"What was most significant about the lunar voyage was not that men set foot on the Moon, but that they set eye on the Earth." -Norman Cousins
What would life on Earth be like without the Moon?
Our nearest neighboring body in the cosmos has a profound effect on us. It's helped not only shape our evolution, biologically, but has shaped the entire evolution of our planet. Created some 4.5 billion years ago -- when our planet and Solar System were still in their infancy -- when a roughly Mars-sized planetoid crashed into a young proto-Earth, the Moon has been our companion-in-orbit ever since.
It's totally reasonable and conceivable that life would have sprouted and thrived on Earth even without the Moon, but things would be significantly different in detail. Some of them would be obvious, some would be a little more subtle, but there would be a great many impacts that we'd notice if we knew to look for them.
So today, I present to you the top 5 things we'd miss if we didn't have a Moon! (And no, "landing on the Moon" didn't make the list!)
1.) There'd be no such thing as eclipses on Earth.
Without the Sun, Moon and Earth, there would be no eclipses. The Sun is constantly shining on Earth, casting a shadow for over a million miles (and over a million kilometers) in its wake. Yet without our Moon -- just a few hundred thousand miles (or kilometers) away -- there'd be no object that would pass through the Earth's shadow; there'd be no lunar eclipses.
There'd also be no solar eclipses: no annular, partial, or total eclipses. The Moon's shadow is almost exactly equal in length to the Earth-Moon distance; without the Moon, no shadow, and no disc to block the Sun's disk. The next largest object that can pass in between the Earth (after the Moon) is Venus, and while it's incredibly cool when that happens, that's the closest we'd get to an eclipse without the Moon.
2.) Our tides would be tiny in comparison to what they are now, and they'd be dominated by the Sun.
Although the Sun is some 400 times larger (in diameter) than the Moon, it's also, on average, about 400 times farther away. This explains why they appear about the same angular size from Earth. But the Sun is only about 27 million times as massive as the Moon.
Why in the world would I say "only" there? Because it would have to be about (400)3 times the mass of the Moon, or 64 million times its mass, in order to have the same effect on Earth's tides as our small, lunar neighbor. As it stands, tides from the Sun are only about 40% as strong as tides from the Moon. When the Sun and Moon line up in either the "new" or "full" Moon phases, we get spring tides, 140% as large as a typical tide, and when they're at right angles, we get neap tides, only 60% as strong as a standard tide.
But without any Moon at all, our tide patterns would be much simpler, and only the Sun would contribute anything substantial. So our tides would only be about 40% as large as a typical tide is today. Not the biggest of deals, but definitely something we'd notice.
But there'd be some very large impacts on how we experienced life on Earth.
3.) Nights would be much, much darker than we're used to.
If you've ever been outside in the wilderness on a totally moonless night, without any artificial light, you probably noticed two things. First, the night sky is absolutely breathtaking; you can see thousands upon thousands of stars, the plane of the Milky Way, and even dozens of extended, deep-sky objects with your naked eye alone. And second, you can't see a damned thing in front of your own face.
The Sun is much, much brighter than the Moon; the full Moon is just 1/400,000th as bright as the daylight Sun. Yet Venus, the next brightest object in the night sky, is only 1/14,000th as bright as the full Moon!
We have pretty decent night vision, so long as the Moon is out. But without it, our night vision is, well, not very effective, as anyone who's been camping without a headlamp or working flashlight can testify. It's probably safe to say that vision would have evolved somewhat differently without the Moon, and that our nights would provide us with a wildly different world to experience.
But that wouldn't be the biggest difference, not by a long shot.
4.) A day on Earth would be much, much shorter; only about 6-to-8 hours, meaning there'd be between about 1,100-1,400 days in a year!
Our 24-hour-days may seem like they don't change from one year to the next. In reality, the change is so tiny that it took centuries to perceive, but the Earth's rotation slows down ever so slightly over time, thanks to the tidal friction provided by the Moon. The slow-down is very, very slow (on the order of microseconds-per-year), but over millions and even billions of years, it adds up!
