# C/2014 UN271 (Bernardinelli-Bernstein): The Nearly Spherical Cow of Comets

@article{Bernardinelli2021C2014U,
title={C/2014 UN271 (Bernardinelli-Bernstein): The Nearly Spherical Cow of Comets},
author={Pedro H. Bernardinelli and Gary M. Bernstein and Benjamin T. Montet and Robert J. Weryk and Richard J. Wainscoat and Michel Aguena and Sahar Allam and Felipe Andrade-Oliveira and James Annis and Santiago {\'A}vila and E. Bertin and D. Brooks and David L. Burke and A. Carnero Rosell and Matias Carrasco Kind and Jorge Carretero and R. Cawthon and C. J. Conselice and M. Costanzi and L. N. da Costa and M. E. S. Pereira and Juan Carlos de Vicente and H. Thomas Diehl and S. Everett and I. Ferrero and Brenna L. Flaugher and Joshua A. Frieman and Juan Garc'ia-Bellido and Enrique Gazta{\~n}aga and David W. Gerdes and Daniel Gruen and Robert A. Gruendl and Julia Gschwend and Gaston R. Guti{\'e}rrez and Samuel R. Hinton and Devon L. Hollowood and Klaus Honscheid and D. J. James and Kyler W. Kuehn and Nikolay Kuropatkin and Ofer Lahav and Marcio A. G. Maia and Jennifer L. Marshall and Felipe Menanteau and Ramon Miquel and R. Morgan and R. L. C. Ogando and Francisco Paz-Chinch{\'o}n and A. Pieres and Andr'es A. Plazas Malag'on and Mario Rodr{\'i}guez-Monroy and A. K. Romer and Aaron Roodman and E. Sanchez and Michael S. Schubnell and S. Serrano and Ignacio Sevilla-Noarbe and M. Smith and Marcelle Soares-Santos and Eric Suchyta and Mollye E. C. Swanson and Gregory G. Tarl{\'e} and C. To and Michael Troxel and T. N. Varga and A. R. Walker and Y. Zhang},
journal={The Astrophysical Journal Letters},
year={2021},
volume={921}
}
• P. Bernardinelli, +64 authors Y. Zhang
• Published 20 September 2021
• Physics
• The Astrophysical Journal Letters
Comet C/2014 UN271 (Bernardinelli-Bernstein), incoming from the Oort cloud, is remarkable in having the brightest (and presumably largest) nucleus of any well-measured comet and having been discovered at the heliocentric distance r h ≈ 29 au, farther than any Oort cloud comet. In this work, we describe the discovery process and observations and the properties that can be inferred from images recorded until the first reports of activity in 2021 June. The orbit has i = 95°, with a perihelion of… Expand

#### References

SHOWING 1-10 OF 58 REFERENCES
Pre-discovery Observations and Orbit of Comet C/2017 K2 (PANSTARRS)
• Physics
• 2017
We present a study of comet C/2017 K2 (PANSTARRS) using pre-discovery archival data taken from 2013 to 2017. Our measurements show that the comet has been marginally increasing in activity since atExpand
C/2010 U3 (Boattini): A Bizarre Comet Active at Record Heliocentric Distance
• Physics
• The Astronomical Journal
• 2019
We present a photometric and dynamical study of comet C/2010 U3 (Boattini), which was seen active in prediscovery data as early as 2005 November at a new inbound record heliocentric distance \$r_{\rmExpand
No Rotational Variability in C/2014 UN271 (Bernardinelli-Bernstein) at 23.8 au and 21.1 au as Seen by TESS
• Physics
• Research Notes of the AAS
• 2021
The recent discovery of a hundred-kilometer-scale comet, C/2014 UN271 (Bernardinelli-Bernstein), has provoked interest in the activity displayed by such a large body inbound from the Oort cloud. WeExpand
Dynamical evolution of C/2017 K2 PANSTARRS
• Physics
• Astronomy & Astrophysics
• 2018
Context. The comet C/2017 K2 PANSTARRS drew attention to its activity at the time of its discovery in May 2017 when it was about 16 au from the Sun. This Oort spike comet will approach its perihelionExpand
Origin and Evolution of Long-period Comets
• History, Physics
• The Astronomical Journal
• 2019
We develop an evolutionary model of the long-period comet (LPC) population, starting from their birthplace in a massive trans-Neptunian disk that was dispersed by migrating giant planets. Most cometsExpand
New stellar encounters discovered in the second Gaia data release
• Physics
• Astronomy & Astrophysics
• 2018
Passing stars may play an important role in the evolution of our solar system. We search for close stellar encounters to the Sun among all 7.2 million stars in Gaia DR2 that have six-dimensionalExpand
CO-driven Activity in Comet C/2017 K2 (PANSTARRS)
Comet C/2017 K2 (PANSTARRS) was discovered by the Pan-STARRS1 (PS1) Survey on 2017 May 21 at a distance 16.09 au from the Sun, the second most distant discovery of an active comet. Pre-discoveryExpand
Stellar Occultation by 2060 Chiron
Abstract A 14th magnitude double star was occulted by 2060 Chiron on 1993 November 7. Observations of this event were obtained from five locations in California. An occultation by Chiron's nucleusExpand
Distant Comet C/2017 K2 and the Cohesion Bottleneck
• Physics
• The Astronomical Journal
• 2019
Distant long-period comet C/2017 K2 has been outside the planetary region of the solar system for 3 Myr, negating the possibility that heat retained from the previous perihelion could be responsibleExpand
CO in distantly active comets
• Physics
• 2016
Activity of most comets near the Sun is dominated by sublimation of frozen water, the most abundant ice in comets. Some comets, however, are active well beyond the water-ice sublimation limit of ~3Expand