5 Numerical Fun Facts About Pluto

How far away is Pluto? How many years does it take to fly there? How long does Pluto take to orbit the Sun? How fast is it traveling? And how fast is the New Horizons spacecraft on its way to Pluto traveling? Keep on reading to find out!

Jason Marshall, PhD
5-minute read
Episode #247

Pluto and New HorizonsJuly 14, 2015 is shaping up to be a very exciting day here on Earth. Because, of course, it’s Bastille Day! But although that will be lots of fun for many people, it’s not the real reason for my exuberance. That instead stems from the fact that on that day, I and the rest of the science-loving world will be glued to the Internet watching humanity’s first close encounter with the famous former planet Pluto.

This mission to such a distant world is truly incredible. And there are a ton of incredible numerical fun fact questions about the mission and the dwarf planet, too. For example, how far away is Pluto from Earth? How long does it take us to get there? How many years does it take Pluto to orbit the Sun? How fast is it moving in its orbit? And how fast is the New Horizons spacecraft moving? Those questions—and their numerical fun facts answers—are exactly what we’ll be talking about today.

Fact #1: How Far Away Is Pluto?

As you probably know, Pluto is no longer considered to be the ninth planet of our solar system. And contrary to what a lot of people think, I think Pluto is rather happy about that. Because instead of being the smallest regular old planet, Pluto is now classified as one of the largest dwarf planets. Pretty cool for Pluto, right? Truthfully, that whole classification thing doesn’t really matter much. Pluto is still Pluto, which means it’s still a fascinating place way out in the boonies of our solar system.

Pluto is currently about 32 times as far away from Earth as Earth is from the Sun.

Which leads us to our first numerical fun fact for today: Pluto is currently about 32 times as far away from Earth as Earth is from the Sun. As it turns out, Pluto’s orbit is much more elliptical than the nearly circular orbits of the solar system’s eight regular planets (which is one of the many ways that Pluto sticks out in the crowd). As a result, Pluto's distance from the Sun changes significantly over the course of its orbit—from about 30 times the typical Earth-Sun distance up to about 50 times this distance. Or, in more familiar Earthly units, from about 2.75 billion miles up to about 4.5 billion miles. So, yeah, Pluto is indeed way out there in the boonies.

Fact #2: How Long Does Is Take to Fly to Pluto?

Given how far away Pluto is from Earth, you might imagine that it takes a long time to get there. And your imagining would be spot on. No matter what your mode of transportation, the journey from Earth to Pluto is a long one. Even for light (which moves faster than anything else), the trip is no picnic. In fact, it takes light almost 4.5 hours to complete the journey! Since radio waves are a form of light, this means that it takes about 4.5 hours for any communications to be sent to or from the New Horizons spacecraft that's on its way to the dwarf planet.

Speaking of this spacecraft, it was launched to Pluto on January 19, 2006 (back when Pluto was still classified as a regular planet) atop an Atlas V rocket. This rocket hurtled the New Horizons probe into space with a higher speed than anything else ever launched in human history. And yet because Pluto is so far away, it has still taken nearly a decade for New Horizons to complete its journey. For comparison, if we instead had to make the journey at the typical cruising speed of a passenger aircraft (about 550 miles per hour), it would have taken about 6 centuries to make the trip.


About the Author

Jason Marshall, PhD

Jason Marshall is the author of The Math Dude's Quick and Dirty Guide to Algebra. He provides clear explanations of math terms and principles, and his simple tricks for solving basic algebra problems will have even the most math-phobic person looking forward to working out whatever math problem comes their way.