#gravitational-lensing

#gravitational-lensing

This system is truly extraordinary. We are seeing the radio equivalent of a laser halfway across the universe. This galaxy acts as a lens, the way a water droplet on a window pane would, because its mass curves the local space-time. So we have a radio laser passing through a cosmic telescope before being detected by the powerful MeerKAT radio telescope.

This system is truly extraordinary. We're seeing the radio equivalent of a laser halfway across the universe. Fundamentally, masers and lasers are focused beams of light in the same frequency. In the realm of astrophysics, these can arise from clouds of dust being excited into a higher energy state from the light emitted by other sources, like stars and black holes.

ESA / Webb, NASA & CSA, G. Mahler Day 7 of the 2025 Space Telescope Advent Calendar: A Warped View Through an Einstein Ring. You are seeing two galaxies here, one in front of the other. The more distant spiral galaxy appears warped and distorted due to the gravitational lensing occurring around a massive, much closer galaxy, which is part of galaxy cluster SMACSJ0028.2-7537.