It has been an exciting year for the discovery exoplanets! First, there was the news from Gliese 581 g, then the discovery of an Earth-like planet in Alpha Centauri. And now, scientists working in the European Southern Observatory’s HARPS apparatus have announced the discovery of the latest Super-Earth, which they believe to be the greatest candidate for extra-terrestrial life yet.
The planet is located in the HD 40307 system, an orange dwarf star that is just 42 light years from Earth. Although scientists are still not entirely sure that it’s a rocky planet, there are a number of strong indications that point towards and hospital terrestrial environment. For starters, as the sixth and farthest planet in the system, it lies within the sun’s habitable zone.
Second, the planet has a very reasonable 320 day annual cycle, which means that it receives a similar amount of solar energy compared to Earth – about 62% of what we get year round. This is positive news since most Super-Earths are situated too close to their parent stars to boast life. And last, but not least, the planet is unique amongst its near-Earth exoplanet kin in that it is not tidally locked, meaning it has a night and day cycle. Though this is not absolutely crucial to life, it is a bonus seeing as how it means one side of the planet is not constantly exposed to radiation while the other is constantly in a state of cold, life denying darkness.
Mikko Tuomi of the University of Hertfordshire in the UK, and Guillem Anglada-Escude from Germany’s University of Goettingen are chiefly responsible for this discovery. In the coming weeks, months and years, their team will be doing their best to ascertain the planet’s composition, which they hope to be rocky in nature. If this should prove to be the case, it will move to the top of likely candidates for exoplanet colonization, pushing such planets as Gliese 581 g, the most Earth-like exoplanet discovered to date, out of the top spot.
Source: Discovery News