Image: NASA, ESA, P. Kalas, J. Graham, E. Chiang, E. Kite
(University of California, Berkeley), M. Clampin (NASA Goddard
Space Flight Center), M. Fitzgerald (Lawrence Livermore National
Laboratory), and K. Stapelfeldt and J. Krist (NASA Jet Propulsion
Laboratory)

Exoplanets are planets in other solar systems. Though astronomers have detected over 300 exoplanets since 1995, we only have visible-light images of one of them. These photos of the planet Fomalhaut b, taken by the Hubble Space Telescope, have just been published in Science magazine by UC Berkeley astronomer Paul Kalas. The exoplanet Fomalhaut b orbits the star Fomalhaut (pronounced "foam-a-lot"), and at 25 light years away is the closest exoplanet that we know of.

Up until now, astronomers could only detect exoplanets using indirect methods. To learn more about the star wobbles and dips in starlight that indicate other planets are out there, check out QUEST's radio story, Exoplanets, and QUEST's television story, Planet Hunters. These exoplanets are trillions of miles away, but the research happens close to home at the Lick Observatory near San Jose, and at the Chabot Space and Science Center in Oakland.

Over the next few years, astronomers will likely detect additional exoplanets, and will learn much more about them. In 2009, NASA will launch the satellite telescope Kepler, which will be able to detect smallish Earth-sized planets. And in 2013, the James Webb Space Telescope will go into orbit. As stated in this press release, astronomer Paul Kalas hopes the James Webb Space Telescope will tell us whether there are other planets orbiting Fomalhaut – and whether those planets might be able to sustain life. Who knows – maybe on one of those planets, aliens are collecting snapshots of Earth.

Artistic rendition of exoplanet Gilese 436 b, created in Celestia

Once astronomers have found an extrasolar planet, also called an exoplanet, they look to see if it is in the Goldilocks zone. This is an area of space in which a planet is just the right distance from its' parent star so that the surface is neither too hot nor too cold. A habitable temperature means that the planet could possibly host liquid water, an ingredient for life.

A number of exoplanet findings have come from astronomy teams in Switzerland and near San Jose at Lick Observatory. Astronomers at Lick made news in the fall of 2007 when they discovered 55 Cancri. The discovery of the five-planet system came after nearly 20 years of observations. Also in 2007, astronomers with the Geneva Extrasolar Planet Search Program discovered the most earth-like planet ever found. Gilese 581 c lies in the Goldilocks Zone, it's surface temperature ranges from an estimated 32 degrees Fahrenheit to 102 degrees Fahrenheit. The research team that discovered the new planet believes it may have a developed atmosphere and be covered with oceans.

Curious to see how astronomers hunt for extrasolar planets, I took the trip up the long, windy road to the top of Mt. Hamilton. It is a beautiful drive up to the observatory and it's wise to take your time so that you can enjoy the ideal California landscape of rolling hills dotted with oak trees and wildflowers. The 365 sharp curves along the 19 mile road will also slow you down.

At the top of Mt. Hamilton are several white domes dotting the 4,200-foot crestline. From Lick Observatory you can see forever– not just across the vast northern California landscape but out into our own galaxy and beyond. By coincidence, the night I was there astronomer Debra Fischer confirmed five new planets outside our solar system. The discovery was the culmination of five years of watching these specific planets from Lick's 3-meter Shane Telescope. Fischer and her colleague Geoff Marcy will publish their findings soon. These two astronomers are obsessed with looking for exoplanets, they just returned from the Andes mountains in Chile, where they spent day and night for several weeks hunting for planets. But Fischer and Marcy are not the only ones who have caught the exoplanet bug.

Scientists at NASA are nearly ready to launch a bus-sized telescope into space. NASA's Kepler Telescope which will orbit our sun, will be trained on a hundred thousand stars at a time. It may be our best chance yet for finding new life in outer space. The telescope is scheduled to launch in February. Kepler will find planets by looking for tiny dips in the brightness of a star caused by planetary transits.

Make sure to check out our photo set on Flickr which includes: photos of Lick Observatory; the Kepler testbed at NASA Ames in Mountain View; the Kepler spacecraft assembly in Boulder, Colorado; and artists' renditions of exoplanets discussed in this report.You can also hear our radio story on the search for exoplanets, watch the Planet Hunters TV story online and find additional links and resources.