The Solar System
Space. A dark territory of openness that
we all want to someday travel through.
How fun it would be to travel in space,
our space, our Solar System. To be able
to eventually travel to far planets, to see
rings up close, or to land on a comet as it
races across the openness of space.
The Solar System -- three small words
for a great amount of space and matter.
Our Solar System is made up of lots of
open and empty space. The largest body
or matter in our solar system is the sun.
Our sun contains 99.85% of the matter in
our Solar System. Does that seem
funny? Our sun seems small compared
to all of the empty space, stars, and other
matter we see so vibrantly at night in the
dark sky.
The beginning of our solar system is
quite simple. Our Solar System was
formed from a cloud of gas. The cloud
of gas consisted of three things -- 75% of
hydrogen, 25% helium and 1% heavier
elements. These three main elements
condensed into the gas cloud which
continued to condense into solid objects.
Those solid objects are what we know
today as our Sun and the nine planets Mercury, Venus, Earth, Mars, Jupiter,
Saturn, Uranus, Neptune, and Pluto. A
very humble beginning.
In addition to the sun and planets, our
solar system also consists of small
bodies. These small bodies are comets,
asteroids, meteoroids, satellites of the
planets, and interplanetary medium.
Interplanetary medium is considered the
gas and dust that floats around in our
solar system.
Solar System (ART 6.1)
All of this "stuff", this matter, makes up
our solar system. Below is the
breakdown by percentage of our solar
system and it's matter make-up:
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

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Sun = 99.85%
Planets = .135%
Comets = .01%
Satellites = .00005%
Minor planets = .0000002%
Meteoroids = .000001%
Interplanetary medium = .0000001%
WOW! How amazing that our sun really
contains that amount of matter. It really
is as large as it seems out there in our
sky!
OK, remember when I mentioned
everything that made up our solar
system? Do you remember the planets?
OK, our solar system is in a way divided
in to two. The two "divides" are the
inner solar system and the outer solar
system
Our "inner" solar system consists of the
Sun, Mercury, Venus, Earth, and Mars.
The four planets included in the "inner"
solar system - Mercury, Venus, Earth,
and Mars - are called the terrestrial
planets. The terrestrial planets are called
this because they have a solid, rocky
surface.
Our "outer" solar system consists of
Jupiter, Saturn, Uranus, and Neptune.
Jupiter and Saturn are called the gas
giants, while Uranus and Neptune are
called the ice giants. All of these planets
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together are known as the Jovian planets,
after the planet Jupiter.
Pluto is alone by itself just as it is in the
solar system. Although Pluto is a solid
planet like the terrestrial planets, it has
an icier surface that allows it to be all by
itself. There are other dwarf planets
besides Pluto, but their make-up is still
being determined.
The "inner and outer" solar systems are
divided by an asteroid belt. The asteroid
belt lies between the orbits of Mars and
Jupiter. It is this asteroid belt that divides
our solar system into the "inner" and
"outer" solar system. This asteroid belt is
where the majority of the asteroids in
our solar system orbit.
own place - the Asteroid Belt - comets
have their own spaces as well – the
Kuiper Belt, and the Oort Cloud.
Right dab in the middle of our solar
system is the Sun. The nine planets Mercury, Venus, Earth, Mars, Jupiter,
Saturn, Uranus, Neptune, and Pluto then orbit the Sun. When a planet orbits
the sun it basically means that the planet
goes around the sun. An orbit is also
called an ellipse. The ellipse or orbit of a
planet is also not a perfect circle. It is
more an oval.
The oval ellipse was first discovered by
German astronomer and mathematician
Johannes Kepler.
Now, to us our solar system is HUGE!
Filled with the Sun and planets, and all
the stars in the night sky, this is a lot but
we are only one of many systems that
make up an even larger body, our
galaxy, The Milky Way. And, no, that is
not the candy bar.
The Milky Way is our galaxy and our
solar system, large to us but small in the
grand scheme of things, orbits in one of
the spiral arms that make up the Milky
Way. The spiral arm the solar system is
part of is the Orion-Cygnus arm. There
are more than 200 billion more stars that
share our galaxy.
Earlier, I also mentioned comets.
Comets within our solar system lie in the
farthest part of our solar system, behind
the orbit of Pluto. As asteroids have their
Solar System (ART 6.1)
So as you can see we are just but a small
part of the large picture. From the
universe, to our galaxy, to our solar
system, to our world, Earth; who knows
how far we may be able to go tomorrow
but for now keep watching our dark sky
with bright stars.
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