In about 4 million years, we'll no longer need leap years to keep our calendars on track. If the Sun would live an infinite amount of time, the Earth would eventually slow down and become tidally locked to the Moon, the same way the Moon is locked to us and always shows us the same face. Instead of 24 hours, a day would last for some 47 current Earth days. (In reality, the Sun will end its life long before that happens, so no worries there.)
But in the meanwhile, we can use what we know to extrapolate backwards in time, and we find that in order to get a 24 hour day today, the Earth had to have been spinning much faster in the past: about three-to-four times as fast more than four billion years ago! If we didn't have a Moon -- if we never had our Moon -- the day would be much, much shorter than it is today, and our planet would have a larger equatorial bulge, much more flattened poles, and over 1,000 days in a year!
5.) Our axial tilt would vary tremendously over time!
You probably learned that the Earth rotates on its axis, tilted at about 23.5 degrees relative to its orbital plane around the Sun. This is true! But did you ever stop to think what keeps the Earth from changing the tilt of its axis-of-rotation? The same way a spinning top not only precesses but also exhibits more complicated motion over time (some of which you may know as nutation), an entire planet can do this, too. Mars is a perfect example: currently tilted at about 24 degrees relative to the Sun, we know that its axial tilt varies from about 15 degrees to about 35 degrees over time!
Earth is special, though, because we have an external force to stabilize us against that sort of behavior. Know what's responsible?
That's right, the Moon! Thanks to our Moon, our axis stays tilted between 23 and 26 degrees over time, even over hundreds of millions of years! But without our Moon, there would be nothing preventing catastrophic shifts in our rotational axis. It's probable that sometimes, we'd be like the planet Mercury, orbiting in the same plane as our rotation, and having practically no seasons due to our axial tilt. At other times, we'd possibly be as extreme as Uranus, rotating on our side like a barrel, having the most extreme seasons imaginable!
So the next time you take our Moon for granted, think about how different life would be -- and how different the entire history of life on Earth would have been -- if we didn't have our Moon!
If our tides had been much smaller. Life in our oceans would have had to have been much smaller. General mathematics.
Life began in the ocean. Elements,Minerals electrical exchange motion=life! Actually complete mathematical perfection. Until our wonderful egos stepped in. Pollution, war.
Ethan, sorry for asking the same question again... But you wrote some time ago, that our Moon can't lock the Earth, because the Sun is much more powerful...
Excellent article, as always, thanks!
@Jnecolong -- Citations, please, for your unsupported pseudo-poetic assertions?
Tidal motion is extremely variable, and dependent primarily on the details of coastal shape (compare the Bay of Fundy to Cape Cod, for example).
The "size of life" is a content-free phrase. Are you discussing the sizes of bacteria, protists, Vendian forms, modern plants, or multicellular animals? The latter range over roughly six orders of magnitude size. How exactly does that correlate to tidal motion?
This is just speculative since I'm just a layman, but how about this for your list?
6.) No Plate Tectonics
If the moon-creating collision had never occurred the Earth's outer crust would have been thicker & we wouldn't have had plate tectonics. This would have led to increased, massive volcanism to shed heat like on Venus or the massive stacked volcanoes of Mars. Erosion would flatten all high spots with only volcanoes to rebuild mountains & thus we would end up with mainly a water world
7.) Different Atmosphere
I'm unsure about this... Suppose there was carbon-based life on Earth despite the lack of plate tectonics in 6.) above. The carbon cycle would have a much smaller throughput which would lead to a greenhouse effect like Venus.
7.) Smaller Magnetic Field Sooner
I read somewhere that plate tectonics effects the molten outer crust. No plate tectonics would lead to a reduced or zero magnetic field much sooner in Earth's history. The mechanism wasn't explained in the article so I have some doubts about this.
