TITLE:   GCN CIRCULAR
NUMBER:  21791
SUBJECT: Swift Trigger 770431 (GRB 170902A) is a not a GRB
DATE:    17/09/03 04:23:55 GMT
FROM:    Jamie A. Kennea at PSU/Swift-XRT  <kennea@swift.psu.edu>

J. A. Kennea (PSU) and C. B. Markwardt (NASA/GSFC) report on behalf of the
Swift team:

Swift trigger 770431 (AKA GRB 170902A) is not a GRB, but a Galactic
Transient. The source was detected almost 4 hours after BAT triggered by
MAXI (Negoro et al. ATEL #10699) and the Swift X-ray light-curve measured
after the BAT trigger shows no evidence of fading (Kennea et al., ATEL
#10700). Therefore we conclude that this trigger is in fact from a new
Galactic Transient named MAXI J1535-571.