Stars Essay Research Paper Star BirthOur lives

Stars Essay, Research Paper

Star Birth

Our lives are intimately linked to the stars, but in ways much more down to

earth than the romantic views of them. As we all know, our sun is a star and the

thermonuclear reactions that are continuously taking place inside it are what

provide and sustain life on our planet. What do we get from the sun. We get

carbon, oxygen, calcium and iron, courtesy of stars that disappeared billions of

years ago (Naeye, 1998). Star formation is a study in contradictions because the

formation of a star begins with atoms and molecules floating freely through space

that are brought together through gravity to form masses that become stars. Stars

go through three major stages of development in their transformation from infancy

to adult stars: a collection of dust and gases, protostar, full-blown star. Pictures of

these various stages are mind-boggling in their beauty and bring one to an

immense sense of awe at the machinations of the universe. Scientists believe that

stars begin as a collection of interstellar dust and gases (Frank, 1996). This mass of

dust and gases forms a cloud that begins shrinking and rotating until it eventually

develops into what is called a protostar. Once the protostar reaches sufficient

mass, it then begins the process of converting hydrogen to helium through a series

of nuclear reactions, or nuclear fusion until it becomes a full-blown star

(Astronomy, 1995). Those protostars that are too small to complete the nuclear

fusion die out to become what are known as brown dwarfs (refer to photo at right).

Thanks to an image from the Mt. Palomar observatory, astronomers have obtained

the first image of a brown dwarf, named Gliese 229B (or GL229B). It is a small

companion to the red star, Gliese 229, which is approximately 19 light-years from

Earth in the constellation Lepus. GL229B is too hot and massive to be classified as

a planet, yet at the same time it is too small and cool to be able to shine like a

typical star .in fact, it is actually at least 100,000 times dimmer than our own sun

and is the faintest object ever to be discovered orbiting another star.

As a star forms, it is this .fusion-powered heat and radiation. emanating from the

core of the star which keeps the star whole (Watery Nurseries, 1997). If it weren.t

for this, the star would actually collapse under the stress of its own weight.

However there is a balancing act that takes place within the star between radiation

and gravity (which provides fuel for the star) that prevents this and makes it

possible for star to have a life span of billions of years. The big question, though,

is how does this whole process get started and what actually makes it

possible for these masses meld together to form a star, instead of just exploding

back into cosmic particles. What actually happens is that the clouds of gas and

dust are actually drawn into compaction through self-created gravitational collapse.

As the picture at left (from the Hubble Telescope) shows, these clouds go through

continuous implosion to become solid masses. Scientifically speaking, it is logical

to assume that this implosion should actually generate so much heat that the gas

and dust expand, rather than come together and yet this is not the case.

The reason why, scientists believe, is due to water molecules that are formed

during this process. It is the addition of these charged molecules, called

hydronium, that they believe provide the ingredient necessary to prevent further

expansion of the gasses and dust, thereby allowing the continuance of implosion

until the star finally forms a solid mass. Hydronium is made up of three hydrogen

atoms and one oxygen ion. In theory, it has the ability to transform into water

(H2O) plus one independent hydrogen atom, as long as it is able to capture a free-

floating electron from somewhere. It takes hundreds of millions of years for the

particles of dust and gas to come together into these gigantic clouds that can span

hundreds of light-years in size. The clouds are dominated by their two prime

elements of hydrogen and helium while particles of dust make up about one

percent of a cloud.s mass. In addition, there are other molecules present that

contribute to the molecular structure of the cloud, such as ammonia and other

carbon-based elements. Each cloud contains enough elements to create

approximately ten thousand new stars. It takes many millennia for a collapsing gas

cloud to fragment into thousands of dense, rotating clumps of gas that will

eventually become newborn stars. The cores of these gaseous clumps are

continuously compacting more and more as their rotation becomes faster and faster

and, over time, the cores become elongated. Some of these elongated cores are

hypothesized to eventually become binary and multiple star systems by virtue of

the fact that the cloud is stretched

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