Super Earth HD 40307g, just 44-light-years away in the Alpha Centauri B star system, could quite possibly be the closest to our planet yet. It’s called a “Super Earth” because the planet is 7-times larger than ours and there’s a strong possibility that it’s evenly heated all around. Continue reading for a video and more information.
The planet was found near Alpha Centauri B by the Harps instrument at the European Southern Observatory’s La Silla facility in Chile. That puts it far closer to Earth than any of the more than 840 confirmed exoplanets. Like a dance between one enormous and one tiny partner, as an exoplanet orbits its much larger host star, its gravity causes the star to move in a small orbit.
Harps and instruments like it measure the subtle change in colour – the redshift or blueshift – of the host star’s light as its orbit moves it slightly closer to and further away from Earth.