Which planet is that vast object in the background? Clearly an exoplanet, not something in our system. Or is it a brown dwarf star, looks about the right size for one?

If you see the outliner windows, you can find the panet's name. (Sorry, it's in french, but you can use google translation) Ciel=Sky, Jupiter = Jupiter, Lune = Moon, Mars = Mars, Mercure = Mercury, Neptune = Neptune, Saturne = Saturn, Soleil = Sun, Terre = Earth, Uranus = Uranus, Venus = Venus.