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CCD Images - Session 305 (2008-09-25)

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Objects Session Notes
Bullet DY Per - RCB Variable Star
Bullet SS Cyg - Dwarf Nova
Bullet Astrometric & Photometric Monitoring
- SS Cyg (dwarf nova)
-
R CrB, RU Peg, DY Per (variables)

- SAO 70474 attempt failed (due to cloud)

- Short evening session (1.4 hrs), cut short by developing cloud.
- Ambient Temperature 11.5 degC .
- CCD operation of -15 degC 
(at 72% average cooling).  
- main objective of the session was  to acquire images of key selected stars for ongoing photometric and astrometric analysis. 
- a secondary objective, to test revised routine for automated guiding between frames, was not possible due to early termination of the session. 


Goto Notes from 2008-09-25

-

 


DY Per - RCB Variable Star

DY Per (Perseus) 
Images from the last three session (2008-09-21, 2008-09-22 & 2008-09-25) 
suggest that DY Per has begun a dimming event. 
At mag +11.8 (V), the star is around 0.4 mag dimmer than it was 15 days ago and around 
1.1 mag dimmer than it was 10 months ago.
(At this stage it is impossible to say whether the decline will be shallow or deep. 
 It may dim to mag +13/+14 or even as low as +15.5 !. 
 (See Graph of DY Per on AAVSO - last 2000 days )

On the other-hand it may simply return to its previous brightness at around mag +11.5)
(Progress will be tracked on DY Per section on Eruptive Variable Stars page)
Image
Follow-up - 2008-10-11
(showing that September decline was part of significant downward trend)
Image 

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SS Cyg - Dwarf Nova

SS Cyg (Cygnus) 
Images from session S305 (2008-09-25) show an unexpected brightening in SS Cyg.
The star normal enters a low 'normal' state for between 2 and 4 weeks before rising.
Today's measure +11.0 (V) is unusual given it had been recently dimming 
and had reached +11.85 (V) just 3 days ago.
 (See Graph of SS Cyg on AAVSO - last 60 days )

(Progress will be tracked on SS Cyg / Cataclysmic Variable Stars page)
Image
  
SS Cyg - Follow up (2008-10-11)
Image

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Astrometric and Photometric Monitoring

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This Web Page: CCD Images - Session 305  (2008-09-25)
Last Updated : 2015-05-16
Site Owner : David Richards
Home Page : David's Astronomy Web Site