Astrophysics lecture notes ppt

Thousands of asteroids are seen librating around Jupiter’s L4and L5points; such objects are often termsTrojans.
If given sufficient impetus
The test particle can be sent into ahorseshoe orbit
Wherein it oscillates around most of the system (as viewed from within the rotating frame).

The two most important cases in astrophysics are a classical
Non-relativistic gas of atoms and a gas of photons.
In the first case
We can derive the momentum distribution np noting that the states describing a free particle are labelled by the continuous three-momentum p.

Binary Observations d
We can then directly determine a as well (or both a1and a2if we see both components).
The first known astrometric binary was the bright
Northern star Sirius – from its motion on the sky
Astronomers first identified its tiny
But massive white dwarf companion

An alternative set of parameters often used in the study ofstellar evolu- tion(the birth, growth, and death of stars) would be the star’s mass, age, and the amount of heavier-than-helium elements in the star

Since most of the uni- verse (and stars) are made of H and He, astronomers call all elements heavier