Scientists have produced the most detailed…

Scientists have produced the most detailed map yet of the dark matter that threads through the Universe, revealing how this invisible component has guided the formation of galaxies, stars and planets over cosmic time. The new map, created with observations from NASA's James Webb Space Telescope and published in Nature Astronomy, traces dark matter in a region of sky in the constellation Sextans covering an area about 2.5 times larger than the full Moon.

The study, jointly led by Durham University in the UK, NASA's Jet Propulsion Laboratory and the Ecole Polytechnique Federal de Lausanne in Switzerland, uses Webb data to confirm earlier dark matter measurements and to add finer structure and new clumps not seen before. Astronomers think that when the Universe began, both dark matter and normal matter were sparsely distributed, but dark matter clumped together first under its own gravity and then pulled in ordinary matter, setting up the large-scale structure in which galaxies could form.

Dark matter does not emit, reflect, absorb or block light and passes through normal matter largely unnoticed, but its presence reveals itself through gravity, which curves space and deflects light from background galaxies.