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This web site is acting as the International Zeta Aurigae Campaign Web site for the 2011 eclipse of the star system.

Zeta Aurigae Star System

The zeta Aurigae star system is a 4th magnitude system with a period of 2.66 years. It consists of a very hot and luminous blue star plus an even more luminous orange super giant star. Because of the vast difference in sizes, only the primary eclipse where the orange super giant passes in front of the smaller blue star, is observable. Along with the other star systems listed here, the zeta Aurigae system allows observations of the chromospheric, or outermost layers, of the orange super giant star. By careful observations during the ingress and egress phase of the eclipse, information about the super giant's atmosphere can be gained.

As might be expected, the UBV observations of the eclipse will produce a small change in the "V" (0.1 to 0.2 magnitudes) but nearly 2 magnitudes of change in the "U" band.

Reference: Darling, D., 1983, Astronomy; The Curious Case of Zeta Aurigae, 66-70, March 1983

1985 and 2006 Eclipse Plots

Documentation

Distance: 1300 light years (400 pc)

Epoch: JD 2,438,386.525
Period: 972.164 days 2.7 years

From recent paper
Epoch: JD 2,438,386.540
Period: 972.183 days 2.7 years

Note: Epoch is mid-Eclipses

Secondary Eclipse at Phase: 0.27

Ingress/Egress: ~4 days
Totality: 37 days

Next Eclipses:
2,455,864 * 29 October 2011
This is based on the 1985 eclipse

Secondary Eclipses:
2,456,125 * 16 July 2011
(261 Days from 1st contact)

Maximum Separation Date - ?

Summary

From 1996 Zeta Aurigae Epoch - 2,438,386.525
Period = 972.164 days

1985 Eclipse
1st Contact JD 2,446,142.7
17 March 1985

2006 Predicted 1st Contact JD 2,446,137.645 2006
Actual 1st Contact unknown

Predicted 2011 Mid-eclipse from Epoch JD 2,455,885
19 November 2011

From 1985 Eclipse

Predicted 2011 1st Contact JD 2,455,864
29 October 2011

Predicted 2011 2nd Contact JD 2,455,868
02 November 2011

Predicted 2011 Mid-Eclipse JD 2,455,886
20 November 2011

Predicted 2011 3rd Contact JD 2,455,905
09 December 2011

Predicted 2011 4th Contact JD 2,455,909
13 December 2011

ZETA AURIGAE

Zeta Aurigae or 8 Aurigae
HR1612 HD32068
Name: Sadatoni
Part of "The Kids"

R.A. (2000) 05h 02m 28.6s
DEC. (2000) +41d 4' 33"

Comparison Star:
Lambda Aurigae
HR1729
HD34411
SAO40233
R.A. (2000) 05h 19m 08.4s
DEC. (2000) +40d 05' 57"
I= 3.88 R= 4.19
V= 4.71 B= 5.34 U= 5.46

zeta Aurigae
Out-of-Eclipse
Magnitudes

Zeta Aurigae Out-of-Eclipse Spectra

Eshel Spectrum Line Profile by Olivier Thizy 30 August 2009 Visible Spectrum
The above spectrum is very high resolution and as such can be expanded to resolve finer detail as seen below with the expanded sodium D line, hydrogen alpha and beta regions,

Eshel Spectrum Line Profile by Olivier Thizy 30 August 2009 Sodium D line Region

Eshel Spectrum Line Profile by Olivier Thizy 30 August 2009 Hydrogen Alpha line Region

Eshel Spectrum Line Profile by Olivier Thizy 30 August 2009 Hydrogen Beta line Region

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