Scientists have long agreed that dark matter – the mysterious substance that makes up 85% of all matter in the universe – doesn't interact with light. But a new study suggests dark matter might not be so dark after all.

Researchers announced last week that dark matter might leave a faint splash of color on light it encounters. This "fingerprint" would be blue or red, depending on the type of dark matter the light passes through.

The tint would be too subtle to pick up with today's technology. But the researchers say the next generation of telescopes could be designed to detect it, potentially transforming our understanding of this strange substance.