Astronomers have discovered chemical differences between binary stars that indicate one is a cosmic cannibal that has devoured at least one planet.
Binary stars should have the same chemical composition because each star is formed from the same vast cloud of gas and dust; however earlier this year the team behind this new research discovered that the two stars of HD 81809, located around 101 light-years away, are chemically different. One of the stars, HD 81809B, has a much greater concentration of elements heavier than hydrogen and helium, which astronomers call "metals," at its surface than its binary partner HD 81809A.
