Return to Home Page
Re: [AAVSO-DIS] Eta Gem Request & other LP EBs > There are a few shallow depth, long-period EBs that come due in the next > year or so. It would be nice if a better ephereris for all these stars was > available. Besides eta Gem, I show the following stars eclipsing based on > periods and dates from Burnham's Celestial Handbook. > > 32 Cyg (per = 1148d) mid-eclipse April 1, 2003 > 31 Cyg (per = 3802.84d) mid-eclipse Sept 3, 2003 > zeta Aur (per = 972.176d) begins Nov 13, 2003, ends Dec 18, 2003 > > All these eclipses last a long while - weeks or months around their mid > dates, so good monitoring needs to happen well beforehand. The visual dips > are also very small - only a few 10th of a mag in 'v'. They are thus for > CCD guys, best in redder bands. They are all zeta Aur-type ecliping binaries. In these systems, a hot star (usually main-sequence B star) is eclipsed by a (super)giant (usually K star). So the depths of eclipses are larger in short wavelengths. The depths are much more striking in the B band (good targets for B-filtered human eyes?, although I don't recommend to use a U filter...) rather than in red CCD bands. Regards, Taichi Kato
Return to the Powerful Daisaku Nogami
vsnet-adm@kusastro.kyoto-u.ac.jp
