Infrared telescopes reveal stars torn apart by black holes hidden in dust.

Supermassive black holes at the centers of active galaxies, known as active galactic nuclei or AGNs, sometimes tear apart passing stars. These bursts are called tidal disruption events. Most searches look for them using optical light or X-rays. Unfortunately, thick dust clouds block these signals, hiding disruptions happening inside dusty galaxies. To fix this, researchers examined over 10 years of mid-infraredmid-infraredA part of the electromagnetic spectrum that can penetrate dust clouds. sky scans from the WISE mission. Infrared light easily passes through cosmic dust. They looked for extreme color changes and found powerful flares in two active galaxies. One event was also visible in optical light. Years later, light measurements revealed broadened hydrogen emissions in both, but recent tests show this broad emission continued only in the optical flare. The optical flare faded unexpectedly fast. The researchers conclude both events are likely stars shredded by black holes in active galaxies, perhaps partially destroyed or torn by a smaller black hole within the disk.

Why it matters

This helps astronomers see a fuller picture of how black holes feed, especially in dusty galaxies. By detecting these events in infrared, we avoid missing those hidden from optical telescopes.

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