The Fermi space telescope, designed to catch gamma rays, has seen hints of evidence for dark matter in high-energy gamma rays seen at the galaxy’s centre. The Fermi team is now opening a call for ideas on changing how it observes.
That may focus efforts on those early hints, opening the possibility to solve one of physics’ greatest mysteries. We only know of the existence of dark matter because of its gravitational effects; true to its name, it cannot be seen because it interacts only very weakly with light or normal matter.
Proving its existence, and learning something about what it is, has been a holy grail for astrophysicists since the 1930s. Julie McEnery, project scientist for the Fermi mission, said a deepening dark matter mystery has sparked the call for proposals to change the telescope’s mission.
"Some of the motivation to explore different observation strategies is from this tentative signal at the centre of the galaxy, but I think even if that wasn’t there we would want to go to our community of scientists and ask them, ‘based on what you’ve seen in the data, should we do something different?’," she told the BBC World Service programme Science in Action.
Fermi has been a tremendous success at examining some of the most high-energy processes in the cosmos, publishing a catalogue filled with details of the spinning neutron stars known as pulsars, and a wide array of "active galactic nuclei" – probably supermassive black holes.