When you go to the moon is your mass the same as it is on Earth why or why not is your weight the same Why or why not?

Here, we highlight the distinction between weight and mass on the moon. We also show the proportionality between them.

The weight of an object is a force expressed in Newton (N). It is also defined as the force of gravity acting on the object. Weight must not be confused with the mass of an object which is a fundamental property of the object expressed in kilogram (kg).

Therefore, the mass of an object on the Moon remains the same as its mass on Earth. But its weight gets less because the gravity on the moon is less than on the Earth.

Click on 'Earth' or 'Moon' to simulate their respective gravities.

Click on a mass to select it.

• To distinguish between the weight (Intensity of the force in N) and the mass of a body (Fundamental property in Kg).
• To simulate the influence of the gravitational constant on the weight.

Mass is a property of matter. Every atom has mass.

The mass of an object is the sum of the masses of all atoms that make up the object. Mass is expressed in kilograms (kg).

Weight is a…

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Last update: 08 July 2020

Have you been confusing mass with weight? It's very easy to do when you're not entirely sure of how science actually defines them. Even though they're both linked, there is a basic difference. Mass is a measure of the amount of matter in an object and weight is the amount of force that gravity has on an object.

Most of you already use these two words on an almost daily basis (especially if, like me, you're conscious of your weight and spend hours agonising over how much muscle mass you built during your last visit to the gym). I've put together a fairly comprehensive description of each of them for you which, importantly, is written in layman's terms and not scientific babble.

What is mass?

Mass is a scientific measure of the amount of matter an object is made up of. No matter where you are at given moment in time, mass is constant. So, whether you're walking to the shop to stock up on groceries or bouncing around on the moon, your mass is the same. Obviously, if you're on a diet that's not the answer you want to hear but don't panic - we'll get to the all-important definition of weight shortly.

Some other key points about mass

1. Mass is indestructible. As you've seen above, no matter where you are in the universe your mass will never change
2. Mass can never be zero. What we mean by this is that everything in the universe has mass. If it didn't it simply wouldn't exist
3. Mass is not related to gravity, centrifugal force, etc and these forces have no effect whatsoever on your mass
4. Mass is commonly measured in pounds and ounces (for those in the US, or those who use the imperial system) or kilograms and grams (for those who use the metric system). We have converters between the two.

Hopefully, the descriptions above have given you a good idea of what mass really is. Don't fall into the trap of thinking that this unit of measure is not important - it is. After all, without the huge mass that makes up planet Earth we'd have no gravity - a great way to save money on fuel as you can simply float to work, but not so great when you're trying to drink your morning espresso on your way to the office.

What is weight?

Weight is a form of measurement that is dependent on gravity and, unlike mass, your weight can vary depending on where you are in the universe.

Weight is a pretty important measure not only to dieters the world over but also to the scientists and egg heads who design things like space shuttles and boats - the opposite end of the spectrum, but it's all about perspective.

But how can weight vary whilst mass has to remain constant? It's fairly simple: weight is a variable i.e. it can change based on the amount of gravitational pull an object exerts on a body. Scientists have defined weight using this equation:

Formula: Weight (W) = Mass (M) multiplied by gravitational acceleration (g). (W = mg)

Simple, right?

Some key points about weight

1. The weight of an object changes based on where it is. If you've decided to visit the moon to test out this theory then you'll find that, in a matter of hours, you will have slashed your weight by two thirds (in your face, Slimming World!)
2. Weight is a vector (a quantity that is fully described by both a magnitude and a direction) and its direction of pull is towards the centre of the planet you're stood on. What? Sorry, I did promise layman's terms: gravity, which is created by the mass of an object, moves towards the centre of the object and it is gravity that determines your, or any other object's, weight.
3. The weight of any given object can go up or down depending on the amount of gravity acting on it. More gravity - the heavier the object. Less gravity - the lighter the object.
4. Unlike mass, weight can be zero. An example of this is an astronaut floating in space - there's no gravity acting on his body and, therefore, he has no weight.
5. Weight is commonly measured in Newtons.

Mass and weight example - the moon

In the below example, we've featured an astronaut on earth and on the moon. The Moon's gravity is much less than the Earth's gravity - approximately one sixth. So, a 100 kg astronaut weighs 980N on Earth. On the Moon, the astronaut would weigh only 162.2N. However, the astronaut's mass is 100kg where-ever they are.

Weight on Earth: 100kg x 9.8m/s2 = 980N.
Weight on Moon: 100kg x 1.622 m/s2 = 162.2N.

The difference between mass and weight - clarification

Hopefully, we've cleared up any lingering doubts you may have about the whole mass vs weight debate - mass is a measure of the amount of matter in an object and weight is the amount of force that gravity has on an object. As you can see, it's not quite a clear cut topic, but do keep these points in mind and prepare to wow your friends and family with your newfound knowledge of the scientific arts.

If you want to convert between different units of mass and weight, why not use the weight conversion tool.

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Mass is the amount of matter in an object and is unchanging. Weight is the force exerted on an object by gravity and can change under some unique conditions.

It is easy to think of weight and mass as the same thing. That is because on Earth, both terms seem to imply the same concept; however, in space the concepts of mass and weight are very different. No matter where you are in the universe, your mass is always the same: mass is a measure of the amount of matter which makes up an object. Weight, however, changes because it is a measure of the force between an object and body on which an object resides (whether that body is the Earth, the Moon, Mars, et cetera). When we talk about weight on Earth, we are really speaking about how much force the Earth is currently exerting on us through gravity.

This is what differentiates mass from weight: we will have the same mass anywhere in the universe regardless of what bodies we are near. However, our weight changes depending on how strong the local force of gravity is.

Today’s Wonder of the Day was inspired by kaily. kaily Wonders, “how much would i weigh on the moon” Thanks for WONDERing with us, kaily!

People first walked on the Moon on July 20, 1969. When Buzz Aldrin and Neil Armstrong stepped out onto the surface of the Moon that day, they not only made world history — they lost weight. How is this possible?

Before we can understand weight, we must first understand gravity and mass. Gravity is a natural force that attracts objects to each other.

On Earth, gravity is the constant force pulling us toward Earth and preventing us from flying off into space like a balloon. When you step on a scale, it shows your weight as a number. This number is actually a measurement of the gravitational pull Earth has on you.

Mass is how much “stuff" you are made of. Unlike weight, your mass is the same whether you are on Earth, on Mars, on the moon, sitting in your living room, swimming in the ocean, or floating somewhere in outer space.

Someone who weighs 200 pounds has more mass than someone who weighs 100 pounds. The more mass a person has, the greater the pull of gravity on them. This is why a scale shows a higher number for a larger person.

Small celestial bodies have weaker gravitational pulls than Earth. Larger planets, such as Jupiter and Saturn, have stronger gravitational pulls, which means you'd weigh more if you visited those planets.

Since the Moon is smaller than Earth, it has a weaker gravitational pull. In fact, the Moon only has 1/6 the gravity that Earth does. This means you weigh six times less on the Moon than you do on Earth!

When the astronauts landed on the Moon in 1969, they wore space suits and carried heavy packs of equipment. Since gravity is much weaker on the Moon, everything weighed only 1/6 of its Earth-weight, and the astronauts were able to move around the Moon very easily.