3º Ano Ensino Médio - 2012
Autor: Alexandre Nakamoto | Publicado: 2012-02-10T08:04:00-02:00

Scientists discover another Earth!By Catholic Online (NEWS CONSORTIUM)12/7/2011Catholic Online  (www.catholic.org)Planet likely to have liquid water and an average temperature of 72 degrees F.Scientists claim to have discovered another earth outside of our solar system and  it may be habitable. The discovery is the product of the Kepler Space Telescope's search for planets outside of our solar system.
LOS ANGELES, CA (Catholic Online) - The planet in question is known as Kepler-22b. It's not a particularly exciting name, but employs a naming system that is practical for a scientific project that has already found 2,326 potential planets after just 16 months of exploration. While these discoveries will still need to be confirmed, they easily quadruple the number of planets now known to exist outside of our solar system.

Until recently, astronomers could only speculate whether or not planets orbited other stars. The answer was universally thought to be yes, but it was not known if every star would have planets, nor was it well known if any of those planets would be like Earth.

Recent discoveries now suggest that our solar system is rather ordinary; that other stars seem to have planets as a matter of course, and that around at least some of those stars, the planets may be habitable, meaning their environments could be much like Earth's.

No telescope can yet see the majority of these planets directly. Instead, planets are detected almost automatically, with the Kepler telescope monitoring the light from individual stars. As planets pass between the telescope and their parent star, they subtly dim the starlight that reaches the telescope. This dimming can be detected by the ultra-sensitive equipment on board the Kepler telescope. Scientists then pour over the data for each star, searching for patterns that are the telltale signature of planets passing in front of stars.

Based on the pattern of dimming, and just how much the star dims, as well as examining wobbles in the star -- produced by the influence of large planets, they can calculate the mass of these extrasolar planets as well as their relative position in orbit around their parent stars.

What they have found to date is exciting.

Kepler-22b orbits its parent star in a region which scientists refer to as the "Goldilocks zone." The Goldilocks zone is that space around a star where liquid water can exist. A planet which orbits too close to its star will be too hot for liquid water to exist. Conversely, a planet orbiting too far from the star will have all of its water frozen. Since liquid water is thought to be a prerequisite for life, scientists are keenly interested to find planets in the Goldilocks zone.

Kepler 22b appears to be in that zone. The planet is approximately 4 times the size of Earth, which means that while it probably has liquid water, and its average temperature is around 72°F, its gravity will be much greater than Earth's. That means you'd weigh a lot more on Kepler 22b, than on Earth. Still, extreme gravity will not necessarily preclude the presence of life on such a planet.

It is a question which astronomers have asked for centuries. Has God created other life in the universe besides ours? With the discovery of Kepler-22b, scientists may be just one tiny step closer to answering that question, although it is unlikely we will know for sure -- at least in our lifetime. 

© 2011, Catholic Online. Distributed by NEWS CONSORTIUM.