GCN Circular 29226

E. Troja (NASA/GSFC/UMCP), M. G. Bernardini (INAF-OAB),
C. Gronwall (PSU), A. Y. Lien (GSFC/UMBC), A. Melandri (INAF-OAB),
D. M. Palmer (LANL) and T. Sbarrato (INAF-OAB) report on behalf of the
Neil Gehrels Swift Observatory Team:

At 20:38:11 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 210102C (trigger=1015728).  Swift did not slew due to 
an observing constraint. 
The BAT on-board calculated location is 
RA, Dec 235.737, -37.222 which is 
   RA(J2000) = 15h 42m 57s
   Dec(J2000) = -37d 13' 19"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a double-peaked
structure with a duration of about 100 sec.  The peak count rate
was ~3000 counts/sec (15-350 keV), at ~65 sec after the trigger. 

Due to a Sun observing constraint, Swift cannot slew to the BAT
position until 15:14 UT on 2021 January 06. There will thus be no XRT
or UVOT data for this trigger before this time. 

Burst Advocate for this burst is E. Troja (eleonora.troja AT nasa.gov). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/)