What Would Happen if the Sun Suddenly Stopped Emitting Energy?

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Discussion Overview

The discussion explores the hypothetical scenario of the Sun suddenly ceasing to emit energy, examining the potential consequences for Earth and its inhabitants. Topics include atmospheric retention of heat, gravitational effects, survival strategies, and the fate of celestial bodies.

Discussion Character

  • Exploratory
  • Debate/contested
  • Conceptual clarification
  • Technical explanation

Main Points Raised

  • Some participants speculate on how long Earth's atmosphere would retain heat before freezing conditions set in.
  • There are differing views on whether Earth would drift away from its current trajectory without the Sun's gravitational pull, with some suggesting it would not notice immediate changes.
  • One participant proposes that if the Sun disappeared, the moon would not crash into Earth, as it orbits the planet independently of the Sun's gravity.
  • Participants discuss the potential for using artificial light and geothermal heat to sustain life in the absence of sunlight.
  • Some suggest that underground cities powered by nuclear or geothermal energy could be a solution for survival.
  • There are humorous and speculative contributions about the fate of other celestial bodies, including the collision of Jupiter and Saturn and the creation of a new star.
  • One participant humorously mentions stockpiling garlic and silver to protect against vampires, indicating a light-hearted tone in parts of the discussion.

Areas of Agreement / Disagreement

Participants express a range of views with no clear consensus on the outcomes of the scenario. Many ideas are speculative and explore various survival strategies, while some participants challenge or refine earlier claims without reaching agreement.

Contextual Notes

Participants mention various assumptions, such as the rate of cooling and the effects of gravitational changes, but these remain unresolved. The discussion includes a mix of serious and humorous contributions, reflecting a broad range of perspectives.

Who May Find This Useful

Readers interested in theoretical physics, astronomy, survival strategies in extreme scenarios, or speculative discussions about the future of humanity may find this thread engaging.

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Just sitting around BS'ing with a couple of friends this morning about the solar system and gravitational balance- and I began to wonder how long the Earth and its inhabitants would last if the sun suddenly quit emitting energy.

How long would our atmosphere retain enough heat to keep us from freezing to death?
Would we just fly off into another part of our galaxy without its gravitational pull?
Would the moon come crashing into us?

Hmmmmmmmmmmmmm...
 
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Global warming would be less of an issue.
 
pinestone said:
Just sitting around BS'ing with a couple of friends this morning about the solar system and gravitational balance- and I began to wonder how long the Earth and its inhabitants would last if the sun suddenly quit emitting energy.

How long would our atmosphere retain enough heat to keep us from freezing to death?
Would we just fly off into another part of our galaxy without its gravitational pull?
Would the moon come crashing into us?

Hmmmmmmmmmmmmm...

I suspect we'd all be dead in a few days.

Without gravitational pull of the sun we'd probably end up plunging off into a randomish course, but we'd all be dead before this made much difference to anything.
 
Probably if we knew it was coming we could survive longer. Most of our power is not generated from the sun, and artificial light could be used to grow food...
 
pinestone said:
Just sitting around BS'ing with a couple of friends this morning about the solar system and gravitational balance- and I began to wonder how long the Earth and its inhabitants would last if the sun suddenly quit emitting energy.

How long would our atmosphere retain enough heat to keep us from freezing to death?
Well, at night the temperature typically drops 30 degrees. That'll slow down after a while, but still, a few days of that and the Earth would be uninhabitably cold.
Would we just fly off into another part of our galaxy without its gravitational pull?
Would the moon come crashing into us?
Gravitationally, if the sun suddenly ceased to exist, we wouldn't notice anything except that after a little while (hours? days?) other objects in space (stars, planets, deep space probes) would be in the wrong place.

The moon orbits the Earth - it wouldn't fall to Earth if the sun disappeared.
 
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pinestone said:
How long would our atmosphere retain enough heat to keep us from freezing to death?

Use Newton's cooling equation. You'd need to set a minimum survivable temperature. You'd also need to settle on a coefficient of cooling. The second would be hard. You'd use one for heat radiated from the atmosphere into space. But, at the same time, the oceans and land would add some heat to the atmosphere as they cooled (using the same equation, except the surrounding temperature of the atmosphere would be constantly changing).

