The discovery of another ‘Earth-like’ planet is remarkable for more than one reason. Ever since the first exo-planet (a planet outside our solar system) was detected in 1995, astronomers have spotted distant worlds at regular intervals, including some multi-planet systems. This apparent spurt in planet discoveries of late is not surprising, given the indirect ‘wobble’ technique that planet hunters use to zero in on these planets. The gravitational tugs of a planet circling a star induce a wobble in the star’s orbit that telescopes can make out. The technique does not actually give a visual image of the planet, but only measures its gravitational effect on the star. Since a planet must make a complete orbit of the star for astronomers to ascertain its presence and characteristics, and since astronomers began a focused search only a little over a decade ago, stars with revolutions of around 10 years are now being confirmed.
The Swiss astronomers who made the latest discovery say that it orbits a red dwarf some 120 trillion miles away. This is relatively nearby in galactic terms. And although its diameter, atmospheric make-up, and contents have yet to be confirmed, from all accounts it could be just the right size for a life-harbouring planet, especially since it appears to have water in liquid form. If further studies confirm this, it would be a big step in the search for life elsewhere in the universe. For each such discovery takes us a step closer to understanding the development of our own solar system and increases manifold the possibility of finding other Earth-like planets. The goal is to ultimately find potentially habitable planets and probe them for signs of life.
The growing list of planets orbiting stars similar to the sun suggest that planet formation in the galaxies are much more common than scientists have ever reckoned. This makes it almost inconceivable that only Earth has life, and quite unlikely that only it has intelligent life.