Hot and Heavy ‘Teenage Galaxies’ Amaze Scientists
Like human teenagers, teenage galaxies are fun but also have their fair share of awkwardness and problems. Teenage galaxies formed around two to three billion years after the Big Bang.
The universe’s natural phenomenon left these adolescent heavens hot and full of unexpected heavy elements like nickel, silicon, sulfur, and nitrogen among others. Teenage galaxies with nickel have intrigued scientists.
Allison Strom, lead researcher and assistant professor of physics and astronomy at Northwestern University, is excited. “Never in my wildest dreams did I imagine we would see nickel.” No one has ever observed this element – silvery-white lustrous metal – in the universe before.
Teenage Galaxies and Nickel
Strom shared that they are trying to understand how galaxies grew and changed over the 14 billion years of cosmic history. “Using the James Webb Space Telescope (JWST), our program targets teenage galaxies when they were going through a messy time of growth spurts and change.”
She explained that teenagers often have experiences that determine their trajectories into adulthood and it’s the same for galaxies. Strom said that by examining the galaxy’s DNA during its teenage years can help researchers better understand how it grew and evolved into a more mature galaxy. It should be noted that a galaxy’s spectrum can reveal its key elements, such as oxygen and sulfur, which provide a window into what a galaxy was previously doing and what it might do in the future.
But no one ever talks about observing nickel. “There has to be enough of an element present in a galaxy and the right conditions to observe it. Elements have to be glowing in gas in order for us to see them. So, in order for us to see nickel, there may be something unique about the stars within the galaxies.”
These Galaxies Are Hot
Researchers were also intrigued by how hot the teenage galaxies were. Physicists can calculate a galaxy’s temperature by examining the spectra. The hottest pockets with galaxies can reach over 9,700 degrees Celsius, the teenage galaxies clock in at higher than 13,350 degrees Celsius.
Strom said this is just additional evidence of how different galaxies likely were when they were younger. “Ultimately, the fact that we see a higher characteristic temperature is just another manifestation of their different chemical DNA because the temperature and chemistry of gas in galaxies are intrinsically linked.”