This intergalactic filament is 50 million light-years long, the longest I’ve ever seen.

An optical image of the Abell 3391/95 system in which scientists observed the longest filament ever observed. (Image credit: Reiprich et al., Astronomy & Astrophysics)

The extraordinarily long strands of hot gas known as intergalactic filaments connect and surround galaxies and groups of galaxies across the cosmos – and scientists have just discovered the longest so far.

intergalactic filaments form a cosmic network that stretches across the observable universe. Within this structure, galaxies are arranged in a network-like pattern, connected and surrounded by these filaments.