As we push the limits of our technology, we naturally will find the biggest, the brightest, the smallest, the most extreme, and of course the most distant objects in the universe. We are at the time in history where we are beginning to see the edges of our universe in unprecedented detail. Eventually will will stop finding the biggest, brightest, and most distant, after which point our technology will serve to improve our precision and allow us to peer within these unique objects. Astronomers have used this incredible technology to discover the most distant galaxy in the universe, forming only 650 Million years after the Big Bang.
EGS-zs8-1, as it is lovingly referred to, is a massive bright spot in the early universe, discovered in images from the Hubble and Spitzer space telescopes. Using the Multi-Object Spectrometer for Infra-Red Exploration (MOSFIRE) instrument on the W.M. Keck Observatory’s 10-m telescope, astronomers have precisely determined its distance, showing that it has already built around 15% of the mass of the Milky Way in as little as 650 Million years, compared to most galaxies we see today which formed their structure over Billions of years.
Yet despite its smaller size, it is rapidly forming stars, at a rate 80 times that of the Milky Way. The rapid formation of young blue stars in similar early-forming galaxies are thought to drive the epoch of reionization that occurred during the latter half of the first Billion years of universe expansion.
The evidence shows that even though we are finding galaxies of this size early in the universe, it also tells us that these galaxies are very different from their present-day counterparts. With a copious amount of gas and young, hot, blue, stars, these early galaxies had very unique spectral characteristics. Time will tell what a sample of the early galactic population will reveal.