For the first time ever, astronomers caught a glimpse of the earliest stages of massive galaxy construction.
Scientists are calling this little baby elliptical galaxy “Sparky.” Its discovery was made using combined observations and data from two space telescopes, a space-based observatory, and an Earth-based observatory: NASA's Hubble and Spitzer space telescopes, the European Space Agency's Herschel space observatory, and the W.M. Keck Observatory in Hawaii.
NASA describes the galaxy's location as having a “dense galactic core blazing with the light of millions of newborn stars that are forming at a ferocious rate.” Researchers say Sparky is an impressive factory, producing stars at a rate of approximately 300 stars a year. That puts the Milky Way’s roughly 10 stars-per-year production to shame. But scientists believe this production rate will slow as the galaxy ages.
Despite its impressive star production rate, Sparky is tiny compared to our galaxy. Researchers estimate that Sparky is 6,000 light-years across. The Milky Way measures approximately 100,000 light-years across. But Sparky’s a growing boy. He’ll get bigger.
“We really hadn't seen a formation process that could create things that are this dense," explains study lead author Erica Nelson of Yale University. “We suspect that this core-formation process is a phenomenon unique to the early universe because the early universe, as a whole, was more compact. Today, the universe is so diffuse that it cannot create such objects anymore.”
Scientists are excited about the observation and the details it provides about early galaxy formation.
"I think our discovery settles the question of whether this mode of building galaxies actually happened or not," said study team member Pieter van Dokkum of Yale University. "The question now is, how often did this occur?"
This research, published in a paper titled “A massive galaxy in its core formation phase three billion years after the Big Bang,” appears in the August 27 issue of the journal Nature.
