A preprint of the paper to be published in The Astrophysical Journal is available on arXiv.

"Since its launch more than 30 years ago, the Hubble Space Telescope has led a renaissance in the study of how galaxies have changed in the last 10-billion years of the universe," says Lamiya Mowla, Dunlap Fellow at the Faculty of Arts & Science's Dunlap Institute for Astronomy & Astrophysics at the University of Toronto and lead author of the study. "The 3D-DASH program extends Hubble's legacy in wide-area imaging so we can begin to unravel the mysteries of the galaxies beyond our own."

For the first time, 3D-DASH provides researchers with a complete near-infrared survey of the entire COSMOS field, one of the richest data fields for extragalactic studies beyond the Milky Way. As the longest and reddest wavelength observed with Hubble—just past what is visible to the human eye—near-infrared means astronomers are better able to see the earliest galaxies that are the farthest away.

Astronomers also need to search a vast area of the sky to find rare objects in the universe. Until now, such a large image was only available from the ground and suffered from poor resolution, which limited what could be observed. 3D-DASH will help to identify unique phenomena like the universe's most massive galaxies, highly active black holes, and galaxies on the brink of colliding and merging into one.