Friday, 13 May 2016
Earth’s Twin Is Still Missing, Despite Discovery of Over 1, 200 New Exoplanets
NASA has announced that its Kepler space observatory has found 1,284 new exoplanets, including roughly 550 Earth-sized ones. Of these, nine may orbit their star in the habitable zone or at a distance at which water is expected to be in liquid form but not too hot to evaporate.
Commenting on the discovery, Andrew Norton, Professor of Astrophysics Education at The Open University, writes:
“The latest announcement is an impressive piece of work, and the discovery of so many new exoplanets is stunning. It is increasingly clear that planets orbit stars as a rule – not an exception. While astronomers still haven’t found an exact twin of the Earth, the rapid pace of discoveries is surely a sign that it is just a matter of time until they do.”
But what if Earth really is unique, as some researchers have suggested, and there’s no place like home elsewhere in the universe?
The wildest speculations have put the number of Earth-like planets at over 100 billion billion, but that is based more on wishful thinking than on facts.
We should keep in mind that Venus and Mars orbit the Sun in the habitable zone, and just look how habitable they are.
Moreover, the goldilocks zone around some stars may be smaller than we assumed, and some habitable planets might not be habitable after all.
Research suggests that even Kepler-438 B, once touted as the most Earth-like exoplanet, might not be habitable.
Norton, Andrew. 2016. More than 1,000 new exoplanets discovered – but still no Earth twin. The Conversation (11 May).