You can think of a protostar as an immature star, starting its stellar (pertaining to stars) evolution. The development of a star begins with the nebula, a swirling cloud of interstellar (in between starts) gas and dust molecules. Because of the gravitational attraction that the molecules have, the nebula can unite into a denser, tightly packed object called a protostar through the process of accretion. The cloud becomes so dense that visible light inside it is blocked and cannot be seen.

As the protostar continues to gravitationally attract material and condenses into a more compacted form, the temperature and pressure at its center increases. When the inner temperature reaches about ten million degrees Celsius or eighteen million degrees Fahrenheit, nuclear reaction at the center of the protostar ensues. Before this occurs, the protostar is in a very unstable state. Atoms of hydrogen then bind together into helium, releasing a huge amount of energy that radiates outward as light and heat. This is the reason why stars are seen by people as being bright. At this stage, the star has attained a state of equilibrium.

This process of star formation takes approximately one hundred thousand years and even more to complete. The process of star formation is very dynamic with new stars born constantly. Learning about star formation fosters understanding of the vast and mysterious universe.

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The nebula is said to be 6,000 light years away from the earth. At its core lies an open cluster of stars. It is considered at least 40 times larger than the earth, and a hundred thousand times more radiant than the sun.

The color of the Omega nebula is reddish and at times pinkish. On the other hand, the brightest region is actually white. This is said to be a result of mixture of hot gas emissions and the light of the bright star in the region. Its nebula is heated by hidden young stars, which make up the infrared light appearance.

M17 is considered exceptionally juvenile-in astronomical terms. It is visible through the naked eye because of it apparent brightness. It is adjacent to the M16, which is the Eagle nebula.

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Outgassing

This happens in many areas, including environments, nature and other processes. However, outgassing in astronomy specifically refers to gases released by the earth and other terrestrial planets. The earth, for instance, releases gaseous products such as helium and carbon dioxide from the mantle’s magma, in the midst of crust formation.

Outgassing can be measured by comparing gas ratios in a planet’s atmosphere. In terrestial planets, several radiogenic substances are considered to be constant. Noble gas ratios can be affected by atmospherics escape processes. It is said that on earth, outgassing efficiency is at 30-70 percent. Lesser than this would translate to lesser water present in the earth’s surface.

The release of gases by volcanoes and rocks make up for the atmosphere it is today. It’s essential past, the release of greenhouse gases contributed to maintain warming of the earth, as the sun was incapable of producing much needed heat. Alongside evolution of all living things is continuous outgassing.

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If a star formation is occurring within, a Giant Molecular Cloud is also called a stellar nursery. Yes, this is where stars and suns are born. They also look like dark clouds of dust and gas, because they do not give off their own light and thus quite hard to detect. Giant Molecular Clouds are very cold, with temperatures from about 253 to -233 degrees Celsius (-450 to -380 degrees Fahrenheit or 10 to 50 degrees Kelvin).

Giant molecular clouds have a lifespan of about 10 to 100 million years before they disperse, because of the heat and stellar winds caused by the star formations within them. Our own Milky Way, contains about 2,000 Giant Molecular Clouds, plus other numerous smaller clouds.

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Not many know that it?s not just plasma TVs and plasma balls in museums which have ionized gas or plasma. When gas is ionized it specifically means gas electrons have been charged enough to let them escape atoms or molecules (positive ionization). When this happens there is always a visual manifestation no matter how slight, and they usually are spectacular to behold.

Take, for example, the inside of fluorescent lamps and neon signs, lightning, St. Elmo?s fire, and the auroras. A lot in outer space are made of plasma?the Sun, stars and solar wind, the space between stars, planets and galaxies, and nebulas. In fact it is plasma which is the most common state of matter in outer space, which only makes sense because if the stars and the space between almost everything in the universe is plasma, then that is indeed a lot of ionized gas.

Galactic Ionized Gas

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Stellar wind may be different for each type of star. Post main sequence stars that are on the final stages of their stellar evolution commonly release huge amounts of matter in massive but slow winds. Red giants, red super giants and asymptotic giant branch stars all have stellar winds in this manner. Their winds are driven by radiation pressure on dusts that are condensed in the star’s upper atmosphere. The stellar winds from main sequence stars do not affect the evolution of stars with lower mass.

The stellar winds of massive stars have lower mass loss rates; however their velocities are very high. Their winds are driven by radiation pressure centered on the resonance absorption lines of heavy elements like carbon and nitrogen. Massive stars usually produce high energy stellar wind bubbles.

Even the sun produces its own stellar wind called the solar wind that is driven by its hot and magnetized corona. The solar wind consists mainly of high energy electrons and protons that escape the sun’s gravity due to the high temperature of its corona.

Winds do not blow only in the earth’s atmosphere, winds do blow in stars and the sun too. Imagine how roasted everything could be if a stellar wind would touch you skin when you wake up one day!

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In fact, a group of astronomers and scientists have recently collaborated to understand the nature of icy sublimation in most stars and planets. Their study is centered on the presence of ice sublimates or ice which is formed from gas.

Through their study, they have determined that the icy dust particles form dust rings through the pile ups at the edges of their sublimation zones. Here they sublime substantially at temperatures from 100-110 K. The distance of the dust rings have been determined to be at 20-35 AU (astronomical units) from the central star.

It has been discovered that refractory particles known as residues of ice sublimation fill the inner disk of the stars, whereas, the outer icy dust disk exceeds the optical depth of the inner disks. These could be the reasons why there are inner holes formed inside the sublimation zones along the dust rings in the outer edges of the hole.

The icy sublimation may be the very same reasons why there are differences in the number of rings of Saturn and Jupiter, or why Uranus’ ring are fainter than Saturn’s rings. The thickness and the volume icy sublimates remaining is a result of different nuclear reactions of highly energized cosmic particles, which may also be factors to the existence of planetary and stellar rings.

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