Astronomers Look for Earth-Like Worlds
To learn more about the solar system’s formation and the potential for extraterrestrial life, speakers in an AAAS Annual Meeting press briefing said debating what makes a planet is not as important as finding bodies that have planet-like characteristics.At the 17 February 2008 briefing, Michael Meyer, an associate professor and astronomer at the University of Arizona, cited a paper he authored in the 1 February issue of The Astrophysics Journal in which he estimates between 20 and 60 percent of stars contain rocky planets similar to Earth around them.
These rocky planets, he said, might contain the necessary conditions to support life.
“I do not know exactly what a planet is, nor am I interested in a precise definition,” Meyer said. “I am much more interested in finding the characteristics of bodies in space.”
Deborah Fischer, a researcher at San Francisco State University, said extraterrestrial life is most likely to be found on planets of a certain mass and distance from a star. When a planet meets the two characteristics, Fischer said, it is possible the planet could support carbon-based life because the climate “will not be too hot or cold and water could pool.”
Alan Stern, associate administrator for space exploration at NASA, said that searching space to find new planets and life is like “looking for a needle in a haystack.”
“It’s like we want to explore all of North America, and we are on the Eastern Seaboard and we only know about the first 100 kilometers,” Stern said. “We really don’t know what we will find.”
The panelists -- who presented new findings from the Hubble, Spitzer and other telescopes and discussed what could be achieved with the next generation of optical telescopes-- agreed that more research is needed and called for increased funding to explore space.
“With more research, we will get more data that can create more effective exploration programs,” Meyer said.

