Bad Astronomy

Q & BA Episode 4: The Gravity of the Situation

Ah, is there anything more wonderful than being locked in the warm embrace of someone you love? The emotion, the beauty of the moment, the attraction you feel… but wait! Is that pull you feel really from your Significant Other, or is it due to… the Moon?

Just how strong is the gravity from the Moon compared to someone right next to you?

Well, listen to Q & BA Episode 4: “The Gravity of the Situation” and find out!

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Show notes

The Question:

The question was sent in by Jesse C. of Doylestown, PA: “Does a person standing beside you have a greater gravitational pull on you than the Moon? I recently heard someone mention it. It sounds like a bunch of malarkey… but is it true?”

If you want to the calculations for yourself, then start with

where lower case m is your mass, upper case M is the mass of the object (the Moon, the other person, etc.), R is the distance between the two of you, and G is a constant. When you divide the force from the Moon by the force from the person, your mass and the constant divide out (your mass divided by your mass = 1). For the masses of the planets and such, go to The Nine Planets.

Images:

Mu Cephei is from Davide De Martin’s Sky Factory

Eta Carinae is from NASA/Hubble/AURA.

The Sun and Earth are from NASA (the Earth shot is from the fantabulous MESSENGER Earth flyby).

The pictures of the Flatiron/Rocky Mountains and of me fishing in Kansas are courtesy of, um, me.

And since I know people will ask: The T-shirt is available from the FSM website.

… and one more link. Guess why?