Small Apparent Outburst of Comet 7P/Pons-Winnecke
Kritti Sharma (IITB), Michael S. P. Kelley (U. Maryland), Jigmat Stanzin (IAO), Harsh Kumar (IITB), Varun Bhalerao (IITB), G. C. Anupama (IIA), Sudhanshu Barway (IIA) on behalf of the GROWTH India Collaboration and Zwicky Transient Facility Collaboration
We report the discovery of an outburst of comet 7P/Pons-Winnecke in GROWTH India Telescope (GIT) data. The nightly averaged photometry is measured with a 22" radius aperture. The magnitudes are calibrated against PanSTARRS PS1 data release (Flewelling et al., 2018). On 2021 June 6.842 UTC, the comet had an apparent brightness of r = 13.48 +/- 0.06 mag. By our next epoch on 2021 June 7.858 UTC, the comet had brightened to r = 13.19 +/- 0.03 mag, suggesting an outburst strength of -0.29 +/- 0.07 mag. During the second epoch, the comet was at 1.24 AU from the Sun, and 0.44 AU from the Earth. The event was confirmed in Zwicky Transient Facility (ZTF; Bellm et al. 2019, PASP, 131, a8002) data, where the comet had an apparent brightness g = 13.68 +/- 0.03 mag on 2021 June 8.439 UTC. The g-r color of the comet is 0.34 mag, as measured from ZTF data on 2021 June 4.

The GROWTH India Telescope (GIT) is a 70-cm telescope with a 0.7 degree field of view, set up by the Indian Institute of Astrophysics and the Indian Institute of Technology Bombay with support from the Indo-US Science and Technology Forum (IUSSTF) and the Science and Engineering Research Board (SERB) of the Department of Science and Technology (DST), Government of India (https://sites.google.com/view/growthindia/). It is located at the Indian Astronomical Observatory (Hanle), operated by the Indian Institute of Astrophysics (IIA).

Based on observations obtained with the Samuel Oschin Telescope 48-inch Telescope at the Palomar Observatory as part of the Zwicky Transient Facility project. ZTF is supported by the National Science Foundation under Grant No. AST-2034437 and a collaboration including Caltech, IPAC, Weizmann Institute for Science, Oskar Klein Center at Stockholm University, University of Maryland, Deutsches Elektronen-Synchrotron and Humboldt University, TANGO Consortium of Taiwan, University of Wisconsin at Milwaukee, Trinity College Dublin, Lawrence Livermore National Laboratories, and IN2P3, France. Operations are conducted by COO, IPAC, and UW.
optical,comet,the sun,transient