteries of how stars and planets form, and even uncover pieces of the puzzle of how the elements and compounds necessary for life are distributed.
So if the JWST is so much better than Hubble, how come it’s on the chopping block? The need to repair Hubble’s flawed mirror lead to some of the most dangerous space-walks ever undertaken by astronauts. The total cost of the Hubble mission is now somewhere around $15B, and in that light, JWST looks peachy cheap at $6.5B.
In short, if you want to get some real concessions from the opposition then you put something big and juicy on the table. Knowing full well that the Senate Appropriations Commerce-Justice-Science sub-committee Chair (Barbara Mikulski) is a strong supporter of JWST since she comes from Maryland, home of the JWST Goddard Space Flight Center, the Republicans are loading their throwing arm with what is essentially the most expensive civillian scientific project in the US.
It would be nice to think this was just political brinkmanship (the JWST budget is but 1/2000th of the budget deficit!). But even before we consider the loss of the scientific discovery that would result, estimates suggest 2,000 high tech jobs are potentially on the line.
On top of these concerns, many astronomers recall the cancellation of the Superconduting Super Collider (SSC). At almost 90 km long it would have exceeded the capability of the LHC at CERN. The US could have maintained leadership in subatomic physics but the government chose not to. The reasons for cancellation were very similar to those we’re hearing about the JWST today: “cost overruns”, “poor management”, “need to cut spending”. If he US was prepared to give up leadership in the past, a repeat of history would be perversely unpoetic.
JWST is overbudget. Faced with what an external review essentially felt was underfunding, the managers of the project postponed non-critical work until it became critical. Budget safety margins weren’t as big as they should be. But the key fact is there are no significant technical barriers to launch. Despite all the perceived problems the mission has progressed. And let’s face it, how many space missions actually wind up flying on time? Anyone remember how many years late the original Space Shuttle was?
The next few days of negotiations between the various warring fraction of the US government will be interesting. It would be fun to be fly on the wall and listen to whether even a smidgeon of the science at stake is mentioned. Seems unlikely. So I’d like all the people involved just to take a look at the following movie about what actually motivates humans to do what they do. It isn’t chasing the mighty dollar, regardless of what economists might think.
Space is a plateau that science and technology has allowed us to reach. If we turn our backs on science and technology, and reaching out to discover the unknown, progress will become a luxury of the past.