Sunday, April 21, 2013

Quest for new worlds

It's never too early to start looking around for new worlds that might be colonized, one day, by our human descendants. Incidentally, it's becoming more and more likely that many of these descendants, in the not-too-far-distant future, will be quite different creatures to us, since their genomes will no doubt contain various synthetic genes inherited from top-class intelligent robots. There's no sound reason—other than old-fashioned nostalgia—for hanging around here longer than necessary on the charming planet Earth, with its depleted resources and damaged ecosystems. Adventurous human societies should be able to take advantage of their Earth-based history and experience in order to go about things in a better fashion at other spots in the universe.

We first have to find new worlds, and then our descendants will have to invent some way of reaching them. Theoretically, neither of these two challenges would appear to be insurmountable... though I don't have the least idea of what the solutions might look like. When our descendants get around to finding solutions to the above-mentioned challenges, they'll surely be amazed to think that we old-timers of the start of the 21st century were incapable of envisaging such answers.

Astronomers in search of new worlds evoke the celebrated children's story of Goldilocks and the three bears, by the English romantic poet Robert Southey [1774-1843].

The Goldilocks metaphor is a little like the Down Under joke at the end of one of my recent blog posts [display]. In the empty house of the three bears, in the middle of the woods, the little girl comes upon three bowls of porridge, apparently ready to be eaten. Feeling hungry, she tastes the porridge in Father Bear's big bowl, but it's too hot. Then she tries the porridge in Mother Bear's bowl, but it's too cold. Finally, in Baby Bear's little bowl, Goldilocks finds that the temperature of the porridge is "just right", so she gulps it all down. In the case of planets orbiting around a star, there is sometimes an orbital zone whose temperature, like that of the planet Earth, is apparently "just right" for human existence.

Last week, astronomers were thrilled to announce that NASA's Kepler spacecraft had discovered a pair of so-called exoplanets orbiting within the Goldilocks zone of a star that is henceforth named Kepler 62, located in the constellation Lyra, at a distance of 1,200 light-years from our solar system. Here's an artist's impression of a "sunrise" in the vicinity of one of these planets:

The chief of the Kepler project, William Borucki, claims that this pair of exoplanets is the most favorable site for life that has ever been detected by the Kepler spacecraft since its launch by NASA in March 2009. Click here to visit the Wikipedia page on this project.

Meanwhile, plans are already under way for NASA's next-generation spacecraft designed to look for new worlds. Called the Transiting Exoplanet Survey Satellite (TESS), and designed by teams at the Massachusetts Institute of Technology (MIT) headed by George Ricker, the new vessel will be launched in 2017. Here's an artist's impression of the TESS spacecraft:

The hundreds of small exoplanets discovered by Kepler have all been linked to stars whose great distance means that they're faint. TESS, on the other hand, will examine bright stars in a much larger area of the heavens. So, there's a good chance that this new spacecraft will be able to find new worlds for our descendants.

One might imagine a latter-day Columbus setting out towards obscure shorelines. The TESS adventure reminds me rather of future oak forests planted by conscientious landowners who know full well that neither they nor even their immediate offspring will ever sit in the shade of those great trees.

No comments:

Post a Comment