In a few billion years, when our Sun has exhausted its supply of fuel, it will first turn into a red giant and then collapse to form a white dwarf. Some planets of our Solar System will probably survive this time (if they’re not flung out into deep space). Astronomers know this will happen – theoretically. But until now, nobody had ever found a white dwarf with a planet in orbit around it.
So, it’s understandable why researchers are so excited about the discovery of WDJ0914+1914, which is located in the constellation Cancer about 1500 light-years away. “It was one of those chance discoveries,” says the researcher Boris Gänsicke from the University of Warwick in the United Kingdom. The research group that he leads inspected about 7000 white dwarfs. With WDJ0914+1914, they noticed some peculiar features. By analyzing the slight oscillations in the starlight, the researchers found traces of chemical elements in quantities that nobody had ever observed in a white dwarf before. “We knew that there had to be something exceptional going on in this system and speculated that it might be related to some type of planetary remnant.”