VISUAL ARCHIVE / IMAGE STORY
When Gas and Invisible Mass Part Ways
A proposed collision can separate the ingredients that ordinarily share a galaxy.
An ancient collision may have separated gas from dark matter, leaving material that could form galaxies. AI-generated concept illustration; the violet halos represent invisible matter and are not observed light.
THE OBSERVATION
What we can actually see.
Stellar motions constrain mass within the measured parts of DF2, DF4, and DF9. A bullet-dwarf collision is one proposed formation history; the visible violet halos symbolize dark matter rather than radiation that a telescope has photographed.
THE ILLUSTRATION
What the artwork imagines.
The composition visualizes this idea: A proposed collision can separate the ingredients that ordinarily share a galaxy. An ancient collision may have separated gas from dark matter, leaving material that could form galaxies. AI-generated concept illustration; the violet halos represent invisible matter and are not observed light.
FROM THE ILLUSTRATED ARTICLE
The story that inspired it.
The article follows faint galaxies in the NGC 1052 field whose measured motions require little additional dark matter in the studied regions. It compares a collision-separation hypothesis with competing formation histories instead of treating the origin as settled. This frame focuses on a proposed collision can separate the ingredients that ordinarily share a galaxy.
Read The Galaxies That Lost Their Dark MatterCHECK THE RECORD
The image interprets the research below. Follow the original work for the measurements and limits behind the scene.
Keim and colleagues: A Third Galaxy Missing Dark Matter along a Trail of Galaxies in the NGC 1052 Field (2026) Van Dokkum and colleagues: A trail of dark-matter-free galaxies from a bullet-dwarf collision, Nature (2022) Lee and colleagues: Multiple Beads on a String, The Astrophysical Journal (2024) NASA Science: Dark Matter NASA Hubble: Mystery of Galaxy’s Missing Dark Matter Deepens (2021) Chandra: The Bullet Cluster Keim and colleagues: Kinematic Confirmation of a Remarkable Linear Trail of Galaxies in the NGC 1052 Field (2025) Tang and colleagues: Hubble and Webb distances to the NGC 1052 trail (2026) Hammer and Yang: Tidal origin of dark-matter free dwarf galaxies in the NGC 1052 group (2026)OTHER IMAGE STORIES
Keep looking.
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Two Kinds of Matter, Different Responses
The Mark Shared by Titan and PlutoEXPLORE IN 3D / MAP 13
Look beyond one galaxy’s visible stars
Move through an illustrated cosmic neighborhood and compare galaxy scales. The explorer does not measure dark-matter halos or simulate the proposed collision that produced the NGC 1052 trail.
Open Universe map