Variable Star Observing – Campaign Update

Update on the stars in the recent observing campaign

R Scuti (Download locator chart)

This RV Tauri variable (magnitude range 4.2 – 8.6) has now just come back into view in the dawn sky.   There have been two deep minima over the last 6 months, one around 3rd October 2008 and one around 22nd February 2009, with a shallow minimum occurring at some point when the star was too close to the sun for observation. A chart of my observations (yellow diamonds) against the worldwide observations is shown below. If anyone else has observations to add please let me know.

RZ Cassopeiae (Download locator chart):

I have not had any specific light curves from this star to report as yet. However as it is circumpolar it is still easily observable in the spring. It varies from magnitude 6.2 – 7.7 with the eclipse lasting almost 5 hours. The total period is 1.2 days, although the variation outside primary eclipse is very small. Key dates this spring to observe to catch eclipses are:

• The evenings of:
  • 21^st, 26^th March
  • 1^st, 7^th, 14^th, 20^th, 26^th April,
  • 2^nd, 8^th May
• Or the mornings of:
  • 20^th, 22^nd, 28^th March,
  • 3^rd, 9^th, 16^th, 22^nd, 28^th April,
  • 4th, 16th, 22nd, 28th May.

TX Draconis (Download locator chart)

Circumpolar semi-regular variable very close to Eta Draconis. The magnitude range is 6.6 – 8.4, and the average period is around 2 ½ months. Be careful you use the correct comparison stars. I have made a number of observations over the last few months and will try to provide a graph in the near future.

If you are interested in any stars in this campaign, please let me know so I can collate observations and we can put further results up on the website. Observations on U Orionis and Rho Cassiopeiae (which were observed at the recent observing evening) would also be welcome.