A photometric analog for ʻOumuamua in our solar system

One of the many peculiarities of the enigmatic interstellar object ʻOumuamua was its high-amplitude photometric variability, which had a range of nearly three magnitudes — implying that the first 'interstellar asteroid' had an extremely elongated shape. The near Earth asteroid 2016 AK193 is one of the few bodies in our solar system that shows photometric variations as large as those of ʻOumuamua. At absolute magnitude H=22.0, 2016 AK193 is also similar in size to ʻOumuamua. The asteroid could therefore be a helpful analog to ʻOumuamua within the solar system, offering insight on how objects with extreme shapes can form and survive. We present time-series photometry of 2016 AK193 from the discovery apparition in 2016 and from a more distant Earth encounter in early 2020. We discuss implications for the object’s shape and rotation state, as well as opportunities for further study.