ALMA | ESO | APEX | 2018 Apr 25
The ALMA and APEX telescopes have peered deep into space — back to the time when the Universe was one tenth of its current age — and witnessed the beginnings of gargantuan cosmic pileups: the impending collisions of young, starburst galaxies. Astronomers thought that these events occurred around three billion years after the Big Bang, so they were surprised when the new observations revealed them happening when the Universe was only half that age! These ancient systems of galaxies are thought to be building the most massive structures in the known Universe: galaxy clusters.
Using the Atacama Large Millimeter/submillimeter Array (ALMA) and the Atacama Pathfinder Experiment (APEX), two international teams of scientists led by Tim Miller from Dalhousie University in Canada and Yale University in the US and Iván Oteo from the University of Edinburgh, United Kingdom, have uncovered startlingly dense concentrations of galaxies that are poised to merge, forming the cores of what will eventually become colossal galaxy clusters. ...
These forming galaxy clusters were first spotted as faint smudges of light, using the South Pole Telescope and the Herschel Space Observatory. Subsequent ALMA and APEX observations showed that they had unusual structure and confirmed that their light originated much earlier than expected — only 1.5 billion years after the Big Bang. ...
Astronomers Witness Galaxy Megamerger
National Radio Astronomy Observatory | 2018 Apr 25
Ancient Galaxy Megamergers
Max Planck Institute for Radio Astronomy | 2018 Apr 25
A massive core for a cluster of galaxies at a redshift of 4.3 - T. B. Miller et al
- Nature 556(7702):469 (26 Apr 2018) DOI: 10.1038/s41586-018-0025-2
arXiv.org > astro-ph > arXiv:1804.09231 > 24 Apr 2018