AAVSO: American Association of Variable Star Observers

Proposal #271

Proposer (34230) Christopher Colvin (christopher.colvin.1992@gmail.com) obscode: CCHC
Assigned To(3663) Dirk Terrell
Date SubmittedJuly 1, 2022

Good morning, TAC.

I'm requesting time on either the BSM Hamren or BSM NM telescopes for a research project on PMS/YSO stars in the constellation Ophiuchus.
The four targets you see below are requested for the following reasons.

1. V0852 OPH: monitor for potential flares and any interactions that may occur with the CPD during that time.
2. V0853 OPH: monitor for any interaction between the CPD and star without any flare present.
3: V2058 OPH: monitor for rapid variations, search for irregularly dense areas, attempt to determine the radius of the CPD.
4: V2062 OPH: monitor for rapid variations, search for irregularly dense areas, attempt to determine the radius of the CPD.

Our plan is to attempt to find any periodicity of any abnormally dense areas of protoplanetary discs, and follow up with radio telescope observations at PARI, as well as spectroscopy with personal telescopes throughout this timeframe.

Ideally, we would be able to measure the radius of the CPD's, and attempt to measure the size of any abnormally dense areas around the stars allowing us to better understand the formation of potential planets and possibly even the demise of CPD's after flare events.

Additionally, since these targets haven't been observed for a great while (many years, or some even never by an AAVSO member). having this new data would be valuable to add to our database and further flesh out the data we have on these interesting targets.

I am requesting that each star be observed every two days using B, V, and I filters and receiving 3 images per target per observing night around 12:00am local time.
V0852 would benefit from image stacking due to the minimum magnitude of 16, and an unknown current brightness.

All of the research compiled from the AAVSONET telescopes, PARI's 12m telescope, and amateur owned telescopes for spectroscopy, will be reviewed, and findings put into a research paper with the ultimate intent to publish in the JAAVSO.

Thank you for your time and consideration.


Target RA (H.HH) Dec (D.DD) Magnitude Telescope Observation Frequency Expiration Date Proprietary Term
V0852 OPH 16.423333 -24.49528 16.0–13.6 BSM_Berry Jan. 19, 2023 No
V0853 OPH 16.479167 -24.47167 14.68–12.6 BSM_Berry Jan. 19, 2023 No
V2058 OPH 16.432222 -24.34639 14.52–13.6 BSM_Berry Jan. 19, 2023 No
V2062 OPH 16.525833 -24.46000 14.5–13.4 BSM_Berry Jan. 19, 2023 No


(3663) Dirk Terrell — July 4, 2022, 7:06 p.m.

The TAC is generally in favor of this proposal but would like some feedback. The main thing is how the requested observing frequency addresses the desire to have both flaring and longer-term periodicity covered. What sort of periodicities do you expect? Are the three images sets to be taken back-to-back?

(34230) Christopher Colvin — July 5, 2022, 7:25 p.m.

Hi Dirk.

Yes, the three images are intended to be taken back to back. The thought process behind this is to be able to stack (if needed) and average these out on a per night basis.
The intention on observing only every two nights will free up telescope time since there is no pre-determined period.
Expected periodicities could be anything from a couple of days, weeks, or even months depending on the size of the dust clouds and distance from the star.
I am open to suggestions from the TAC in order to best utilize telescope time, and for the goal that I have here to detect flares and any repeatable periodicities.

Thank you.

(3663) Dirk Terrell — July 15, 2022, 7:41 p.m.

You will probably have to combine these data with other survey data to pick out the periodicities you are talking about.

(4726) Kenneth Menzies — July 20, 2022, 6:03 p.m.


I sent you a proposal template to fill out. Please return to kenmenstar@gmail.com.


(4726) Kenneth Menzies — July 23, 2022, 10:39 p.m.

Allocated to Berry

Comments on this proposal are closed.