You may have noticed that whenever a new exoplanet is detected a long debate about its habitability almost instantly emerges. But a new study suggests that the discussion about the ability of newfound Earth-sized worlds to support life is nothing more than ‘idle speculation.’
This week, we learned that three Earth-sized exoplanets have been spotted orbiting a dwarf star 40 light years away. Headlines used ‘Earth-sized’ and ‘Earthlike’ interchangeably when describing the space bodies. But a group of scientists claims that there’s a huge difference between the two terms.
A separate study has just revealed that two of the newly found planets are probably too scorched to sustain life. So, reports on habitability were greatly exaggerated.
“All of the stuff about habitability, surface environments, etc., is merely idle speculation and conjecture,”
said Greg Laughlin, lead author of the study and astrophysicist with the University of California, Santa Cruz.
Laughlin noted that even when it comes to our solar system there had been a lot of speculation on the surface features of some space bodies. Oftentimes, direct observations proved scientists they were wrong. The most notorious case is Pluto which was proven to be much more geologically diverse than most researchers had expected.
In order to be deemed Earthlike a planet needs to meet a series of criteria and scientists haven’s reached a consensus on what those criteria may be. The exoplanets may need to have the same size and temperature as our planet. They may also need to orbit a star similar to the sun or have an Earthlike atmosphere and geomorphology.
These details vary from one research team to another and scientists remain divided.
Furthermore, scientists cannot measure all the variables on a distant exoplanet. They can only know for sure its size, orbit, and maybe surface temperature if the planet is close enough to its host star to remain tidally locked, i.e. to have a side eternally facing the star.
In Laughlin’s opinion, Earthlike doesn’t mean seas, quakes, dolphins and stock exchanges. An Earthlike planet should be Earth-sized and receive the same heat and energy from its host star like our planet does.
Still, the research team hopes that further study of the newfound planetary system would clarify things more. And the trio of exoplanets is a perfect subject of study due to its proximity to our planet and its star’s dim light, which should not obstruct observations.
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