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Under Observered Variables

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PKV's picture
Under Observered Variables

I frequent the AAVSO and the Yahoo VSObs-Share web sites often, noting potential objects for observation.  Gary Poyner recently posted a visual observation for V532 OPH, a recently discovered RCB star.  I was amazed only to see 13 observations for V532 OPH in the AID over the last 365 days.  What are some other "under observed" variables?  Many can be found in the LPV Circular or Tom Bretl's AAVSO LPV Bulletin.exe program.  Here are some of my candidates for "under observed" variables:  RR VIR with 44 observations over the last 365 days with mostly CCD observations by SXN and PKV, T OPH with 34 observations over the last 365 days, U CAP with 29 observations over the last 365 days and X CAP with 15 observations over the last 365 days.  All of the above are now in my visual and CCD monitoring programs.  Many other variables of all types may be "under observed."  Most of the YSO's come to mind.  Many "legacy" LPV's are also under observed.  Does anyone else have specific variable stars that are "under observed" that require additional attention?  Kevin - PKV

paw's picture
under observed

I'll take up V532 Oph visually - I visit nearby fields every clear night!

As for a list of others, I'm in the south. Almost everything's under observed.


FRF's picture
Matthew Templeton is his

Matthew Templeton is his recent article Amateur Observing Patterns and Their Potential Impact on Variable Star Science analyzing the observations in the AID comes to the conclusion that

"Two trends are evident: the decreasing number of days per year when individual stars are observed, and the overall decreasing number of visual observations submitted. The former is shown through an analysis of data submitted for a number of subclasses of cataclysmic variable, while the latter is generally evident across all variable star types through our overall annual totals.
A decrease in nightly coverage may impact the kinds of science that can be done with AAVSO light curves. The decrease in visual observing may result in a loss of long-term coverage that impacts the usability of long-term light curves."

According to him both in the case of legacy LPV and legacy CVs - an in general almost all variables have lower  daily coverage. Indeed, looking at the AAVSO Bulletin #75 the numbers tell clearly that most of the LPVs are underobserved. But as John Bortle has just pointed to it, even well known circumpolar CVs, like UV Per are underobserved between April and June when they are low on the sky.

Looking at the number of observations in the AAVSO International Database during calendar year 2011 even W Cet, SV And, Y And, Z Cet, U Cet, R Psc, W Aur, Z Tau, RU Tau, V Cam, T CMi, T Hya, T Vir, RS Lib, T Oph, S Oph, T Ser, RZ Her, W Aql, S Sgr, X Aql, RR Aql, Y Aqr, R Lac, S Aqr, V Cet can be listed as underobserved - just to name a few.

FRF's picture
time to start a project "Adopt an LPV!" ?

I've already told to Mike Simonsen and some Hungarian observers, but it seems there is a time to start a project can be called "Adopt an LPV!".

The idea can be that we try to recruit at least 3-5 (ideally at least 10) observers for each legacy LPVs, but at the beginning at least for the "endangered ones", that are especially underobserved. The people who adopt an LPV undertakes that each week (or at least twice a month) possible makes and effort to observes his/her adobted LPV. Especially on the morning sky. Even CCD observers who usually take time series for one or two single objects for a whole night can be recruited to adopt one or two LPVs. If we start to promote and implement this project we can maybe secure a better foverage for underobserved LPVs.

I've told this idea to a Hungarian girl who observes mostly meteors, even she liked the idea an promised to observe R Leo regularly. (Well, you can say R Leo isn't underobserved at al, but this project can be exciting even for for a beginner, who never observed variable stars yet.) 

In the era of "Web2.0" this kinf of projects can be easily implemented. I've alreadycreated an Adopt an LPV! spreadsheet for this project some month ago, where observers themselves can write their namecodes for the appropriate stars they adopt within the framework of this project

What do you think? Shall we proceed with this kind of project?

Of course we can start an Adopt a CV! project for underobserved CVs too, but it would be harder to implement, since the goal in this case would be the need to manage at least daily coverage for the specific CVs. But at least we can start with LPVs where at at least a weekly coverage is achievable...

