Did you know that some galaxies in space shine brighter than others? In fact the Milky Way, our spiral-shaped home in the Universe, is dim compared to some other galaxies.
We didn't know much about the brightest galaxies in the universe until recently. Thanks to submillimeter telescopes and the relatively new field of submillimeter astronomy, we can now “see” objects in the universe that were previously inaccessible — specifically objects at the non-visible wavelengths between .03mm and 1.0mm. Submillimeter astronomy has revealed submillimeter galaxies, also referred to as submms or SMGs. SMGs are thought to be the most brilliant galaxies in the universe.
PHOTO BREAK: 10 places on Earth that resemble alien planets
While scientists concluded that SMGs were massive and luminous, there were mysteries as to how they function and why they shine so brightly. However, new research conducted at Haverford College and published in Nature explains how these galaxies operate and how they are able to produce so much light.
Computational astrophysicist Desika Narayanan led a team who created a new SMG model using supercomputer technology. The computer recreated a portion of the early universe allowing the scientists to see how galaxies like SMGs formed and how they acted and grew.
Popular Mechanics describes the way in which these galaxies function, referring to them as “convection ovens.” They recycle energy from dying stars into the production of new stars. Scientists had observed that SMGs do not leak gas like other galaxies. Narayanan’s model shows that the gas that would have leaked is actually recycled back into the galaxy. Gravity, due to the massiveness of the galaxy, is the cause of the gas reclamation and accrual. The galaxies are, in a way, self-sustaining. Because of their great mass, they also capture gas from nearby. In short, gas has a lot to do with why these galaxies are so intense.
Narayanan’s new model took the place of the former prevailing theory. Before this new model, scientists hypothesized that the SMGs were the product of multiple galaxies colliding. This new model does a better job of explaining the self-supporting process of gas recycling.
Another interesting thing about submillimeter galaxies is that they form stars at a much greater frequency than other galaxies. They produce about 1,000 new stars each year. In comparison, NASA reports that the Milky Way produces roughly seven new stars per year. This could be because SMGs are extremely energy efficient.
Submillimeter galaxies are also thought to be very old, formed when the universe was young. Further study of SMGs will surely reveal even more about our universe and the objects in it.