Exoplanets

Understanding The Drake Equation: An Interview with Frank Drake Conducted by Andrew Fraknoi (June 24, 2012)

With SETI celebrating their 30th anniversary, an interview with Frank Drake from 2012 has been released. For those not familiar with Drake, he was the first president of SETI, and creator of the “Drake Equation” which adresses the probability of life (simple or advanced) in star systems other than our own.

The interview was conducted by Dr. Andrew Fraknoi (Foothill College / Astronomical Society of the Pacific), and covers Drake’s career, his current thoughts on the search for life elsewhere, and his recent thoughts on his now-famous equation. Additionally, Drake reflects on the explosion of exoplanet detections as of late (no confirmed exoplanets had been detected when Drake originally derived his equations).

Learn more about SETI at: http://www.seti.org/

Investigating Exoplanet Surfaces

Artist's concept of the first rocky world discovered by NASA's Kepler mission. The planet, called Kepler 10-b, is shown in front of its host star. Image Credit: NASA

Artist’s concept of Kepler 10-b, the first rocky world discovered by NASA’s Kepler mission. Image Credit: NASA

Numerous rocky, Earth-like worlds have been discovered by transit surveys such as the Kepler mission. For those familiar with the transit of Venus last year, exoplanet transits are the same idea – an exoplanet crosses the face of its parent star as perceived by observers on Earth. By comparing the amount of starlight the transiting planet blocks and the total starlight emitted by the host star, astronomers can determine the radius of a transiting planet.

Recent surveys have hinted at the existence of exoplanets with rocky surfaces, making them similar to our own “terrestrial” planets Mercury, Venus, Earth and Mars. However, a number of the exoplanets thought to have rocky surfaces appear to not have any significant atmospheres. One such exoplanet is Corot-7b, which orbits very close to its parent star. Exoplanet 55 Cancri e, estimated to have roughly twice Earth’s radius and roughly eight times Earth’s mass, also may be a rocky planet, and perhaps even made of diamond.

Read my full article on how researchers hope to better understand the surfaces of distant planets at: http://www.astrobio.net/exclusive/5493/investigating-exoplanet-surfaces

Earth Sized Planets “Next Door”?

Astronomers estimate that six percent of red dwarfs have a temperate Earth-size planet, as close as 13 light-years away. Image credit: D. Aguilar/Harvard-Smithsonian Center for Astrophysics

Astronomers estimate that six percent of red dwarfs have a temperate Earth-size planet, as close as 13 light-years away. Image credit: D. Aguilar/Harvard-Smithsonian Center for Astrophysics

Using publicly available data from NASA’s Kepler space telescope, astronomers at the Harvard-Smithsonian Center for Astrophysics estimate that six percent of red dwarf stars in the galaxy have Earth-size planets in the “habitable zone,” the range of distances from a star where the surface temperature of an orbiting planet might be suitable for liquid water.

The majority of the sun’s closest stellar neighbors are red dwarfs. Researchers now believe that an Earth-size planet with a moderate temperature may be just 13 light-years away. “We don’t know if life could exist on a planet orbiting a red dwarf, but the findings pique my curiosity and leave me wondering if the cosmic cradles of life are more diverse than we humans have imagined,” said Natalie Batalha, Kepler mission scientist at NASA’s Ames Research Center in Moffett Field, Calif.

Continue reading

Follow On Twitter

Current Moon Phase

CURRENT MOON