Considering how fast the temperature drops between daytime and nightime, it wouldn't take very long. The only difference is that the Earth would never have a day time to warm back up. In fact, rather than calculating an accurate model, the drop from daytime temp to night time temp might provide a decent rough estimate for the cooling coefficient.

As russ noted, the stars would be in the wrong place. They'd be off by about 1 degree per day. In other words, instead of shifting day by day the way they're supposed to, they'd maintain a constant location relative to the time of day.

We'd be dead long before we moved far enough to notice the constellations actually changing shape.
 
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One hemisphere (whichever one had winter) would continue to cool off, while the hemisphere with the sun, would lag in temperature by 12-24 hrs or so.

I imagine the side that was at night would get pretty darn cold - pretty quick and there would probably be high winds while the colder parts of the atmosphere condensed ahead of the rest.

The temperature dropped about 20°C in 6 hrs yesterday between mid afternoon (~1500) to 2100. I've had the house cool off from 68° to 40° F in a few hours during the winter when we lost power.
 
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russ_watters said:
Gravitationally, if the sun suddenly ceased to exist, we wouldn't notice anything except that after a little while (hours? days?) other objects in space (stars, planets, deep space probes) would be in the wrong place.

8 minutes. Tides are effected by the sun, too, aren't they?
 
What about using geothermal heat to stay alive?
 
  • #10
All of our plants would die, and no longer supply us with 02. We would need to build huge underground cities that used nuclear power/geothermal for heat and energy. We would probably be forced to use water for fuel and oxygen. I think man would survive, for a while, but the population size would be much much smaller.
 
  • #11
Is anyone else getting flashbacks to 'Space:1999'?
 
  • #12
W3pcq said:
All of our plants would die, and no longer supply us with 02.
Sun disappears! Women and minorities hardest hit. Film at 11:00.

I'm not sure what burrowing underground would buy us. I should think we could build insulated buildings more easily. The greenhouse effect and the loss of the ozone layer wouldn't be problems any more.

We would have to find some way to rescue the plants. We would run out of canned goods too quickly otherwise. We would have to design a self-sustaining ecosystem with us in it. One that is not based on unreliable sources of energy like the ephemeral Sun. I see this as a weakness in the Liberal agenda.
 
  • #13
Jupiter and Saturn will collide as they would be the two massive objects gravitationally attracted to each other. The other gas planets would soon join and then we would have enough mass to ignite and create a little dwarf star and voila! Earth will have a new body to orbit again.

And before our energy reserves deplete, we would hopefully refine our helium 3 reactors technology and use it to process helium 3 fusion and we could use the space shuttle to transport the fuel from its source (the moon) back to earth.

We will all live indoors and in underground corridors we would build to connect every building so that we could avoid the frigid cold outside. At least until we can build gigantic heat exchangers to warm up our air.
 
  • #14
Of coarse the initial response will be to stockpile garlic, and silver to help protect ourselves from the vampires.
 
  • #15
makethings said:
Jupiter and Saturn will collide as they would be the two massive objects gravitationally attracted to each other. The other gas planets would soon join and then we would have enough mass to ignite and create a little dwarf star and voila! Earth will have a new body to orbit again.

And before our energy reserves deplete, we would hopefully refine our helium 3 reactors technology and use it to process helium 3 fusion and we could use the space shuttle to transport the fuel from its source (the moon) back to earth.

We will all live indoors and in underground corridors we would build to connect every building so that we could avoid the frigid cold outside. At least until we can build gigantic heat exchangers to warm up our air.

Yes, that is exactly what will happen. Luckily we will have the help of the Xarganthian Empire, but they will later betray us and sell the property of our planet to the Endlochiarghs. We will then be shipped off to the Chruptan quadrant of the galaxy where we will be kept in cryogenic pods for 74 centuries as the Chrupto-Endlochiarghs work through the legal wranglings of the import. Finally an emergency will necessitate our thawing as an encroachment of the tyrant Sahddahm Huhseihn draws nigh. The certainty of the existence of innumerable weapons of negative-mass destruction completes the decision to send the humans in as cannon-fodder as the attack upon the Eirackee Empire ensues.

