At the centre of our solar system is the enormous sphere of burning gasses we call the sun. The sun is far bigger (by about 1000 times) than all of the planets in the solar system put together. The Earth, and all the other planets, are subject to the gravitational pull of the sun, and orbit around it.
The Order of the Planets
The four planets closest to the sun are known as the inner planets. The four planets further away are the outer planets. Near the edge of the solar system is Pluto, which was re-classified as a minor planet in 2006, and is no longer routinely used on planetary models of the solar system. This is the order of the planets, starting with the nearest to the sun:
- Mercury
- Venus
- Earth
- Mars
- Jupiter
- Saturn
- Uranus
- Neptune
Mnemonics for the Planets in Order
There are several mnemonics used to help remember the order the planets orbit the sun. A popular one (when Pluto was still a planet) used to be:
- My (Mercury)
- Very (Venus)
- Easy (Earth)
- Method (Mars)
- Just (Jupiter)
- Simplifies (Saturn)
- Us (Uranus)
- Naming (Neptune)
- Planets (Pluto)
It’s a good one because the word My has both the first and last letters of Mercury, which helps people remember that’s what the first M stands for. Another mnemonic in wide usage was:
- My
- Very
- Excellent
- Mother
- Just
- Sent
- Us
- Nine
- Pizzas
Again, this has advantages because it's silly (silly things are usually easier to remember) and the word Mother can be shortened to Ma - a handy reminder that M stands for Mars. On a similar note, thinking about how a mars bar melts in the sun can help sort the 'M's out. Remember, never put a mars bar (Mars) next to the sun.
This similar mnemonic takes account of Pluto’s new status:
- My
- Very
- Educated
- Mother
- Just
- Said
- Uh-oh
- No
- Pluto
Is Pluto a Planet?
Pluto is still a subject of great debate, but it was downgraded to its current status as a dwarf planet because (amongst other reasons) it is so much smaller than the other major planets. It more accurately fits in the category of dwarf planet, alongside other dwarfs such as Ceres. Pluto is still affected by the gravitational pull of the sun, but its orbit is not the same as the circular orbit of the 8 major planets. It orbits in an elliptical fashion, and at a different angle. Pluto is 3674.58 million miles away from the sun, and it takes 248 years to orbit.
How Many Planets in the Milky Way
Our solar system is located in a galaxy - the Milky Way. There could be billions of other planets in the Milky Way, circling stars like our sun. Over 300 planets have already been discovered outside the solar system (extrasolar planets). Scientists at places like NASA are searching the skies with projects such as Kepler - a search for habitable planets.
Interesting Facts About the Major Planets of the Solar System
- Mars is home to many volcanoes, including the largest known in the solar system Olympus Mons, which is three times the size of Everest
- Jupiter rotates faster than any of the other planets at 28,300 miles per hour
- Venus is the hottest of the planets (it can reach 462°C), because it’s covered in clouds of gas that trap the sun's heat. It also rotates on its axis in the opposite direction to all the other planets
- Apart from the Earth, all the planets are named after Roman gods
Sources used for fact checking this article: UniverseToday.com & The Book of Time and Space by Norris McWhirter
Michelle Strozykowski - Michelle Strozykowski lives in a small brewing town smack bang in the middle of England. She loves films, especially arty European ones ...