Michael Fisher -
There is speculation that without the Moon-forming event, we would have a much smaller Iron core and hence no magnetic field - we'd be more like Venus.
Why Venus has a different tectonic style to Earth is something of a mystery (or was when I last looked).
"But in the meanwhile, we can use what we know to extrapolate backwards in time, and we find that in order to get a 24 hour day today, the Earth had to have been spinning much faster in the past: about three-to-four times as fast more than four billion years ago"
The validity of such extrapolation to 4 billion years ago is questionable, though.
"The Earth four billion years ago may have had an eight-hour day" would be more apt.
Another effect is the shield that the moon provides us with. How many large rocks would have hit the Earth that instead hit the moon. Extinction events would be more common.
I noticed how bright a full moon was, and how dark it is without a moon while on my uncle's farm during the summer.
I suspect that the fable of crazies, thieves, etc. coming out on a full moon originated before there was electric lighting. Nowadays, with city lighting at night, and flashlights and headlights available at night, the moon should have no effect, but pre electricity someone up to no good could operate most effectively when the moon was close to full.
About the Earth axial tilt variation with or without the Moon.
It's counter-intuitive. I would readily believe the opposite, that in general the presence of a large moon would make things _less_ stable.
Let me recapitulate the difficulties, as I understand them.
The effects are very subtle. In a sense the dynamics is not understood.
Researchers design computer-models, those models are run multiple times, with slightly different starting conditions.
If the system remains stable in all of the runs then that's a good indication the system is inherently stable. If there are significant excursions in some or all of the runs then apparently the system is not stable.
So the point is that the information that is obtained from the runs is statistical only. There is good reason to trust the outcomes, but the research does not offer a window on _why_ the presence of the Moon makes a difference.
I came across an article published in 2011. The authors report that while they found a with-moon and no-moon difference, the difference was small.
They did see some large tilts in some of the runs, but the tilt always changed so slowly that it would not interfere with life on the planet.
The earth, like any spinning object, is not entirely a sphere but an oblate spheroid. That means that if the tilt of the axis of rotation moves, then the equatorial bulge will move and this will affect the gravitational field felt by another object in space, the closer the more it is felt.
E.g. the moon.
That would cause a force on the moon which doesn't WANT to be moved and the reaction will dampen out the movement of the earth.
Stephen Baxter wrote up an interesting bit on the Earth minus a moon. A few things he said might happen:
-- less tidal mixing, so there would be very different biota. The gas and chemical exchange would be dominated by runoff.
-- faster winds (since the planet would rotate faster). Stronger storms, an atmosphere much more like a Jupiter in its dynamics. (Obviously it wouldn't be exactly like, but the wind pattern would be similar).
-- A higher CO2 level in the atmosphere, more like Mars or Venus. Note that most terrestrial planets have CO2 as the dominant atmospheric gas. Even Europa has that, though it's mighty thin. Titan is the only major exception I can think of.
Great post. One thing left out though: the Moon has been slowly moving away from us. Around the time that life first formed, the Moon was in a very close orbit, and the tides were HUGE. Some estimates of over a thousand feet(!)).
It is speculated that the mixing of solids into the early ocean from the enormous tides played a significant role in early oceanic geochemistry that produced life.
Imagine standing on mountain by the sea, and watching a thousand foot tide come in!
What would the period of the nutation be? Can we estimate an order of magnitude?
Wouldn't there be no life
I'm not sure why there'd be no life without the moon. I'm guessing you are thinking of the role of tidal pools in abiogenesis, but I'm not sure that there's solid evidence that this is where life actually formed. If life formed in the oceans (such as in thermal vents, for instance) lack of a moon would have no effect.
I am sure, though, that lacking a moon, the intertidal habitat would have been affected. This would likely have led to differences in how species evolved, and we likely would see different types of species than we actually do.
Life would have a lot of problems lasting stably for long enough to evolve as far as what the-man-in-the-street would call life.
You may be thinking "bacteria and self-assembling virii" as "life" and others thinking "something you can point to and go 'that's a living organism'".
