Astronomers have discovered an atmosphere around the super-Earth planet GJ 1132b. This marks the first detection of an atmosphere around an Earth-like planet other than Earth.
Astronomers used the 2.2 m ESO/MPG telescope in Chile to take images of the planet’s host star GJ 1132.
They were able to measure the slight decrease in brightness as the planet and its atmosphere absorbed some of the starlight while transiting (passing in front of) the host star.
The planet GJ 1132b, orbits the very low-mass star GJ 1132 in the Southern constellation Vela, at a distance of 39 light-years from Earth.
The team used the GROND imager at the 2.2 m ESO/MPG telescope of the European Southern Observatory in Chile to observe the planet simultaneously at seven different wavelength bands spanning the optical and near-infrared.
As GJ 1132b is a transiting planet, it passes directly between Earth and its host star every 1.6 days, blocking a small fraction of the star’s light. From the amount of light lost, astronomers can deduce the planet’s size — in this case only 1.4 times that of Earth.