Galaxies Moving Faster Than Light

Cosmic expansion is causing distant galaxies to recede from Earth at speeds that exceed the velocity of light, a phenomenon that does not violate relativity because the expansion pertains to space itself rather than the motion of objects through space. Astronomers can still observe the ancient light emitted by these galaxies when they were much nearer, allowing researchers to study the early universe despite the super‑luminal recession rates.

Current models predict that the accelerating expansion driven by dark energy will eventually carry almost all galaxies outside the observable horizon of the Local Group. As these galaxies slip beyond the limit at which their light can reach us, the night sky will become increasingly sparse, leaving the Universe to appear almost empty to future observers.