Astronomical Masses Flashcards
1
Q
What is the relationship between two objects orbiting a common centre of mass?
A
M1r1=M2r2
2
Q
What is the centripetal accelration?
A
a = ω^2r
3
Q
What is Kepler’s third law?
A
ω^2=4π^2/P^2=G(M1 + M2)/R^3
Where R=r1+r2
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4
Q
What are binary stars?
A
A pair of stars orbiting a common centre of mass
5
Q
What is the doppler shift for wavelengths?
A
λ = λ0(1+vcos(θ)/c)=λ0(1+vR/c)
6
Q
What is the radial velocity?
A
Vr=Vcos(θ)
7
Q
How does the radial and orbital velocity relate?
A
vR = γ + vorb sin(i) sin(2π(t − T_0)/P)
Where i is the orbital inclination
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8
Q
What is gravitational lensing?
A
When light rays are deflected when passing near to a massive object
9
Q
What is the Einstein ring radius?
A
Θ_E =(4GM/Dc^2)^1/2
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10
Q
A
