Effects of solar eclipse spanning decades?

October 7, 2006 12:49 PM

Any ideas on the effects of a prolonged solar eclipse, say 10-30 years?

We are trying to theorise the possible effects a prolonged solar eclipse would have on the world if it spanned several decades: ie the biological/organic changes that may occur, as well as any immediate effects it may have to human society.

A few ideas/thoughts we had were.

- 'How quickly would the earths natural energy resources deplete without the aid of the sun?'
- 'Would this create an acceleration in certain organic forms evolving/adapting at an increased rate in order to survive?'
- 'How would this initially effect the human biological clock, ie the adjustment from night and day to one constant state.'
- 'Also what would the world look like when the eclipse was over?'
- 'Looking at the current state of quickly using up fossil fuels, if this eclipse was to occur what would be the alternatives for creating new energy sources? ie solar panels dont work with the sun'
- 'Would this bring on an ice age?'

Thank you for your time.

posted by Sevenupcan to science & nature (43 answers total)

Well, hell yes, it would create an ice age. Let's put it this way: The only thing that keeps this planet from being a frozen chunk of ice is the sun and the atmosphere. Without the sun, the atmosphere would quickly cool and the volatile compounds that we depend on for things like, oh, breathing would freeze, and at that point, there would be nothing keeping us from suffocating and dying. And then there's the whole freezing thing: There are very few strucutres on this planet that are capable of insulating humans from deep-space kind of cold. Fossil fuels aren't a concern anymore; you need to heat oxygen to feed into the intake of gas engines. Oxygen at this point is too precious and volatile to burn. Oh, and let's not forget working on the surface will become impossible. The atmosphere will freeze to the ground, and then simply stepping on a pool of frozen hydrogen with an imperfectly insulated boot will be enough to create a zero-friction surface. Joe Haldemann's "Forever War" has a great portion about working on the surface of Pluto that demonstrates the struggles we'd face.

Basically, unless we had a way to migrate a significant percentage of our technology and population FAR under the crust of the earth, and generate elecricity using nuclear sources, our goose is deep-frozen and the end is nigh within a year. Hell, Mars would be far more hospitable at that point.
posted by SpecialK at 12:57 PM on October 7, 2006

This question makes no sense.
-Eclipses CAN'T last for 10-30 years.
-Eclipses don't affect the entire world. They are a shadow cast on a small part of the Earth.

Do you mean, what would happen if all light from the Sun was somehow prevented from reaching any point on Earth? If that's the case, then we wouldn't last anywhere near 10-30 years. I don't feel like working through equations, but based on how quickly things cool off at night, I'm guessing that everyone on Earth would freeze to death in a matter of weeks.

On Preview, Special K is right (although I think that we'd be screwed in far less than a year).
posted by Humanzee at 1:01 PM on October 7, 2006

A solar eclipse is a localized phenomena. It does not block out all light to all parts of the earth. Diagram

Also... what you're talking about is impossible.
posted by cadastral at 1:07 PM on October 7, 2006

This older AskMe thread may be of some use.
posted by quin at 1:14 PM on October 7, 2006

It's theoretically possible. An object would have to be placed in L1 orbit, similar to the SOHO satellite, and it would have to be large enough to cast a shadow across the entire Earth.

This would get you closer to world domination than sharks with laser-beams, but to turn a profit you would have to demand a sum substantial larger than ONE MILLION DOLLARS.
posted by randomstriker at 1:37 PM on October 7, 2006 [1 favorite]

A parasol of sufficient size would be able to block out the sun. So would a large object co-orbiting the sun such that it would always be between us and the sun. Building a dyson sphere inside the orbit of the earth. There are lots of ways to have a permanent "eclipse."

I agree that freezing would be very rapid. After several years, only the very intelligent and the very primitive species (along with the expected set of parasites — dogs, wheat, cattle, etc) would still be alive. Life around ocean vents and life in geothermal-powered caves could live for many years, potentially. As mentioned, most atmospheric gas would freeze, but we would not run out of the stuff. We'd just have to shovel it into our warm caves. It would then thaw and sustain whatever biome we find to be sustainable. Friction was mentioned, but anyone from Canada knows you need good spikey boots in the winter.

