Apparent magnitude of Orion stars

Answer 1

There are 81 stars in the constellation which appear in the Bayer/Flamsteed catalogues. Eight of these are brighter than an apparent magnitude of 3.0 The seven which from the notable hour-glass outline are:

• Betelgeuse (Alpha Orionis).
  
• Rigel (Beta Orionis)
  
• Bellatrix (Gamma Orionis),
  
• Mintaka (Delta Orionis),
  
• Alnilam (Epsilon Orionis),
• Alnitak (Zeta Orionis) and
• Saiph (Kappa Orionis).
  

Of course, as with any constellation, there are stars which are so faint that they have not yet been detected and so have not had their magnitudes measured.

Answer 2

The apparent magnitude of stars in the Orion constellation ranges from around 0 to 2. Some of the brightest stars in Orion are Betelgeuse (magnitude around 0.5), Rigel (magnitude around 0.1), and Bellatrix (magnitude around 1.6). These stars are easily visible in the night sky.