are stars made of gas?

Question

what are they made of?

Answer 1

Yes and no. When stars are formed from a gaseous nebula, it is primarily hydrogen and helium that concentrate into a small volume (compared to the extent of the original cloud). Once enough mass has accumulated, though, the atoms of gas begin to be stripped of some or all of their electrons and the result is a plasma. The center of stars is so densely packed that a handful of the plasma would weigh tons. There, the atoms are so tightly packed that they begin to fuse into heavier atoms (elements), and would resemble an extremely dense "solid" if we could scoop up a sample.

Answer 2

Stars are mostly made of hydrogen, the simplest atomic element, which is a gas at room temperature and pressure. Inside stars, the gravity and pressure are tremendous, so what would be a gas becomes increasingly liquid-like, and then solid-like as one looks deeper inside the star. Essentially protons, neutrons, electrons and assorted particles are jammed together in an atomic stew. The star fuses protons and neutrons together, making hydrogen into helium. Once the hydrogen is all used up, the star's gravity / pressure balance becomes unstable, usually expanding it tremendously for a while, then collapsing into a new fusion engine that fuses helium into lithium, boron and other heavier elements. By the time it is able to fuse iron, it is just about dead. Some stars don't quite regain their equilibrium and explode instead, scattering what they've made to the cosmic winds. These remnants recombine into new stars and planets, but it takes more time than you can imagine.

Answer 3

As far as we know all stars are made up of mostly hydrogen. when in its simplest form is a gas. However, when hydrogen is heated and compressed, it inters into a different stage. As in a stars case, hydrogen becomes ionized. The electrons spinning around the nucleus has collapsed and is no longer protecting the nucleus. The center of a star is so hot and dense that it transforms hydrogen into helium. This transformation gives off a tremendous amount of energy which we see as light. Our sun has all of the elements. but is mostly 90% hydrogen and About 10 helium.

Answer 4

Strictly speaking, stars are made of plasma; they are too hot for atoms to form. The electrons and nuclei have so much energy that the binding energy [ionization energies] are so small compared to the thermal energy that they fly apart.

Don't look for solids or liquids in a star, not at those temperatures.

The apparent surface temp of sun as seen from earth is 5400 k inside is a whole lot hotter

Answer 5

It depends on the star type. A black hole is made out of who-knows-what. A neutron star is made of mostly neutrons, which behave like a liquid. Most stars of made of hydrogen plasma (ionized gas).

Answer 6

When a star the mass of our Sun uses up its nuclear fuel, it expels most of its outer layers to leave just a very hot core called a white dwarf. Scientists had speculated that at the bottom of a white dwarf’s 31 mile (50 kilometer)-thick crust was crystallized carbon and oxygen, similar to a diamond.

And in 2004, they found that a white dwarf near the constellation Centaurus, BPM 37093, was made of crystallized carbon weighing 5 million trillion trillion pounds. In diamond-speak, that’s 10 billion trillion trillion carats.

Answer 7

definite and no, an universal (if there is this kind of element) stars existence cycle is going something like this.... Stars are born in nebulae the position hydrogen gas condenses and warm temperature and rigidity builds up. This motives fusion to take position and hydrogen will change into helium generating extra warmth and mild. subsequently the ball of gas begins sparkling and we call this a movie star. The helium then variations in to the subsequent element contained in the periodic table etc etc, as rigidity and warm temperature develop, till on the centre of the movie star we get heavier elements. truly heavy elements are formed even as the movie star dies and the rigidity is gigantic. each of the elements contained in the universe are born in stars. eventually the movie star burns out each of the hydrogen thats round them, which leaves purely hydrogen so the rigidity is redeuced. They then both start up to blow up or implode or both. Our sunlight will first strengthen then contract in about 5 billion years to form a pink huge. each of the elements are then both flung out in to area or perhaps the movie star will form a black hollow and the elements will finally end up interior it. i desire this facilitates, if no longer e-mail me

Answer 8

sorta

gases, liquids, solids are phases of matter we are familiar with at normal temperatures and pressures.

The Sun's surface is about 5000 degrees, hardly 'normal' for us here on Earth, and that's the least of it! In the corona the temp is more like a million degrees and in the core, even hotter!

Matter does odd things at those temps, stripping away electrons and flowing 'like' a gas, yet not a gas. We call that phase 'plasma'.

Answer 9

Stars are made up of Hydrogen gas.Stars are fueled by the fusion of 2 hydrogen atoms.The fused hydrogen atoms become helium atoms.The center of a star is a huge hydrogen fusion reactor.Helium is the by-product of this atomic reaction,thus stars also have helium in them.

