Hubble Telescope Helps Find Six “Dead” First Universe Galaxies

You would think that the large galaxies in the early universe would have had a lot of “fuel” for new stars, but a recent discovery suggests that was not always the case. Astronomers using the Hubble Space Telescope and the Atacama Large Millimeter / Submillimeter Array (ALMA) found six primitive galaxies (around 3 billion years after the Big Bang) that were unusually “dead” – that is, that they lacked cold. the hydrogen necessary for the formation of stars. It was the peak period for star births, according to lead researcher Kate Whitaker, so the disappearance of this hydrogen is a mystery.

The team found the galaxies through a strong gravitational lens, using clusters of galaxies to bend and amplify light from the early universe. Hubble identified where stars had formed in the past, while ALMA detected cold dust (a substitute for hydrogen) to show where stars would have formed if the necessary ingredients had been present.

It is believed that the galaxies have since expanded, but not by the creation of stars. Rather, they developed through mergers with other small galaxies and gases. Any training after that would have been limited at best.

The results are a testament to the combined power of Hubble and ALMA, not to mention the capabilities of Hubble decades after its launch. At the same time, it highlights the limits of technology and human understanding by raising a number of questions. Whitaker noted that scientists don’t know why the galaxies died so quickly, or what happened to cut the fuel. Was the gas heated, expelled, or simply consumed quickly? It may take some time to provide answers, if answers are still possible.