What Is The Mass Of The Moon Compared To Earth?

The mass of the moon is about 1.2% of Earth’s mass. COMPARE.EDU.VN offers comprehensive comparisons to understand the relationship between these celestial bodies. Explore the lunar-terrestrial mass ratio and the size disparity, including insights into gravity and density contrasts, which will help you make informed comparisons.

1. Understanding the Moon’s Size and Dimensions

The moon, Earth’s closest celestial neighbor, has captivated humans for millennia. However, grasping its true size and dimensions requires a closer look at the numbers.

• What is the Moon’s radius? The moon’s mean radius measures 1,079.6 miles (1,737.5 kilometers), making it significantly smaller than Earth. This size difference is a key factor in understanding other lunar characteristics.
• What is the Moon’s diameter? The diameter of the moon is 2,159.2 miles (3,475 kilometers). Visualizing this diameter helps put the moon’s size into perspective when compared to other celestial bodies.
• What is the Moon’s equatorial circumference? The moon’s equatorial circumference is 6,783.5 miles (10,917 kilometers). This measurement provides additional context for appreciating the moon’s overall scale.

2. How Does the Moon’s Size Compare to Earth?

When comparing the moon to Earth, the size difference is striking. The moon is substantially smaller, influencing many of its physical properties.

• What is the relative size of the moon to Earth? The moon is a little more than one-quarter (27 percent) the size of Earth. This ratio (1:4) is notably larger than that of most other planets and their moons in our solar system.
• How can we visualize the size difference? According to a statement from NASA, “If Earth were the size of a nickel, the moon would be about as big as a coffee bean.” This analogy helps illustrate the size disparity in an easily understandable way.
• How does the moon’s surface area compare to Earth? The moon’s surface area is approximately 14.6 million square miles (38 million square km). To provide context, this is less than the total surface area of the continent of Asia, which is 17.2 million square miles (44.5 million square km).

3. Exploring the Moon’s Mass and Density

Beyond size, mass and density are critical factors in understanding the moon’s physical properties. These characteristics also affect its gravitational pull and overall composition.

• What is the Moon’s mass? The moon’s mass is 7.35 x 10^22 kg, which is about 1.2% of Earth’s mass. This means Earth weighs approximately 81 times more than the moon.
• What is the Moon’s density? The moon’s density is 3.34 grams per cubic centimeter (3.34 g/cm3). In comparison, this is about 60% of Earth’s density, indicating compositional differences between the two bodies.
• How does the Moon’s gravity compare to Earth’s? The moon’s gravitational force is only about 16.6% of Earth’s gravity. This means that a person would weigh about six times less on the moon than on Earth. For example, a 45-kilogram person would weigh 100 lbs. on Earth but only 16.6 lbs. on the moon.

4. Understanding Lunar Gravity

Lunar gravity significantly affects how objects behave on the moon’s surface. The weaker gravitational pull has implications for everything from the height of jumps to the behavior of liquids.

• How does the low gravity affect movement on the Moon? Due to the lower gravity, a person who can jump 10 feet on Earth could jump almost 60 feet on the moon. This difference makes activities like long jump events particularly intriguing on the lunar surface.
• Does lunar gravity vary? Like most celestial bodies, the moon’s gravity varies based on its surface features. NASA’s Gravity Recovery and Interior Laboratory (GRAIL) mission mapped the moon’s gravity in unprecedented detail in 2012, providing valuable insights into these variations.
• What did the GRAIL mission reveal about lunar gravity? According to Maria Zuber of the Massachusetts Institute of Technology, the GRAIL mission revealed that the moon “wears its gravity on its sleeve.” This means that changes in the gravity field can be directly correlated with surface features such as craters, rilles, or mountains.

5. The Moon’s Density Compared to Other Moons

The moon’s density is a key characteristic that sets it apart from other moons in the solar system. Understanding its density in relation to other moons provides insights into its formation and composition.

