Exoplanet

WASP-107b was already a very weird exoplanet, with the density of cotton candy. On closer inspection, astronomers have now found that its density is even lower than previously thought, defying our current understanding of how gas giants even form.

Space is an incredibly weird place. From extreme exoplanets to stars with strange fates, clues to an old mystery and the beginnings of a brand new one, here are 10 of the weirdest astronomical discoveries that blew our minds this year.

ESA has given the go-ahead for its Atmospheric Remote-sensing Infrared Exoplanet Large-survey (Ariel) mission to progress from the study phase to the implementation phase, with an industrial contractor to build the spacecraft to be chosen in mid-2021.

There are worlds out there so weird they’d put Dr. Who writers to shame. The latest to join the ranks is K2-141b, a scorching planet where it rains rocks, winds whip at supersonic speeds and huge swaths of the surface are covered in lava oceans.

While almost every planet ever found orbits a star, there are some loners that roam the cosmos entirely on their own. Now astronomers have spotted the smallest of these “rogue planets” ever discovered, which is only the size of Earth or smaller.

Based on data from the Kepler Space Telescope and the Gaia mission, there may be up to 300 million habitable planets in our galaxy. The research refines a key factor in the Drake equation that estimates how many extraterrestrial civilizations may exist.

A team of scientists has identified two dozen exoplanets that could be more favorable to life than the Earth. These super-habitable worlds may have conditions more suitable to sustaining life for a longer period of time than our planet.

The Cheops exoplanet mission has revealed one of the hottest, most extreme planets orbiting another star. Located 322 light years away in the constellation of Libra, WASP-189 b is an ultra-hot Jupiter with a temperature so high that iron turns to gas.

Astronomers have discovered a new exoplanet that belongs in a brand new class – an “ultrahot Neptune.” Known as LTT 9779b, the planet orbits extremely close to its star, and raises questions about how such a system came to be.

NASA has discovered a strange star system where a gas giant planet is tightly orbiting a tiny white dwarf. This the first sighting of such an arrangement, raising questions about how the planet survived the star’s expansive death in the first place.

Perhaps on other planets, diamonds are as common and boring as rocks. Astronomers suggest that some planets might actually be largely made of diamonds, and now a team has calculated how such a planet could form and how it would be structured.

For the first time, astronomers have used a machine learning algorithm – a form of self-teaching AI – to confirm the existence of 50 new exoplanets in data collected by the now retired Kepler space telescope.