Physics for Dummies: At the Penalty of Sounding Real Stupid

[Zipper730]

Where would you find that?

 

[gumbyk]

Where would you find that?

talk to an astrophysicist. And I suspect that the equations aren't as simple as you'll want them to be.

 

[gumbyk]

Oh, and it's a variable star, so the output fluctuates...

 

[Zipper730]

I figured there'd be some kind of website that had loads of data on stars. Hey, there's data on obscure WWII aircraft I can find...

 

[mikewint]

Beta Orionis or Rigel is actually a four star system but only very large telescopes can resolve the three faint companion stars.
Depending on the source, data about Rigel are varied. In general it is roughly 870 Light-Years from the Earth and is the 7th brightest star in the sky (5th in the northern hemisphere). It is a variable star about 10 million YO (Sun is 4.5 Billion YO) that has already exhausted all of its core hydrogen fuel. A blue-white giant it will progress to a red-giant that will colapse before going super-nova. It is (depending on source) 47,000 time more luminous than the sun with a surface temperature of 21,000F (10,000F for the Sun) total energy output 120,000 times that of the sun. At a distance of 1 AU the energy would be comparable to being a few millimeters from a welding arc. The sun has an energy output of 3.846 X 10^26 Watts/sec at 93,000,000 miles the earth receives 1370 Watts/m^2 so multiply by 120,000 for Rigel. Put the Earth at this distance from Rigel and it would be quickly vaporized and blown away by Rigel's intense solar wind

 

[Zipper730]

Beta Orionis or Rigel is actually a four star system but only very large telescopes can resolve the three faint companion stars.

That, I didn't know. That's pretty cool to know, however.

Depending on the source, data about Rigel are varied. In general it is roughly 870 Light-Years from the Earth and is the 7th brightest star in the sky (5th in the northern hemisphere). It is a variable star about 10 million YO (Sun is 4.5 Billion YO) that has already exhausted all of its core hydrogen fuel. A blue-white giant it will progress to a red-giant that will colapse before going super-nova.

If it's exhausted all it's hydrogen fuel -- why isn't it a red-giant already? Generally when hydrogen-hydrogen fusion can't maintain the hydrostatic equilibrium, it will collapse until heavier elements fuse.

It is (depending on source) 47,000 time more luminous than the sun with a surface temperature of 21,000F (10,000F for the Sun) total energy output 120,000 times that of the sun.

Diameter of Rigel is over 70 times the sun.

1. Sol
   • Radius: 696,347.06 km
   • Diameter: 1,392,694.11 km
   • Circumference: 4,375,277.59 km
   • Surface Area: 3,786,277,718,182.44 km^2
2. Rigel
   • Radius: 48,744,293.88 km
   • Diameter: 97,488,587.75 km
   • Circumference: 306,269,431.086 km
   • Surface Area: 18,552,760,819,093,931.07 km^2

With that computed out, I left out some decimal places, and with the speed of light computed in as 299,792.458 km/s, 9,460,536,207,068.016 km is covered in one year, with
8,230,666,500,149,173.92 covered after 870 years.

That yields an effective surface area that Rigel's energy output would be distributed over an area of about 8.51294590298246036 x 10^32 km^2. (I could be off by a factor of one because I'm a bit rusty with scientific notation.