I think a good cave located in a volcanically active area, with a robust mini-biome would be able to survive for decades. The hardest part would be maintaining a sufficiently large biome. Collapse of the environment would lead to immediate death for the entire colony.
posted by clord at 1:38 PM on October 7, 2006

BTW...given that Earth-Sun L1 is roughly 0.99 AU from the Sun (0.01 AU from the earth), the size of this doomsday device would have to be almost that of the Earth.
posted by randomstriker at 1:51 PM on October 7, 2006

"Do you mean, what would happen if all light from the Sun was somehow prevented from reaching any point on Earth"

Ok apologies for the way the question came out, maybe through an explanation i can propose why i have asked this.

Basically i am working on an a potential creative project, one idea is based around an event or events that has led to the sun being blocked from the earth (in some way) even if it be an exagerated (sci/fi) explanation. But i would like to try and include some essance of science fact to create a believable environment to base my characters in.

Im just looking for someone who can think outside of the box while applying some of the laws of the sciences. Thank you for your input so far, this has helped us re-evaluate possible ideas we already had.
posted by Sevenupcan at 1:59 PM on October 7, 2006

To a first approximation:

Everything on Earth would die.

Photosynthesis would stop, the food chain would cease, and then the world would become too cold for even the decay bacteria to function. After that, the atmosphere would freeze out.

All that would be left were microbes in the rocks and deep-vent ecosystems, and even they might freeze out without any insolation or become so small that they can't support anything other than microbes.

Small bands of humans could conceivably survive for a bit, but it seems unlikely. They'd be in conditions approximating outer space, and currently life in outer space requires a large-scale, high-tech industrial infrastructureto support it -- the few people on the ISS require a cast of thousands to keep them alive. Any survivors would only last until some critical part broke, and that would be it.
posted by ROU_Xenophobe at 2:05 PM on October 7, 2006

Basically i am working on an a potential creative project, one idea is based around an event or events that has led to the sun being blocked from the earth (in some way) even if it be an exagerated (sci/fi) explanation.

If you want anything like hard SF or remotely grounded in serious speculation, you're out of luck. You will not have characters for very long, because everyone will die. A few might have an adventure or two before something they need to keep alive stopped working, but even they would probably be dead in a few years.

If you want to pursue it, you should probably abandon any grounding in fact and go all-out silly. Edgar Rice Burroughs' books about John Carter on Mars might be good examples. Big, romantic, swashbuckling nonsense. Pale, elfin amazons living under the frozen surface with big eyes, pointy ears, who fight bravely against the frost monsters while wearing chain-mail bikinis. That sort of thing.
posted by ROU_Xenophobe at 2:14 PM on October 7, 2006

Here are some numbers to play with, which I'm almost certainly using completely incorrectly, as it's been a long time since I took a science class or converted a unit or, you know, did simple math without a calculator and furrowed brow.

The earth gets on average a bit less than 1 watt per square meter each day from the sun; if you somehow cut off all solar energy, we'd lose (roughly) that much energy every day.

24 watthour = 45 celsius heat unit, so to a very rough approximation the earth's surface would cool by 45C every day if you somehow magically eliminated all solar energy.

In real life the heat energy already held in the earth's mass would balance things out for a while, but if I'm figuring right (which I emphasize once again that I'm almost certainly not) we're talking about the atmosphere freezing into snow within a couple of weeks.

The "effect on the human biological clock" would be roughly that of a sledgehammer applied to a wristwatch. Repeatedly.

what would be the alternatives for creating new energy sources

Absolutely nil. It would take 1.7 billion such power plants to equal the energy coming to the Earth from the Sun".
posted by ook at 2:31 PM on October 7, 2006

Nuclear winter? Asteroid strikes? These can cause global clouds of dust that block sunlight from reaching the Earth's surface for years, and are much more plausible than actually putting something between the Earth and the Sun.
posted by nervestaple at 2:34 PM on October 7, 2006

Objects in the L1 point are not stable; the tendency is to fall out of the point. (L4 and L5 are stable; the other Lagrange points are not.) SOHO stays in the L1 point by constant use of steering rockets to correct its position.

If a natural object in the L1 point were large enough to fully screen the earth, then it would be too massive. The L1 point (and the other Lagrange points) only works if the satellite in it has negligible mass compared to the mass of the planet and star.

