Finding another planet like Earth growing closer

Posted: Sep. 26, 2011 11:28 am Updated: Nov. 29, 2014 4:15 am


AFTER THOUSANDS of years of searching and facing the possibility that the Earth and its sister planets might be alone in the universe, the first extra-solar planet -- a planet outside our solar system -- was discovered and its existence confirmed.

As of 2007, 242 "exoplanets" had been found, most of them gas giants in impossibly uninhabitable orbits. The search for Earth-like planets in the so-called "Goldilocks zone," not too hot, not too cold and capable of containing liquid water, the key to life, continued.

As the search continues, with more and better instruments, the number of exoplanets is more than 600 and there are 1,200 candidate exoplanets waiting for confirmation.

The discoveries got stranger. This summer astronomers discovered a planet five times the size of Earth roaming through the Milky Way that may well be one large diamond.

And the discoveries started coming in batches. European astronomers recently announced the discovery of 50 new planets outside our solar system, including 16 planets with Earth-like possibilities because their mass indicates they are made out of rock, not gas.

But one of those planets really stood out to the astronomers: A "super-Earth," 3.5 times the size of our own. It has the right mass to be rock and, moreover, it is in the Goldilocks zone, only the second such planet located.

The astronomers believe the planet, HD88512 in the constellation Vela 36 light-years away, may have water and an atmosphere as well. If so, the temperatures would range around 85 to 120 degrees and it would be extremely muggy. Comparisons with Washington, D.C., in July are a little unfair, but there are areas of equatorial Africa that would fit that bill.

The discoveries should start coming faster and in greater detail. NASA has its planet-hunting Kepler space telescope in operation and next year the European Extremely Large Telescope, said to be capable of finding life around the nearest stars, goes into operation.

Finding our twin may now only be a matter of time. Sadly, when we do find it, even a robotic probe would take many lifetimes to reach even the closest star systems.