The Minor Planet Electronic Circulars (MPECs) for July 15 through July 18 reported an unusually high number of re-observations of known trans-Neptunian objects (TNOs). These were found in the Pan-STARRS archive; most had not otherwise been observed since discovery. Is this activity part of the search for Planet 9, another observing program such as OSSOS, a result of software improvements, or just someone clearing a backlog?


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This is the result of a new way to investigate the images taken by the PanSTARRS survey, see Weryk et al. 2016.

A second batch of new discoveries was issued on July 26. This has been planned for several years, and now there's enough data to get useful results.

Note that Gareth Williams from the MPC has currently some technical problems with the most recent MPECs (O360 and higher). If these links don't work for you, it's probably because of that.

For further information, see the PS1 Science Consortium blog and Holman et al. 2015.


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