An international collaboration has discovered two of the lowest-density giant planets ever detected: rare “super-puff” planets with densities lower than candy floss. The study—led by the University of Oxford, in collaboration with Université Côte d’Azur/Observatoire de la Côte d’Azur and the University of Birmingham—has been published in Monthly Notices of the Royal Astronomical Society.

The two planets, named TOI-791 b and TOI-791 c, orbit an F7-type dwarf star located around 1,110 light-years from Earth in the southern constellation Volans. Although both planets are roughly the size of Jupiter, they are extraordinarily diffuse: TOI-791 b has a density of just 0.038 grams per cubic centimeter, while TOI-791 c has a density of 0.047 grams per cubic centimeter.

By comparison, Jupiter’s average density is 1.33 grams per cubic centimeter, around 28 to 35 times greater.