Which Planet Moves the Slowest Along Its Orbital Path?

Each planet in the solar system travels at a different speed.
••• Comstock Images/Stockbyte/Getty Images

The time it takes a planet to complete one full orbit around the sun is, by definition, one year relative to that planet. However, this answer wouldn't mean much to us earthlings, so this measurement is instead expressed relative to Earth. By using the comparable measurement of Earth years, along with the orbital distance, you can determine which planet travels slowest along its orbital path.

Longest Orbital Time

At 248 Earth years, Pluto has the longest orbital time. However, Pluto lost its planet status in 2003 when the discovery of the object Eris forced scientists to redefine what constitutes a planet. Now, Pluto is considered a "plutoid," which is a dwarf planet that orbits the sun and exists beyond Neptune. Because Pluto isn't technically a planet anymore, the longest orbital time award goes to the runner-up Neptune, with an orbital time of nearly 165 Earth years.

Slowest Orbital Speed

By dividing the distance traveled in one full orbital cycle by the orbital time, you can derive the orbital speed. If Pluto had maintained its planet status, it would have the slowest orbital speed at just 10,438 miles per hour. Instead, Neptune again wins with an orbital speed of 12,148 miles per hour. Compared to Earth's 66,621 miles per hour, Neptune is practically sluggish.

Related Articles

Why Does the Earth Rotate?
What Are the Elements of Uranus?
How Much Time Is One Day on Mars?
Distances Between the Planets in the Milky Way
What Types of Measurements Are Used for Measuring in...
What is the Distance From Saturn to the Sun?
What Is Mercury's Rotation Period?
How to Convert the Julian Date to a Calender Date
How to Calculate a Planet's Revolution Around the Sun
Orbital Radius vs. Planetary Radius
How Many Earth Days Equals One Year on Venus?
What Is the Length of Orbit & Revolution of the Planet...
What Is the Shape of Earth's Orbit?
Facts About Neptune for a School Project
What Is Venus's Revolution Period in Earth Days?
How to Convert XY Coordinates to Longitude and Latitude
Eccentricity of Planet Mars' Orbit
Movements of the Sun, Moon & Earth
Distances of the Planets From the Sun in Light Years
How Does the Earth's Revolution Affect Its Seasons?

Dont Go!

We Have More Great Sciencing Articles!