Skip to main content
Testing. You are viewing the public testing version of GCN. For the production version, go to
New Announcement Feature, Code of Conduct, Circular Revisions. See news and announcements

GCN Circular 21583

LIGO/Virgo G298048: Additional Swope Observations of SSS17a
2017-08-19T01:54:36Z (7 years ago)
Ryan Foley at UCSC <>
C. D. Kilpatrick, D. A. Coulter, M. R. Siebert, R. J. Foley (UCSC), B. J. Shappee, M. R. Drout, J. S. Simon, A. L. Piro (Carnegie), A. Rest (STScI)

report on behalf of the One-Meter Two-Hemisphere (1M2H) collaboration:

We obtained imaging in B, V, and i bands of SSS17a (Coulter et al., LVC GCN 21529) on 2017 Aug 19 UT with the 1-m Swope telescope at Las Campanas Observatory.  We calibrated these data using approximately 90 B, V, and i' APASS standards in the same field as SSS17a and report the following preliminary photometry:

B = 18.8 mag +/- 0.1 mag
V = 18.1 mag +/- 0.1 mag
i = 17.4 mag +/- 0.1 mag

Additional photometry is being obtained and analyzed.
Looking for U.S. government information and services? Visit