July 2009 Photometry of Epsilon Aurigae

It appears that through the end of July 2009 epsilon Aurigae is still very bright.

The following is from data submitted to the Campaign for July 2009.

Richard Miles

Golden Hill Observatory

Location:  Stourton Caundle, Dorset, England

Latitude/Longitude/Altitude (ASL):  West 2.405 deg, North 50.931 deg

Time Zone:  GMT = 0 hours

Telescope:  0.06-m Refractor (Takahashi FS60C)

Filter Set:  Johnson V,  Cousins Ic

Detector:  CCD Camera (Type:  Starlight Xpress SXV-H9)

      Date           JD       UT    V mag  SD     Ic   SD

01/02 June 2009 2,454,984.41 21:50  3.01  0.015

07/08 June 2009 2,454,990.42 22:11  2.991 0.006

23/24 June 2009 2,455,006.43 22:19  2.894 0.016

03/04 July 2009 2,455,016.46 23:03  2.854 0.036  2.21  0.05

15/16 July 2009 2,455,028.59 02.07  3.010 0.025  2.29  0.015

17/18 July 2009 2,455,030.58 01.54  3.034 0.015  2.324 0.018

19/20 July 2009 2,455,032.54 01.03  3.031 0.008  2.330 0.015

21/22 July 2009 2,455,034.54 00.52  3.076 0.031  2.323 0.025

22/23 July 2009 2,455,035.00 ?????  3.05  0.02   2.28  0.03

29/30 July 2009 2,455,042.55 01:00  3.016 0.012  2.355 0.011

Comments:  Mean, standard deviation of 4 determinations bracketed either

side in time by Lambda Aurigae.

Assumes V=4.71, Ic=3.99 for Lambda Aurigae

Each determination was an average of 50 frames.

Telescope was moved so that same area of CCD used to image both the variable

and comparison star.

Paul J. Beckmann: Jim Beckmann Observatory (JBO)

Mendota Heights, MN USA

Latitude/Longitude/Altitude (ASL):

     44°53’17.46” N     93°06’53.45” W     953 feet ASL

Time Zone: GMT -6 hours Telescope: 8” f/10 Meade 2080 optics

Optec SSP-3a Filter Set: Optec Johnson BVRI

  UT Date 2450000+   B     SD    V     SD     R    SD     I     SD

07/21/2009 5034.87 3.368 0.046 3.062 0.025  2.475 0.002 2.314 0.062

07/24/2009 5037.87 3.390 0.034 3.037 0.015  2.467 0.006 2.279 0.032

07/27/2009 5040.85 3.336 0.040 3.040 0.011  2.464 0.012 2.327 0.044

Stencel/Long, University of Denver, Denver, Colorado USA

DSLR V Band Data

  UT Date       2450000 +       V      SD

07 July 2009     5,019.92      3.01     ??

Des Loughney

Edinburg, Scotland, UK

Canon DSLR, 200 ISO, f4, 85 mm lens, Exposure 5 seconds

Eta Aurigae used as the comparison star at V = 3.18

Des uses a remote switch to activate the Canon 200 Digital Single Lens Reflex (DSLR) camera with 85 mm lens. He takes between 10 and 20 exposures stacks and processes them with AIP4WIN.

     JD

2,450,000 +     UT Date     UT       V Mag    

4,994     11 June 2009     23.50     2.56 (Very high air Mass)

5,022     10 July 2009     02.20     2.975 SD 0.002

5,023     11 July 2009     02:15     2.971 SD 0.012

5,031     19 July 2009     04.75     3.017 SD 0.005

5,032     20 July 2009     04.70     3.013 SD 0.008

5,033     21 July 2009     04.70     2.939 SD 0.005

5,034     22 July 2009     04.65     2.927 SD 0.008

5,035     23 July 2009     04.65     2.994 SD 0.012

5,036     24 July 2009     04.65     2.904 SD 0.008

5,037     25 July 2009     04.60     3.008 SD 0.015

5,038     26 July 2009     05.05     3.012 SD 0.007

5,039     27 July 2009     05.10     3.008 SD 0.005

5,040     28 July 2009     05.10     3.017 SD 0.008

5,041     29 July 2009     05.10     3.008 SD 0.007

5,042     30 July 2009     05.10     3.047 SD 0.007

5,043     31 July 2009     05.10     3.015 SD 0.011

Gerard Samolyk

Greenfield, Wisconsin, USA

Equipment, CCD Camera and Camera Lens, ST9XE + 50 mm lens

          2,450,000+

  UT Date         JD        V         SD        B        SD

26 July 2009     5038     2.980     0.009     3.567     0.011

27 July 2009     5039     2.955     0.013     3.560     0.015

28 July 2009     5040     2.973     0.018     3.566     0.014

29 July 2009     5041     2.976     0.009     3.566     0.013

31 July 2009     5043     2.985     0.015     3.562     0.010