An Indiana University professor has embarked on a project to catalogue the properties of an astronomical number of galaxies.
For the next three years, professor Samir Salim will use a NASA grant to take existing data gathered from ground-based telescopes and orbital telescopes and compile data about how galaxies differ. For the data to be significant, Salim has to study many galaxies – approximately 11 million of them.
“Eleven million galaxies may sound like a lot, but it’s actually quite a lot,” Salim says. “So you can imagine just showing each galaxy on your screen for one second, okay, and then going to another one, another one, each second it’ll take you a full year of full-time clicking. It’s a huge number of galaxies.”
Salim says scientists primarily want to know how far away the galaxies are from Earth. From that data, he says, much more can be gleaned.
“You get the mass, you get the rate at which they form stars,” he says. “We can also get some additional information about how much dust these galaxies have, nd even, to some extent, what is their chemical composition. So all this together will give us a better understanding of how these galaxies change.”
Salim says researchers believe they know the distance to only about one million of the 11 million galaxies in the survey and plan to derive the distance to the other ten million as the database is completed.