Astronomers have been searching far and wide for planets beyond our solar system.
Most of the 800 confirmed discoveries have come from the Kepler space telescope, in a
region extending 3000 light years from earth.
Are there any planets to be found around nearby starsÉ possibly within traveling distance
of Earth?
The answer was no, until now.
A team of European astronomers, working at the European Southern Observatory in Las Silla,
ChileÉ has been studying a three-star system called Alpha Centauri.
The nearest is Proxima Centauri, a mere 4.2 light years away, the closest star to our
sun.
ItÕs companion, Alpha Centauri B is a star slightly smaller than our sun.
The astronomers worked with breathtaking precision.
They detected wobbles in the starÕs light, caused by tugging from the planetÕs gravity,
that amount to less than two kilometers per hour.
ThatÕs about the speed of a baby crawling.
Astronomers have speculated about planets orbiting these bodies since the 19th century.
They are the fictional location of Polyphemus, and its moon Pandora, from the movie Avatar.
Yet few astronomers today expect to find a solar system there, because planets would
be vulnerable to being hurled out into space by the gravity of the companion stars.
In fact, this one survives by literally hugging its parent starÉ at a distance much closer
than planet Mercury is to our sun.
It roasts in temperatures over 1200 degrees Celsius.
WhatÕs intriguing about the discovery is that the planet is a little larger than Earth.
ItÕs the smallest exoplanet found to date.
It seems only a matter of time till we find others just like it, somewhere in the neighborhood
of the sun, far enough out for liquid water to flow, yet still firmly held by a starÕs
gravity?