But even if you posit an "orbital parasol" in the L1 point, if it was large enough to fully screen the sun it would be torn apart by tidal stress from the Earth and the Moon. (A natural object large enough which was that close to the Earth would cause both the Earth and the object to tear themselves apart from tidal stress.)

I'm with ROU_Xenophobe: this idea is really not a good one.
posted by Steven C. Den Beste at 2:35 PM on October 7, 2006

I totally screwed up the definition of a celsius heat unit. Somebody who knows what they're talking about should take it from there.
posted by ook at 2:35 PM on October 7, 2006

This would almost certainly have to be a supernatural situation. An object blocking all light from the Sun would have to be bigger than the Earth (otherwise, part of the Earth would be in the penumbra). Building such a huge structure would be insanely difficult, and destroying it would almost certainly be easy. Anyone attempting such a feat would surely be better off destroying all life on Earth through some other means (for instance, taking their Earth-sized object and crashing it into the Earth).

On the plus side, if some maniac did attempt this (and somehow stopped earthlings from destroying the Sun-blocker), it would take so long that people could presumably build little "space stations" on the surface of the Earth. Nearly everyone on Earth would die off, but perhaps enough people could be saved to create characters for some sort of story.
posted by Humanzee at 2:37 PM on October 7, 2006

This is the sort of information I wanted to know. I'll admit if you haven't already figured by now, I know little of the known substance on eclipses and blockiads of the Sun. (friendly sarcasm)

From the flow of the discussion it seems that any object of measurable size that had the ability to block out the Sun would be "unbelievable" both scientifically and ecomocially.

So my next step is... "What is the largest known solar eclipse to have occured?" I'm presuming solar eclipses do vary in the amount of time they take to occur?

What would be the longest amount of time that one could possibly get a solar eclipse to last, and what factors would need to be present?

---

Thank you ook for the rough figures and ROU_Xenophobe for the references to the books.
posted by Sevenupcan at 3:01 PM on October 7, 2006

I'm with everybody saying that this would be a quick end to the species.

In addition, the heat from the sun is what fuels our global weather-cycles. As in, water evaporating into the atmosphere, condensing in clouds, and later raining (far from where the initial moisture was picked up). Same goes for the higher wind currents that drive lots of weather here in the US. You stop (or even just diminish) the suns rays, and you stop all that air and moisture circulating around, probably turning most continents into deserts and wastelands.

This would also affect most ocean currents, leading to loss of lots of fish species. But there would still be tides, provided the sun and moon are still out there sucking the oceans their way. So some minor tidal currents would likely remain. [Provided you've figured out a way to keep the oceans from turning into a gigantic ice-sculpture, that is].

Good luck with the SF--curious how it all works out!
posted by garfy3 at 3:10 PM on October 7, 2006

I'm with ROU_Xenophobe: this idea is really not a good one.

I didn't say it was a bad idea. You could write a really fun, pulpy treatment of this sort of thing. You could have a Mad Max kind of hero wandering through the ruins of the Earth in his Coldsmobile (rimshot), defending an occasional settlement of Hot Lesbian Ice Maidens against a marauding band of Vacuum Yetis, and then gettin' it on with 'em when they finally realize that they're not as lesbian as they thought. What is this thing you call love, stranger with big biceps?
posted by ROU_Xenophobe at 3:11 PM on October 7, 2006

The Black Cloud by Fred Hoyle considers just this (although it's not an eclipse but a superintelligent cloud that blocks out the sun for months). Hoyle was a Cambridge astrophysicist (best-known for his contrary opinions, but he did make very significant contributions), so I guess a lot of thought went into what the real effects would be. It's written in turgid, clichéd prose, but is at least a ripping yarn. Recommended.
posted by caek at 3:15 PM on October 7, 2006

Isn't this about as fanciful as asking what would happen if Earth were left on the outside of a Dyson Sphere or other Dyson construct (e.g. Stanford Torus/Ringworld)?
posted by bafflegab at 3:16 PM on October 7, 2006

I guess it's less of "what would happen" as opposed to "what extent (time and damage) would it happen till".

