Incoming! Here's a stack of 10 1-minute V-band exposures done tonight from our campus observatory, with the telescope tracking open-loop on the expected motion of the asteroid (about 0.8 arcsecond/second at this point). It was still too faint to show up in trailed images (compared to Landolt standard stars, I make it about V=14.8 in these images, a sequence finishing about 0130 UT on 28 January). Just where the JPL Horizons ephemeris predicted; using a set of elements from the Minor Planet Center and Guide8 was noticeably worse, and I don't know if that's a time-of-update issue or accuracy or propagating such a nearby object. We figured it was best to do this tonight - the weather forecast suggests only a short clear window after sunset tomorrow if at all. We found out that it's still too faint to get video, since in cold weather the air-handling system shakes the whole building at frequencies that make for the most interesting star images when beating against a 30 Hz frame rate.
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