AAVSO: American Association of Variable Star Observers

Proposal #147

Proposer (36239) Richard Roberts (richard.w.roberts@jci.com) obscode: RRIA
Assigned To(3663) Dirk Terrell
Date SubmittedAug. 22, 2020

I'm putting together a LPV section program to study V725 SGR. The star was originally classified as a Cepheid with a 12 day period; however, this star is undergoing rapid changes. In the middle of the 21st century, the period expanding to about 50 day and seems to be around 85 days now. Consistent photometry is sparse and although it is obvious that this star is changing, there isn't enough data to figure out what is going on or even what this star should be classified as. Different papers claim its still a Cepheid, others an RV Tau and others a SRd. VSX lists is an an Lb. It is not know whether this star is a K4 giant or a K4 super-giant. I want to conduct BVRI photometry over at least 2 years in order to help identify the proper classification for this star, determine the rate of its period change, and if its pulsating in one or more modes. I'm hoping for good enough results to publish in the JAAVSO.

Target RA (H.HH) Dec (D.DD) Magnitude Telescope Observation Frequency Expiration Date Proprietary Term
V725 SGR 18.199844 -36.11122 14.4–11.9 OC61 1 Sept. 1, 2023 No


(3663) Dirk Terrell — Aug. 26, 2020, 4:27 p.m.

Because of the field crowding, the TAC suggests that OC61 be used for now, and switch over to the southern BSM systems once they are updated.

(4726) Kenneth Menzies — Sept. 1, 2020, 8:11 p.m.

Plan created and submitted to OC61.

(36239) Richard Roberts — Sept. 25, 2020, 3:38 p.m.

I haven't seen any data come in yet. Is OC61 operational?

Comments on this proposal are closed.