A new Hubble survey of galaxies is the largest yet. It'll provide a huge list of targets for further observations by the James Webb.
A paper titled “3D-DASH: The Widest Near-Infrared Hubble Space Telescope Survey” presents the new mosaic. It’ll be published in The Astrophysical Journal and is currently available at the pre-press site arxiv.org. The lead author is Lamiya Mowla, Dunlap Fellow at the Faculty of Arts & Science’s Dunlap Institute for Astronomy & Astrophysics at the University of Toronto.
Survey size is critical in the study of galaxies. To be productive, surveys have to identify unique phenomena in the Universe: the most massive galaxies, the oldest galaxies, and galaxies on the verge of merging are critical to expanding our understanding of galaxies. So are highly active black holes. But to find those, astronomers need huge images that they can comb through.
DASH stands for Drift And SHift, the name of the new imaging technique that Mowla and her colleagues. DASH is similar to taking a panoramic image with a smartphone. The method captures multiple images that are then stitched together into one enormous image. DASH is a huge time-saver and took images in 250 hours that previously would’ve taken 2000 hours.