FRB20190417A-20230101-S001-R001-R-184849.fts
upper limit SN vs magnitude graph from USNO-B1 catalog
UT upper limit
2023-01-01 09:48:51.798
15.525 +/- 1.134 (3sigma)
14.945 +/- 1.136 (5sigma)
14.158 +/- 1.140 (10sigma)