Astronomers from Lund University in Sweden have now found the explanation to a recent mystery at the centre of the Milky Way galaxy: the high levels of scandium discovered last spring near the galaxy’s giant black hole were in fact an optical illusion.
Last spring, researchers published a study about the apparent presence of astonishing and dramatically high levels of three different elements in red giant stars, located less than three light years away from the big black hole at the centre of our galaxy. Various possible explanations were presented, for example that the high levels were a result of earlier stars being disrupted as they fall into the black hole, or a result of debris from the collisions of neutron stars.
Now another group of astronomers from Lund University among others, in collaboration with UCLA in California, have found an explanation for the high levels of scandium, vanadium and yttrium. They argue that the so-called spectral lines presented last spring were actually an optical illusion. Spectral lines are used to find out which elements a star contains — by using its own light.
“These giant red stars have used up most of their hydrogen fuel and their temperatures are therefore only half of the sun’s,” says Brian Thorsbro, lead author of the study and doctoral student in astronomy at Lund University.