The incredible image of an exoplanet forming around a star

A newborn planet has been observed for the first time by astronomers. The planet was discovered by a team from the Max Planck Institute for Astronomy in Heidelberg, Germany using ESO’s SPHERE instrument. Called PDS 70b, the young world can be identified as the bright spot to the right of the blackened center of the image above.

The SPHERE instrument equips one of the four telescopes of the Very Large Telescope of the European Southern Observatory (VLT) in Chile. This tool was designed to find exoplanets around stars near the Sun. Commissioned in 2014, SPHERE uses extreme adaptive optics: it has a mirror that corrects the effects of atmospheric turbulence more than 1,200 times per second and at a nanometric scale. It is also equipped with a coronograph that masks the light of the observed star and thus reveals its close environment usually masked by its brightness. This observation technique allowed after some tests to make images of the young planet.

This planet, not yet completely formed, revolves around its star PDS 70 three billion kilometers away. Almost the distance between Uranus and the Sun. This star bud is clearly visible in this image obtained by SPHERE: a luminous point, to the right of the center of the image, where the star is masked by the coronagraph. Analysis of the data indicates that PDS 70b is a giant gas planet with a mass of several Jupiter. The surface of the planet has a temperature of about 1000 ° C and the study of its spectrum reveals the presence of a turbid atmosphere encircling it.

The SPHERE data have also allowed scientists to study in detail the protoplanetary disk that surrounds PDS 70. It is a temporary structure composed of gas and dust from which the planets are formed. The PDS 70 disk has a very special structure with a giant hole inside. For a long time, astronomers suspected that such holes are caused by the interaction between the disk and a planet in formation. They have finally gotten the proof. These results will help refine the search for new exoplanets and better understand the process of their formation.

Carl Frantz

Polyglot, humanitarian, Carl was born in Germany but raised in the USA. He writes mostly on tech, science and culture.