How far apart are the stars that make up orion?

Look up this site:
http://en.wikipedia.org/wiki/Orion_%28constellation%29

Assuming that the bright stars in this constellation are around a thousand light years away, and the constellation subtends an angle of around 20 degrees as seen from Earth, you should be able to easily estimate the distances betwixt the stars.


Cheers!
 
You can calculate all that yourself, if you know how to use a calculator (a person asking this should be able to use).
1. Pick any pair of stars (tag them 1 & 2).
2. Find the differences of their Right Ascensions and declinations separately; and derive the angular separation of the pair
A = ?[(diff RA)²+(diff Decl.)²] .
Since they are all in a compact area (of constellation) the approximate formula would suffice or else
CosA = Sin(Decl1) Sin(Decl2) +Cos(Decl1) Cos(Decl2) Cos(RA1-RA2) .
3. Pick out their distances from Earth (r1 & r2). Use 'A' in this formula
r² = (r1)² + (r2)² - 2 (r1)(r2) CosA
where ' r ' is the distance you seek between the pair of stars.
 
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