Struve 131 in M103

[wxsatuser]

Looking at some of my test shots with the Canon 60Da, before it died, I came across M103.

In M103 there is a multiple star Struve 131, not part of M103, but easily split with my set-up.

In the Cambridge DS Atlas it is shown as a double but looking around the net it seems it's a triple???

Anyway here is a short 30second exposure at ISO 800 thru my SW 80ED Pro+reducer+Hutech LP filter.

Not much if any colour, the primary is mag 7.2, the two companions are around mag 10.9.

AB pair  are 13.8” apart and AC pair are 28.2” apart.

Two images one with 131 ringed and one without.

[nightfisher]

nice image

[lunator]

Good pic

In my observation I found the primary white and the secondary yellow.

Cheers

Ian

[wxsatuser]

Thanks for that Ian, next time I get a chance will have a better look.

[huesmapl]

Mike,

A bit of a late response.

Thanks for listing those pics. I had actually observed M103 the night before with my 102mm refractor so I was looking with Google for other observations to make sure I identified Struve 131 correctly. The CDTA does list this as a double star at 7.3 and 9.9 magnitude and 14 arc sec separation. When I saw your post I was puzzled so waitied for the next good night and tried again. Again visually I could not see the third star as in your photo. So I switched to my C8 and could then faintly make out the third star. A few nights later I tried with my C9.25 and it was more obvious. With averted vision it started to pop out like in your photo. I guess this indicates the visibility limitations in my sky here south of Philadelphia.

Is that third star an actual companion? May be those making the CDSA had the same magnitude limitations ... hard to believe.

Thanks for posting that photo Mike.

Pete

[huesmapl]

My Skytools 3 software lists it as a triple with the C component separation as 28.2 arc sec and magnitude 11.59. The software only indicates easy detectability for my C8 and greater aperture. I should make better use of that software.

Here is a simple sketch (reverse image since I was using a diagonal). I am just starting out sketching so please for give some mis-alignments and lack of directional information.

[wxsatuser]

Hi Pete.

This triple seems a mystery, it's definately a double but I question the triple.

Open to any suggestions.

I'm currently going through SIMBAD to pinpoint the three stars.

[wxsatuser]

Running through SIMBAD and using the Aladin app these appear to be the three stars.

WDS J01332+6041A

WDS J01332+6041B

WDS J01332+6041C

B and C in SIMBAD definately come up as STF 131B and STF 131C respectively.

extract from WDS

                                                                                              Magnitudes

01332+6041STF 131AB    1827 2010   29 143 144  13.8  14.0  7.30  9.90 B5Iab     -001-001 -002-001 +59  271 N D  013314.01+604111.201332+6041STF 131AC    1901 2007   11 146 145  28.7  28.0  7.30 11.80           -001-001                   N    013314.01+604111.201332+6041STF 131BC    1901 2007   11 143 148  14.8  14.2  9.90 11.80           -002-001                   N    013315.15+604100.1

[huesmapl]

MIke, (Sorry for the late follow-up again)

Thanks for that data and the original photos that made me look closer!

full moon is coming on as well as the Holidays ... hope to get out again and make a better sketch in a couple weeks.

Regards,

Pete

[wxsatuser]

No problem.

Look forward to future sketches.