Star Stuff

[Magjick]

yeah, well, ya get the point.... post about the stars

[Legatus Legionis]

about stars and stuffs?

why don't you try using the search button/function of this forum.

[Pax Unum]

A star is a massive, luminous ball of plasma. Stars group together to form galaxies, and they dominate the visible universe. The nearest star to Earth is the Sun, which is the source of most of the energy on Earth, including daylight. Other stars are visible in the night sky, when they are not outshone by the Sun. A star shines because nuclear fusion in its core releases energy which traverses the star's interior and then radiates into outer space. Almost all elements heavier than hydrogen and helium were created inside the cores of stars.

Astronomers can determine the mass, age, chemical composition and many other properties of a star by observing its spectrum, luminosity and motion through space. The total mass of a star is the principal determinant in its evolution and eventual fate. Other characteristics of a star that are determined by its evolutionary history include the diameter, rotation, movement and temperature. A plot of the temperature of many stars against their luminosities, known as a Hertzsprung-Russell diagram (H-R diagram), allows the current age and evolutionary state of a particular star to be determined.

A star begins as a collapsing cloud of material that is composed primarily of hydrogen along with some helium and heavier trace elements. Once the stellar core is sufficiently dense, some of the hydrogen is steadily converted into helium through the process of nuclear fusion. The remainder of the star's interior carries energy away from the core through a combination of radiative and convective processes. These processes keep the star from collapsing upon itself and the energy generates a stellar wind at the surface and radiation into outer space.

Once the hydrogen fuel at the core is exhausted, a star of at least 0.4 times the mass of the Sun expands to become a red giant, fusing heavier elements at the core, or in shells around the core. It then evolves into a degenerate form, recycling a portion of the matter into the interstellar environment where it will form a new generation of stars with a higher proportion of heavy elements.

Binary and multi-star systems consist of two or more stars that are gravitationally bound, and generally move around each other in stable orbits. When two such stars have a relatively close orbit, their gravitational interaction can have a significant impact on their evolution.

From Wikipedia...

[keithisco]

yeah, well, ya get the point.... post about the stars

Post a question about the stars then!!

[Magjick]

Post a question about the stars then!!

ok.... Black Holes... how are they different to White Holes? (hey, you asked )

[Pax Unum]

ok.... Black Holes... how are they different to White Holes? (hey, you asked )

The only potential difference between them is in the behavior at the horizon.

Hawking argued that white holes are the same as black holes, once quantum mechanics is taken into account.

from Wikipedia...

[Magjick]

ok......

[raoulduke666]

ok hmm a question about stars...ok...how do scientists/astronomers measure how far away stars are? i cant fathom 1 light year let along 50-100 or even a million.

[Picturesque Orion]

yeah, well, ya get the point.... post about the stars

Well we have a whole board to post about the stars, planets, the universe and everything else related to astronomy. We don't need a certain topic to post discussions about the stars, planets ect.......

Edited September 21, 2007 by Alex01

[camlax]

ok hmm a question about stars...ok...how do scientists/astronomers measure how far away stars are? i cant fathom 1 light year let along 50-100 or even a million.

We measure a stars distance based on luminosity and color.

Rather than type a super long post of explanations here is nice summing up.

Parallax

Parallax example problem

Inverse Square Law

Stellar Distances at the university of HK, very good site

[signal7]

The most fascinating fact that's been recently divulged by top-rated scientists: is that they are not in fact great balls of gas. But rather, many, many elements; i.e., fusion=something.

This little tid bit came about when the solar compounding of interference led many to believe that couldn't yak, and bellow as much. HaHa!

Seriously, I don't know how often I heard that they were nothing more than the simplest of elements, H2.

When interactions became understood as such, we learned they did in fact form the planets, solar systems, by 'casting' off material.

I wonder how many systems have an inner-folded, duality where the fusion leads to gold and platinum being thrown about wildly, only to leap elsewhere?