El Gordo (galaxy cluster)
El Gordo (lit. The Fat One) (ACT-CL J0102-4915 or SPT-CL J0102-4915) is the largest distant galaxy cluster observed at its distance or beyond, as of 2011. As of 2014, it held the record for being the largest distant galaxy cluster to have been discovered with a mass of slightly less than three quadrillion solar masses although later its mass was reduced to about 2.1 quadrillion solar masses with a 10% uncertainty. It was found by NASA's Chandra X-ray Observatory, the Atacama Cosmology Telescope (funded by the National Science Foundation) and the European Southern Observatory's Very Large Telescope.
| ACT-CL J0102-4915 | |
|---|---|
El Gordo consists of two separate galaxy subclusters colliding at several million kilometres per hour. | |
| Observation data (Epoch J2000.0) | |
| Constellation(s) | Phoenix |
| Right ascension | 01h 02m 52.50s |
| Declination | −49° 14′ 58.0″ |
| Redshift | 0.87 |
| Other designations | |
| El Gordo, ACT-CL J0102-4915, SPT-CL J0102-4915 | |
This galaxy cluster, officially named as, 'ACT-CL J0102-4915', has been given a 'nickname' by the researchers as 'El Gordo', which stands for "the Fat One" or "the Big One" in Spanish. It is located more than 7 billion light-years from Earth.
Findings and results on 'El Gordo' were announced at the 219th meeting of American Astronomical Society in Austin, Texas.