Planets and Their Sizes

Part of Scales of the Universe.

Planets-and-their-sizes_HERO

Earth is nearly 13,000 kilometers across. The smallest terrestrial planet, Mercury, has a diameter about 40 percent of that size. Jupiter, the biggest planet, is more than ten times larger than Earth. The maximum possible size for a planet is a few times larger than Jupiter - about the same size as the smallest stars.

In This Section

Exhibit Mercury If the Hayden sphere is the size of the Sun, then this model is the relative size of Mercury. Exhibit Venus If the Hayden sphere is the size of the Sun, then this model is the relative size of Venus. Exhibit Earth If the Hayden sphere is the size of the Sun, then this model is the relative size of Earth. Exhibit Mars If the Hayden sphere is the size of the Sun, then this model is the relative size of Mars. Exhibit Jupiter If the Hayden sphere is the size of the Sun, then this model is the relative size of Jupiter. Exhibit Saturn If the Hayden sphere is the size of the Sun, then this model is the relative size of Saturn. Exhibit Uranus If the Hayden sphere is the size of the Sun, then this model is the relative size of Uranus. Exhibit Neptune If the Hayden sphere is the size of the Sun, then this model is the relative size of Neptune. Exhibit Janus If the Hayden Sphere is the size of Earth, then this model is the relative size of Saturn’s moon Janus. Exhibit Meteor Crater If the Hayden Sphere is the size of Saturn’s moon Janus, then this model is the relative size of Meteor Crater. Exhibit The Hayden Sphere and Humans If the Hayden Sphere is the size of Meteor Crater, then this model is the relative size of the Hayden Sphere. Exhibit Raindrop If the Hayden Sphere is the size of the human brain, then this model is the relative size of a raindrop. Exhibit Red Blood Cell If the Hayden Sphere is the size of a raindrop then this model is the relative size of a red blood cell. Exhibit Rhinovirus If the Hayden Sphere is the size of a red blood cell, then this model is the relative size of a rhinovirus.