So, this time around, I thought it would be a great idea to look at 10 things you might find interesting about Pluto itself.
1. Pluto was discovered on February 18th 1930 by Clyde W Tombaugh in what is now known as the Kyper Belt.
What is the Kyper Belt? It’s the region of our Solar System that extends out from Neptune, (the 8th planet), for a distance of 30AU. (A long, long way). In fact, if you tried to drive there, you would die of old age before you’d cover a fraction of the distance!
2. Remember, although scientists originally thought they had discovered the 9th planet of our Solar System, they were wrong! In 2006, the International Astronomical Union reclassified Pluto as a dwarf planet. So, that means our Solar System has only 8 real planets, as shown above.
(Simply put, a dwarf planet is an object that has enough mass to form a sphere of material, and which orbits the sun. However, because it’s not strong or dense enough to clear other material away from its path, it has to share its orbit with other objects.)
Although Pluto was downgraded to a dwarf planet, it’s still an important member of our solar system. Why? Because she’s odd in a number of different ways.
Let’s take a look at some of them now.
3. Did you know, Pluto has a very strange orbit?
Just look at the next picture.
At its nearest, Pluto is about 4.4 billion km (2.7 billion miles) from the sun. At its farthest, 7.8 billion km (4.5 billion miles). That means, for part of its journey, Pluto is actually closer to the sun that Neptune. Wow!
Thankfully, because Pluto orbits at an angle (inclination) of 17 degrees, there’s no danger of a crash!
4. Pluto orbits the sun once every 90,465 days, that’s nearly 248 Earth years! That means, if you could be born as a Plutonian, we’d all be babies forever, because no one would ever reach their 1st birthday! (Except perhaps my neighbour – Mrs Cooper! She looks really old).
5. For some reason, Pluto’s orbit means her year is exactly 1 ½ times longer that Neptune!
6. Because Pluto is so far away, it’s difficult to find out a lot of details about her. But, we think she is composed of 70% rock and 30% ice (as a combination of water ice, nitrogen ice and solid methane, ethane and carbon monoxide). Not a very nice place to live, eh?
7. Do you realize how tiny Pluto is?
Let’s start by remembering something about the world we live on. At the equator, the Earth has a diameter is 12,756 km (7,926 miles). Not very big, but large enough for us all to live on.
Our closest neighbour in the sky is the Moon. Our Moon looks huge because she is so close to us, but, she has a diameter of just 3474 km (2159 miles). Much smaller than the Earth’s! (But still enough to fill the sky, eh?)
So, thinking about that, have a guess at how big Pluto is?
Well, Pluto’s diameter is only 2324 km (1444 miles)
Yes – she’s tiny! But do you know how tiny?
Look at the next picture then.
8. Do you realize what this means? It means, our own Moon is bigger than something that is classed as a dwarf planet. In fact, Pluto is smaller than 7 of the Solar System’s moons: Europa, Io, Ganymede, Callisto, Titan, Triton and our own Moon of course!
9. Even though Pluto is tiny, we know she has at least 3 moons of her own. Charon, Nix and Hydra. And scientists are sure that one day, as telescopes get better, we’ll find even more.
10. This is what the Sun would look like from the surface of Pluto.
Yes, the Sun is the little dot in the top, right-hand corner. If you stood on the surface of Pluto, how long do you think it would take the light from the Sun to reach you?
(Remember, Pluto’s orbit is egg shaped). So, depending where you were along that orbit, the Sun’s light would take between 4 hours and just under 7 hours to reach you!
Do you think you’d get a suntan?
Would you like to try?
So, there you go. We’ve looked at 10 interesting things about one of the smallest members of our Solar System, Pluto. Next time, I think it will be a great idea to look at 10 interesting things about the biggest member, the Sun. (But you’d better bring your sunglasses for that).
See you all next time