Astronomy - Ch. 17: The Nature of Stars (36 of 37) Determining the Mass of of a Binary Star: Example

[@suguinify]

I'm starting my proyects to do my thesis about binary stars, specifically about DQ Her, i was really stuck trying to understand the process of the mass calculation, this video and the one before really explained it super easy, Thanks. Excellent work you are doing. Hats off for you.

[@MichelvanBiezen]

Good luck on your project. You may also want to look at this: ASTROPHYSICS 1 BINARY SYSTEMS & KEPLER'S LAWS

[@0219-n1e]

some times I think astronomy is like a very smart ant measures a building. such a wonderful field of study.

[@aaron7392]

Can you do a triple star system?

[@Walter-uy4or]

That was a great explanation. I have seen this with much more complex equations, i.e., m1m2 d2rvec/dt2 = -(m1+m2) Gm1m2/r2 r hat. My IPad does not have scientific notation. Please forgive the form. I still do not understand this, especially since r hat was never defined (I know it has a unit of 1, but how is that relevant?).

[@MichelvanBiezen]

There are different methods, one of them used the "reduced mass" concept (see our astrophysics videos). But this method shown will work just fine.

[@dalevillarin8662]

How can you determine the distance between the two stars?

[@prakashkumarprakashkumar3959]

How measure the mass of any black hole

[@MichelvanBiezen]

We observe the effect a black hole has on other objects revolving it. (That is how we measure the mass of the Earth, by observing the effect it has on the Moon or a satellite.)

[@prakashkumarprakashkumar3959]

How it's possible

[@MichelvanBiezen]

We have a number of videos in the physics playlists (under gravity) that explain that. Essentially we set the cetripetal force equal to the force of gravity and we can solve for the mass.

[@MichelvanBiezen]

Don't forget I work 3 jobs besides working on these videos.

[@0219-n1e]

@@MichelvanBiezen Very well. what are those?