21 Dec 2018
Message from Santa: DR2 is on its way
"The heavy load made the sleigh a bit slow", we heard a spokesperson of the reindeers say. "The data were placed under a tree at NCI, but the scientists of Australia will have to wait a little before unwrapping them", the delivery crew added. "We were riding without seatbelts, which made the journey twice as fast", revealed an insider, who prefers to remain unnamed. "Just hours after the delivery the sleigh crashed, wiping all traces of the goodies it carried." After a pause he added, "a day earlier and we would have gone back to the North Pole to wrap it all up from scratch". According to an observer with intimate knowledge of the scene that would have moved the ETA to around Chinese New Year.
Rumours aside, Australian users will soon be able to access Data Release 2 from SkyMapper, the first release to include data from the deeper Main Survey. Data Release 2 includes 120,000 images observed over four years from March 2014. Over 500 million unique astrophysical objects are catalogued and cross-matched against Gaia DR2, 2MASS, AllWISE, GALEX, PS1 as well as against spectroscopic catalogues such as GALAH DR2.1, 2dFLenS, 6dFGS and 2QZ.
The gain in depth is most noticeable in the g and r bands, where the Shallow Survey exposures are only 5 sec long, compared to the Main Survey's 100 seconds. The following two g images of the edge of the galaxy M83 are from the Shallow and Main Survey respectively:
Data access services will be set up at NCI after the Christmas break to enable general access.