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(Post Chat Update: The transcript has been posted...) Original announcement was:

Join us Sunday, October 25 at 7pm EDT (23UT) for an online chat with Brian Kloppenborg. Brian is Dr. Bob's graduate student at the University of Denver and a key advisor/scientist/everything-person for Citizen Sky. We'll talk about all aspects of CS so bring any questions you have. Just visit this web page to join us.

As always, the transcript will be posted online for those who cannot attend. Transcripts of other chats can be found here.Read more

In August 2009 Citizen Sky held a workshop in Chicago on epsilon Aurigae and observing.  Most of the talks during this workshop were videotaped.  The first set of videos are now online along with their corresponding presentation files.  If you missed the workshop or if you would like to revisit your favorite talk, check it out.  More videos are on the way, so stay tuned!

As noted by Jeff Hopkins in the Epsilon Aurigae Campaign newsletter and a recent Astronomer's Telegram, the eps Aur eclipse seems to have started later than was predicted by data from previous eclipses.  What could be the cause of such a change?  How could you confirm your theory? 

The scientific process often begins with a thorough discussion of the problem and brainstorming solutions with colleagues.  In an effort to start such dialog on Citizen Sky, I've started a forum to discuss the apparent shortening of the eclipse.  I'm sure with several people discussing the topic, we will be able to solve this mystery.Read more

As the light of the primary star continues to wane, discussions of the time of "first contact" have arisen - that's when the dark disk began to encroach on the F star photosphere.  Pre-eclipse predictions indicated the date could be JD 2,455,055 = 2009 Aug.11 (Hopkins & Stencel, 2008 Epsilon Aurigae - book - p.97).  Different observers point to slightly different times to represent the start of ingress. 

Jeff Hopkins (Hopkins Phoenix Observatory) has analyzed light curve data and concluded the eclipse began (V band) on JD 2,455,072 = Aug 28.
See his webpage at  http://www.hposoft.com/Plots09/FirstContact.JPG .

Italian observer, M.M.M.Santangelo (Osservatorio Astronomico di Capannori) has published statistical results of his independent photometry in issue 2224 of the Astronomer's Telegram and states that the eclipse "did not still take place until at least August 17th" = JD 2,455,060.  Read more

Citizen Sky now has a fan page on Facebook.  Check it out: www.facebook.com/CitizenSky

The first video from the Chicago Workshop has been posted to the forums. It's a talk about supergiant stars by Dr. Doug Welch. Consider this a sample of much more video coming soon.

Like the autumn leaves, light from epsilon Aurigae is dropping fast.  I've been using a simple digital camera and recorded a fade to V ~ 3.35 this weekend (10/3/09).  If you have been watching the show week to week, epsilon is clearly fainter than eta now, and on its way to being no brighter than zeta in a matter of week, if all keeps to schedule.

As Aurigae is rising by 10pm local time, you no longer need to catch it during pre-dawn hours to see the eclipse happening before your eyes.  Catch those clear, cool nights of autumn and enjoy the spectacle!Read more

I am happy to announce a new feature on the Citizen Sky website! 

Participants can now create and search event listings.  This feature can be found under the "Communicate" tab on the homepage.  Events can be searched for by date, country, state, or event title.  Feel free to use this feature to post any Citizen Sky or Astronomy related public events!Read more

Eclipse is underway (V = 3.23 on 9/25/09)and the debate over when First Contact really occurred has begun.  Initially, Jeff Hopkins figures it to be RJD 55072 (late Aug) while Richard Miles likes a date several days prior to that (mid-August).  Whether the final answer is JD 2,455,072 or a week earlier, in either event it appears to be at least one week after predicted start (55055, early August).  This arguably means further changes in eclipse shape and duration can be expected.  Read more

The third post in our series on light curve analysis looks at both recent data and data from previous eclipses to answer the age-old-question: Who shot JR?  Has the eclipse started in visual light?