Let us start with Betelgeuse. Most likely one of the most famous of the stars. It is the second brightest star in the constellation, and the 8th
brightest in the sky. It is a "M" class red supergiant star, nearing the end of it's life.
Casting a redish-orange hue, it's very distinct in our constellation as compared to the other stars, due to it's color.
At 643 lightyears away, is has a very large radius compared to our sun. To help give you an idea of how big it is, (most common measurement is 667
solar radii), here is a picture of our solar system with the sun:
Now, here is what it would look like if we replaced the sun with Betelgeuse:
Oooooo. That's big.
So, how old is Betelgeuse? Since it's a red supergiant, it must be a very old star, right?
Well, it's old for a Class M supergiant. It's about 10 to 12 million years old.
Yes, you read that right, and it's not a typo by me. Betelgeuse is only 10 to 12 million years old. Class M supergiants with the same mass as
Betelgeuse only exist for about 10 million years or so as a Main Sequence star, and is now at the end of it's life. Because of it's huge mass, it
burns it's hydrogen fuel at a incredible rate, and kills itself early on, as compared to a much lower mass star like our sun (class "G") which
stays on the Main Sequence for billions of years.
So it will most likely go Supernova soon.
Oh, but don't hold your breath. "Soon" to astronomers is sometime in the next million years or so.
Betelgeuse is well known in pop culture too:
Author Douglas Adams in his book "Hitchhiker's Guide" refered to one of his main characters being "from the vicinity of Betelgeuse".
is also the name of a popular 80's movie by Tim Burton. Staring Michael Keaton, unlike
the tittle, his character's name in the movie is actually spelled "Betelgeuse" like the star.
Rigel is next on the list and is the brightest star in the constellation, and the 7th brightest star in our skies.
Riglel is a blue supergiant that is actually a triple star system. The bright star we see with our naked eyes, Rigle is designated as "Rigel A" in
it's own system, with two much dimmer blue white stars known as Rigel B.
Rigel itself being a Spectral Class "B" star, outshines our sun by 130,000 times. It is 18 times more massive than our sun, and has a radius that is
74 times bigger than our sun.
This is what it would look like if we replaced our sun with Rigel:
Earth's surfact temperature would be at 5,756 deg C....but not for long, as it would quickly be pulled into Rigel.
Rigel has been used in pop culture quite a bit, especially in Star Trek,
Also in comic books and even computer games such as Star Control II,
Duke Nukem II,
and even Frontier: Elite II
Bellatrix is next, and may be a name you are familiar with from the Harry Potter series as one of the characters in J.K. Rowling's books is named
Bellatrix is a Spectral Class "B" star that is blue white. It has 8.4 times the mass of our sun, and is about 6 times bigger than our sun in size.
It is VERY hot with a surface temperature of about 22,000 K (our own sun is at 5,778 K). Our planet would be a burned cinder if we were to replace the
sun with Bellatrix.
As with the other stars in Orion, Bellatrix is about 20 million years old., and is the closest of all the stars in Orion to us.
Another piece of trivia: Bellatrix was the star system that the astronauts in the original 1968 film "Planet Of The Apes" were trying to reach, and
when they crashed, actually thought they were there:
Mintaka is next, and is one of the "Belt" stars of Orion's Belt.
Mintaka is a multiple star system consisting of 4 stars, with the main two stars visible to us. Mintaka A, a Class "B" star, and Mintaka B, a Class
Both stars mass 20 times bigger than our sun, and are about 15 times larger in size than our sun.
Mintaka was featured in an episode of Star Trek: TNG:
and during World War 2, the U.S. Navy had a cargo ship named after the star, the USS Mintaka AK94.
Alnilam is the next "Belt" star.
Alnilam is a Spectral Class "B" star that is 30 times bigger than our sun. It is the most distant of the 7 brightest stars of Orion, and while it
does not appear as the brightest in the constellation, it is the most luminous of them, outshining our sun by 375,000 times brighter.
It's surface temperature is 26,000 K.
Alnitak is the last of the three "Belt" stars of Orion.
It is a triple star system, the primary being a Spectral Class "O" (and is the brightest Class O star in the night sky).
Alnitak has 27 times the mass of our sun, and is 19 times bigger than our sun. It also outshines our sun by 180,000 times with a surface temperature
of 28,000 K.
This star is a bit famous as right next to it are the Flame Nebula and just below it is the Horse Head Nebula:
The U.S. Navy also had another World War 2 ship named after this star, the USS Alnitak AK-127, a cargo carrier.
The original Star Trek series featured it's episode "The City on the Edge of Forever", in which Captain Kirk struggles to recall a book written
around 2030 from a author who was from "a planet circling that far left star in Orion's Belt":
Last of the seven brightest stars of Orion is Saiph.
Saiph is a Spectral Class "B" supergiant star. It has 15 times more mass than our sun, and is 22 times bigger than our sun, with a surface
temperature of 26,500 K, and is about 11 million years old.
So some interesting things to note about these 7 stars of Orion:
1) They are all supergiants, much bigger than our sun, much hotter, much brighter.
2) They are all very young compared to our sun, each being under 20 million years old.
3) Being supergiant stars, they have much shorter lifespans than our sun, measured in only tens of millions of years.
4) No planets have been detected around these stars, and planet formation around them is highly unlikely due to the speed of their stellar winds,
which not only casts large amounts of mass from themselves, but tend to "blow away" any left over stellar medium that would normally result in the
formation of planets.
5) The majority of these stars will end their lives as a Type II Supernova.
We could most likely move on and talk about other objects that are in the Orion Constellation like the Orion Nebula and the Horse Head Nebula, but
each of those objects really rate a thread of their own, considering the complexity of each object.
So for now, I hope you enjoyed learning a bit more about this very famous constellation, even if only some trivia from it, and please, when you go out
at night, look up and enjoy it. I know I do everytime I see it, like greeting a old friend.