JWST produces sharpest map of dark matter yet

Mar 20th 2026

Using subtle distortions in 250,000 background galaxies across a field slightly larger than the full moon, JWST produced a dark matter map about twice as detailed as Hubble’s and revealed previously unseen structures dominated by dark matter.

  • Researchers led by Jacqueline McCleary used JWST gravitational lensing of about 250,000 galaxies to map dark matter.
  • The new map has roughly twice the resolution of previous Hubble maps and reaches structures farther from Earth.
  • It reveals galaxy clusters and cosmic web filaments, including regions with little visible matter that are likely dominated by dark matter.
  • Initial comparisons broadly match the standard lambda-CDM model, while detailed analyses are still underway.
  • The dataset will help constrain cosmological parameters, probe dark matter properties, and link galaxies to their dark matter haloes.