2328: Space Basketball

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Space Basketball
My shooting will improve over the short term, but over the long term the universe will take more shots.
Title text: My shooting will improve over the short term, but over the long term the universe will take more shots.


This is another comic in Randall's My Hobby series, released during the same week as his last hobby comic, 2326: Five Word Jargon.

Randall wishes to play basketball against outer space, hence the title Space Basketball. (His previous attempt at creating a "New Sports System" for multiplayer socially-distant basketball was not very successful.) His goal is to make thirty baskets in a row before the universe puts a meteor through his hoop.

It should be noted that while may be technically correct to call the falling space object in this case a "meteor", when it hits the ground moments later it would be known as a meteorite. See also Terminology section below. See also 1405: Meteor, for what Randall's thoughts are on this.

Randall estimates that his success rate at free-throw shooting is approximately 30%. Therefore, the chances of Cueball making 30 shots in a row is 0.330, or about 1 in five quadrillion (2×10−16); for comparison, there are approximately 150 quadrillion seconds remaining before the Sun engulfs the earth (5 billion years), so if Randall has a chute set up under the basket and enough basketballs to sustain a constant high rate of shooting, he has "decent" odds of achieving his goal before the Sun burns out. But really, Randall has comparably rapid learning at this task, whereas asteroids have extreme persistence far beyond Randall's life, so when he says the odds are comparable he is abstractly weighing his unique skillset against that of small stellar bodies. Still, the lifetime odds of being killed by a meteorite have been estimated at 1 in 75,000 or 600,000 or 700,000 [1]. These calculations are usually based on the probability of being alive at a time when a huge impact kills billions of people. Randall just uses the chance of one meteorite shot on Earth hitting this hoop (hoop-area divided by Earth-area = 3.2×10−16) which is in the same range as 0.330. Actual meteorite fall statistics report an average of 1.2 meteorites per year hitting the European continent which suggests that the average probability of Cueball winning after each shot attempt is about equivalent to a meteorite passing through the hoop over the period of 10 hours. Therefore Cueball has a better chance of winning than the universe "on the short term" if he makes more than 840 free-shot attempts per year for the rest of his life. The expected time for the universe to actually "complete" the challenge would be in the range of 8 billion years, the same magnitude to the current age of the universe and longer than the estimated remaining lifetime of the solar system.

In the title text, Randall assumes that he would get better at free throwing shooting with practice in his lifetime ("the short term"). Some of the world's best basketball players have free-throw percentages over 90%, and even professional players with reputations of being "poor" free-throw shooters (e.g. Shaquille O'Neal) are above 50%. If Randall can improve his percentage to 50%, his odds of sinking thirty baskets in a row improve to "nearly" one-in-a-billion, while a member of the elite 50–40–90 club would have a probability better than four percent of making thirty free-throws in a row. Some specialists have achieved much higher success rates, with the record for most consecutive baskets being held by Tom Amberry with 2,750. The NBA regular season record is 97 free throws in a row, set by Micheal Williams in 1993 (during the 1992–93 and 1993 94 seasons).

However, he acknowledges that in "the long term" (the life of the universe, or at least the Earth), the Earth will be hit by very many meteorites; even though it is more likely that Randall will make his thirty free-throws before a meteor passes through his basket, he does not possess the cosmic lifespan[citation needed] required to surmount the odds against him and actually have a good probability to witness either event.


A piece of space debris falling through the atmosphere is a meteor. A piece of space debris that makes it all the way to the surface of the Earth (or any planet) is a meteorite. Most meteors burn up completely and do not become meteorites.

The concept of a meteor passing through a basketball hoop, ten feet or less from hitting the ground, is so uncommonly discussed that the terminology could be a matter of some debate. Unless it is very large, a meteor this close to the ground will have slowed to terminal velocity and will no longer be burning up[citation needed]; it will therefore not be incandescing like a conventional meteor, and it is certain that it will become an actual meteorite within just a moment.

(Any meteor still incandescing within 10 feet of the ground, on the other hand, would presumably destroy both the basketball hoop and any nearby observer, meaning that poor Cueball, if still shooting, would lose the game in a much bigger way.)

Many scientifically-aware people have the habit of correcting "meteor" to "meteorite," so it may be safest to use the latter term among nerds other than Randall, or you could out-nerd them by pedantically pointing out a reason to still call it a meteor.


[Cueball, holding a basketball in front of him in both hands, is looking up at the basketball hoop in front of him. The hoop is on a standard board, but at the foot of the rod holding the hoop, there seems to be growing grass up, indicating it is outside.]
Cueball: Okay, here are the rules:
Cueball: I have to make 30 shots in a row before a meteor falls through the hoop.
Cueball: I'm a 30% free throw shooter so the odds are actually pretty even.
Cueball: Ready...Go!
[Caption below panel:]
My hobby: playing basketball against space

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I don't understand why there's any debate about the terminology. He is specifically talking about something that "falls through the hoop". While it's *falling* and while we're talking about it passing through a hoop that is *10 feet away from the ground*, it is unambiguously a meteor. We can talk about the likelihood of it becoming meteorite in the (near) future if you want, but in the comic he's talking about a meteor and uses the correct terminology. 19:41, 7 July 2020 (UTC)

I'd just like to point out that this assumes cueball's odds of sinking a basket remain at 30% after hundreds/thousands of shots. One would think he would improve with practice. 23:53, 3 July 2020 (UTC)Duban

