Castor

[vindictive666 (John)]

gday all

i learned someik new today

i knew that castor was a double also knew that it had triple (c i think its called)

but apparently these doubles are doubles themselves confusing or what ?

more info here


http://schmidling.netfirms.com/doubst.htm


(vewy vewy interesting)

rats need someik like the hubble to see those

[[1ponders] (Paul)]

That's Castor for you, a triple double, or is that a double triple, or is that an eclipting sextuplet Yep that's right there are actually 6 stars there, three pairs

[ballaratdragons (Ken)]

That little fella hiding (circled) is a sneaky little beggar!

Don't thinks me scopes will see him! (ever)

[[1ponders] (Paul)]

Here's a quote from the "National Audubon Society - Field guide to the Night Sky"
Quote

"Gemini
alpha is Castor, second brightest star of Gemini. To the unaided eye Castor appears a a single star of spectral type A1 V and magnitude 1.6, but it is actually a sextuple. Through a telescope it looks like two stars of magnitudes 2 and 3, only 2" apart, with a 9th magnitude companion 73" from them. Each of these three stars is itself double. The system of stars is 46 ly from Earth."

End Quote.

[[1ponders] (Paul)]

If you want to check out a really interesting multiple star try gamma Vela.

Its actually the brightest star in the constellation Vela but kept its gamma designation from before the constellation Argos was broken up into Carina, Vela and Puppis. It is 5 stars but none double. They all orbit each other. Scientists are yet to work out how in this multiple situation one or more haven't collided with each other. If you get a good seeing night its quite a spectacular multiple.

Quote
"gamma is sometimes called Regor, of unknown meaning. (One explanation is that it is "Roger" backwards and perhaps honors someone of that name. To the unaided eye gama appears as a single star of magnitude of 1.8. It is really a quintuple system, its components of the following types and mangitudes (their luminosity classes are unknown). gamma Vel A: WC7 ("WC" is the designation for atype of Wolf-Rayet star, see below), 1.9; gama Vel B: B3, 4.2; gama Vel C: AO, 8.2; gamma Vel D: AO, 9.1; gamma Vel E: unknown type, 12.5. Escept for gamma Vel D and E, which are only 1.8" apart, the stars are easily resolved in small telescopes. Gamma Vel A, the brightest star, is a rare Wolf-Rayer star, one of the hottest stars known, very blue and bright. The system is 1500 ly from Earth"

End quote

If you get the opportunity, find out about Wolf-Rayer stars, they are fascinating stars.