Thursday, August 25, 2016

NOVA: “Invisible Universe Revealed” (PBS, 2015)

by Mark Gabrish Conlan • Copyright © 2016 by Mark Gabrish Conlan • All rights reserved

Last night I watched a NOVA episode called “Invisible Universe Revealed” that told the entire history of the Hubble space telescope, from its origins as a NASA proposal in the 1960’s — it was advanced by a woman astronomer named Nancy Roman, who got a job with NASA after she couldn’t get a tenure-track teaching job because it was 1959 and she was a woman (it’s amazing that that kind of shit was still going on in my lifetime!) — and targeted by Senator William Proxmire (D-Wisconsin, who was first elected in 1957 to fill Joseph McCarthy’s seat after McCarthy died) as one of the wasteful government projects he thought should be canceled. The appropriation nonetheless went through in 1977 and the Hubble duly got launched in 1990 — and promptly became a national laughingstock because its elaborate array of cameras and mirrors produced only blurry images that were scientifically useless. It turned out one of the mirrors had been ground about two micrometers too flat, and a crew of astronauts from the space shuttle had to install an array of new mirrors that looked like a shower head (and they were designed by a man who actually got the idea for the corrective mirror from a shower head!). Hubble has been serviced in space five times in all, though after the last mission in 2009 the space shuttle was decommissioned so it will eventually fall to earth and vaporize like any other satellite (though there’s a plan by NASA to brake it in space so at least the mirrors can be salvaged).

The most interesting aspect of the Hubble was that it actually did advance our knowledge of the universe, not only that it’s expanding but the rate of its expansion is actually increasing (earlier astronomers had thought it would slow down due to the force of gravity), and that every galaxy contains a black hole at its core that basically provides the gravitational “glue” that holds it together. The Hubble (named for Edwin Hubble, the 1920’s astronomer who first realized that there were other galaxies in space — before that all scientists, including Albert Einstein, had simply assumed our Milky Way galaxy was the only one) also discovered the mysterious and still not understood force called “dark energy.” The Hubble’s images are absolutely fascinating aesthetically and also have proven scientifically important — they’ve given us our first views of the formation of stars, and incidentally confirmed the modern theories of star formation that hold (among other things) that all stars have solar systems — planets are an inevitable result of the way stars are formed — which means that if every star has planets, the odds that there is life elsewhere in the universe are vastly increased. The PBS show on the Hubble was first aired in April 2015 and is a good deal better than the rather tacky DVD on the Hubble I’d seen earlier, 15 Years of Discovery (it’s been 26 years of discovery so far and, even though the demise of the shuttle program means it can no longer be serviced in space, it’s still up there, still taking stunning pictures of star formations, planetary nebulae — which are the detritus of dying stars — and the Cepheid variable stars and supernovas that proved the existence of other galaxies and the expansion of the universe in the first place).