Dreaming of Galaxies. Here’s to James Webb.
This post originally appeared on the Newton blog on RealClearScience. You can read the original here.
The building 29 cleanroom at the Goddard Space Flight Center in Greenbelt, Maryland is a tinkerer’s dream. There, in an assortment of expensive pieces, rests NASA’s preeminent project of discovery: the James Webb Space Telescope.
Under development by NASA and Northrop Grumman engineers, the tennis court-sized telescope is currently slated for launch in 2018. When it takes its position in a solar orbit 930,000 miles from Earth — four times the distance to the moon — James Webb will grant a peerless gaze at the universe the likes of which we’ve never seen.
Just two years ago, the outlook for James Webb wasn’t nearly so optimistic. In July 2011, the United States House of Representatives’ appropriations committee on Commerce, Justice, and Science moved to cancel the project, contending that the project was “billions of dollars over budget and plagued by poor management.” For a time, it appeared that James Webb would go the unfortunate way of the Superconducting Super Collider: mothballed and left incomplete, a billion-dollar reminder of what could have been. But in November 2011, cooler heads prevailed. James Webb survived.
Space scientists across a spectrum of disciplines are now firmly looking forward to the future. Astronomers hope to use James Webb to identify the first stars that formed in the wake of the Big Bang, to examine the evolution of dark energy, as well as to study the physical and chemical properties of foreign planets and solar systems, potentially picking out the building blocks of life. Key to these aims is James Webb’s chosen method of stargazing: infrared imaging.
Infrared imaging focuses on wavelengths of light within the infrared spectrum — usually 700 nm to 1 mm. Those lengths are very short in absolute terms, but still far longer than visible light. A big benefit of focusing on infrared light is that it’s emitted by almost any source, provided said source is not cooled to absolute zero. It also has the ability to pass through astronomical gas and dust without being scattered, granting clearer images.
When light travels extremely far distances on the order of billions of light years, it shifts to the infrared spectrum. This means that James Webb, with its large, collecting array of mirrors, will be perfectly positioned to gather this light and peer farther into the galaxy, and thus back in time, than ever before.
As Stacy Palen, director of the Ott Planetarium at Weber State University recently stated onScience Friday, we may find more, much more, than we’ve bargained for.
“One of the great things about these discovery machines is that you think you know what it’s capabilities are, and you think you know what it’s gonna see. But when it comes right down to it, we’ve never looked at the Universe at this resolution in the infrared before, and we’ve never had this quality of data before, and we’ve never been able to look at this level of detail. And so I think the surprises are gonna be fabulous as we start to open a window that’s always been closed.
Back in 1990, James Webb’s remarkable predecessor, the Hubble Space Telescope, was launched into orbit a mere 374 miles from Earth. Since then, it’s far surpassed its original stated goals, delivering soaring, captivating images of the cosmos and functioning as perhaps the single most useful scientific instrument ever produced. Any astronomer in the world can submit a project proposal and request time on the telescope. Ideas and submissions constantly pour in, a torrent that has resulted in over 10,000 scientific papers based on Hubble data. This “science for the people” approach is slated to continue with James Webb. And of course, we’ll also be privy to even more dazzling photographs.
“The reason that the Hubble Space Telescope images were so staggeringly beautiful when we saw them was because the resolution of the telescope was so high, Palen told Science Friday. “And James Webb, because it’s a larger telescope, is going to give us even more detail”.
Nothing extraordinary comes without costs. James Webb, like Hubble, is slated to run well beyond original budgetary estimates, a fact which — as mentioned earlier — almost got the project canned. But this is expected. When building state-of-the-art machines to gaze far into the unknown, you often experience unforeseen snags. Attempting to do something that’s never been done before is rarely easy. Such actions can, however, deliver astounding results.
