Everything You Need to Know about Stars

I pick the star Antares, from the H-R diagram I can tell that it it is a Red Supergiant, and it has a surface temperature that is around 3,000 degrees kelvin, which is cooler than the Sun by at least 2,000 degrees kelvin, but its luminosity is around 10,000 solar units, which means it produces much more energy than our Sun does, so it is a lot brighter. The spectral type of Antares is a M, I could tell that its spectral type was M because I read the H-R Diagram, the VLab told me that the star ‘Betelgeuse’ has a spectral type of M, and Antares is right below, and basically inside Betelgeuse. Stars with the same spectral type have the same chemical composition, so Antares has the chemical composition Ca (calcium), TiO (titanium oxide), CH (methylidene).

All over our galaxy are pockets of space, filled with dust and gas. Some of these clouds are denser than others, and every once and a while, a cloud of this gas begins squeezing together due to its own gravity. This is when a star begins to form. The cloud begins to form into a rotating disk, with the inner section rotating faster than the outer. The center will begin to heat up because of the pressure and thermonuclear reactions start in its center. Eventually, two hydrogen atoms get squeezed together with extreme pressure so that they fuse into one atom of helium, releasing a massive amount of energy, when this happens; the object is now a protostar. As the star ages, it begins to run out of hydrogen, and the star starts to spasm. It is now a subgiant. The

Stellar evolution stars exist because of gravity. The two opposing forces in a star are gravity (contracts) and thermal nuclear energy (expands). Stage 1 Birth is where gravity contracts the cloud and the temperature rises, becoming a protostar. Protostars are a hypothetical cloud of dust and atoms in space which are believed to develop into a star. Astronomers are fairly certain of their existence. Protostars are formed about a million years after a gas clump from an interstellar gas cloud has started

Another property of a star is temperature. By measuring the temperature of a star, scientists are able to tell how hot the star is. They use color to measure the temperature of stars. The red ones are the coolest (3,500 K), the yellow ones are warmer (5,000 to 7,000 K), the white ones are warmer still (9,000 to 15,000 K), and the blue ones are the hottest (20,000 to 50,000 K).

The life cycle of a star is dependent on its mass. The larger the mass, the quicker it will die out, whereas stars which are no more than half the size of our Sun can live up to hundreds of billion years. However no matter how large the star is, they all begin their lives in a nursery known as a molecular cloud.

Way out there in space, there are huge clouds of dust and gas and if one of those clouds of dust and gas is massive enough it's own gravity can causes it to start to collapse. When it collapses, it folds itself towards the center of the cloud, then it get denser and denser and hotter and hotter; eventually the particles of that gas and the dust are made up and brought so close together that they start to stick together. Then they start to fuse, thats the energy source of a star. The star switches and begins to shine. Inside every newborn star, hydrogen atoms are fused together to make helium. This process is called fusion and it creates the energy of every star. A star is a luminous sphere of gas producing its own heat and light by nuclear reactions (nuclear fusion).

The life cycle of star is on an eternal cycle of birth, death and regeneration where the gases that form stars are ejected by the very stars when they die. This all starts with the helium gas and fusion of hydrogen. The life cycle of a star is formed from stellar nebula to high mass stars and low mass stars. Hertzsprung and Russell classified stars on the main sequence of the H-R diagram about 1910 that shows the relationship between luminosities and spectral types.

Stars, such as our sun begin their life in an entirely different form from the one we come to recognize. Their lives begin in the bitter cold, around 10 degrees Kelvin, which is only a few degrees above the 3 degrees Kelvin temperature of the background of space itself. Their density is also extremely sparse, with a density of around 1 billion particles per cubic metre, which is only a wisp in comparison to the density of around 1410 kilograms per cubic metre that the sun like star will have during its time on the main sequence. Although they may be quite low in density, the clouds are absolutely enormous, spanning up to tens of parsecs (an astronomical unit of measurement that is determined to be around 19 trillion miles) across. In these clouds, there is an abundance of molecular and atomic gases of various types, which will serve as the rough material that will be used to create the stars and solar systems. Hydrogen is the most abundant element found within these clouds, although they can also contain many other trace elements of metals and gasses.

a) The Milky Way is an island of hundreds of billions of stars, gas, and dust held together by gravity to form a disk

Stars go through phases with each one altering the star. They start as a protostar then ignite to

There are two different life cycles for stars but they both start out as a 'Stellar Nebula'. It then splits off in to separate stars the Low Mass and The High Mass stars..

We know of many stars that exist, but the main stars are White dwarfs, Pulsars, Neutron stars, Magnetars, Brown dwarfs, Black Holes, Cepheid Variable stars, Supergiants, Red Giants, Novas, and Quasars. Starting with White Dwarf, this star is usually the size of a planet and is last stage of a stars life, when it loses all its layers from the planetary nebula. This star is very dense and especially hot after it disables its nuclear fuel. It starts to cool done over the next billions of years. Pulsars, this star is practically a white dwarf star, but has electromagic ration beaming out of it. There are two steady lights (electromagic ration) that point in two opposite directions. It always seems to be blinking, but this is just from the motion

After carbon sinks to the middle of the star it also fuses with itself and creates oxygen and now oxygen is at the center of the star. The same process repeats with oxygen and it forms iron. Iron is the last thing that is formed because it does not produce energy, therefore it will not fuse with itself, so it forms the core of the star. The elements in these layers have formed an onion. After iron is settled in the center, the star begins to cool and the star will start to compress. When the star compresses, the temperature begins to increase and eventually the star will explode resulting in a

Stars spend approximately eighty percent of their lives on the main sequence before evolving into something else. A star leaves the Main Sequence when it has exhausted most of the hydrogen in its core, which causes it to lose equilibrium. It begins to contract again as radiation and thermal pressure decrease, and gravity dominates. Even though core hydrogen fusion ceases, energy is still generated in the core because of gravitational contraction. While the Main Sequence is the hydrogen core fusion stage, the first stage after the Main Sequence is the hydrogen shell fusion stage of a star’s life. During the hydrogen shell fusion stage, the nuclear fusion rate is considerably greater than during the Main Sequence. Changes in the outer layers of a star occur as the internal changes are happening. Increased pressure causes enormous expansion in the outer layers of the star, which leads to them cooling because they are farther away from the core. Visible

Indecent bodies like the sun. Stars are made up of big exploding balls of gas, mostly hydrogen and helium. The sun is similarly a star made up of huge amounts of hydrogen, undergoing a continuous nuclear reaction like a hydrogen bomb. Stars come about when vast clouds of hydrogen, helium and dust contract and collapse due to gravity. The clouds came from astronomical plasma from “The Big Bang”, but the dust comes from the supernovae of other stars.