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.


Ambox notice.png This explanation may be incomplete or incorrect: Created by a METEORIC BASKETBALL. Should discuss expected time to make 30 shots in a row at 30% (and other percentages), and odds of meteorite impact, and NBA Jam and Space Jam. Do NOT delete this tag too soon.
If you can address this issue, please edit the page! Thanks.

This comic strip is another one of Randall's strange hobbies (released within the same week as his last hobby comic, 2326: Five Word Jargon). Because of the ongoing COVID-19 pandemic, or perhaps just due to his difficulties in making friends (cf. 1917: How to Make Friends), Randall wishes to play basketball but has nobody to play with, and so he chooses to play against outer space. His goal is to make thirty baskets in a row before the universe puts a meteor through his hoop.

Randall estimates that his success rate at free-throw shooting is approximately 30%. 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%.

However, the chances of Cueball getting 30 hoops is (0.7)^30, or about 0.002253934029 percent. (compare this to the chance of meteor


Ambox notice.png This transcript is incomplete. Please help editing it! Thanks.

[Cueball is standing in front of a basketball hoop, holding a basketball.]

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)