Thursday, December 17, 2009

Seems We've Been Looking for Other Earths in Not Enough Places

Starting yesterday several websites were excited about the news that astronomers have discovered a so-called Super-Earth orbiting a red dwarf star a mere 40 light years from our own planet. The links include:
  • a press release yesterday on EurekAlert! from the Harvard-Smithsonian Center for Astrophysics;
  • an analysis on MSNBC's by Cosmic Log's Alan Boyle; and
  • a separate analysis by John D. Sutter on CNN.
All three refer to an article by the researchers in today's edition of the journal Nature; but there is no on-line link to the full coverage without purchasing it or subscribing to Nature.

Philosophically speaking, the critical point about the new discovery is that we have been too narrow in where we have looked for other planets like ours. When the focus was only on stars in the range of our sun's size and intensity, the results were paltry. But very shortly after researchers went unconventional and allowed themselves to look in the direction of dimmer stars, they started to find Super-Earths much faster. Imagining greater possibilities unveiled a more complex reality.

Apart from the full article, CNN is best at explaining the significance of the new find. Here are excerpts from its analysis:

While the planet probably has too thick of an atmosphere and is too hot to support life similar to that found on Earth, the discovery is being heralded as a major breakthrough in humanity's search for life on other planets.

"The big excitement is that we have found a watery world orbiting a very nearby and very small star," said David Charbonneau, a Harvard professor of astronomy and lead author of an article on the discovery, which appeared this week in the journal Nature.

The planet, named GJ 1214b, is 2.7 times as large as Earth and orbits a star much smaller and less luminous than our sun. That's significant, Charbonneau said, because for many years, astronomers assumed that planets only would be found orbiting stars that are similar in size to the sun.

Because of that assumption, researchers didn't spend much time looking for planets circling small stars, he said. The discovery of this "watery world" helps debunk the notion that Earth-like planets could form only in conditions similar to those in our solar system.

"Nature is just far more inventive in making planets than we were imagining," he said.

In a way, the newly discovered planet was sitting right in front of astronomers' faces, just waiting for them to look.

There were no technological reasons the discovery couldn't have happened long ago, Charbonneau said.

1 comment:

Gerald T Floyd said...

Footnote: A few hours after this posting, I came across an article from the San Francisco Chronicle, reprinted in the Houston Chronicle. It refers to an Australian-American team that has also found "at least six new planets orbiting nearby sun-like stars beyond the solar system, including two 'super-Earths.' It's at

Their work is detailed in an article in the Astrophysical Journal; but it also will not allow access to the full article without purchase or subscription.

Science Daily has a good summary of their findings at

The stars for these Super-Earths are more sunlike, and one is only 28 light years away. So it should not be concluded that the focus of all research should shift to dimmer stars.