Outburst of Comet 29P/Schwassmann-Wachmann
ATel #13110; Dennis Bodewits (Auburn U), Michael S. P. Kelley (U. Maryland), Quanzhi Ye (U. Maryland), on behalf of the Zwicky Transient Facility Collaboration
on 14 Sep 2019; 17:45 UT
Distributed as an Instant Email Notice Comets
Credential Certification: Dennis Bodewits (dennis@auburn.edu)
We report on a rapid increase in the brightness of comet 29P/Schwassmann-Wachmann from images acquired with the Zwicky Transient Facility (ZTF) operated on the 1.2-m Oschin Schmidt telescope at Palomar Observatory. The comet's brightness has been steadily decreasing since previously reported outburst that started around between 2019 Aug 1.50 and Aug 2.44 UT (ATel #12994) until it reached an apparent minimum around Aug 30 - Sep. 1 - 11 UT of r = 16.56 ± 0.04 within a circular aperture of 20,000 km at the position of the comet. A small outburst of 0.2 - 0.3 R-mag was first reported by Charles Bell (priv. comm.) on Sep 6.33 UT and is present in our observation acquired on Sep. 7.42 UT as a 0.12 ± 0.06 r-mag increase. The comet was back to its baseline activity on Sep. 11.42, but an i-mag of 15.82 ± 0.03 was measured on Sep. 12.40 UT, corresponding to an r-mag of 16.06 ± 0.4, indicating a rapid brightness increase of Δ r-mag = 0.49 ± 0.06. This event started between Sep. 11.42 and Sep. 12.40 UT. For the color correction, we assumed median comet color corrections from Solontoi et al. (2010) of g-r = 0.57 and r-i = 0.24.
| Date UT |
Mag |
Δ mag |
Band |
mag r |
Δ mag r |
| 2019 Sep. 12.40 |
15.82 |
0.03 |
i |
16.06 |
0.04 |
| 2019 Sep. 11.42 |
17.12 |
0.04 |
g |
16.55 |
0.05 |
| 2019 Sep. 7.42 |
16.20 |
0.03 |
i |
16.44 |
0.04 |
| 2019 Sep. 1.43 |
17.16 |
0.03 |
g |
16.59 |
0.04 |
| 2019 Aug. 31.45 |
17.12 |
0.03 |
g |
16.55 |
0.04 |
| 2019 Aug. 31.38 |
16.56 |
0.03 |
r |
16.56 |
0.04 |
| 2019 Aug 30.39 |
17.12 |
0.03 |
g |
16.55 |
0.04 |
Part of this work makes use of observations obtained with the Samuel Oschin Telescope 48-inch at the Palomar Observatory as part of the Zwicky Transient Facility project. ZTF is supported by the National Science Foundation under Grant No. AST-1440341 and a collaboration including Caltech, IPAC, the Weizmann Institute for Science, the Oskar Klein Center at Stockholm University, the University of Maryland, the University of Washington, Deutsches Elektronen-Synchrotron and Humboldt University, Los Alamos National Laboratories, the TANGO Consortium of Taiwan, the University of Wisconsin at Milwaukee, and Lawrence Berkeley National Laboratories. Operations are conducted by COO, IPAC, and UW.
