GeoMag

T H E L AY E R S 0 F T H E U N I V E R S E

Uranus, Neptune) orbit the Sun. But it’s not just the planets and the sun that form the layers in the solar system, there are moons, asteroids, dwarf planets, and much more. Like Earth, some planets have one moon, whereas others have nearly 80! Jupiter is a much larger planet than Earth which means it has a stronger gravitational pull, therefore has the ability to pull in more objects to its orbit which explains its numerous moons. The main asteroid belt is situated between Mars and Jupiter. It contains around 1.7 million asteroids that are larger than 0.6 kilometers in diameter, and millions more smaller ones. There is also an asteroid belt beyond Neptune, called the Kuiper Belt, with about 100 million small asteroids orbiting the sun from a distance. The following criteria is required to be classified as a planet: star orbiting, spherical shape, large enough to clear other orbiting objects of a similar size. If a planet does not meet one of these three criteria, it is classified as a dwarf planet. There are five dwarf planets in the solar system, including Pluto which failed to be large enough to clear other orbiting objects of a similar size. Galaxies We live in the Milky Way. The Milky Way galaxy contains of tens of billions of solar systems, just like ours. The closest galaxy to us is the Andromeda Galaxy, even though it is almost 2.5 million light years away. If you want to know how long that is, it takes around 37,000 years to travel one light year, so I will let you do the maths! At the center of galaxies are usually black holes. Black holes are mysterious objects, and we know very little about them. The nearest is 1,500 light years away. But what we do know is that their gravitational pull is so strong that not even light can escape. They are usually formed when a huge star collapses upon itself. There are around 2 trillion galaxies and 1 billion trillion stars in the observable universe, so probably trillions of trillions more beyond what we cannot see.

The Universe The universe us everything we know and everything we do not! It contains all the wonders stated. The size of the universe defies the imagination, however big you think it is, it is probably bigger. The universe is so big, I can’t include all of it in this article. I can guarantee you that, if you were to research a little deeper, you would find hundreds of other amazing phenomena, like Hot Jupiters, or the Butterfly Nebula, or even more about the Big Bang!

THE LAYERS OUNF I TVHE ERSE

Northern Lights Manas Mapara

06 | Geographical Magazine • Merchant Taylors’ School