Submitted 20 hours ago by gandalf_der_12te@discuss.tchncs.de to science_memes@mander.xyz
https://imgs.xkcd.com/comics/sea_level_2x.png
Alt text: They’re up there with coral islands, lightning, and caterpillars turning into butterflies.
What blows my mind even more, is, contrast to the fact that these tides are from Luna’s pull on Earth, which does not move the barycenter outside earth, the effect of Jupiter on Sol, does pull the barycenter outside Sol! Get your head around that, eh!?!!
I don’t recall what I was reading, but I once read about a lot of things lined up perfectly for evolution on Earth.
It’s bonkers that it all worked out that way so that I could be here, right now, reading your post and responding. It really boggles the mind and I don’t want to waste my time.
Welp, guess I’m gonna go look up random curse words in the dictionary. ಠᴗಠ
This is rather as if you imagine a puddle waking up one morning and thinking, ‘This is an interesting world I find myself in — an interesting hole I find myself in — fits me rather neatly, doesn’t it? In fact it fits me staggeringly well, must have been made to have me in it!’ -Douglas Adams
Lines up perfectly … for life as we know it. See also: The Anthropic Principle
But in the vastness of space, it was practically guaranteed to happen somewhere. There are a set of criteria that allow for the evolution of life (as we know it) and it was going to happen somewhere, the fact that it happened here is no more awesome than it happening 3 galaxies over.
I know the feeling you are describing and the words to describe what i am trying to say are hard for me to grasp.
Its like in a film where the hero survives seemingly impossible odds and people watching say “no way, thats impossible” and can’t enjoy the film because its too unbelievable. I say no! This is a story about the one almost impossible time all these things happened. Thats the point. Yes its hard to believe, but thats what makes it awesome.
So the earth being here and humanity and all other animals evolving here is just the time in the impossibly vast universe that the “stars aligned” and the fact that we are experiencing it is just expected.
But in the vastness of space, it was practically guaranteed to happen somewhere.
Do we know this for sure?
When we thoroughly shuffle a deck of 52 cards, we’re almost certainly creating a new deck order that has never been seen before and will likely never be seen again in a random shuffle.
The number 52! is 8 x 10^67, so large that we can make the equivalent of a billion (1 x 10^9 ) shuffles per second per person on earth (8 x 10^9 ), so that in any given millennium (3.15 x 10^10 seconds) we’ve covered a percentage so small it’s got 37 leading zeros after the decimal point for the percentage, or 39 leading zeroes for the ratio itself.
My impression is that factorial expansion for probabilities moves up much faster than the vastness of space itself, but I don’t know how to calculate the probabilities of each of these priors.
How does having a moon and the tilted axis contribute to evolution?
IIRC; Tilted axis gives us the seasons by doing so causing weather and water streams. Also lightning. Having a moon causing the tides is what’s believed to be the reason for the chemicals in the dirt and rocks mixing well to prepare the amino acids or something similar.
There are a few reasons but I kind of think it boils down to biodiversity. Seasonal changes, tides, light exposure, and varying temperatures would affect the balance of diverse life.
For example, Earth didn’t always have oxygen. 2.4 billion years ago there was a bunch of microbial photosynthesis happening. Seasons and the tides affect ocean currents which moved nutrients around, allowing the bacteria to thrive and grow.
Ozone’s formula is O~3~, so the Ozone layer wouldn’t have formed either.
There are also other issues like how the seasons affect biological migration or how the moon slows the Earth’s rotation to about 24 hours/day.
Seasons add variability, which helps select life that is adaptable and less likely to be wiped out.
Moon keeps the ocean moving, circulating the oxygen and nutrients.
‘lined up perfectly’ is a stretch, considering it’s safe to assume these ‘perfect’ conditions have appeared more than quadrillions of times within the universe
…and of course we’re in the darkest parts of that universe, so we will never be able to experience other similar worlds. Damn.
Oh for sure. The universe is too big for it to not have happened elsewhere. I’m not saying it’s unique, just rare.
For me, it was the fact that the Earth is tilted at just the right angle that sort of blew my mind. Too much one way or another, we wouldn’t have seasons or day/night cycles.
From under, other planets have been identified with the potential for life, but don’t have the tilt or the moon.
The sole fact that we’re here means that we don’t even have to think about those, but yeah.
Our planet is scifi as hell. We’ve got natural magnetic shielding to protect our UV-blocking ozone layer from solar winds. This planet is so damn cozy<3
This planet is so damn cozy<3
Oh! Oh! Let’s wreck it by polluting the hell out of it :3
For now
I think it’s more wild that not only are big moons rare, ours is literally the same size as the sun from our point of view.
It also makes almost exactly 13 laps for every lap the sun makes.
Which is why a 13 month calendar all having 28 days would have made more sense
It makes 12 months because the lap the Earth makes is deducted from the 13 the moon makes, so effectively it makes 12 cycles around the Earth.
12 is an easier number to work with because of how many factors it has
Landlords would love it, at least. I personally would hate it, being a renter.
13 is a unlucky superstition number.
Didn’t some cultures do that?
And from what I have heard on science podcasts, the moon is, and has been, and still will be, moving away from the earth. Making the perfect solar eclipse only for a segment of the earth’s history.
It honestly makes me feel lucky being born when I was.
We also get to see the after effects of the big bang which won’t be detectable for the majority of the lifetime of our universe.
It’s almost like someone put it there on purpose 😉
Gross
Winter is kinda wild too. The fact that the planet is tilted just enough to make it cold part of the year, but not so cold that it kills everything, and many plants and animals have integrated this into their life cycles.
