What Determines the Evolutionary Path of Stars?

[nath_quam]

Hey, would anyone be able to tell me quality websites/ or help to answer the following questions:
1. What is a star?
2. How Astronomers can tell the difference between different stellar objects?
3. What powers a star?
4. The evelotionary path of a star and it's different stages.
5. Why Stars move though this evolutionary cycle and why the cycle is altered for stars of different mass?

Thanks for your help Nath

 

[Farsight]

There's lots of good websites, nath. Do a google search on "Stellar Evolution" and you see things like this from Nasa.

http://observe.arc.nasa.gov/nasa/space/stellardeath/stellardeath_intro.html

 

[kyle8921]

alie

I would be happy to provide some information on stars and stellar evolution.

1. A star is a massive, luminous sphere of plasma held together by its own gravity. It is primarily composed of hydrogen and helium, and generates energy through nuclear fusion in its core.

2. Astronomers can tell the difference between different stellar objects through various observations and measurements. These include the star's spectral characteristics, such as its temperature and chemical composition, as well as its luminosity, size, and motion.

3. The power source of a star is nuclear fusion, where hydrogen atoms fuse together to form helium. This process releases a tremendous amount of energy, which is what makes stars shine.

4. The evolutionary path of a star depends on its mass. Generally, stars go through several stages: protostar, main sequence, red giant, planetary nebula, and white dwarf. High-mass stars also go through additional stages, such as supernova and neutron star or black hole formation.

5. The evolutionary cycle of a star is determined by its mass because the amount of mass a star has affects its internal pressure, temperature, and fusion rate. The more massive a star is, the faster it consumes its fuel and the shorter its lifespan. This is why high-mass stars have shorter lifetimes and go through more stages than low-mass stars. Additionally, the mass of a star also determines the type of elements it can fuse, which can also affect its evolution.