Gamma

Approaching Bellatrix, with the Sun directly behind us, as shown in Celestia. The slightly-distorted shape of Orion can be seen behind.

Gamma

Bellatrix – a blue-ish pixel,
Fairly bright, as bright stars go.
Drifting lonely through Orion –
Closer than her neighbours, though.
That means she must be smaller –
And she’s just too small to go off pop –
Strange that seven solar-masses
Makes her baby of the crop.
Was she born, like many of her cohorts,
In Orion’s cloud ?
Maybe not – perhaps adopted,
Hanging with the big boys’ crowd.
But they’ll grow tall and all be gone one day,
While she’s a quieter kind –
She may turn red, but end up white,
Forever left behind.

If we take a look at the vital statistics (according to Wikipedia, and I’ve rounded them off a bit) of the eight brightest stars in Orion, they are (by descending declination):
Meissa – a double star: A is ≈28 solar masses, B is ≈10 solar masses.
Betelgeuse – ≈16-19 solar masses, depending on how far away he is, which is surprisingly hard to determine.
Bellatrix – There seems to be some confusion as apparently Bellatrix is older that a star of her mass should be (7-8 solar masses) without having evolved into a giant, and it has been suggested that she is infact twins – a spectroscopic binary of two smaller, longer-lived stars, which would presumably make her Bellatrices ?
Mintaka – a multiple-star system, but we’ll only worry about the two most massive: Aa1 is ≈24, while Ab is ≈22.
Alnilam – a whopping 40-44 solar masses.
Alnitak – again a multiple, Aa is ≈33, Ab a mere 14 or so.
Rigel – brightest of the lot (from our perspective) and another collective, with the main component being ≈21.
Saiph – and finally, a ≈15 tiddler to round us off.
Of these, all bar Betelgeuse are hot blue stars, but anything of a similar mass (so 20-ish or less) will presumably follow suit and swell up in the next few million years before exploding in a blaze of glory and leaving behind a neutron star.
The fate of the heavyweights is less clear – they’ll certainly go super, but may never turn red, and some if not all of these will simply implode into a black hole denying us the spectacular brightening.
Anything over ≈8 solar masses is thought to end as a Type II (though future bouts of mass-loss complicate things), with Bellatrix thought to be just too short to ride that particular rollercoaster.

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