Thank you caek for the reference to Fred Hoyle's Black Cloud, strong chance of my buying this book even if it's for a good read.
posted by Sevenupcan at 3:36 PM on October 7, 2006

Incidentally, if you're looking for a Romantic treatment of this premise, check out Byron's Darkness (text). No science there, but it's fairly cheerful on the sociological front.
posted by Paragon at 3:39 PM on October 7, 2006

According to Wikipedia, the maximum duration of a solar eclipse is about 7 and a half minutes. This is of course the duration of the total eclipse as seen by an observer at one spot on Earth (the Moon's shadow traces out a path along the surface of the Earth).

Relevant factors include the distance between the Moon an the Earth (which varies at different points in the Moon's orbit), and the distance between the Sun and the Earth (which varies at different points in the Earth's orbit).
posted by Humanzee at 3:54 PM on October 7, 2006

If you were looking for something that would last 10-30 years, perhaps something that dimmed the sun (like a roving interstellar gas cloud that went between the sun and the Earth, or an H-fusion anticatalyst bomb launched into the heart of the sun by an old starfaring pirate-race who didn't like sunlight, or maybe galactic motion sweeping the Solar system into a part of the universe where the laws of physics are different) would be more interesting.

Then things would get colder, but not so cold as to be totally uninteresting.

None of those 3 ideas are original with me, by the way; I can think of at least two stories that have used each of them.
posted by ikkyu2 at 4:19 PM on October 7, 2006

If it helps anyone. The original idea was to have the world in darkness for enough period of time for it to have changed, yet still survivable, and then have a rebuilding of humanity afterwards, ie post-apocalyptic. It was just an idea.
posted by Sevenupcan at 4:39 PM on October 7, 2006

Isn't it possible we could create a bio-dome and keep it warm? Make sure we have a mega stash of uranium, nuclear reactors, and a ton of equipment to grow plants, etc..?
posted by wackybrit at 5:13 PM on October 7, 2006

Don't forget that the earths core can provide a lot of heat. Potentially, and so can radioactive materials. The biggest problem is that the freezing would happen really quick. before many people would have a chance to built support structures.

Maybe your story could revolve around people who came to the old biosphere with an old nuclear reactor scavenged from a sub.
posted by delmoi at 5:31 PM on October 7, 2006

The original idea was to have the world in darkness for enough period of time for it to have changed, yet still survivable, and then have a rebuilding of humanity afterwards

Then to my mind you don't have to decide why the world goes dark -- it just does. What the survivors do during and after the 'event' is the story. As well as how they explain it to themselves. Have fun!
posted by w_boodle at 5:32 PM on October 7, 2006

Well, one thing that could definitely achieve similar effects is volcanic winter. Also, check out the Toba catastrophe theory and the year without a summer.
posted by Humanzee at 5:32 PM on October 7, 2006

Check out Asimov's Nightfall. A good story about the effects of an eclipse-caused apocalypse, though not set on Earth.
posted by Upton O'Good at 7:27 PM on October 7, 2006

A parasol would be a great idea. Imagine in the near future, we put up a parasol in an attempt to screen out just enough sunlight to counter-act global warming... but something goes horribly wrong with the calculations. The planet is cast into a sudden ice-age, and we loose the ability to take down the parasol.

That would be entertaining "realistic" sci-fi, which ties in current events, and has a message about messing with the environment.
posted by clord at 7:32 PM on October 7, 2006

Anyone fancy a Pail of Air?
posted by codswallop at 8:01 PM on October 7, 2006

This is a very old idea in SF and the aftermath tale been done before, most notably around 50 years ago in Fritz Leiber's A Pail of Air. You can find the freezing earth as a theme going back right into late and mid-19th century SF stories. They are quite picturesque.

The best modern description of an absolutely frigid ice age descending on a planet that I've read was Helliconia Winter by Brian Aldiss. Helliconia is a planet in a multiple star system with a convoluted orbit that produces "great cycles" of thousands of years of antarctic conditions interspersed with a millenial springs and summers. The ecology oscillates and the top predator position is exchanged between the human-like warm inhabitants and the less-human and quite shaggy cold inhabitants. Many of the animals (including the humans) oscillate between several forms adapted for either warm or cold eras. Their transformations are triggered by global retroviral pandemics that perform massive gene expression reconfigurations. The human-like civilisation tends to get quite advanced before being wiped out by plague and the remaining population transformed.

