# Playing basketball on the moon

## Main Question or Discussion Point

If I was designing a basket ball court for the moon what exactly would i have to change in order for it to work? Like how would i change the size, make it smaller or larger? What other regulations would i need to change in order to adapt this sport to the moon?

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Hootenanny
Staff Emeritus
Gold Member
I think one should attempt one's own science project before asking for assistance...

I suggest you start by thinking about whats different on the Earth and on the moon, and change the game accordingly

As a serious answer I think you'd have to make changes as you go while actually trying to play the game on the Moon.

Some obvious things that would probably have to change would be setting the nets higher. Since, with the same effort, under 1/6 gravity you could jump 6 times higher, a "slam dunk" might be a little too easy to pull off.

(I'd expect any five year old to be able to teach M. Jordan a thing or two about "hang time" when playing on the Moon) ;-)

But, seriously, who knows?

It might be easy jumping to the height required to dunk the ball at current regulation height were you playing on the Moon, but it could also be *so* easy to "over jump", that you'd pass the net and find yourself having a hard time getting the ball to go through the hoop as it quickly recedes from beneath your toes.

Additionally it could be that just to get a ball to drop through the net it would have to be a LOT closer to a "nuthin' but net" shot. A shot that would normally roll around the rim before dropping probably WOULDN'T drop under 1/6g. It'd just bounce out for the rebound.

So, maybe you'd have to increase the diameter of the hoop as well.

"Dribbling" would become SERIOUSLY problematic I'd expect. You might have to drop the air pressure in the ball to give it quite a bit less "bounce" just to make anything vaguely similar to "dribbling" even possible.

Additionally, you wouldn't be able to move around on the court in an even vaguely similar fashion. Under 1/6 g your feet don't supply the grip needed to "run" the way you can on Earth (your feet just slip over the surface of the floor too easily without providing much forward movement). Players might be forced to sort of "bunny hop" around the court the way astronauts did on the Moon landings. Picture players "bunny hopping" across the court while trying to dribble a ball that just doesn't respond to being bounced the way it does on Earth and I think you'll get the idea.

There'd also, I'd expect, be some SERIOUS changes forced in game strategy. For example, playing on the Moon might require more of an "East Coast" game where more emphasis is placed on action in the paint than trying for three point shots. A three point jump shot would take a lot more time from release to reaching the rim, so much more time perhaps, that ANY attempt at a three pointer could be blocked before the ball made it from a player's hand to the net.

Seeing as how moving around the court would probably just flat out take more time than on Earth ('cause your shoes just don't have the same lateral grip on the floor), "Moon-ball" might require MUCH more of a passing game and vying for position as well.

Then again, maybe it'd be more fun to make NO changes to the court, or the ball, or even the rules, and see how players adapt their techniques to the new environment.

Either way I'd expect "B-ball" to be a WHOLE 'nuther animal when played on the Moon.

Last edited:
Hootenanny
Staff Emeritus
Gold Member
"Dribbling" would become SERIOUSLY problematic I'd expect. You might have to drop the air pressure in the ball to give it quite a bit less "bounce" just to make anything vaguely similar to "dribbling" even possible.
I think one would have to reduce the air pressure in the ball anyway...

First the basket ball court should be enclosed in a closed atmosphere and pressurised inside the court, since the atmospheric pressure on moon is one trillointh as of the earth's atmosphere.

I think one would have to reduce the air pressure in the ball anyway...
why?
Say the pressure inside the ball when here on Earth is normally 2 atmospheres above atmospheric (ie 28psi or 2 bar).

Take that ball to the moon, the effective pressure inside only goes up 50% to 3 atmospheres above atmospheric (ie 42psi or 3 bar). You think it would pop ?

Weight doesn't really have an effect on the grip of your feet while in contact with the ground, although you would be off the ground a lot more, so that could make it seem that way I guess.

Weight doesn't really have an effect on the grip of your feet while in contact with the ground, although you would be off the ground a lot more, so that could make it seem that way I guess.
Increasing the acceleration due to gravity g on Earth would definitely give you more grip.
(if you could do that - by making mass of earth bigger)

Likewise, reducing g by moving to the moon definitely gives you less grip.
For example, if g was zero you would have zero grip.

Increasing the acceleration due to gravity g on Earth would definitely give you more grip.
(if you could do that - by making mass of earth bigger)

Likewise, reducing g by moving to the moon definitely gives you less grip.
For example, if g was zero you would have zero grip.
You are completely right, I was neglecting that inertia stays the same (a stupid thing to do).

As noted above, 1/6g = 1/6 effective weight = 1/6 lateral grip between shoes and floor BUT having to deal with having the same mass, and inertia.

One way of getting a grip on the floor would be to use weights. A 250 pound man would weigh just a tad over 41-1/2 pounds on the Moon. If he were to wear 1250 (Earth bound) pounds of weight, on the Moon, he'd be back to weighing 250 pounds - BUT - he'd now have to deal with having the inertia of a 1500 pound guy!

Getting started from a dead stop to a down court sprint would be like trying to do it with a Chevy tied to your belt. And stopping once started - well, lets just say I'm not sure I'd really WANT "court side seats".

Which brings me to the "radical idea" part.

Life on the Moon under 1/6g - long term - would carry with it an almost uncountable number of problems large and small.

Drinking glasses would have to be taller to keep drinks from spilling, just turning a sharp corner in a hallway would be more difficult, papers would blow off desks with just a hint of a breeze from a near by air duct or someone walking by, and pluming, consider all of the differences that would have to be addressed with simple indoor pluming codes. Drainage pipes would have to run at 6 times the slope to carry things like solid waste, to develop the same head pressure a water tower or reservoir would have to be 6 times higher,...

All of which could be overcome, I'm sure, but - I'm not at all as sure that the same thing could be said about THE HEALTH IMPLICATIONS of living out your life under just 1/6g.

There's no telling WHAT kind of complications trying to carry a child to term under 1/6 g would have (and I'm not sure anyone would care to find out the hard way). Additionally, no one has any idea whether or not spending your whole life under 1/6 g could cause osteoporosis to set in nearly as quickly under 1/6 g as it apparently does in near zero g.

So...

What if, instead of trying to live under 1/6 g, housing on the Moon was designed around essentially truncated conical structures that spin in order to produce, if not a full g, some determined minimum acceleration required to promote sustainable health?

In a case like that, you could have a B-ball court set within the edge of a large spinning conical structure, where the game could be played under "normal gravity", and all you'd have to deal with is some odd effects on a ball's trajectory due to coriolis effects.

It could be that people living on the Moon, long term, would come to view spending time in low g the way many people view spending time in the Sun. You don't worry about exposure to the Sun getting from your car to the house, or walking around outside, but if you've got a brain in your head, you don't over do it. Without a shirt, or sunblock, you limit your exposure. Ditto with low g, you don't get all paranoid about it, but - if you've got a brain in your head, you don't overdo exposure to low g either.