Research Byte

Published in the RSAA Lunations
Vol1 Issue2 1–31 March 2020

In February, the SkyMapper Team released the third data release of its Southern Survey. Initiated in 2002 by a team around Brian Schmidt, the SkyMapper telescope started its eponymous survey of the whole Southern sky in March 2014. Nearly six years later the current team released its largest and deepest data set yet. Three quarters of the Southern Hemisphere has deep data in all of the surveys' six spectral passbands. About 200,000 on-sky images of 268 Megapixels each have been processed and calibrated in this effort.

DR3 supports several science efforts at RSAA including the search for the rarest objects in our Universe: rare extremely metal-poor stars, rare changing-look AGN, and rare bright quasars in the early Universe. Only three weeks after the release, spectroscopic follow-up at the ANU 2.3m telescope confirmed the most distant bright quasar yet found by an Australian team, at redshift 5.41 and seen in an epoch when the Universe was just one billion years old. While the quasar team will keep pushing the frontier, the SkyMapper survey is used more and more by teams outside ANU. E.g., it provides the optical counterpart for the ASKAP radio surveys that have now commenced. The survey is scheduled to be complete in late 2021, and after a thorough quality review a final data release is planned for 2022.

Chris Onken and Christian Wolf, on behalf of the SkyMapper Team