While moving to Pluto would cause drastic “weight loss”…

…it won’t do a thing for your mass.

The science museum where I work (<3!) has a scale that displays how much you would weigh on various astronomical bodies. I was standing nearby when a family from the UK stepped on, and one of the mothers expressed mild dismay that the display didn’t show both pounds and kilograms. I just had to jumpĀ in.

The display would be very uninformative if it displayed kilograms, as the number would be the same for every single planet. While pounds are a unit of force (like the Newton), kilograms are a measure of mass, not weight.

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The science of physical attraction

First off, this post is probably not about what you think it’s about.

Second off, even if you are alone on Valentine’s Day, take comfort in the fact that it doesn’t mean that no one is attracted to you. In fact, everyone is attracted to you! Every THING is attracted to you.

Gravitationally, that is.

We’re used to defining gravity as the force that holds us down on Earth, but there’s actually a gravitational force between any two objects that have mass. There’s an attractive force between you and Earth, you and the moon, you and your good-looking neighbor…so why are we always pulled toward Earth and not our neighbors?

The answer can be explained mathematically.


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