What kind of name is Sigma CrB A?

[PurpleFringe]

It seems Bayer designated this star Sigma 2 CrB. (http://en.wikipedia.org/wiki/List_of_stars_in_Corona_Borealis)

I know that 'A' usually means the first / brightest star in a multiple.

Does the designation Sigma CrB A have a name?

Many thanks

Andrew

[PurpleFringe]

And a follow up question - would it be possible to have 'A' or 'B' added onto a Bayer name?

eg if it turned out the Nu 1 CrB was a double, would it be called Nu 1 CrB A and Nu 1 CrB B?

Gotta love these names

[ronin]

Does the designation Sigma CrB A have a name?

Yes it's :- Sigma CrB A  :grin:

Too many stars to call them Bob, Mike, Doris, etc.

They don't now name them as the bright ones have been named for a few thousand years, Arabic and Greek mainly, they get a designation instead of a name. Down at Sigma I suspect it was doubtful if during the naming of stars it could be seen by eye. Also being that dim it probably didn't qualify for a name.

Cloudy in London by chance?

[cantab]

Bayer used Greek letters for designations, with added superscripts more or less when he felt like it really. Some superscripts are for doubles, say Theta 1 and Theta 2 Tauri, but others are much further apart, say Pi 1 through Pi 6 Orionis.

If a Bayer designated star is later discovered to be a multiple, A and B letters will be suffixed to the designation, whether it had numbers or no. For example Bayer designated a pair of stars in the M42 Theta 1 and Theta 2 Orionis. Theta 1 is the Trapezium, with A, B, C, and D components.

[PurpleFringe]

@ronin: He he, yes it was cloudy last night. But I still wanted to know.

@cantab: Excellent example! I should have thought of the trapezium as it's lovely and I was looking at it on Monday. Very nice.

It gets more complicated. I looked up Theta 1 Ori and found that even Theta 1 Ori A is multiple. The components are A1, A2 and A3. (http://en.wikipedia.org/wiki/Theta_Orionis). Who wants life to be simple eh?

And before you ask - it's still cloudy here.