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New variable stars or artefact?

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astroivan's picture
New variable stars or artefact?


While searching for new objects in ZTF, I noticed an "extra" star on the preliminary map from the 2MASS overview. Approximate brightness is 11 R. The first thing I looked at was in MPChecker - there were no asteroidas at this point of the sky on February 10, 1999. Subject coordinates: RA(2000)=05:00:40.5 DEC(2000)=+75:30:03.3 (constellation of Giraffe). There is no DSS object on Palomar plates. It also doesn't exist on all images of ZTF object. In ASAS-SN data there is only one observation on April 14, 2016 with V=14.34. In VSX the object is also absent. On the PS1 images I was sure I couldn't find anything suitable. So maybe it is a star-like artifact? And who worked with 2MASS images and are they even publicly available? At 6.5" of the specified coordinates there is a star URAT1 828-037677 with fmag about 15 magnitude. But this object is not shown by Aladin (red cross on the map).

All the best, I.Sergey

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