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One of the more remarkable facts about life on Earth is that the Moon and the Sun are the same size in the sky. This is astronomically unlikely. Our moon had to

One of the more remarkable facts about life on Earth is that the Moon and the Sun are the same size in the sky. This is astronomically unlikely. Our moon had to be enormous for this to work out. I also find it rather strangely fortuitous that our year is about 360 days, which makes the math for the calculating how much the night sky changes every night particularly easy. There is no reason for this to be the case. Just a riff: gravity is really the force that gives rise to life, since it's the force that compresses matter into light-emitting masses we call stars. It's also in those infernos that the heavier elements were formed in previous generations of stars, such that they could accrete into a planet, and then (eventually) get arranged into a physical system, and power that system, such that it could express it's own arising with a pattern of controlled motion it might call "typing".

IvyMike 11y ago
The fact that the chances for a planet with a solar eclipse like ours is so tiny makes for a plot point in several science fiction books. One example, from Iain M. Banks' Transition: > But what I want to propose to you is that, as well as all those other wonders, they would definitely want to see that one precious thing that we have and probably nobody else does. They’d want to see our eclipse. They’d want to look through the Earth’s atmosphere with their own eyes and see the moon fit over the sun, watch the light fade down to almost nothing, listen to the animals nearby fall silent and feel with their own skins the sudden chill in the air that comes with totality. Even if they can’t survive in our atmosphere, even if they need a spacesuit to keep them alive, they’d still want to get as close as they possibly could to seeing it in the raw, in as close to natural conditions as it’s possible to arrange. They’d want to be here, amongst us, when the shadow passes.
simonh 11y ago
Ulikelieness is hard to reason about though. Suppose we were to list all the different metrics that describe our world and solar system. How long would the list be? Then think of all the possible synchronicities there might be between all those attributes. There might be many millions or billions of possible 'magic' ratios and equivalences. So if the chance of any particular synchronicity randomly occuring is one in a million, you'd expect to see many synchronicities in the data set, just by random chance. It's one reason I'm skeptical of probabilistic evidence in court cases. Suppose the chance that soem particular piece of evidence linking a suspect to a crime has a 'one in a million chance' that it would be randomly associated with someone other than the perpetrator. Sounds convincing, looks like this person probably did it. Well, there are 60 million people in the UK. Does that mean we would expect about 60 of them to be incorrectly incriminated by this evidence? Suddenly it doesn't sound so convincing. It's also a problem in 'big data' analysis. If you have many thousands of items of data about people, if you try to find correlations in that data with some characetristic of interest, such as tendency to some medical condition or insurance risk, as the number of factors expands the chance that you'll find completely spurious correlations also goes up until it becomes near-certain.
deciplex 11y ago
> I also find it rather strangely fortuitous that our year is about 360 days, which makes the math for the calculating how much the night sky changes every night particularly easy. Can you elaborate? I guess you're referring to the fact that the number 360 happens to be highly divisible, but I'm not sure.
- lovemenot 11y ago
  I think javajosh's first two points were intentionally designed to be picked apart. Yes, 360 is a highly divisible number, but then current years are not actually 360 days. And anyway both apparent moon size and year length in days are not fixed, but variable. javajosh's point, I think, is that one can always make something appear to fit magically when your perspective is arbitrary.
  - javajosh 11y ago
    Actually I was being serious. So, 360 degrees is useful for dividing a circle into pieces, because it's divisible in lots of ways (particularly fourths, thirds, and so on). It's small enough to be manageable but large enough to let builders, for example, speak in terms of "one degree". I bet that any intelligent, tool-using life would pick 360 for dividing circles. If you're doing astronomy, you'll notice that every night the stars "advance". That is, if you do your seeing at midnight every night, the stars will look slightly different each night. In fact, they'll look (roughly) 4 minutes older, corresponding to one degree of rotation. If you do this for a whole year you'll see the same sky at midnight again, a year later. (Another way to think of this is that there's a line passing through the sun and earth that, at midnight at any point on earth, points in a different direction every evening of the year. There are 365 of these lines, and they are (almost) exactly one degree apart.) I think that's really a pretty coincidence. (Now, it's true that it would also be remarkable if our year was 100 or 1000 days. That would be remarkable for a different reason of course.)
    - Retra 11y ago
      There aren't actually 365 days in a year, it's only approximate, and we force upon ourselves a ton of (highly inconvenient) work to make that approximation work day-to-day. >(Now, it's true that it would also be remarkable if our year was 100 or 1000 days. That would be remarkable for a different reason of course.) I think that's lovemenot's point: If you accept arbitrary reasons, everything will be remarkable. See: https://en.wikipedia.org/wiki/Interesting_number_paradox https://en.wikipedia.org/wiki/Interesting_number_paradox

