what is a star?

Question

how is it created, how is it form how long does it last? what is a falling star?

Answer 1

Stars are giant balls of burning gases, mostly hydrogen and helium. They form as a result of supernovae (the destruction of a star) in nebulae. They generally last about 5-15billion years, and end in various phases (black hole, dwarf, pulsar, supernova). A "falling star" is actually not a star at all. It is a meteorite or piece of spacial debris that enters earths atmosphere and burns as a result of air friction in the upper atmosphere, creating "shooting star" effect.

Answer 2

"...how is it created..."
New stars begin in vast clouds of gas and dust. Denser regions in such clouds allow gravity between gas and dust particles to attract each other, thus growing into a larger and larger sphere. As the sphere becomes more and more dense its center heats up more and more until it's hot enough for nuclear fusion to begin. A new star is born..!

"...how long does it last..."
This depends on how big the star is. Generally speaking, the larger the star the shorter will be its life, often not much more than several million years. Smaller stars, like our own sun, can have lives billions of years long.

"...what is a falling star..."
It's not really a star at all but instead just a chunk of rock or metal that's been drifting in open space until Earth's gravity catches it and pulls it down towards the surface. As this chunk speeds downward it heats up due to friction with our atmosphere and glows, often leaving behind a bright tail.

Answer 3

A star is a huge,more or less,spherical mass of glowing gas, emitting large amount of radiant energy.There are three important types of stars.
(1) double and multiple stars,
(2) Intrinsically variable stars and
(3)Novae and super novae.
Stars are born out of gas and dust that may exist within a galaxy.A star is believed to form from a condensation of interstellar matter,which collects by chance and grows by attracting other matter towards itself as a result of the gravitational field.This initial cloud of cold contracting matter is called a protostar.
In a star, the release of nuclear energy at the centre balances the inward gravitational force.Eventually,however,this period of stability comes to an end,because the thermonuclear energy generated in the interior is no longer sufficient to counter balance the gravitation contraction.The helium formed by fusion collects at the centre.When the helium has all been consumed there is a catastrophic collapse of the whole massive structure,resulting in a supernova explosion.Thereafter, the burnt out ramnants become neutron stars and black holes.Thus the star become a dead ball of highly compressed matter.That is the end of the star.

Answer 4

A star is created when gas in a nebula condenses and heats up. This is the birth of the star. Depending on its size it could last from a million to a billion years.

Answer 5

A star is Julia Roberts created by Hollywood executives. A falling star is Britany Spears.

Answer 6

A star is a mass of incadescant gas, a gigantic nuclear furnace, where hydrogen is formed into helium at a temperature of millions of degrees. A star is hot, a star is not a place where we could live, but here on earth, there'd be no life without the light one gives.

Hehe, I like TMBG.

Seriously, the sun is a star, a fairly typical one. They form from giant clouds of mostly hydrogen. Due to gravity, the gas clumps into huge balls, growing larger and larger, and squeezing the gas inside harder and harder.The sheer mass of gas eventually causes nuclear fusion, which emits huge amounts of energy.

The life span of a star depends on a lot of things, but mostly how big it is, and can vary hugely. But it is measured in millions and billions of years.

A shooting star, is not even closely related. A shooting star is a small piece of space rock burnign up as it collides with Earth's atmosphere.