NASA Explains Dark Matter's Role in Cosmic Structure and Gravity

NASA News Releases featured an Astronomy Picture of the Day on October 25, 2026, which presented a dark matter map to illustrate the pervasive nature of dark matter in the cosmos. The gravity exerted by unseen dark matter is cited as the leading explanation for several observed phenomena, including the swift rotation of galaxies, the rapid orbiting of galaxies within clusters, the strong deflection of light by gravitational lenses, and the distribution of visible matter.

A computer simulation, sourced from the American Museum of Natural History's Hayden Planetarium Space Show, Dark Universe, depicted complex filaments of dark matter, rendered in black, spread throughout the universe resembling spider webs, while less common clumps of familiar baryonic matter were colored orange. These simulations reportedly show good statistical alignment with astronomical observations.

However, NASA News Releases noted that dark matter, despite being a strange substance in an unknown form, is no longer considered the most mysterious source of gravity in the universe. That distinction is now attributed to dark energy, which is described as a more uniform source of repulsive gravity that appears to be dominating the expansion of the entire universe.