How Big is the Moon?

We see the Moon almost every day, shining bright and beautiful. Some days it looks bigger and closer, the other days it seems farther away and smaller. 

How big is the Moon, exactly? 

In this article, we will guide you to understanding how large Earth’s natural satellite and the closest celestial body is.

A NASA image showing the moon alongside Earth
The Moon (Source)

How Big is the Moon Compared to Earth?

Quick Answer: The Moon has a surface area of 14.6 million square miles (38 million square km), which is 27% that of Earth’s. The Moon is also 81 times less massive than the Earth.

While it might not sound like very much, the Moon’s surface area of 14.6 million square miles (38 million square km) is greater than the total of these five massive landmasses on Earth: 

  • The European Union (1.728 million square miles)
  • China (3.705 million square miles)
  • United States (3.797 million square miles)
  • Brazil (3.288 million square miles)
  • South Africa (470,900 square miles).

Is Our Moon Big When Compared to Other Moons in the Solar System?

Quick Answer: Our Moon is the fifth largest satellite in the solar system.

Our closest celestial neighbor might seem tiny in comparison to Earth, but the Moon is in fact the biggest satellite in relation to its planet

It is also the 5th largest moon in our solar system, preceded by Jupiter’s moons Ganymede, Callisto, and Io, and Saturn’s giant moon Titan.

Pluto, too, is smaller than the Moon. The dwarf planet’s diameter of 1476.8 miles is only 70% of the diameter of our satellite

On the other hand, Mercury — the solar system’s smallest planet both in size and volume, is only 873 miles or 1,404 km bigger than the Moon.

The table below shows selected moons of planets in our solar system and how they compare in size to our Moon and Earth.

NamePlanetDiameterComparison to MoonComparison to Earth
GanymedeJupiter3274 miles or 5268 km1.5 times bigger than the moon2.41 times smaller than Earth
TitanSaturn3200 miles or 5149 km1.48 times bigger than the moon2.47 times smaller than Earth
CallistoJupiter2995 miles or 4819 km1.38 times bigger than the moon2.5 times smaller than Earth
IoJupiter2264 miles or 3643 km1.04 times bigger than the moon3.59 times smaller than Earth
MoonEarth2159 miles or 3474 kmN/A3.66 times smaller than Earth
EuropaJupiter1940 miles or 3122 km1.11 times smaller than the moon4.08 times smaller than Earth
TritonNeptune1680 miles or 2703 km1.28 times smaller than the moon4.71 times smaller than Earth
TitaniaUranus980 miles or 1577 km2.202 times smaller than the moon8.07 times smaller than Earth
RheaSaturn 949 miles or 1527 km2.27 times smaller than the moon8.34 times smaller than Earth
OberonUranus190 miles or 305 km11.3 times smaller than the moon40.3 times smaller than Earth
This image shows the moons in comparison
A visual representation on selected planets and moons (Source)

How Long Would It Take to Travel Around the Moon?

Quick Answer: It would take you 2.9 months to walk, 18.8 days to cycle, 4 days to drive, and 11.3 hours to fly around the Moon.

Sure, we know the size of the Moon. But what do the numbers exactly mean? Let’s translate the big numbers into understandable figures. 

The following times are all based on non-stop measurements. The mentioned speeds are theoretical, referenced from human speeds on Earth.

  • Time taken to walk around the Moon (3.1 mph): 2188 hours / 91 days / 2.99 months
  • Time taken to cycle around the Moon (15 mph): 452.2 hours / 18.8 days
  • Time taken to drive around the Moon (70 mph): 96.9 hours / 4 days
  • Time taken to fly around the Moon (600 mph): 11.3 hours

How Many Moons Would Fit Inside the Earth?

Quick Answer: About 50 Moons can fit inside the Earth.

One of the easier ways to understand astronomical sizes of celestial objects is to calculate how many of one fits into the other. 

We do that by working out the volume of the two spheres by taking their diameter and using the formula 4/3·π·r3.

Our planet‘s diameter measures 12,742 km through its center. The Moon’s diameter is 3,474 km, just a little short of the width of the United States. 

The volume of Earth (using the formula 4/3·π·r3) = 1,083,206,916,846 cubic km

The volume of Moon (using the formula 4/3·π·r3) = 21,952,706,175 cubic km

1,083,206,916,846 / 21,952,706,175 = 49.343

This all means that if we assume both our planet and the Moon to be perfect hollow spheres, the ratio of their volumes is 49.343, i.e. Earth’s volume is 49.3 times that of the Moon’s.

Thus, we can fit 49 Moons inside our planet! 

Another way of tackling the question is to ask how much more surface area the Earth has than the Moon.

We work out the surface area of a sphere using the formula 4πr².

This tells us the surface area of the Moon is 37,914,863 km² and that of the Earth is 510,064,472 km².

Working out the ratio between the two gives us 509,805,891 / 37,895,642 = 13.5. So Earth has 13.5 times as much surface area than the Moon (assuming they are both flat and perfect spheres).

How Much Does the Moon Weigh?

Quick Answer: The mass of the Moon is just 1.2% of Earth’s mass.

Like other moons, Earth’s Moon is in freefall around its planet — Earth, so it experiences zero gravity. This also means that the Moon does not weigh much. 

Its mass, however, is 7.34 x 10²² kg, which is about 1.2% of Earth’s mass.

Its density, on the other hand, is 3.3 g/cm³, which is nearly 60% of Earth’s density.

How Much Do I Weigh on the Moon?

Quick Answer: You will weigh 1/6th of what you weigh on Earth.

The weight of any object — you, in this case, is the force that the planet or moon’s gravity is exerting on it. You will weigh less on the Moon because its gravitational force is weaker than Earth’s. 

To find out exactly how much you weigh, remember that the Moon’s gravity is 1/6th of Earth’s

So if you weigh 65 kg on Earth, you will weigh 65/6 = 10.75 kg on the Moon.

How High Could I Jump on the Moon?

Quick Answer: The Moon’s gravity is 1/6th of Earth’s which means you can jump 6 times higher on the Moon’s surface. The highest jump, which made it to a world record, is 2.45m on Earth, which is 14.7 m on the Moon.

The Moon’s gravity is just one-sixth that of Earth’s, so you can jump six times higher on our satellite than you can on Earth. Each time you jump, you can stay in the air for about 4 seconds before surrendering to gravity. 

The high jump record would become 14.70m on the Moon (12.54m for women). The record standing jump of 1.616m (see the video, below) would become 9.70m on the Moon.

Summary

The Moon sometimes seems small in our skies, but it is the fifth biggest moon in our solar system. 

The longest time it’ll take to travel around the Moon is to walk, for which you will need 2.9 months. If you have the technology to fly, you can tour the Moon in just 11 hours!

But we aren’t there yet, so for now we’ll enjoy its magnificent presence in our sky. 

Improve your moon observing skills, with our Guide to The Lunar 100

If any questions come to your mind as you read this article or watch the Moon, let us know and we’ll update this page.