Scientists Discover "Earth-Sized" Planet

This seems an appropriate post for Earth Day, as it has been revealed that Astronomers have discovered a planet outside our solar system that is similar in size to Earth.

An American expert called the discovery of the tiny planet “extraordinary.” (Nice!)

This is an important revelation, as most planets discovered outside our solar system tend to be around the size of Jupiter, which dwarfs the Earth by huge measures.  It is said that Jupiter could swallow the Earth over 1,000 times.

While this new planet, called Gliese 581 e,  sits too close to its sun to support life (it is simply far too hot), it is a major discovery in that researchers now know that nature does make planets roughly the size of Earth. Therefore, it is likely that there could be another planet in the galaxy that could support life.

An artist’s impression of ‘Planet e’ , forground left, released by the European Organisation for Astronomical Research in the Southern Hemisphere Tuesday April 21, 2009. Exoplanet researcher Michel Mayor announced Tuesday the discovery of the lightest exoplanet found so far. The planet, ‘e’, in the famous system Gliese 581, in the constellation of Libra and 20.5 light years (192 trillion km or 119 trillion miles) away, is only about twice the mass of Earth. The team also refined the orbit of the planet Gliese 581 d, (coloured blue in image) first discovered in 2007, placing it well within the habitable zone, where liquid water oceans could exist. These discoveries are the outcome of more than four years of observations using the most successful low-mass-exoplanet hunter in the world, the HARPS spectrograph attached to the 3.6-metre ESO telescope at La Silla, Chile. (AP Photo/ European Organisation for Astronomical Research in the Southern Hemisphere)

According to the AP:

Geoff Marcy of the University of California, Berkeley, praised the find of Gliese 581 e as “the most exciting discovery” so far of exoplanets — planets outside our solar system.

“This discovery is absolutely extraordinary,” Marcy told The Associated Press by e-mail, calling the discoveries a significant step in the search for Earth-like planets.

While Gliese 581 e is too hot for life “it shows that nature makes such small planets, probably in large numbers,” Marcy commented. “Surely the galaxy contains tens of billions of planets like the small, Earth-mass one announced here.”

Gliese 581 e is located in the constellation Libra and orbits around the star Gliese 581.  Like other planets circling that star — scientists have discovered four so far — Gliese 581 e was found using the European Southern Observatory‘s telescope in La Silla, Chile.

The telescope has a special instrument which splits light to find wobbles in different wavelengths. Those wobbles can reveal the existence of other worlds.