IvyMike 11y ago

The fact that the chances for a planet with a solar eclipse like ours is so tiny makes for a plot point in several science fiction books. One example, from Iain M. Banks' Transition: > But what I want to propose to you is that, as well as all those other wonders, they would definitely want to see that one precious thing that we have and probably nobody else does. They’d want to see our eclipse. They’d want to look through the Earth’s atmosphere with their own eyes and see the moon fit over the sun, watch the light fade down to almost nothing, listen to the animals nearby fall silent and feel with their own skins the sudden chill in the air that comes with totality. Even if they can’t survive in our atmosphere, even if they need a spacesuit to keep them alive, they’d still want to get as close as they possibly could to seeing it in the raw, in as close to natural conditions as it’s possible to arrange. They’d want to be here, amongst us, when the shadow passes.

simonh 11y ago

Ulikelieness is hard to reason about though. Suppose we were to list all the different metrics that describe our world and solar system. How long would the list be? Then think of all the possible synchronicities there might be between all those attributes. There might be many millions or billions of possible 'magic' ratios and equivalences. So if the chance of any particular synchronicity randomly occuring is one in a million, you'd expect to see many synchronicities in the data set, just by random chance. It's one reason I'm skeptical of probabilistic evidence in court cases. Suppose the chance that soem particular piece of evidence linking a suspect to a crime has a 'one in a million chance' that it would be randomly associated with someone other than the perpetrator. Sounds convincing, looks like this person probably did it. Well, there are 60 million people in the UK. Does that mean we would expect about 60 of them to be incorrectly incriminated by this evidence? Suddenly it doesn't sound so convincing. It's also a problem in 'big data' analysis. If you have many thousands of items of data about people, if you try to find correlations in that data with some characetristic of interest, such as tendency to some medical condition or insurance risk, as the number of factors expands the chance that you'll find completely spurious correlations also goes up until it becomes near-certain.

deciplex 11y ago

> I also find it rather strangely fortuitous that our year is about 360 days, which makes the math for the calculating how much the night sky changes every night particularly easy. Can you elaborate? I guess you're referring to the fact that the number 360 happens to be highly divisible, but I'm not sure.

lovemenot 11y ago
I think javajosh's first two points were intentionally designed to be picked apart. Yes, 360 is a highly divisible number, but then current years are not actually 360 days. And anyway both apparent moon size and year length in days are not fixed, but variable. javajosh's point, I think, is that one can always make something appear to fit magically when your perspective is arbitrary.
- javajosh 11y ago
  Actually I was being serious. So, 360 degrees is useful for dividing a circle into pieces, because it's divisible in lots of ways (particularly fourths, thirds, and so on). It's small enough to be manageable but large enough to let builders, for example, speak in terms of "one degree". I bet that any intelligent, tool-using life would pick 360 for dividing circles. If you're doing astronomy, you'll notice that every night the stars "advance". That is, if you do your seeing at midnight every night, the stars will look slightly different each night. In fact, they'll look (roughly) 4 minutes older, corresponding to one degree of rotation. If you do this for a whole year you'll see the same sky at midnight again, a year later. (Another way to think of this is that there's a line passing through the sun and earth that, at midnight at any point on earth, points in a different direction every evening of the year. There are 365 of these lines, and they are (almost) exactly one degree apart.) I think that's really a pretty coincidence. (Now, it's true that it would also be remarkable if our year was 100 or 1000 days. That would be remarkable for a different reason of course.)
  - Retra 11y ago
    There aren't actually 365 days in a year, it's only approximate, and we force upon ourselves a ton of (highly inconvenient) work to make that approximation work day-to-day. >(Now, it's true that it would also be remarkable if our year was 100 or 1000 days. That would be remarkable for a different reason of course.) I think that's lovemenot's point: If you accept arbitrary reasons, everything will be remarkable. See: https://en.wikipedia.org/wiki/Interesting_number_paradox https://en.wikipedia.org/wiki/Interesting_number_paradox