1. TrES-2b – blacker than coal.
Jupiter-sized TrES-2b is almost pitch black, reflecting just 1% of the light that falls on it. The only break from its darkness is a faint red glow caused by its temperature of nearly 1000°C.
2. TrES-4 – so big it shouldn’t exist.
TrES-4 is 70% bigger than Jupiter but less massive, meaning its has a really low density — about the same as balsa wood. Current theories can’t explain how a planet can be so big at such a mass. Scientists think its atmosphere is probably escaping, like the tail of a comet, because it’s not massive enough to hold on to it.
3. CoRoT-7b – raining rock onto a surface of lava.
CoRoT-7b orbits its star once every 20 hours and has surface temperatures ranging from 2000°C on the side facing its star to -200°C on the dark side. It could harbour oceans of boiling lava and rain made of rock. One study suggests it might even be the remnant of a Saturn-sized gas giant whose outer layers have been destroyed by its star.
4. WASP-12b – eaten alive by its star.
WASP-12b is a Jupiter-sized planet that’s got a little too close to its host star, and now its atmosphere is being ripped off at a rate of about 189 quadrillion tonnes per year. It’s not likely to last much more than another 10 million years.
5. Kepler 10b – small, but deadly.
One of the smallest rocky exoplanets found at just 1.4 times the size of the Earth, Kepler 10b sounds like it could be pretty similar to our planet. But then you realise it’s 20 times closer to its star than Mercury is to the sun. And the same side of the planet faces the star at all times, creating extreme temperature differences between the day and night sides. On top of all that, flecks of silicate and iron might boil off its day side and get swept away by radiation.
6. HD 189733b – sideways glass rain.
HD 189733b is pale blue in colour, but that’s where the similarities to Earth end. It has howling winds of around 7000kph and scientists think silicates could condense in its atmosphere, forming glass rain that would fall sideways.
8. Kepler 16b – a real-life Tatooine.
One sun seems normal to us, but most stars come in twos. In 2011 NASA found its first planet orbiting two stars, like Luke Skywalker’s home planet does in Star Wars. One of its stars is similar to our sun, just a little smaller, and the other is a red dwarf.
11. Kepler-36b and Kepler-36c – interacting planets.
An Earth-sized planet and a Neptune-sized one both orbit the same star in this system. Gravity pulls them close together once every 97 days. They’ll never collide, but the mass of each planet squeezes and stretches the other when they get close.
12. PSR 1257 b and PSR 1257 c – orbiting a dead star.
The first exoplanets ever found, these two orbit a rapidly spinning and super dense star almost entirely made up of fundamental particles called neutrons. The star was formed in a supernova that probably also stripped these two planets of their outer gas layers, leaving two rocky cores.