Hubble snaps image of galaxy with mass of 3m billion suns

17 Jan 2018

The Hubble Space Telescope photographed in orbit in 1990. Image: NASA

In the distant universe, the Hubble Space Telescope has spotted a galaxy so enormous that astronomers have dubbed it ‘El Gordo’, meaning ‘the fat one’.

Trying to wrap your head around the incredible vastness of space can be challenging enough at times, but one particular galactic cluster in the distant universe is truly staggering.

NASA has revealed an image of the cluster dubbed ACT-CLJ0102-4915, which was first measured in 2012 and remains the largest, hottest and brightest x-ray galaxy cluster ever discovered.

In fact, the cluster has been nicknamed El Gordo, or ‘the fat one’ in Spanish, because it has a mind-boggling mass of 3m billion suns.

Galaxy clusters are among the largest objects in the known universe and are tightly bound by gravity as they form over billions of years.

In El Gordo’s case, observations taken by some of the largest Earth-based telescopes found that it is actually two galaxy clusters colliding at an eye-watering speed reaching millions of kilometres per hour.

El Gordo galaxy

This image was taken by Hubble’s Advanced Camera for Surveys and Wide-Field Camera 3 as part of an observing programme called RELICS (Reionization Lensing Cluster Survey). Image: ESA/Hubble and NASA, RELICS

Hubble still going on strong

Much of the mass of the cluster remains hidden, concealed as dark matter. Meanwhile, the cluster’s standard matter – mostly comprising hot gas – is being torn from the dark matter in the collision.

A research paper last month backed up this scientific understanding, showing that massive galaxies not only form incredibly quickly, but are oozing with the mysterious and little-understood form of matter.

Hubble was also in the news recently for a discovery that led to the creation of the clearest image of one of the furthest galaxies yet to be seen by humans.

Using gravitational lensing to ‘overclock’ Hubble’s technical capabilities, researchers were able to reveal an image of an embryonic galaxy that existed when the universe was just 500m years old.

Colm Gorey was a senior journalist with Silicon Republic