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Life Cycle of a Star – Birth through to Death The life cycle of a star is an amazing scientific phenomenon that takes billions and billions of years to occur and involves several stages each with its own interesting characteristics. Before we delve deeply into the various process involved in the creation of a star, let us first try to define what a star actually is. A start is a luminous globe of gas that is capable of producing its own heat and light through nuclear fusion. It is created from a nebula, which is a cloud of hydrogen and helium gas as well as dust existing in space. The life cycle of a star begins with the nebula. It is known as the birthplace of stars, the nebula is known to have several kinds. Basically, stars are formed from the gases that are contained within the nebula. These clouds of gases – hydrogen and helium – and dust collapse due to gravitational forces resulting to the formation of protostars. Protostars which are known as young stars eventually collapse in order to form main sequence stars or also called dwarf stars. A red dwarf star is small and faint approximately tenth of the diameter of the Sun. These burn slowly and live to about a hundred billion years. These would eventually expand as they begin to grow old; as time goes on; its core runs of hydrogen and helium gases. This results in the cooling of the star and a decrease in its brightness, this star is now known as the red giant. The red giant or can also be called the red super giant is a large bright star that has a cooler surface temperature – 2,000 to 3,000 o C. They are considered
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Facts about Star

Mar 24, 2016

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Matthew Moore

Hi, my name is Ben Ten living in North America. I am a student of Bachelors Part – II and a book wormer. I interested in astronomy and I prefer to search for information about astronomy. I want to have some necessary knowledge about astronomy. I especially draw my attention in Planet Star. I introduce my website, which contain the useful information about Star planet and some Facts about planet Star. There are also some pictures of Star. I hope that, they will provide to you useful knowledge about astronomy in general and STAR in particular.
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Page 1: Facts about Star

Life Cycle of a Star – Birth through to Death The life cycle of a star is an amazing scientific phenomenon that takes

billions and billions of years to occur and involves several stages each with its

own interesting characteristics. Before we delve deeply into the various process

involved in the creation of a star, let us first try to define what a star actually is. A

start is a luminous globe of gas that is capable of producing its own heat and light

through nuclear fusion. It is created from a nebula, which is a cloud of hydrogen

and helium gas as well as dust existing in space.

The life cycle of a star

begins with the nebula. It is

known as the birthplace of

stars, the nebula is known to

have several kinds. Basically,

stars are formed from the gases

that are contained within the

nebula. These clouds of gases

– hydrogen and helium – and

dust collapse due to

gravitational forces resulting to the formation of protostars.

Protostars which are known as young stars eventually collapse in order to

form main sequence stars or also called dwarf stars. A red dwarf star is small and

faint approximately tenth of the diameter of the Sun. These burn slowly and live to

about a hundred billion years.

These would eventually expand as they begin to grow old; as time goes on;

its core runs of hydrogen and helium gases. This results in the cooling of the star

and a decrease in its brightness, this star is now known as the red giant.

The red giant or can also be called the red super giant is a large bright star

that has a cooler surface temperature – 2,000 to 3,000oC. They are considered

Page 2: Facts about Star

bright due to their size although the core temperature is quite low. The red giant

collapses in time leading to a massive explosion known as the Supernova. The

white dwarf star is part of the last stage of the life cycle of a star after the red

giant. A perfect example of this would be the Sun.

Depending on the star’s original mass, it can have several fates:

Black dwarf

The black dwarf is

considered as a stellar

remnant that has lost its

heat due to the depletion

of the helium and

hydrogen gases from its

core. It commonly arises

from the white dwarf star.

Neutron Star

This type of star

occurs after a supernova.

It results from the

combination of protons

and electrons leading to the formation of the neutron star. According to studies, if

the mass of a neutron star further decreases, there is a possibility that the increase

in gravitational pull can result to the creation of a black hole.

Black Hole

These are believed to form from massive sized stars when their lifespan ends.

It is believed that due to the intense gravitational pull within the black hole, not

even light can escape it. The density of matter within a black hole is immeasurable

since they can distort the space surrounding them and suck in the matter nearby.

Page 3: Facts about Star

Stars – Celestial Objects On Sea and Sky For as long as mankind can remember, stars have been those celestial objects

on sea and sky that have stirred up a lot of theories with regards to what they are

and how they came to be. Constellations are known as the chance aligning of the

stars that form several various icons coming from the ancient times. These

constellations are utilized by astronomers in order to provide organization to the

skies at night and to properly

locate the stars.

Stars are considered as the

most numerous visible objects in

the universe. The light and

energy emitted by these objects

are considered as a power source

for the solar system. Also

coming from the star are the

heavy elements that are essential

components in the formation of life forms. They are a keystone piece in the

creation of life in the universe. Without them, the universe would cease to exist as

is.

A perfect example of a star that provides energy to life forms would be the

Sun. The Sun as we know, gives life to Earth through the energy and heat it

provides for all the living species on the planet. Energy and heat are essential

factors for the survival of our species against the coldness of outer space.

So it brings us to the question, does the brightness of a star have any relation

to its core temperature? The measure of the stars brightness is termed as its

magnitude and identifying the colour to determine the temperature. Astronomers

have developed a scale to determine the magnitude and temperature of a star based

on its characteristics.

Page 4: Facts about Star

For the magnitude, the lower the value of the number given, the brighter the

star is. As for the colour and temperature, stars are divided among their colour and

ranked in what is called a spectral

class. This is an array of various

stars beginning from Class O

which is blue to the Class M that

are red. The hotter and higher the

temperature of the star, the more

intense shade of blue it is. While

stars that are red in colour, fall

under the category of cooler

temperatures.

