Into the Obscure Universe

Not only is everything bigger in Texas, Texas astronomers set their sights on what’s massive.

Credit: Caitlin Casey

Monster Galaxies. UT Austin astronomer Caitlin Casey explores the most extreme galaxies known in the universe – galaxies creating new stars at rates hundreds of times the rate of our Milky Way in the far outposts of the universe. These mysterious hubs build most of the stars that currently exist in the universe today. 

Radio of Unusual Size. These extreme galaxies are as luminous as they are large, but astronomers have only learned about them recently because something pesky got in the way: space dust. The tiny, sooty molecules are more common in these ancient galaxies Casey studies, shrouding nearly all starlight from view. To study the monsters hidden behind dust, Casey uses cutting-edge new millimeter-wavelength radio technology at the Atacama Large Millimeter Array in Chile.

Hubble’s Huge Successor. Casey also is part of the team, led by fellow UT Austin astronomy professor Steve Finkelstein, to use NASA’s largest-ever space telescope, the James Webb, to understand how galaxies in the early universe form stars and evolve. Casey plans to analyze the chemical composition of these monster galaxies as far as 10 billion light-years away.

Giant on the Horizon. UT Austin is among a dozen founding partners working to build what will be the world’s biggest and most powerful space-observing marvel: the Giant Magellan Telescope. Currently, astronomers like Casey can use the world’s biggest optical telescopes to barely eke out the enshrouded starlight from monster galaxies. GMT, by contrast, will allow for viewing hundreds of galaxies simultaneously – and with much greater sensitivity. 

“Starlight is only the tip of the iceberg,” Casey said. “Now we’re beginning to see everything that comes before – the entire process that brings gas from the pristine primordial universe to the point of forming stars.”