• How does the Moon’s density rank among other moons? The moon is the second densest moon in the solar system. Jupiter’s moon Io is denser, with a density of 3.53 g/cm3.
• Why is density important? Density provides clues about the internal composition of a celestial body. Higher density generally indicates a greater proportion of heavier elements, such as iron.
• What does the Moon’s density suggest about its composition? The moon’s density suggests that it has a significant amount of dense material, but less than some other moons like Io. This information helps scientists refine their models of the moon’s formation and evolution.

6. The Moon as a Rosetta Stone

The moon’s significance extends beyond its physical characteristics; it serves as a crucial reference point for understanding the broader solar system. Its proximity and extensive study make it an invaluable resource.

• Why is the Moon considered a Rosetta Stone? According to Noah Petro, deputy project scientist for NASA’s Lunar Reconnaissance Orbiter (LRO) mission, “The moon is the Rosetta Stone by which we understand the rest of the solar system.” Its study provides a foundation for interpreting data from other celestial bodies.
• How does studying the Moon help us understand the solar system? By understanding the moon’s formation, composition, and history, scientists can draw parallels and make inferences about other planets and moons in the solar system.
• What ongoing research is focused on the Moon? Scientists continue to study the moon through various missions and analyses, seeking to uncover more details about its past and its relationship to Earth and the solar system.

7. Exploring the Size of Other Moons in the Solar System

While Earth’s moon is significant to us, it’s essential to consider how it compares to other moons in the solar system in terms of size.

• How does our Moon compare to others in the solar system? Our moon is the biggest in the solar system relative to the size of its planet, and it is the fifth-biggest overall.
• Which moon is the largest in the solar system? Jupiter’s moon Ganymede is the largest moon in the solar system.
• What are the sizes of the largest moons? Here’s a comparison of the 10 largest moons in the solar system:

8. Supermoons: When the Moon Appears Larger

Supermoons are a captivating phenomenon that highlights the variability in the moon’s apparent size due to its orbit.

• What is a supermoon? A supermoon occurs when a full moon coincides with the moon’s closest approach to Earth (perigee). During a supermoon, the moon appears about 14 percent larger and 30 percent brighter than usual.
• Why does the Moon’s distance vary? The moon’s orbit is not perfectly circular, so its distance from Earth varies. The closest point in its orbit is known as perigee, approximately 226,000 miles (363,300 km) away.
• When was the term “supermoon” first used? The term “supermoon” was first applied by astrologer Richard Nolle in 1979. The astronomical term for the phenomenon is a perigee-syzygy moon, where syzygy refers to the alignment of three celestial bodies (Sun, Moon, and Earth).

9. Understanding the Moon Illusion

The moon sometimes appears larger when it’s near the horizon. This is not due to a physical change in the moon but rather an optical illusion.

• Why does the Moon look big when rising or setting near the horizon? The apparent increase in size is an optical illusion. This effect has been observed since ancient times, but there is still no universally accepted explanation.
• What is the Moon illusion? The moon illusion, also known as the Ponzo illusion, is a trick of the brain that makes the moon appear larger when it is near the horizon.
• What are some theories explaining the Moon illusion?
  • Cloud comparison: One theory suggests that we compare the moon to clouds. We know clouds on the horizon can be very distant, so if a cloud on the horizon appears the same size as overhead clouds, we perceive it as huge. The moon receives a similar size boost in our perception.
  • Object comparison: Another theory proposes that the moon seems larger near the horizon because we can compare its size to nearby trees and other objects on Earth. Overhead, amid the vastness of space, the moon appears smaller because there are no reference points for comparison.
• How can you test if it’s an illusion? You can hold your thumb up next to the moon and compare their sizes. The moon will appear the same size relative to your thumbnail whether it is near the horizon or higher in the sky.

10. Exploring the Moon’s Orbit

The moon’s orbit is not a perfect circle, which is a key factor in understanding phenomena like supermoons.

• Why is the Moon’s orbit not a perfect circle? The orbit of the moon is not a perfect circle because of various tidal, or gravitational, forces that pull on the moon.
• What forces influence the Moon’s orbit? The gravity of the Earth, sun, and other planets in our solar system all impact the orbit of the moon, causing it to vary.
• How often does a supermoon occur? A supermoon occurs about every 414 days on average. However, the frequency can vary, as demonstrated by the three supermoons that occurred in 2016.
• When will the Moon be as close to Earth as it was in the November 2016 supermoon? The moon won’t be as close to Earth as it was during the November 2016 supermoon until November 25, 2034.