Contrary to popular belief, stars in the sky do not really twinkle. The

occurrence of the phenomenon that makes stars seem to twinkle is a direct effect

from the interference in atmosphere. Air emitted rises, which causes images we

see to wave and blur. Stars that are lower in position in the sky have more

tendencies to twinkle in comparison to those that are in a higher location.

The twinkling effects of celestial objects on sea and sky are more likely to

occur in lower located stars since more light is required to pass through the

planet’s atmosphere. A good analogy or comparison would be in the case of a hot

summer day. Upon gazing far out into the pavement, there is a tendency for the

road to blur or seem to move. It is actually the hot air escaping from the pavement

and into the atmosphere.

Stars – The Solar System and Outer Space Probably among all the famous stars within the solar system and outer

space, the most popular would have to be the sun. The sun actually comprises of

almost all the matter within the solar system, the remaining matter would be

Page 5: Facts about Star

composed of the planets Jupiter and

Saturn. Within the solar system and

outer space, there are numerous

astronomical objects that are bound to

the orbit through the force of gravity.

Stars are among the most

abundant astronomical objects that lay

within the entirety of the solar system.

Created from space formations termed

as nebula, these stars live for billions

of years as glowing structures of

burning gas. As the star ages, its core

temperature becomes cooler and the entire structure becomes unstable. The

instability of an aging star eventually leads to its death in a massive explosion

known as the supernova.

The particles and elements coming from these stars explosions are the core

ingredients that ultimately become new stars when they combine with other gases

and dust. This occurrence is a perfect example of where energy is neither

destroyed nor created. It only changes in form.

Eventually the increase of the pull of gravity forces the creation of brand new

stars. The increase in gravitational force is due to the spinning action created by

the clouds of dust, hydrogen and helium gases. These are the initial stages of the

formation of a new star.

If you wonder why stars are so bright, you can compare the mechanism of a

star to that of a nuclear reactor. A massive amount of energy is being produced by

stars through nuclear fusion involving helium and hydrogen gas molecules. This is

the source of the brightness of a star.

Surprisingly, there are about two hundred billion stars within the known

universe. That does not even include the sun! Since the sun is the nearest star to

Page 6: Facts about Star

our planet, we are able to observe its natural form as a glowing hot ball of gas.

While we look at other stars in the sky as small little dots resembling lights on a

Christmas tree. They seem tiny when in fact these stars can be as massive or even

much more in comparison to our Sun.

It is only due to their extreme

distance which makes them difficult

to see in their actual form. To give

you a better idea on how massive

another star can be, the Sun is

actually just a medium sized star.

While our planet, in terms of the

diameter is only a hundredth of that

of the Sun. So imagine another star

that is twice or more in size of the

Sun, big huh? Giant stars are about

one thousand times the diameter of the Sun. These are found in several different

galaxies that are billions of light years away.

So the next time you look up in that night sky and you see a star twinkle,

imagine how many light years it took for that light to travel. Imagine that the star

you’re looking at is only a minute part of an even bigger picture.

Interesting Facts about Stars The night sky is filled with a lot of mysteries and trivial information. There

are a lot of interesting facts about stars that you may not know of. Knowing

about these trivial facts can actually help you to appreciate the universe more or

can be an interesting topic for conversation between you and your peers. So here

are some interesting facts about stars:

1. The Sun is the closest star to Earth.

Page 7: Facts about Star

For those that don’t know, yes, the Sun is a star! It is the closest one to the

planet - approximately 150 million kilometers away. The Sun is classified under

the G2 yellow dwarf star class and is in the phase of its life cycle known as the

main sequence. Our Sun, like most other stars, emits energy and light through

conversion of hydrogen and helium atoms. This process – nuclear fusion – occurs

at the Sun’s core where it’s the hottest.

The Sun is estimated to be

about 4.5 billion years old and is

predicted to be in this phase for

another seven billion years or so.

Unfortunately, like most other stars,

when the time comes that it runs out

of fuel, it would become a red giant

star while increasing in size. There is

even a probability that it would

engulf Mercury, Venus and probably

even Earth as it expands.

2. All stars are in a perfect

state of balance.

Since they are billions of light years away, it would be difficult to know that

stars are actually in a constant battle or conflict with themselves. All the stars have

their own gravitational pull that pulls itself inward. This action, if not repelled by

another force would lead to the continuous collapse of a star until it becomes

minute in size. The amazing part is that the nuclear fusion occurring at the star’s

core actually repels the gravitational force by creating an outward push. This

phenomenon actually takes about 100,000 years to complete.

Page 8: Facts about Star

When a star loses its fuel at the core, there is no longer any action to repel the

pull of gravity hence a star collapses into smaller minute particles known as

dwarfs.

3. Everything is

equal.

With stars, the colour,

temperature and its mass

are all related. The actual

color of a star can indicate

its size and temperature.

The hottest stars are

surprisingly the smallest

ones and are blue in colour.

Their temperatures go to about 12,000 Kelvin. While the yellow coloured stars are

the medium sized ones just like the Sun. Their temperatures fall to about 6,000

Kelvin. And lastly, the coolest and biggest ones are coloured red and have

temperatures that are less than 3,500 Kelvin.

4. Stars are just like twins.

When looking at the night sky, it would seem like stars are up there all alone.

But don’t fret; these heavenly bodies actually come in pairs. These are termed

binary stars where in a set of two stars share a common center of gravity in an

orbit. In some other systems in space, stars can even come in groups of threes or

even four!