Free Astronomy Magazine July-August 2019

55 JULY-AUGUST 2019 SPACE CHRONICLES and precisely disentangles the light from HR8799e’s atmosphere and the light from its parent star. HR8799e is a ‘super-Jupiter’, a world unlike any found in our Solar Sys- tem, that is both more massive and much younger than any planet or- biting the Sun. At only 30 million years old, this baby exoplanet is young enough to give scientists a window onto the formation of plan- ets and planetary systems. The exo- planet is thoroughly inhospitable — leftover energy from its formation and a powerful greenhouse effect heat HR8799e to a hostile tempera- ture of roughly 1000 °C. This is the first time that optical in- terferometry has been used to re- veal details of an exoplanet, and the new technique furnished an exquis- itely detailed spectrum of unprece- dented quality — ten times more detailed than earlier observations. The team’s measurements were able to reveal the composition of HR- 8799e’s atmosphere — which con- tained some surprises. T his wide-field image shows the surroundings of the young star HR8799 in the constellation of Pegasus. This picture was created from material forming part of the Digitized Sky Survey 2. [ESO/Digitized Sky Survey 2. Acknowledgement: Davide de Martin]