• DOI:10.1093/mnrasl/sly156
• Corpus ID: 119226483

Unusual polarimetric properties of (101955) Bennu: similarities with F-class asteroids and cometary bodies

@article{Cellino2018UnusualPP,
  title={Unusual polarimetric properties of (101955) Bennu: similarities with F-class asteroids and cometary bodies},
  author={A Cellino and Stefano Bagnulo and Irina Belskaya and Apostolos A. Christou},
  journal={Monthly Notices of the Royal Astronomical Society: Letters},
  year={2018}
}

• A. Cellino, S. Bagnulo, +1 author A. Christou
• Published 23 August 2018
• Physics, Geology
• Monthly Notices of the Royal Astronomical Society: Letters

We have obtained polarimetric measurements of asteroid (101955) Bennu, a presumably primitive near-Earth object (NEO) that is the target of NASA's sample return mission OSIRIS-REx. During our observing campaign, Bennu was visible from Earth under a wide range of illumination conditions, with phase-angle in the range 16 to 57 degrees. Together with (3200) Phaethon and (152679) 1998 KU2, observed very recently, Bennu is the only existing example of a primitive NEO observed in polarimetric mode over a wide interval of phase angles. Based on our polarimetric data, we propose that Bennu belongs to the unusual F taxonomic class defined in the 80s. According to previous works, the F-class includes objects with cometary features. This fact can be of great importance for the interpretation of the results of the exploration of this object by OSIRIS-REx. From polarimetry we also derive an estimate of the geometric albedo of Bennu: 0.059 +/- 0.003.