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Our
Solar System consists of the Sun and the eight planets, their moons, dwarf
planets, asteroids, Kuiper belt objects, Oort Cloud, comets, meteoroids and
interplanetary dust.
Facts about Our Solar System
The
regions of the Solar System consist of:
1. Our
Sun
2. Four Terrestrial Inner Planets: Mercury, Venus, Earth, Mars
3. Asteroid Belt: Composed of small rocky bodies
4. Four Gas Giant Outer Planets: Jupiter, Saturn, Uranus, Neptune
5.
Kuiper belt - Second belt composed of icy objects.
6. Oort cloud:
Beyond the Kuiper belt
Note: Pluto was demoted in 2006 from a Planet to
Dwarf Planet.
How does the Solar System work?
The Sun is the centre of our solar system and
celestial bodies such as the planets, their moons, the asteroid
belt, comets and other objects revolve around the Sun and
are gravitationally
bound to it. The Sun contains around 98% of all the
material in the Solar System.
The boundaries of the solar system's known
planets fit within a sphere 50 AU in radius. Beyond that is the
Oort Cloud which extends to a distance of 100,000 AU. Beyond
that is the nearest star system is Alpha Centauri.
Note: The stars
are not part of our solar system. Astronomers have discovered
that some other stars, besides our own sun, have their own solar
systems around them as well!
Sun
Our Sun is the largest object in our solar system. It is 4.6
billion years old.
Asteroids
Asteroids are small rocky objects orbiting the sun. They
range in size from nearly 1,000 km (600 miles) across to dust
particles. They are too small to be considered planets. Most are
found in the Asteroid Belt. Asteroids are also called minor
planets or planetoids.
Comets
Comets are made of ice, frozen gas, dust and rocks. Most
comets travel in highly elliptical orbits around the Sun. Most
comets are located in the Oort Cloud.
Meteoroids
Meteoroids are little chunks of rock and debris in space. The
size ranges from a grain of sand up to a boulder. They become
meteors (shooting stars) when they fall through a planet's
atmosphere. When they hit the ground are meteorites.
What is a Planet?
The International Astronomical Union (IAU) said that the definition for a
planet is now officially known as "a celestial body that:
(a) is in orbit around the Sun
(b) has sufficient mass for its self-gravity to overcome rigid body
forces so that it assumes a hydrostatic equilibrium (nearly round) shape and
(c)
has cleared the neighborhood around its orbit."
At the same time, new moons are
also being discovered, both around existing planets and within these mysterious
new worlds. Once the existence of a moon is confirmed and its orbit determined,
the moon is given a final name by the International Astronomical Union (IAU),
the organization that assumed this task since 1919.
The planets all revolve around the Sun. Six
of the eight planets are orbited by natural satellites (moons) after Earth's
Moon and each of the outer planets is encircled by planetary rings of dust and
other particles. All the planets except Earth are named after gods and goddesses
from Greco-Roman mythology. The three dwarf planets are Pluto, the largest known
Kuiper belt object; Ceres, the largest object in the asteroid belt and Eris,
which lies in the scattered disc.
Planets in the Solar System:
In order
of their distances from the Sun, the planets are:
1.
Mercury
2. Venus
3. Earth
4. Mars
5. Jupiter
6. Saturn
7. Uranus
8. Neptune.
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Did you know?
Test your knowledge with our Solar System Quiz.
There are many wonderful
Solar System Pictures
online.
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Solar System
Links:
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The Nine Planets Solar System Tour: Information about each planet and moon
in our solar system with many pictures, discussion of the history of its
discovery and exploration
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The Virtual Solar
System: Visit the Datastore for detailed facts and figures on the planets
and moons in our Solar System. Get interactive! Fly through a 3D Virtual Solar
System
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Views of
the Solar System: Views of the Solar System presents a multimedia
adventure unfolding the splendor of the Sun, planets, moons, comets and
asteroids.
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Solar
System: Learn about our Solar System with KidsAstronomy.com.
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NASA - JPL Solar System
Simulator: Online software that generates views of the bodies of our
planetary system at any date from any artificial or natural point of
observation.
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Build a Solar System: Make a scale model of the solar system with this
JavaScript enabled page. All you have to do is specify the size of the sun and
the rest is figured out.
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Solar System Model:
References:
Any
comments or suggestions, then click on Contact
Info.
Thank you for
visiting Space Projects and Info.
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