Tune in next week for the next chapter...

[all in good fun makethings, all in good fun]
 
  • #16
I will just buy some big sun lamps.
 
  • #17
Chi Meson said:
Yes, that is exactly what will happen. Luckily we will have the help of the Xarganthian Empire, but they will later betray us and sell the property of our planet to the Endlochiarghs. We will then be shipped off to the Chruptan quadrant of the galaxy where we will be kept in cryogenic pods for 74 centuries as the Chrupto-Endlochiarghs work through the legal wranglings of the import. Finally an emergency will necessitate our thawing as an encroachment of the tyrant Sahddahm Huhseihn draws nigh. The certainty of the existence of innumerable weapons of negative-mass destruction completes the decision to send the humans in as cannon-fodder as the attack upon the Eirackee Empire ensues.
Wait! I think you're being a tad bit optimistic there, Chi.

Tune in next week for the next chapter...

[all in good fun makethings, all in good fun]
I can't wait! :biggrin:
 
  • #18
Where's Zaphod Beeblebrox when you really need him? :rolleyes:
 
  • #19
Poop-Loops said:
8 minutes.
It would be 8 minutes before we'd start moving off in a tangent, but unless you had a telescope pointed at a star or planet at high magnification, you wouldn't notice for much longer.
Tides are effected by the sun, too, aren't they?
Yes, but not much. 10% maybe? (not sure exactly)
 
  • #20
Mk said:
What about using geothermal heat to stay alive?
We probably could if we had some notice, but if it was a surprise, we'd be dead before we could implement it. And of course, the long term impact would be mass starvation...
 
  • #21
I'm sure fema has a plan
everthing will be fine
 
  • #22
frogman said:
I'm sure fema has a plan
So do PETA and NASCAR... won't do any good, though.
 
  • #23
russ_watters said:
It would be 8 minutes before we'd start moving off in a tangent, but unless you had a telescope pointed at a star or planet at high magnification, you wouldn't notice for much longer.

Tides.
 
  • #24
Yeah, I'm thinkin' the cold would get us in just a few days. Project the natural nighttime drop in temperature forward in time and you get to freezing temperatures pretty quick.
 
  • #25
Depending on the temperature at which the cooldown starts, figure about 3 K/hr cool down. So in 96 hrs (4 days), is down about -288 K - below the boiling point of hydrogen.

However, heat from the Earth may keep the Earth surface above that point for a while.


Surface water would freeze, so would most liquids. So there would be no transportation after about 2-3 days, and no electricity, because power plants require heat exchage with the environment.
 
  • #26
Mk said:
What about using geothermal heat to stay alive?

About 99.98% of the Earth's energy is received from the Sun. Geothermal provides about 0.013% and tidal energy about 0.002%.

Since about 30% of the Sun's energy is reflected, you could increase the effective percentage of geothermal and tidal energy a bit, but they still essentially add to about zero.

You could concentrate a very small portion of the population around sources of geothermal energy and increase the release of thermal energy to some extent, but nearly the entire population of the world would have no source of energy (except that which was stored in the Earth as oil, natural gas, etc).

Earth's energy budget: http://en.wikipedia.org/wiki/Earth's_energy_budget
Earth's energy budget: http://eosweb.larc.nasa.gov/EDDOCS/radiation_facts.html
 
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  • #27
I don't see why everyone makes such a big deal out of this, there are other stars out there we could use :D
 
  • #28
NeoDevin said:
I don't see why everyone makes such a big deal out of this, there are other stars out there we could use :D

Start rowing!

[imagines huge oars sticking out the sides of the earth]
 
  • #29
just get everyone onto one side of the planet, and start jumping up and down to force it to go in whatever direction we want.
 
  • #30
We do have about 30,000 nukes waiting to be used. Just bunch them up on one side of the Earth (I know the location 99% of people reading this will have in mind) and let rip towards Alpha Centuari.
 

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