Another good read on this topic is Isaac Asimov's "The Tragedy of the Moon".
Fair enough, Wow, but while I'm no expert on biology, I have taken a couple of courses. In all of them, we did deal with kingdom prokaryota. If the poster meant multicellular life, he should have stated that.
It isn't about how much biology you know, but what you'd consider life to be life when you are looking for somewhere to lay your hat.
A planet occupied by bacteria and amoeba may be a worry for infectious disease vectors, but we wouldn't say "we have to move on because this planet is inhabited", would we.
But if something were there that appeared to us to be a macro-scale animal comensurate with, say, a dog or dolphin, we may well decide that it is already occupied.
The difference not being how many cells it has, but as to whether we can morally take the planet over.
"It has single celled life" is *scientifically* a huge thing to know.
"it has single celled life" is for the future of mankind, damn pointless.
I'm curious about this 8 hour day without the Moon. You get this figure by projecting backwards from the current rotation rate and the steadily changing Earth-Moon distance. My problem with this method is that the Earth-Moon system was created in a collision event, which must have imparted some change in rotation to the proto-Earth. So, in truth, do we not know the initial condition of the system? Of course, I've seen some excellent models of the collision. Maybe those experts have not only projected back the current motion, but also have done the math for the collision.
Ha, maybe *I* should do some more reading and satisfy my own curiosity.
"In about 4 million years" - would "billions" be more correct?
I don't think I understand the comment about the Earth's axis of rotation precessing about -- shouldn't the angular momentum of the Earth be conserved?
It is. Precession is another rotation.
Throw a ruler up in the air and watch the longitudinal spin change to axial spin.
Just two comments from me, a member of our planet. 1. The Moon - Please keep off. If everything science says is true then we should leave our moon alone for us to survive.
2. There is a very good chance that other planets with moons have some life forms also.
you guys didn't help at all.
im kidding you guys did help
If the moon was not there the night's would be colder than usual because the moon keeps the night's temperature proper.
There would also be no ocean tides.
The sky during the day would be less bright because ther is no moon.
The days would actually be only 12 hours due to the axis spinning faster
What would happen if there were no lunar phases?
hi nice article
Hi! That's great informations to me & my students(Grade 8).
Hi! That's the greatest informations for me & my students(Grade 8 students).
The big bang theory is so wrong, for one main reason and many others
#1 main reason) the theory says the earth was made from a particle smaller than an atom but in Genesis (Holy bible, First Chapter, New Testament) it says, and God created the earth and the galaxy and everything on it, from nothing.
Evolution is wrong to, because in Genesis, God did not breathe life into the animals, in other words, he didn't give them a spirit, so, so, sorry you animal huggers, pets do not go to heaven, But god did breathe life into us, humans. so if animals evolved in to humans, He would have breathed life into animals, but, as i said, he didnt. Listen to me people, i am 11, but i got moved to the 9 grade, because of my biblical, and mathematical, reading, English, scientific, geology and history knowledge, i am supposed to be in the fourth grade!!!!!!! please listen to me, and if you want to comment my comment, please text me @ 8653470617, and i will try to get to you as soon as possible!!!
the theory says the earth was made from a particle smaller than an atom but in Genesis
One, that's not the theory.
Two, the "theory" in Genesis is a load of bollocks. For a start there are two mutually incompatible versions of it. Secondly, none of it has any evidence other than someone's say-so. If taking someone's say-so is sufficient, then you have no reason to discard the big bang theory because someone says it's true, which is acceptable proof for you.
Oh, and another thing. Fuck off. This isn't the thread for talking about the big bang and this isn't the site for discussing stone age myths held by the credulous and ignorant.
We spend shitloads of money keeping places for you people, GO USE THEM. They're called churches.
You use your space, leave the internet to those who have a brain and wish to use it.