Evolutionary niche fits the conditions.
If only we could cap our carbon emissions enough to keep it that way. But at least the top one percent are making money
I get similar feelings about earth when I can see the moon during the daytime. Something about seeing it with clear craters against the blue sky makes it feel much more like we’re just floating in space with a cratered barren partner.
And the sci-fi cliche is to have enormous moons filling the sky, but realistically, ours is comically large. Even planets in our solar system mostly see moons the way we see those planets. You get a dot.
Only Pluto and Charon got us beat.
At least in terms of lower mass difference between the two bodies, and the distance the barycenter is moved from the center of the larger body.
[Edit: … maybe Eris and Dysnomia come close too. … and worth another mention that Jupiter tugs the barycenter further from Sol than Luna does from Earth. But all that’s a different beast from visual size.]
Damn, now I get why cartographers and the like always try to make it prettier in post!
Never thought I’d be body shaming the Earth, but here we are 🤷
If the Earth was scaled down to the size of a billiard ball, it would be the smoothest billiard ball in existence.
That is pretty severely exaggerated though to emphasize the form.
Lol, but the diff is actually x10000 or something, to make it more visible
Its the water that makes the world go around
I like to read science history books, the process of discovery and methods people come up with in search of answers is fun. Anyway, I read a whole book about tides, and one of the reasons people thought the tides rolled in and out was because somewhere in the ocean, a massive creature was slowly breathing in and out enormous volumes of water. These same people still went out on boats.
I’m sorry 1k upvotes? Did I accidently open Reddit without noticing?!
I wonder if life would exist on our planet if there were not tides.
The Sun also creates tides, just not as strong as lunar tides. So we would still have tides, even if we had no Moon.
The Sun also creates tides
The second worst British tabloid? I highly doubt it.
And seahorses! Dont forget them!
Hearts in their head. Males carry the babies.
They’re insane!
Can’t forget magnets. How do they work?
Magitech.
Only if Knowledge doesn’t get her way. But considering Travis…
Like other elements, just a bit farther reach with their fields. Fun fact, nothing is solid. When you try and touch something, it's actually just forces against forces. Atoms are primarily made of nothing.
I feel the (strong) force.
Exoplanets could have tides too though…
It’s unlikely that there are many exo planets with a moon as big as the Moon. Much more likely to have small ones like Mars. Mercury, Venus and Mars are all great examples of bad shit that can happen to planets: Tidally locked + too close to the sun, rolled over on the side, and finally Mars too small to maintain a molten core and magnetic field. The Moon helps avoid the Venus situation and maybe the Mars problem.
Our moon has a name, it’s Luna
Do you think “big enough moon” is going to be similarly rare to “liquid water”? We’re getting better and better at finding planets. Not sure how we’d find their moons though.
Well it’s not near the surface but rather far away in comparison. But also really big a moon.
I’ve always thought this about Opal stone. It looks like a made up stone from an alien planet.
At some point I saw a yt science video saying the water isn’t moving the dirt bit is moving
and i don’t understand why the tides on the RIght Hand coast are like clockwork and the Left Hand side of the country the tides are like “what time is it IDGF HIGHTIDE”
Some of the first mechanical calculators were created to predict tides (~3 centuries ago), because they are a really complex thing that the popular explanations completely paper over and pretend it’s simply the water keeping pace with the Moon.
It’s shown like that because the water is trying to do that, to anthropomorphise it. Though of course that’s not what the water does everywhere because fluid dynamics get pretty nuts when there’s a ton of land in the way.
I’m not sure what that video said, exactly, but both water and dirt move because they are both affected by tidal forces.
Tide is caused when an object, like Earth, is large enough to experience a difference in the effects of orbital gravity from one end to the other. The center of gravity of an object does not experience tidal forces.
Since most of the Earth’s surface is water, and the water is on top of the dirt, the water should be affected more by tidal forces than the dirt underneath it.
The video may have been talking about how the dirt affected by tidal forces also pushes the water, causing a compounding effect or something.
In the video he’s saying the line between center of moon and center of earth has the most tidal force on the water, while the earht spins through that zone. It was not saying that the water starts 100% stationary and land spins through it, just that the height of water will always be high at that line as the earth rotates
The tides are also likely responsible for advanced life on this planet. So there is that.
I always wondered how quickly the tides actually change. If the moon is directly overhead, does the tides at the lowest or the highest? Or does it just pushes things around and it’s just different?
Think about the moon like a flashlight beam. Where the center hits the ocean, it keeps a consistent pull upwards, and moves the bulge of water as it orbits. Towards the edges of focus, it’s dropping a bit of water and it’s rippling away as it falls. I am no scientist, but I liked this explanation when I saw it because it was simpler to understand.
It’s because the center of mass between the earth and moon is off center, nearly 3k miles from the core, and constantly moving as the moon orbits.
So it’s not due to a direct pull, and the earth’s orbit around the sun technically has a slight wobble due to it.
Also the moon being at the right size and distance that it looks to be the same size as the sun from earth, and our eclipses can be total.
It’s your turn Cueball.
What’s up with the alt text?
It’s xkcd’s alt text or sub-captions; not accessibility alt text.
mnemonicmonkeys@sh.itjust.works 1 hour ago
By far the coolest and most unique aspect of the Earth-Lunar system is solar eclipses. The size and orbital distance is just right to allow for the spectacle we get today.
This is even more true when you consider that the Moon’s average orbital radius is increasing by 3" (76mm) each year. In a million years, the Moon will be too far away to fully cover the Sun. A few million years ago it was close enough to fully cover the corona