Using ALMA, Ellis’ team will study these galaxies for dust, an indicator of how early heavy elements began appearing. “This will capture most of the stuff that Hubble cannot see,” says Dunlop. “If you want to make a complete census of cosmic star formation history, you’ve got to measure the un-obscured stuff that you see with Hubble, and the obscured stuff.”
For seeing the obscured stuff, nothing beats ALMA.
Bruce Lieberman is a freelance science writer in Carlsbad, California.