Multiple Outbursts of Interstellar Comet 2I/Borisov
ATel #13549; Michal Drahus and Piotr Guzik (Astronomical Observatory, Jagiellonian University in Krakow), and Andrzej Udalski, Milena Ratajczak, Krzysztof Rybicki, Patryk Iwanek, Marcin Wrona, Pawel Pietrukowicz, Igor Soszynski, Krzysztof Ulaczyk, Radoslaw Poleski, Przemek Mroz, Michal Szymanski, Jan Skowron, Mariusz Gromadzki, Dorota Skowron, Szymon Kozlowski (The OGLE Collaboration - Astronomical Observatory, University of Warsaw)
on 12 Mar 2020; 14:49 UT
Distributed as an Instant Email Notice Comets
Credential Certification: Michal Drahus (drahus@oa.uj.edu.pl)
We report the detection of two consecutive outbursts of interstellar comet 2I/Borisov in I-band images taken with the Optical Gravitational Lensing Experiment (OGLE) 1.3-m telescope in Las Campanas. The comet brightened by about 0.3 mag between UT 2020 March 4.3 and 5.3, followed by an approximately constant brightness between UT 2020 March 5.3 and 8.3. Another brightening, by about 0.4 mag, occurred between UT 2020 March 8.3 and 9.3, and was again followed by an approximately constant brightness between UT 2020 March 9.3 and 12.3. The total brightness increase is thus about 0.7 mag in 5 days between UT 2020 March 4.3 and 9.3. This behavior is strongly indicative of an ongoing nucleus fragmentation. The discovery was made as part of an intensive monitoring campaign by the OGLE Project, initiated in mid-December 2019.
M.D. and P.G. are grateful for support from the National Science Centre of Poland through SONATA BIS grant 2016/22/E/ST9/00109 and Polish Ministry of Science and Higher Education grant DIR/WK/2018/12. The OGLE project has received funding from the National Science Centre, Poland, grant MAESTRO 2014/14/A/ST9/00121 to A.U.
