We know thousands of them, and we are discovering more and more quickly: exoplanets sometimes turn out to have strange properties. We propose to look at some of them in this episode of Swipe Into Space.
In 2019, a 17-year-old high school student, Wolf Cukier, then an intern at the NasaNasa for only three days, spots a anomaliesanomalies. In data collected by a satellite launched a year ago, a mysterious object eclipseeclipse the lightlight issued by a starstar doubles periodically. After several hypotheses, the answer arrives: it’s a new planet he has just discovered!
Just like Tatooine in Star Warsit is a circumbinary planet, that is to say in orbitorbit around two stars. A rather exceptional particularity, because of the more than 4,000 exoplanetsexoplanets recorded, less than 20 have two suns! Now known as TOI 1338b, this new planet would require a 1,300-year journey to the speed of lightspeed of light to reach it!
Many unusual planets
Most of the exoplanets discovered are outside the habitable zone. There are very often extreme conditions, as on Gliese 581C. Located 20 light yearslight years from the Earth, this planet gravitationally locked with its star always shows the same face to it, just like the Moon with the Earth. So much so that its sunlit side would char you instantly, while its shaded side would freeze you in place. But on his equatorequatorthe temperature would constantly fluctuate between 0°C and 40°C, precisely enough to harbor life.
Another planet surprised the astronomersastronomers, who studied its chemical composition. Called 55 Cancri e, it contains a concentration of carbon that is far too high, which researchers have associated with a heart filled with diamonds! This very particular form of carbon is formed hundreds of kilometers under the terrestrial mantleterrestrial mantleunder conditions of temperature and pressionpression very precise. This is why today it is impossible to create them artificially. But on 55 Cancri e, the abundance of these diamonds would represent a massemasse greater than that of the Earth!
