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More about our Solar System
Scientists think that our Solar System is around 4.6 billion years old - that is 4,600,000,000 years old!
Most scientists think that it formed from a huge cloud of gas and dust. Because of a force called „gravity“ (which is very complicated to under-
stand, and much too complicated to explain here!), this cloud began to flatten out and at the middle of it the Sun began to form. 98% of all the
gas and dust in the cloud went to form the Sun.
The remaining 2% of gas and dust began to spin around our newly forming Sun and started to come together to form the 8 planets of the Solar
System.
The dust and gas also formed lots of moons that circle the planets, as well as lots of asteroids.
Asteroids are lumps of rock, just like some planets, but they are much smaller. We know of more than 10,000 asteroids in our Solar System, and
lots of them are in a cluster called „the Asteroid Belt“ that is between Mars and Jupiter. They behave just like planets, circling around the Sun.
The smallest asteroids are just a few feet wide, but the biggest are hundreds of miles across.
This model gives you an idea of what the Solar System looks like and how it behaves, but this is not a proper scale model of the Solar System.
lf we were to make a real scale model of the Solar System with the Sun the same size as it is in this model (which is 4 inches, or 10 cm, wide),
then the farthest away planet, Pluto, would have to be more than 1400 feet ( over 430 metres) away! Even the Earth would be 36 feet (11 met-
res) away!
While these distances may seem big to us humans, they are nothing compared to how huge the rest of space is.
At the centre of our Solar System is the Sun, and it is the source of all the energy that life on Earth needs. lt may look like a huge hot ball of light
to us here on Earth, but it is really just a small star.
At night, when you look up into the sky you can see more stars than you can count. Compared to most of these, our Sun is very small.
Stars also come in their own groups. Just like the planets belang to our Solar System, our star belongs to a ”galaxy“. Our galaxy is called ”the
Milky Way“, and in it are more than 100 million (100,000,000) stars!
Galaxies look like big spirals in space.
Scientists are still not sure how many stars have their own planets
revolving around them.
We know that lots of stars have no planets, and scientists have found
that some stars do have planets, but because we are looking across
such large distances it is difficult to see anything clearly.
There is so much to learn about the Solar System, and the rest of
space. lf you keep on studying, who knows - maybe you can help find
life in another Solar System!
