Follow-up information and discussions on Sieber's suspected variable star in Lyr

(vsnet 679, T. Kato) Makoto Iida (VSOLJ) has pointed out some discordance between the reported position and a possible candidate in Vehrenberg's Atlas Stellarum.

   From his drawing:



   o        +

  (o stars in GSC)

The mark '+' represents the original reported position by Sieber. There are only faint stars here in DSS; no star is visible here according to Iida's examination of Vehrenberg's atlas. Instead there is another star (@) on Vehrenberg's, but not in GSC. Which position correctly corresponds to the reported object?

We are eager to see the original CCD image. Will it be possible to put it somewhere on the Web or make it available by anonymous ftp?

Taichi Kato

Sieber's object (Andersson)

(vsnet 680, K-G. Andersson)

Dear Sirs,

The object reported by Sieber is present on Vehrenberg Falkauer atlas, as an object of magnitud aprox, 13. This is the same object visible on DSS, reported by Brian Skiff.

                Pos: (2000.0) 19h 17m 4.5s +33d 3' 58"
                     (1950.0) 19h 15m 11.8s +32d 58' 31"

Regards: Karl-Gustav Andersson
Solna, SWEDEN.

lyra variable?

(vsnet 681, D. J. Sieber)

Concerning the star in Lyra I reported missing from the GSC on 7/5/96. I've had a chance to take additional ccd images with longer exposures on 7/6 and 7/7. The estimated magnitude appears to be closer to 11.7 and the position as reckoned with the MEGASTAR program is slightly different from first reported. 19h 17m 4.8s 33d 03m 28s. I apologize for any inconvenience this may have caused.

D.J. Sieber

Object in GSC

(vsnet 682, B. Skiff)

Sieber's new position corresponds exactly to one of the components of the bright double star clearly visible on the DSS image. It is listed in the GSC as a "nonstar" at position 19 17 04.5 +33 03 27, and probably represents the merged pair. The UJ1.0 disc shows the two components separately.

The main point is that this is quite bright (mag. 11-12) on the DSS, and I think Sieber was misled merely by it's omission from the MegaStar plot. There is otherwise no reason to think it's a large-amplitude variable.

\Brian Skiff (

Field check

(vsnet 683, R. J. Bouma)

Dear Sirs,

I've been able last night to have a good look at the region of Sieber's suspect. I agree with Mr. Iida that the star on the Vehrenberg Atlas Stellarum is not at the position indicated by Sieber, although I see it closer to the position of Sieber's object than is indicated on the sketch (vsnet 679). With regard to vsnet 680, I checked Vehrenberg's Falkauer Atlas, and both stars, Sieber's and the 13th magnitude star of Atlas Stellarum, are NOT visible here; not on my copy anyway.
My visual inspections of the field indicate that Sieber's suspect must have been fainter than magnitude 13.5 on July 6.998, and fainter than 14.0 on July 7.962.

Reinder Bouma

Reinder J. Bouma          email:
Bekemaheerd 77            phone: +31 (0)50-5418227
9737PR  Groningen
The Netherlands

Sieber's conclusion

(vsnet 684, D. Sieber)

The information you provided solved the puzzle! I want to thank you for your efforts. Using your data and examining the MEGASTAR program a little closer, the star in question at 19h 17m 4.47s 33d 03m 27.4s showed up as a blend. Both GSC stars you provided gave the same location. MEGASTAR says the blend magnitude is 10.8. I'll stick with my ccd image estimate of 11.7 however since the object in question is only slightly dimmer than GSC2657:2581 @ 11.4, and much brighter than GSC2657:2268 @ 12.8.
Your right about a heck of a field... Think I better get out of the milky way area. Too much traffic.

Don Sieber

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