December 20, 2019
Dirk Schultze-Makuch
Air&Space Magazine

Headline image caption: ‘Where’d it go? An image taken in the 1950s (left) shows a large object at center that doesn’t appear in an image of the same field taken more recently. (Villarroel et al.)’

Physics in Sweden and the Institute for Astrophysics on the Canary Islands reports something strange in the current issue of The Astronomical Journal. They compared star maps from the 1950s with recent surveys, and discovered that 100 previously catalogued stars cannot be found anymore.

The group’s project, called Vanishing and Appearing Sources during a Century of Observations (VASCO) has been comparing mapped stars listed in the U.S. Naval Observatory Catalogue (USNO) B 1.0, dating from the 1950s, with those in another, more recent sky catalog, the Pan-STARRS Data Release (DR1). A total of 150,000 objects were found in the older catalogue (which lists 600 million stars) that did not have a readily identifiable counterpart in the new star survey, even though the Pan-STARRS Data Release includes stars that are five times less bright than the faintest light sources included in USNO. Of these 150,000 anomalies, the authors visually inspected 24,000 candidates and discovered that 100 of these point sources of light appear only in the older star survey. And since then, apparently, they’ve vanished.

SNIP