Randall expresses as much in the title text. --NotaBene (talk) 00:00, 4 July 2020 (UTC)
The psychological factor is another problem. The pressure of having reached a large number of shots will change how a person performs. Considering how sensitive the overall probability is to small variations in the success rate, this could have a dramatic effect, even if the overall free throw percentage doesn't change. 05:23, 4 July 2020 (UTC)

Cueball's odds of 30 consecutive baskets are 0.3^30 = 2.06*10^-16. Earth is hit by about 6100 meteors per year, and a basketball hoop has a radius of 9 inches. Using that it will be hit about once every 5.09*10^11 years. In order for it to be even, Cueball would have to do approximately one trial every 55 minutes. Since he'll start over each time he misses, it works out to once attempt every 38.6 minutes. DanielLC (talk) 00:36, 4 July 2020 (UTC)

(?Almost) no-one in recorded history has been killed by a meteor, so the estimate of 1 in 250,000 is based on a very small chance of a very large number of people dying from something like a "Dinosaur Killer" object, which would not fit through the hoop.

Ok. Area of hoop: 0.166 square meters. Area of earth: 510 million square kilometers, or about 3x10^15 hoops. The Planetary Science Institute thinks 500 meteorites per year; Cosmos magazine think 6100 per year (which will essentially all be small enough to go through the hoop). So we get 5x10^11 or 6x10^12 years for space to score. If Cueball had to do multiple sets of 30 throws and wait until one of those sets was all successes he'd take 5x10^15 attempts, so 1000 or 10,000 attempts per year for a fair game. Which seems ok.

On the other hand, suppose that any 30 consecutive success counts. In that case the waiting time is shorter, but not much shorter. [This](https://math.stackexchange.com/questions/893941/distribution-of-maximum-run-length-of-independent-multinomial-trials) suggests the average time for any 30 consecutive is the same as the average time for batches of 29 when you need to get all 29 in a batch. So the difference is smaller than uncertainties/approximations we're already ignoring

Since almost all meteors are incinerated and reduced to dust upon contact with the earth's atmosphere, it stands to reason that there may already be a (teeny-weeny bit of a) meteor already passing through the hoop. RAGBRAIvet (talk) 02:40, 4 July 2020 (UTC)

Technically it's still a meteor as it's being put through the hoop. The definition of a meteorite is a meteor that has *reached the surface* and made it through the atmosphere. The basketball hoop is not the surface. It is still a point in the atmosphere. Magma at any arbitrary point before it flows or erupts out of a vent (10 feet before the vent, for example, the same height as the rim of the basket on a regulation hoop) is still called magma and not lava. Therefore the entry should note this and refer to the meteors as such and not improperly as meteorites as the current note does. 07:32, 4 July 2020 (UTC)

This is what I was going to say, more or less. Though with the additional pondering of hoop-height to atmosphere depth (roughly) proportional to chance of a hoop-scorer attaining "-ite" status soon after. And then *something* *something* about the inherent status of a rim-shot (the chances being an interesting additional function of hoop diameter and the (surviving) cross-sectional width - and what if the latter exceeds the former?)... 10:01, 4 July 2020 (UTC)
There seems to be some debate about the terminology. I can find definitions that would make it a meteor (meteoroid in space, meteor in the atmosphere, meteorite on the ground) or a meteoroid (if a meteor is the light show rather than the rock itself). Angel (talk) 12:52, 4 July 2020 (UTC)

According to https://www.nasa.gov/astronauts/pettit_chron_10.html a 2001 study estimated the meteorite fall rate to one meteorite per million square kilometers per year, which yields an expected value of ~6e+12years to score for space. The Cosmos magazine article mentioned above may draw from the same source.

What about micrometeors? As I understand, they are a lot more common. Divad27182 (talk) 16:46, 4 July 2020 (UTC)

The explanation currently says "there are approximately 6 quadrillion seconds remaining in the expected lifetime of the Sun (5 billion years)". I don't understand where this comes from. My math says 5 billion years is around 158 quadrillion seconds. Pascal (talk) 00:52, 5 July 2020 (UTC)

Missed a spot, thanks. --NotaBene (talk) 15:18, 5 July 2020 (UTC)

The age of the universe isn't in the order of 8 billion years, should it be replaced with trillion or age of solar system?

13.8 billion years is close to 8 billion (factor of 1.7x), not one trillion (factor of 72x). --NotaBene (talk) 15:18, 5 July 2020 (UTC)

Harhar, *exercise* in futility.-- 21:07, 5 July 2020 (UTC)

I would like to take a moment to thank the multicellular Colonial organisms whose efforts lead us to the fireworks shows in the USA the day after this strip was published. These Are Not The Comments You Are Looking For (talk) 22:45, 5 July 2020 (UTC)

Oh, and don't forget that the meteor might bounce off the backboard, that'll increase the chances. Or does that turn it into a meteorite and thereby invalidate it? Jkshapiro (talk) 02:14, 10 January 2021 (UTC)

Note that both Randall and the commenters here seem to assume that the basketball hoop will remain in existence, and in place, for the remaining time until the red giant Sun engulfs the Earth (or possibly be replaced continuously by a never-failing civilization for billions of years). Nitpicking (talk) 12:30, 29 October 2023 (UTC)