Art Molella, Jerome and Dorothy Lemelson Director
|Hubble Space Telescope photo of the spiral galaxy NGC 3021. This was one of several hosts of recent Type Ia supernovae observed by astronomers to refine the measure of the universe's expansion rate, called the Hubble constant. Courtesy of NASA, ESA, and A. Riess (STScI)|
Next month, the Lemelson Center's annual symposium, held this year in collaboration with the Smithsonian's National Air and Space Museum, will celebrate fifty years of human spaceflight. One thing we will certainly be hearing about is just how hard it is to lift these bulky vehicles off the planet and keep them up there. In the face of such limitations, you have to ask, will humans--as opposed to robot devices--ever make it beyond Earth and the Moon in any meaningful way? How realistic is the possibility of visiting the solar system and beyond firsthand, perhaps even positioning ourselves to colonize other planets?
The cancellation of the Space Shuttle Program without a clear plan for what will follow it does not inspire confidence. Having once bounded to the Moon, humans seem to have fallen back to Earth and reverted into stodgy stay-at-homes. In the offing are some promising private initiatives, which our symposium will address. And yet, even were we to gather the courage and political will to venture forth again, can we ever hope to conquer the unimaginably vast times and distances involved? Despite intriguing speculation about wormholes and other futuristic "back doors" through the space-time continuum, current and foreseeable human space exploration must operate in an old-fashioned, mechanistic, Newtonian frame. While technology so often dazzles these days, when it comes to putting flesh-and-blood humans into space for the long term, it can still feel frustratingly sluggish, even clunky.
There are other ways to explore deep space, however. NASA's unmanned missions into the solar system and beyond have been absolutely spectacular. Who can forget the exploits of the unstoppable Mars Rover--the next best thing to being there? The controversy is ongoing and spirited about whether crewed or unmanned missions are better. But on the grandest scale of cosmic understanding, I was particularly excited by the announcement earlier this month about the research that won the 2011 Nobel Prize in physics. Here was another, even "lighter" way to travel, with technology in the form of improved instrumentation conjuring some of its old magic.
|Adam Riess. Photo by W. Kirk, Johns Hopkins University, and STScI|
Using ultra-sophisticated space- and ground-based telescopes as well as more powerful computers and digital sensors, Saul Perlmutter, Brian Schmidt, and Adam Riess, members of two competing research teams, shared the Prize for discovering the "accelerating expansion of the universe through observations of distant supernovae." Journeying on light waves as far back into space and time as human beings ever have, both teams ended up with the same result: they found that light from particular types of exploding stars (type Ia supernovae, to be exact) was much weaker than expected. To astrophysicists, these incredibly precise, unexpected measurements had a stunning implication: the expansion of the universe, dating from the Big Bang, is speeding up at an ever-increasing rate, rather than slowing down as prevailing models had us believe. If this keeps up, states the Nobel awards committee, citing poet Robert Frost, the universe is destined to end "in ice," with things flying endlessly and hopelessly apart.
|Brian Schmidt. Photo by Tim Wetherell, courtesy Wikimedia Commons|
Why this is occurring remains a deep mystery; dark energy, that unknown force that seems to make up most of the universe, is an oft-cited culprit. Whatever the cause, the discovery has completely upended cosmology. In fact, taken by surprise, the prizewinning researchers at first couldn't believe their eyes. As Perlmutter, who won half the Prize, recalled: "[My] team made the discovery in steps, analyzing the data and assuming it was wrong. And after months, you finally believe it.… It's not quite a surprise anymore. I tell people it's the longest 'ah-ha' experience that you've ever had." (To hear more about the implications of the discovery and the firsthand testimony of the prizewinners, see this Guardian blog.)
So even as we fixate on space shuttles, space stations, and other human space missions, it is inspiring to see how breakthroughs in scientific instrumentation are fomenting a quiet revolution on another, grander frontier. While I suppose it's not the best news that our universe is disintegrating into cold nothingness, this year's Nobel physics prizewinners show how amazingly nimble we can be if we just offload the weight that binds us to Earth. Astrophysicists and cosmologists are indebted, of course, to the spacewalkers who maintained and made crucial repairs to the Hubble Space Telescope. Through the Hubble, and decades of other space probes, as well as ground-based telescopes, earthbound discoverers have been able to traverse eons of time and parsecs of space (equivalent to about 19 trillion miles) to the very edges of the visible universe, and to make a shocking discovery there. Travel by light and sight, not by the body, is proving to be the ticket for a quick lift into deep space.
From Prototype, October 2011