Caption

Sometimes, stars can be stripped away from globular clusters as they orbit a massive galaxy. Researchers have identified several instances in our own Milky Way galaxy – and they’ve also spotted gaps between these looping tendrils. What caused those gaps? One possibility: a substance known as dark matter.

Following the launch of the Nancy Grace Roman Space Telescope, astronomers will use its vast, high-definition images to spot many more tidal streams – and potentially their accompanying gaps – in nearby galaxies for the first time.

A prime candidate is our neighbor, the Andromeda galaxy, which appears in the illustration above. Soon, not only will researchers be able to identify tidal streams in Andromeda, they may also be able to use Roman’s fine resolution to pinpoint more properties of this mysterious substance.