AT2025acft microlensing events in Cygnus

[Lukasz Wyrzykowski]

Dear All,

There is a bright and potentially interesting microlensing event found in Cygnus constellation:

https://bh-tom2.astrolabs.pl/targets/AT2025acft/

My prediction is that it will peak within next month, at about 14 mag in red bands, so it should be easily accessible by most of the telescopes.

Very high cadence (at least couple of times a night, ideally every 1-10 minutes) observations within next 2-3 months in multiple bands (gri/BVRI, minimally in g+r+i or V+R+I), could reveal some potential planetary anomaly if we are lucky. Or help constrain the mass of the lens and identify a black hole if lensing. 

Please make sure you have good quality flatfield images applied to your data. Also, make sure the exposure time is long enough to obtain enough signal to noise for our target as well as stars within the field of view (ideally down to V~18 mag).

Please upload your observations to BHTOM as soon as possible so we can trace the evolution of the event and react quickly if there is an anomaly.

Clear skies!

Lukasz

on behalf of the BHTOM Team