The moon has slowed the earth's rotation. As it slows gravity wants to pull the earth back to a sphere, which it is not now because the rotation makes the planet wider at the equator than at the poles. The is the origin of tectonic plates, of the rise of the dry land. With no moon, there would be no earthquakes, probably no volcanoes, no dry land. Also there would be no magnetosphere and so any atmosphere would have been blown away by the solar wind.
For sometime there has been debate on how the moon effects the sediment in the wine vessels.
1)Does the moon effect the sediment?
2)Does the location on earth determine which moon to use when siphoning wine as to leave the sediment behind?
that info is great i think i could take same of those facts and put the on my own speach.
my class mates love that info and we have been tryiing to work out the moon.
Nice article and its very interesting
this is awesome
You missed one important thing: the highly unstable climates. Because the moon keeps us stable, without a moon the earth would start to have a wobbly orbit around the sun, and therefore our climate would not be stable as they are now.
without the moon to oxygenate the oceans, through weather and waves, we would have no fish and no land animals to have evolved from them.
Random questions we ask lol?
"1)Does the moon effect the sediment?"
Somewhat more than the presence of a nearby delivery truck, but less than that of the rumble of the highway traffic running past.
"2)Does the location on earth determine which moon to use when siphoning wine as to leave the sediment behind?"
No. We have only the one. And the effect the one we have is less than the disturbance of moving the wine from the container when siphoning it off.
WHERE are these "discussions" taking place?
Because I would like to avoid getting any product from people so clueless and worrisome.
I love the moon
The thing I'd miss most about the Moon is it's sheer beauty.
You guys are all idios im the smartest guy in the worl here and listen up! I know that im actually an alien! ALIENS ARE REAL! ALIESN AHVE 10 eyes and can rekt the human race if I wnated them to so yeah idiots bxtches
P.S Good Article ;)
Oh piss off.
ya it was so nice.......
I only came here after seeing the Der Eisendrache easter egg ending from Black Ops 3 Zombies.
Facinating! Over my head but it was very informative and interesting. Thanks!
One question, please. Why didn't that planet that hit a developing earth just either become a part of it or shatter it? How did it come to be orbiting it instead? Thanks!
Very interesting read and some more insight into our planet as 7yr old brother learning about our solar system
Sam Plats has the closest of this thread. Maybe when the proto planet (moon) crashed into this planetoid, it had more iron than other spheres. It exchanged most of its heavy materials and it reformed into a orbit around its victim collecting materials from its collision. The remaining iron retained by a prepubescent moon, hot in its state of reformation, kept the bulk of its iron on the near side of what we now call earth. It also explains the moons locked orbit, and as it gained mass explains its perpetual orbital increase. Without the moon in orbit, this planet would have no tilt, no tectonic shifting, and weather similar to a planet round as Mars. The iron it brought with it created a magnetic shield that protects us all, and possibly the best hope for life in this universe. And it is beautiful when its full!.
The question is that the four seasons are not formed through a full cycle of the Earth around the sun, but in another way as if a moving sine function, and the sun runs in its path to reach the end point, dead end
That is scary
this article is the biggest load of hotdog, I have ever read.
First numb nuts. Pay attention.
If the moon was not connected to the Earth, There would be no life on Earth.
Why .... well for the fools who do not believe in God.
The moon is required to regulate the Earth magnetic fields, provide weather patterns influence that work in conjunction with the Earth's atmospheric shield.
Did you know it is the moon that causes plants to grow taller and not the sun?
Now let me really confuse the .... out of you.
If the moon was not so important to a planet why does every other planet have a moon?
Why does this planet here alone present as if it was designed to support organic life-forms? eg scientist.
Oh and lastly god did not create the universe, planets or even the man named Adam whom he bought to life. God made all of this not created. But God did create something Now what was that?
if the moon was no longer there the oceans would become much calmer.
the sun will still have an effect on them (known as solar tides),so surfers would not be completly devoid of them.
i am a year sevin and i am useing (what if the moon was no longer there) as my speech topic.????
