International
Epsilon Aurigae Campaign 2009


This web site was created by Jeffrey L. Hopkins and Dr. Robert E. Stencel in May of 2006. It is acting as the International Epsilon Aurigae Campaign Web site for the 2009 - 2011 eclipse of the star system. The periodic Campaign Newsletters are edited by Jeffrey Hopkins with Dr. Robert Stencel and Robin Leadbeater as Coeditors. The site is hosted and maintained by the Hopkins Phoenix Observatory.

 

Epsilon Aurigae Star System

The epsilon Aurigae system is among the most interesting eclipsing star systems. It has puzzled astronomers for nearly 200 years. It is a bright star (3rd magnitude) located about 3 degrees southwest of Capella and eclipses once every 27.1 years. It is at the vertex of a triangular group of stars known as "The Kids". Zeta Aurigae, another interesting long-period eclipsing binary, makes up one of the other two stars.

What makes this star system so intriguing is not just its long period but the length of its eclipse, what happens during the eclipse and what happens out-of-eclipse. The eclipse lasts nearly two years which with the 27.1 year period means the eclipsing body must be gigantic. There have been no satisfactory explanations for this. To make matters even more interesting, there seems to be a mid-eclipse brightening. How can this be? One explanation, according to James Kemp, is that the eclipsing body is a giant cloud of gas enclosing two small stars in orbit around each other. These stars sweep out an area in the middle. It would be a bit like a giant donut. This donut must be tilted such that as it eclipses the primary star, the system's total light decreases and the "donut-hole" allows some of the primary star's light to sneak through at mid-eclipse.

To try to unravel this system's mystery, a concentrated effort was undertaken during the 1982-1984 eclipse. Hundreds of astronomers, amateurs and professionals, from around the world, observed the eclipse. Space born satellites observed in the ultraviolet and infrared. Ground based observations were photometric, spectroscopic, and polarmetric. Photometric observations were made with UBV filters, narrow band filters, and at wavelengths into the far infrared. Despite the concentrated efforts, epsilon Aurigae remains a mystery. The secondary eclipse was due to occur around 1996/1997. Detection of the secondary eclipse light variation is on the order of the out-of-eclipse variations. This makes separating the two periods very difficult. An effort is underway to try to predict the pulsations through continuing observations. If these pulsations can be predicted, observation of the secondary eclipse may be possible.

For those astronomers (both professional and amateur) interested, while the next eclipse will not start until August of 2009, now will be a good time to join a campaign and get prepared. Also, more out-of-eclipse observations are needed before the next eclipse.

Epsilon Aurigae is anything but quiet out-of-eclipse. A seasonal 68 day period that seems to be gradually increasing in amplitude is being seen. There are many surprised yet to be found with this interesting star system. Surely, by the end of the next eclipse, astronomy will have unraveled the mystery of epsilon Aurigae.

The History and Evolution of the Disk theory for Epsilon Aurigae

 


INDEX

* Basic System Data

Star Chart
Star Information

* Campaign Members

How to Join
How to Contribute
Member List

* 2009 - 2011 Campaign

Newsletter #1
Newsletter #2

Newsletter #3

Newsletter #4
Newsletter #5
Newsletter #6
Newsletter #7

Newsletter #8
Newsletter #9
Newsletter #10
Newsletter #11
Newsletter #12
Newsletter #13

Newsletter #14

Newsletter #15
Newsletter #16
Newsletter #17
Newsletter #18
New

* Photometry

UBVRIJH
Photometry Data
Observers
DSLR
How To
Plots
Archives
References

* Spectroscopy

New
Robin Leadbeater is now handling the submission of Spectroscopic Data

High Resolution
Low Resolution
Observers
How To
Spectra
Line Profiles
Archives
References

* Polarimetry

Basics - TBD
How To - TBD
Data - TBD

* References

1982 - 1984 Campaign
Newsletters

NASA Reference 2384
(.pdf 4.9 MB)

Current References
Interpretation
Resources

IBVS Articles
History

* Similar Star Systems

BM Orionis
Zeta Aurigae

EE Cephei
VV Cephei

* Links

Summary of 1982 - 1984 Eclipse

Current 2009 Eclipse Predictions


Sign up for the latest on epsilon Aurigae
Epsilon Aurigae News List
http://tech.groups.yahoo.com/group/EpsilonAurigae

2009/10 Composite Photometric Plots
UB, RI & V Bands as of 29 August 2010

Pre-Ingress. Ingress and Totality

V Band Composite Plot

B and U Band Composite Plots

R and I Band Composite Plots

NEW! All UBVRI Data Archive


Citizen Sky

For our Campaign to be acknowledged by the AAVSO Dr. Matthew Templeton has asked me to provide information and a link to the Citizen Sky Project.

The Citizen Sky Project is a nonscientific project coordinated by the AAVSO. They are running a Campaign centered on epsilon Aurigae. The Citizen Sky Campaign is eliciting non-astronomers and nonscientist to contribute to the Campaign. Their mission statement is

Citizen scientists are volunteers, many of whom have no prior scientific training, who work with trained scientific researchers to answer real-world questions.

People are requested to submit visual observations of the star system, both with and without optical aid.

Dr. Bob Stencel and physics graduate student Brian Kloppenborg are providing a much needed sense of professionalism to the Citizen Sky Project.

August 2009 Citizen Sky Workshops
Created and Presented
by
Jeffrey L. Hopkins
Hopkins Phoenix Observatory

DSLR Photometry
(ppt 4 MB)

DSLR Photometry
(pdf 1.4 MB)

Spectroscopy
(ppt 8.9 MB)

Spectroscopy
(
pdf 2.5 MB)

Article
The Very Long Mystery of Epsilon Aurigae
Robert E. Stencel
Sky & Telescope, May 2009 Page 58

***********************************
SAS 2009 Papers

Epsilon Aurigae, 2009: The eclipse begins
observing campaign status (.pdf)

Epsilon Aurigae
Hydrogen Alpha Emission Line Variation
The Horn Dance (.pdf


New! SAS 2010 Papers

Epsilon Aurigae Eclipse 2009 - Ingress (.pdf)

Epsilon Aurigae Eclipse 2009 - Ingress (.ppt)



Book
Epsilon Aurigae

A Mysterious Star System


AAS Poster Paper January 2010
Epsilon Aurigae
Two Year Totality Transpiring


Images from the 2010
SAS Symposium
Big Bear, California
11-13 May 2010


Astronomical Time

It is very important that anyone who makes astronomical observations understands astronomical time

 


Epsilon Aurigae Star System
Schematic Diagram


Created: 30 May 2006
Modified: 01 September 2010

Web page background artwork by D. Egge (c)1985, with permission

Webmaster: HPO SOFT