“Being able to find three Earth-mass planets around a single star really makes the point that not only may many stars have one Earth, but they may very well have a couple of Earths,” said Alan boss, a planet formation theorist at the Carnegie Institution of Washington in Washington, D.C.
Hiding in our galaxy is the twin of Earth, at least that is what astronomers believe when they announced the discovery of three super-Earths on June 16, 2008. What was found were worlds larger and more massive than our own planet yet were considered to be small enough to be rocky while orbiting a single star. Some of these spectacular finds were nothing but gas giants called hot Jupitersextremely easy to find. Orbiting close to their stars, approximately 300 such worlds have been found since the 1990s.
Geoff Marcy, one of the top world planet hunters of the University of California at Berkeley, has been quoted as saying, “So far we’ve found Jupiters and Saturns, and now our technology is becoming good enough to detect planets smaller, more like the size of Uranus and Neptune, and even smaller. “Such high name scientists are extremely optimistic that a near twin of Earth will be located in another star system within the next five years or so. Boss feels that the astronomy field knows that Earth-like planets are presently orbiting the very same stars we gaze at during the night, even though we cannot see them with our eyes. This is made possible with two standard techniques developed to locate other worlds: radial velocity and the transit method.
RADIAL VELOCITY METHOD
This method attempts to see slight wobbles in the motion of a star, due to the gravitational tug of an orbiting planet. The advantage of this method is because it detects massive planets close to their host stars.
A dimming of light when a planet passes directly in front of its host star is considered more haphazard, it works excellent when telescopes scan the light from any number of stars simultaneously.
LIMITATIONS OF BOTH METHODS
Both the transit and radial velocity methods have limitations in their finding abilities, due to the fact they block out the overshadowing light of the host star. The astronomers use the Sun is an example, with it being 100 times larger; 300,000 times more massive; and up to 10 billion times brighter than Earth. A panel of astronomers, upon completion of their final report of the Exoplanet Task Force, has written, “Detecting Earth in reflected light is like searching for a firefly six feet from a searchlight that is 2,400 miles distant.” The more and more the spectrometers and digital cameras are upgraded as they are attached to newer telescopes, the eyes of both astronomers and scientists are able to view the tiny stellar wobbles and dips in starlightall from the tiniest of low-mass planets and stars.