"If the moon was not connected to the Earth, There would be no life on Earth."
Yes there would.
"Why …. well for the fools who do not believe in God."
You mean those who need a reason to think something is real? I don't think they're called "fools".
"The moon is required to regulate the Earth magnetic fields"
The moon doesn't do that.
", provide weather patterns influence that work in conjunction with the Earth’s atmospheric shield."
The moon doesn't do that either.
And neither are NECESSARY for life to exist, even if the moon did do that.
"Did you know it is the moon that causes plants to grow taller and not the sun?"
No, we didn't know stuff someone made up out of thin air.
"If the moon was not so important to a planet why does every other planet have a moon?"
Why would every other planet having a moon (they don't, by the way) make having a moon either important or required for life to arise???
"Why does this planet here alone present as if it was designed to support organic life-forms? eg scientist."
Well,given it doesn't appear to be designed for that, why is your why even existent?
"God made all of this not created. "
"But God did create something Now what was that?"
Nothing. Nothing was created because god didn't exist to create it.
This is all speculation, yet you take it for science. There is absolutely no way to prove your theories. You say that the moon was created by some cosmic event 4.3 billion years ago, but you weren't there to prove it happened. Nor can you say that these things will occur if the moon wasn't around. Sad to have this hogwash be seen as "science" when none of it can be tested.
Second, who is to say that there were two sphere like planets swooping wildly around the sun's orbit when they crashed into one another. Due to the different density and material make up one began to from as Earth while the other became entrapped by the gravity of the over sized sphere which is "Earth" and after millions of years of colliding with one another the smaller sphere is what is now known as the moon?
See, what I did there? Pulled crap out of my ass to prove that all this is speculation and can't be proved!
Sure it's speculation, but that's what science is. The difference between what science is and the "pull crap out of your ass" speculation that you did is that scientists actually look at the consequences of their speculation. If their idea about lunar formation is right, there will be all kinds of observable consequences. The scientists who propose the idea then look at the actual data and see if it matches up with what their idea predicts will be observed. If it does, great, then the idea has evidential support and becomes part of the body of scientific knowledge. If observation doesn't match up (and this is the more important part), the idea gets rejected and the scientists must come up with a new idea.
That's the process of doing science. And that's what science is, a process. It's not a body of set-in-stone knowledge. That's more along the lines of what religion does, not science. If new observations come along that contradict a theory, then the theory will be modified or rejected.
Your pulled crap out of your ass idea has the flaw that data on the composition of the earth and moon does not match what you'd expect if your idea were true. Your idea relies on the earth and moon having different material makeup and different densities. They do not, so your idea is eliminated. Science eliminates things; it does not prove anything. Basically scientific "proof" is the process of ruling out competing ideas so that the consensus idea becomes accepted as the one that best matches the evidence. Yet even without absolute proof, the process seems to work pretty well, as evidenced (as just one example) by the means by which we are communicating.
Some people in this comment section need to re-evaluate their lives and go back to school.
"There is absolutely no way to prove your theories. "
There's absolutely no way to prove that there's an interior to a brick, since to see any interior we have to put energy in to breaking it, which energy "could" be forming the new surface.
We CAN prove the moon arose this way, by showing a model of the system that could create it and seeing if the model simulation is sufficient and reliable an explanation. Only if you're going to demand an arbitrary level of proof will this not work, and if you're going to do that, prove a solid has an interior, not just a series of surfaces.
Astonished that they were the only points you recognised as being the ones that stood out . Although I liked number 4 ,but I'm confused isn't the earth slowing it's rotation due to the recession of the moon ,about a inch every year ?. Astronomers have done some math on this and reversed the rotation ,and the moon hits earth around 1.27billion and if that's the case the moon would be ripping the iron out of any one living and causing a lot of chaos for anything to survive .it's come in to early for the evolution theory time frame. How does this fit in ?. Thank you .
Except you have forgotten that the rate of retreat isn't a constant.