SET's picture


I have bookmarked the website for your spread sheet. This is a great idea. Please put my initials

SET next to the following 8 stars:

R And, R Ari, R Aur, R Boo, V Boo, S Cet, S CrB, and R Tri.

I will try to get out and observe them as much as possible.

Thanks for doing this.

Chris Stephan   SET

Robertr Clyde Observatory

Sebring, Florida  USA

FJQ's picture

I'll take on TU And & khi (Chi) Cyg. 

James Foster Los Angeles, CA - FJQ

pox's picture
Good idea! I've always had a

Good idea! I've always had a soft spot for Miras. Many of the stars in the list are bright (as in binocular) objects, aren't they? I already observe R Cam and TZ Cyg but will add SV And, T Ser (near that brilliant cluster whose name escapes me) and W Per (near EO Per).

FRF's picture
Mike (POX) do you mean you

Mike (POX) do you mean you adopt R Cam, TZ Cyg, T Ser, SV And and W Per? Shall I put your name to these stars in the spreadsheet?

potterrb's picture
I'm adopting

Robert, I like your "adopt an LPV" effort!  I checked your spreadsheet, and I already have 46 of the stars in your spreadsheet on my regular observing program.  But I should probably not take on too many here, so for now sign me up for the following:

  • R Cas
  • T Cas
  • W Cas
  • WZ Cas
  • AF Cyg
  • U Cyg
  • CH Cyg
  • g Her
  • W Lyr
  • RY Dra

I also like to work the variables in UMa, when they're not too low on my obstructed horizon.  I use Canon 15x50 binoculars and a 200mm f4 reflector.

One other good source of targets is the AAVSO website's Basic Observation Planner.  It tends to recommend under-observed variables, I use it to generate my list of LPV/SRB targets.

pox's picture
Yes, please do. By the way,

Yes, please do.

By the way, not one usable clear night in the whole of July!

ret45's picture

Hi Robert,

I'm a newbie, since I started watching my first LPV in January and this is my first post here.

From your spreadsheet, I selected the following stars because I already did some estimations and know I can afford with my actual instruments:

Alf Ori, Eta Gem - eyes only required - from 10-stars citizen sky beginners program.

Alf Her - eyes only required, I'm doing on it some tests with my DLSR to learn taking good pictures for photometry purposes (BTW I'll have questions about these tests, I'll post later in photometry forum)


R Leo - X Oph - U Ori - SS Vir

as the seasons go on, I could add some others yet.



douglasfowler's picture

Dear Robert,

I think your idea is a good one and I have also bookmarked your spreadsheet.

I had been looking around for a few under-observed myself (as I now see from the comments that others have done this as well). I like the lists that SET and potterrb have listed in their comments. These are many of the same stars that I have been watching as well. If I am not horning in or crowding either of them, I would also like to adopt the following stars to start with (they have become some of my favorites):

R Tri, AF Cyg, GH Cyg, and g Her

Thanks. My intials are FDU

Best wishes, 

Doug Fowler, FDU


FRF's picture
re: Adoption

Hi Doug,

"R Tri, AF Cyg, GH Cyg, and g Her"

I assume you wanted to write CH Cyg. (GH Cyg is a cepheid, not an LPV, not even a symbiotic star with LPV component.)

Anyway, I'll mark your adoption in the spreadsheet "Adopt an LPV!".

Clear skies,

Robert Fidrich (FRF)

douglasfowler's picture
CH Cyg


Yes, thank you! I did mean CH Cyg.

Doug Fowler, FDU

FJQ's picture
khi Cyg & TU And Observations so far.....

To:  Robert,

Here is what I've observed, reduced & submitted to AASVO for these 2 adopted LPVs.  James Foster-FJQ, Los Angeles, CA                                                

FRF's picture
Filling the spreadsheet

I'm really happy to get so fast responses from you! Although the spreadsheet is still under construction, and conntains only 50 LPVs yet, already 21 out of them has been adopted by at least one observer.

I can also put myself to the list of adopters of khi Cyg since I regularly make DSLR images of the field with an 300mm focus (zoom) objective (EY Cyg, TT Cyg and V482 Cyg is also visible on my images) and of course sometimes I observe khi Cyg with my 20x60B too.

