Hubble Discovers Earliest Sources of Light in Universe
The Hubble telescope isn’t just for taking incredible photos of psychedelic space clouds – although it is pretty good at it. The Hubble space telescope has a variety of imaging technologies which allow it to ‘see’ various types of radiation, not just the wavelengths of light usually visible to our naked eyes.
The Hubble Space Telescope: envy of blacklight poster artists everywhere.
Astronomers at the University of Texas have now devised a technique known as “wavelet decomposition” which masks certain wavelengths of light in order to filter out the light generated by galaxy clusters closest to the Hubble telescope. By filtering out this foreground light, astronomers are able to see much, much farther into the universe and detect objects which were previously invisible. So far, the UT astronomers have discovered 167 new galaxies which are up to ten times fainter than all previously discovered galaxies.
One of the newly discovered galaxy clusters, the Abell 2744 cluster.
In a groundbreaking discovery, the researchers believe some of the galaxies detected by this new technique are thought to be responsible for the process known as reionization which followed the Big Bang. Reionization caused most of the matter (mostly hydrogen) in the Universe to change state and become ionized, converting dark matter into the baryonic matter we are familiar with. According to their data published in The Astrophysical Journal, the researchers believe these faint, early galaxies could be responsible for this reionization:
Faint galaxies in the early universe could have been responsible for reionization. […] Our study demonstrates the power of gravitational lensing to study the early universe and directly observe the very faintest galaxies that powered reionization.
If anything ever did really ‘let there be light,’ it was this process of reionization. By identifying the galaxies which could possibly be responsible for reionization, these astronomers have found what could be the very first sources of light in the known universe. While it might not be a bearded man in a white robe, it’s still pretty revolutionary discovery for our understanding of the universe and its formation.