Then there was the more recent Vernor Vinge A Deepness in the Sky, with arachnid-like organisms at roughly early 20th century tech levels that hibernate when their planet goes cold and their atmosphere freezes out. It has quite a well done description of some of the arachnids emerging in the middle of their hibernation and usingwhat is basically early 20th century-level deep-sea diving tech to navigate across the landscape on a mission. They also watch unknown and very advanced humans fighting a baffling war in orbit.
posted by meehawl at 8:12 PM on October 7, 2006

Your most plausible situation would be a big interstellar dust cloud, I think. But the drama you're looking for isn't really plausible, assuming what you want is near total darkness. That level of a diminishing of the Sun's light to the Earth would freeze the atmosphere within the timescale of your narrative, I'm guessing (but am not sure). A more realistically survivable diminishment wouldn't be as dramatic as near-complete darkness. You'd really only need something like a 20% reduction in insolation to quickly cause the kind of extremely deep ice age you're looking for.
posted by Ethereal Bligh at 8:41 PM on October 7, 2006

The easiest and most plausible way to get what you're talking about is dust in the atmosphere. Three ways to do it: a massive nuclear exchange, or a monstrous volcanic eruption (e.g. the Yellowstone caldera goes up) or an asteroid strike (like the one which killed the dinosaurs).

The first chapter of the book "T. Rex and the Crater of Doom" by Walter Alvarez describes what is thought to have happened in the months and years after the asteroid strike which marked the end of the Cretaceous era. It includes an extended period of frozen darkness (several years) as a result of dust in the atmosphere.

For your purposes, the nice thing about all of these is that they can be tuned to fit the story you want to tell. You can control the size of the asteroid, for instance, to calibrate the damage done by it. Or you can control the length of the eruptive period of the supervolcano, or the number of nuclear weapons used. (Of course, none of them would be remotely nice to live through in the real world.)
posted by Steven C. Den Beste at 12:55 AM on October 8, 2006

Interstellar dust isn't an answer. It's opaque when measured in light years. It's completely transparent when measured in AU's; you can't even tell it's there. It's like fog. Even in thick fog you can easily see your hands, right? And street lights if you're directly under them?
posted by Steven C. Den Beste at 12:57 AM on October 8, 2006

You're all crazy. You don't need a big thing to stand in the way of the Sun. That's what the other side of the Earth is for! Just come up with a catastrophe that causes the Earth to rotate like the moon. One day per one year. Half the Earth sunny and bright at all times, the other half shrouded in darkness forever. Half the population living a life of tropical bliss, the other half stuck in chill and cold and darkness. You think the sunny half will let the shady half come over, even for hot dogs and beer?

Oh hell no.

There. That one was for free. More will cost you.
posted by incessant at 3:57 AM on October 8, 2006

If the earth's period of rotation changed that drastically in such a short period of time, the energy release would melt the crust of the planet.
posted by Steven C. Den Beste at 5:56 AM on October 8, 2006

incessant: The lit side will be warmer, but the atmosphere will still transfer heat to the unlit side. Depending on how thick the atmosphere was, life on the dark side might not be so bad. A lot of planets in very small orbits around other stars rotate synchronously, so this topic has been explored in the astrophysics literature.
posted by lukemeister at 6:55 AM on October 8, 2006

Yeah, you guys are right, I'm crazy-thinking. Sorry! Sevenupcan, go back to your totally believable and completely scientific idea! Guess my brainstorm was ridiculoso!

See, lukemeister, if life on the dark side isn't so bad, then maybe it wouldn't be entirely outrageous that life had survived on both sides. But seriously, how bad does life have to be for you to want to live on the sunny side instead?
posted by incessant at 9:51 AM on October 8, 2006

You wouldn't want to live on either side. The only place that would be remotely habitable would be the at the border between the sunny side and the dark side, but since the planetary ecology would be totally disrupted you wouldn't last long (since the oxygen would run out).
posted by Steven C. Den Beste at 11:04 AM on October 8, 2006

You should also read Spin, or at least pass your ideas through someone who has.
posted by Coda at 7:16 PM on October 8, 2006

Isn't the start of Spin a bit like Greg Egan's Quarantine or what? (stars go out, earth's in a bubble, EVERBODY PANIC!)
posted by meehawl at 10:52 AM on October 13, 2006