Answer 10

in the first stages of star birth, gases are the main ingredient and as it coalesces it's gravity attracts small particles and then larger particles and as it snowballs the heat from the pressure becomes enough to ignite fusion and a star is born. it then absorbs everything it can and burns the hydrogen out and converts it into heavier elements and so it goes. read this article:
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Stellar Birth

Stellar Life Tertiary Navigation

Overview

Nebulae, discussed in the Nebulae page of this section, are what form stars. However, it takes a long time before a nebulae becomes a full-fledged star. The steps and processes that form stars from these vast clouds of dust and gas is the topic of this page.

The basic process of star formation is that they emerge due to accretion of enough matter to reach a critical mass* of approximately 80 times Jupiter's, at which point internal pressures raise the core temperatures high enough to ignite nuclear fusion.

*Brown dwarfs are a type of failed star. They do not fuse hydrogen and so are technically not considered to be stars. They do not fuse because their masses are below approximately 80 times Jupiter's, so there is not enough pressure to raise internal temperatures to those necessary for fusion. If two brown dwarfs were to merge, and the resulting body had more than that critical mass, then it would theoretically start fusion and become a bona fide star.

Gravitational Collapse

The first step in the birth of a star is to wait. Dust, gas, and other materials sit around in nebulae, and wait for eons until a passing star, shockwave, or other gravitational disturbance passes through or by the nebula.

Once this happens, its gravity causes swirls and ripples. It would be like spreading marbles out on a trampoline, and then rolling a large lead ball around the edge, or through the middle. The other marbles would roll around, and clump together near the path the lead one took. It is no different in a nebula when a star passes by. To add to the marble analogy: When the marbles gather in places, the dip in the trampoline causes other marbles to accumulate in the same spot until there are just a few piles of marbles, with very few marbles in between. This process is called accretion, and causes the stars - or marble clusters - to grow larger.

E=0.5*UHowever, the molecules in the nebula have energy of their own, which resist this collapse. The cloud will only collapse if its mass is large enough to allow this - a mass called the "Jean's Mass." This is derived from the Virial Theorem (left). Rearranging this, and substituting in the equations for kinetic an potential energy, the equation becomes:

Jean's Mass Derivation

R=(3M/4*pi*rho)^(1/3)Now, the number of particles in the cloud is equal to the mass of the cloud divided by the mass of the particles, N=M/m, and assuming that the cloud has a constant density, you can relate its size to its mass by the equation to the right. Rearranging, combining, and simplifying, we get the equation for Jean's Mass, MJ:

Jean's Mass

If the cloud's mass is larger than this critical mass, then it will collapse. Otherwise, it will continue to swirl and clump, but the clumps will not be permanent, and they will dissolve in the cloud.

Continuing on the road of accretion, assuming that the cloud's mass is above the Jean's Mass, the clumps of matter continue to group together in the nebula until they are gigantic clumps of dust and gas. By this time, the clumps have reached sun-like sizes, and by that stage, the gas is dense enough that it no longer loses heat to the surrounding nebula. It has become "adiabatically opaque," and the heat that it generates is retained, and it starts to heat up. At this stage, the clump is called a protostar. From the start of the collapse to this stage, typical time scales are on the order of a few hundred thousand years.

Protostars - Pre-Main Sequence

As the protostar becomes larger, gravity squeezes it tighter, causing pressure to build and for the heat to increase. If you have ever pumped a bicycle tire, you know that when the air becomes compressed, it becomes hotter.

On the Hertzsprung-Russell Diagram, the large swath of stars through the center is called the "Main Sequence," and it is where most stars live most of their lives. There is a period of time between when protostars are formed and they reach the main sequence, and this is called the "pre-main sequence."

At this point, the stars technically are still proto, not having ignited fusion. They are still contracting.

The pre-main sequence to the right shows theoretical temperature vs. luminosity of the protostars for several different masses. Low mass stars contract and drop in luminosity until the interior opacity drops and the energy comes flooding out, resulting in an increase in surface temperature and luminosity. High mass stars have low opacity to begin with due to high temperatures, and simply heat up as the contract.

Then, when the pressure in the center causes the core to reach a temperature of 10,000,000 K (18,000,000 °F), hydrogen fusion is initiated. Now, the protostar has become a star. It shines with its own light. Its solar wind quickly pushes away the rest of the dust and gas in its vicinity.

NOTE: A protostar that does not become hot enough to begin fusion, yet is no longer surrounded by its parent nebula is called a brown dwarf. A brown dwarf usually has between 1/12 and 1/100 of the Sun's mass. It can still produce heat by contracting very slowly (i.e. decreasing its equatorial diameter by a few millimeters a year), yet does not shine as a star does. Jupiter produces heat in this way, although it is too small to be considered a brown dwarf. Most brown dwarfs have an average surface temperature of 1,800 K (2,700° F). There are an estimated one trillion brown dwarfs in our galaxy alone, and some think they may be a source of the universe's missing mass.

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This page was last updated on January 11, 2006.

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