Overview
- The team analyzed emissions from about 2.6 million galaxies, stacking signals across roughly 10 billion years to build the most detailed cosmic temperature map to date.
- Average galactic dust temperatures appear to have fallen by about 10 kelvins over that period, from roughly 35 K to about 25 K.
- Because hotter dust traces more vigorous star formation, the cooling trend indicates the universe has moved past its peak pace of making new stars.
- The study merges Euclid’s optical and near-infrared data with far-infrared measurements from ESA’s retired Herschel observatory to span a broad range of wavelengths.
- The findings are available as a preprint on arXiv and have been submitted to Astronomy & Astrophysics, with conclusions described as provisional and with no practical effects on Earth for tens of billions of years.