11. Resources for Further Exploration

To deepen your understanding of the moon and its characteristics, consider exploring these additional resources.

• ESA educational infographics: The European Space Agency (ESA) offers educational infographics that provide fast facts about the moon.
• Exploratorium interactive activity: The Exploratorium science museum has an interactive activity that allows you to calculate how much you would weigh on other worlds, including the moon.
• The Illusion Index: The University of Glasgow’s Illusion Index provides a large collection of illusions, including more information about the Ponzo illusion.

12. Moon Facts

Here are some additional fun facts about the moon to enhance your understanding:

• The moon’s composition includes various minerals such as pyroxene, olivine, and plagioclase feldspar.
• The far side of the moon looks different from the near side because it has significantly fewer maria (dark, basaltic plains).
• The moon is gradually moving away from Earth at a rate of about 1.5 inches (3.8 centimeters) per year.
• There is evidence of water ice in permanently shadowed craters near the moon’s poles.
• The first artificial object to reach the moon was the Soviet Union’s Luna 2 probe in 1959.

13. Implications of Lunar Exploration

Continued exploration of the moon promises to unlock even more secrets about our solar system and potentially pave the way for future space colonization.

• Scientific discoveries: Each mission to the moon provides new data and insights into its geology, history, and potential resources.
• Resource utilization: The moon may hold valuable resources, such as helium-3, rare earth elements, and water ice, that could be used for future space missions and even terrestrial applications.
• Gateway to deeper space: Establishing a permanent base on the moon could serve as a stepping stone for missions to Mars and beyond, providing a testing ground for technologies and strategies needed for long-duration space travel.

14. FAQ About the Mass of the Moon Compared to Earth

Here are some frequently asked questions about the mass of the moon compared to Earth, providing clear and concise answers.

1. What percentage of Earth’s mass is the moon’s mass?
   The moon’s mass is approximately 1.2% of Earth’s mass.
2. How many times heavier is Earth than the Moon?
   Earth is about 81 times heavier than the moon.
3. Why is there such a big difference in mass?
   The difference in mass is due to the moon’s smaller size and lower density compared to Earth.
4. Does the Moon’s mass affect Earth in any way?
   Yes, the moon’s mass and gravitational pull influence Earth’s tides and stabilize Earth’s axial tilt.
5. How does the Moon’s mass compare to other moons in the solar system?
   While our moon is relatively large compared to its planet, other moons like Ganymede and Titan have greater mass.
6. How was the mass of the Moon determined?
   The mass of the Moon was determined through gravitational measurements and observations of its orbit.
7. Is the mass of the Moon constant?
   The moon’s mass is considered constant, although it does lose a small amount of mass over billions of years due to the solar wind.
8. How does the Moon’s mass affect its gravitational pull?
   The moon’s mass directly determines its gravitational pull; a smaller mass results in weaker gravity compared to Earth.
9. What would happen if the Moon had the same mass as Earth?
   If the moon had the same mass as Earth, it would cause significant changes to Earth’s tides and potentially destabilize the planet’s axial tilt, affecting climate and seasons.
10. How does the study of the Moon’s mass help scientists?
    Studying the Moon’s mass helps scientists understand its formation, composition, and its interactions with Earth and the rest of the solar system.

15. Call to Action

Navigating the cosmos of information can be challenging, especially when comparing celestial bodies. At COMPARE.EDU.VN, we simplify complex comparisons to help you make informed decisions. Whether you’re curious about planetary masses or seeking in-depth analyses, our platform offers the insights you need.

Ready to explore more comparisons and expand your knowledge? Visit COMPARE.EDU.VN today to discover a universe of information at your fingertips. Contact us at 333 Comparison Plaza, Choice City, CA 90210, United States, or reach out via WhatsApp at +1 (626) 555-9090. Let compare.edu.vn be your guide to informed decisions!