Later on I'll include more LPVs into the spreadsheet. And of course I can share the spreadsheet with anyone who has gmail account, and you can also edit the spreadsheet if you want (you can write your AAVSO code into the field of your pet LPV etc.)

Maybe we sometimes can discuss on #aavso IRC channel how to promote this project and invole as many AAVSO observers as possible, in order to achieve that all Legacy LPVs be adopted by 3-5(8) observers who make weekly (or at least 2x a month) observations of these stars (especially on the morning sky).

But if you don't officially 'adopt' and LPVs, just observe her regularly without any obligations, that is fine too. The main target is to increase the coverage at least of the Legacy LPVs. But in the long run, when we'll reach the stage that at least several of the target start have been adopted by a couple of observers they can also start the communication among eachother and tell the others when they cannot observe the specific star because of bad wheather or being too faint for his/her equipment etc.

FRF's picture
Legacy LPVs in the "Adopt an LPV!" spreadsheet

I started to include and highlight (with oranges background color) the Legacy LPVs in the spreadsheet. Looking at the Bulletin it seems that most of the Legacy LPVs are quite well covered, but the rest of the AAVSO LPV Program stars are quite poorly observed. So we need to keep the Legacy LPVs observed and put more emphasyze on the underobserved LPV Program stars.

PYG's picture
Re: Under observed variables

It was actually a V-band observation of V532 Oph obtained with the BRT. At -21 degrees declination, this field is impossible for me to observe due to the bright orange glow of Birmingham just a few miles South of me. Just to throw an interesting star into the hat, V1117 Her ( NSV 7883 a Herbig Ae/Be star) is currently very faint (152 two nights ago). This is a very underobserved star. Perhaps I have the only data in AID? Anyway these objects are fascinating to watch from night to night, and V1117 Her definitely deserves further attention. Not too far from the wonderful Mira star SS Her. An easy step from one to the other.

Gary (PYG)

FRF's picture
V1117 Her + SS Her and UV Her

Thanks Gary, V1117 Her seems to be an interesting YSO. And she lies half was between SS Her and UV Her / AS Her, so nice target for LPV fans too.

SYO's picture
V1117 Her & T Ser

 V1117 Her looks interesting, think I'm going to add it to my program.

T Ser is a Mira I've observed in the past at min. Seems like it's always a bit under observed. Funny, because it's in a nice star field near the open cluster NGC 6633. I mean to have another look at this star soon. Looks like it's at  11.7 as of 6/22. Cheers.  

Aldebaran's picture
Great idea! You can count me

Great idea! You can count me in! I would like to adopt following stars: V Cam, SV And and R Lyn. It's still summer with light nights here in Finland, but I'll start observing these stars as soon as it gets dark again!

-Juha Ojanperä

GTN's picture
V532 Oph very active

The RCB star V532 Oph practically exploded from 12.3 to 11.4 in a bit over 1 day on 7/16-18.

Looks like it wants watching as often as possible.  It has been very active this season.  (Time series might even show some interesting stuff going on.)   The maximum magnitude has been on the rise, too.  A very active phase may last only a short time - or not.  I've "adopted" V532 Ophf for my RCB program.  I'm concentrating on the most southern of the RCBs visible from Tucson.

Sebastian, as you add new RCB stars, would it be possible to give a bit  of priority to variables between, say +25 and -25 in Dec?  Except for the light dome over Tucson in the SE, I can get fairly decent coverage down to -25 deg, but the data will have a very strong spike at 1 day in the frequency spectrum at that Dec!



FRF's picture
your adopted LPVs

Dear Mike (POX), Juha, Richard and Giusepe,

Sorry for not replying earlier, but I was on holydays, my rocksack (with my netbook etc. in it) has been lost, but finally I had some time and updated the spreadsheet. You  and your adopted stars are now marked in the spreadsheet.

Maybe a new topic (let say in the Campaigns forum pages?) would be beter to start, especially since some of the Legacy LPVs are not really underobserved... Or just continue here? What do you think?

Clear skies,

Robert Fidrich (FRF)

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