AAVSO: American Association of Variable Star Observers

Proposal #225

Proposer (34732) Filipp Romanov (romanov_philipp@mail.ru) obscode: RFDA
Assigned To(3663) Dirk Terrell
Date SubmittedSept. 22, 2021

LL And in rare outburst now (about 14 mag). The amplitude of the superhumps is increasing: now it is about 0.25 mag. Time-resolved photometry (best with exposures of 60 seconds) for next weeks required: with V filter or unfiltered with a duration of 5 or more hours every night.

About the uniqueness of this system - from the paper "1993 Superoutburst of LL Andromedae" https://ui.adsabs.harvard.edu/abs/2004PASJ...56S.135K : "LL And may be an object filling the gap in the evolutionary track, which has recently been proposed to explain the unusual ultracompact binaries with an evolved mass donor".

I will upload the data to the AAVSO International Database and will send to VSNET (information is available there: "More continuous follow-up observations are needed to explore its nature!").

With best regards,


Target RA (H.HH) Dec (D.DD) Magnitude Telescope Observation Frequency Expiration Date Proprietary Term
LL AND 0.697631 26.62253 20.0–12.6 TMO61 daily March 23, 2022 No


(34732) Filipp Romanov — Sept. 22, 2021, 8:37 p.m.

There was some error in converting coordinates from J2000 to J2000d. Correct position: 00 41 51.47 +26 37 21.1 (10.46446 +26.62253) - from the VSX.

(4726) Kenneth Menzies — Sept. 24, 2021, 6:51 p.m.


Committed to large scope (TMO61). In SG filter at 60 second exposures for 6 hours. Tell me how it goes?


(34732) Filipp Romanov — Sept. 24, 2021, 7:07 p.m.

Thank you, Kenneth, these parameters should be fine.

Comments on this proposal are closed.