IC1101 Reaches 1.7 Million Light-Years, Still Growing in Abell 2029
Updated
Updated · IFLScience · Jul 31
IC1101 Reaches 1.7 Million Light-Years, Still Growing in Abell 2029
3 articles · Updated · IFLScience · Jul 31
Summary
New ultra-deep observations put IC1101’s diameter at about 1.7 million light-years, far above earlier estimates near 370,000 light-years and confirming it as the largest known galaxy.
Isaac Newton Telescope imaging traced where the galaxy’s stellar population sharply drops off, giving researchers a clearer edge measurement for the main body rather than its broader surrounding halo.
Chandra X-ray data also found disturbed gas around IC1101, pointing to recent material accretion and showing the galaxy is still assembling mass.
About 1 billion light-years from Earth, IC1101 spans roughly 15 Milky Ways across, contains about 3.4 trillion solar masses in stars, and hosts a black hole with tens of billions of solar masses.