Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Minus the Sun

  1. Apr 19, 2008 #1
    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...
     
  2. jcsd
  3. Apr 19, 2008 #2
    Global warming would be less of an issue.
     
  4. Apr 19, 2008 #3
    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.
     
  5. Apr 19, 2008 #4
    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...
     
  6. Apr 19, 2008 #5

    russ_watters

    User Avatar

    Staff: Mentor

    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.
    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.
     
    Last edited: Apr 19, 2008
  7. Apr 19, 2008 #6

    BobG

    User Avatar
    Science Advisor
    Homework Helper

    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.
     
    Last edited: Apr 19, 2008
  8. Apr 19, 2008 #7

    Astronuc

    User Avatar

    Staff: Mentor

    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.
     
    Last edited: Apr 19, 2008
  9. Apr 19, 2008 #8
    8 minutes. Tides are effected by the sun, too, aren't they?
     
  10. Apr 19, 2008 #9

    Mk

    User Avatar

    What about using geothermal heat to stay alive?
     
  11. Apr 19, 2008 #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.
     
  12. Apr 19, 2008 #11

    Danger

    User Avatar
    Gold Member

    Is anyone else getting flashbacks to 'Space:1999'?
     
  13. Apr 19, 2008 #12
    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.
     
  14. Apr 19, 2008 #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.
     
  15. Apr 19, 2008 #14
    Of coarse the initial response will be to stockpile garlic, and silver to help protect ourselves from the vampires.
     
  16. Apr 20, 2008 #15

    Chi Meson

    User Avatar
    Science Advisor
    Homework Helper

    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]
     
  17. Apr 20, 2008 #16

    wolram

    User Avatar
    Gold Member

    I will just buy some big sun lamps.
     
  18. Apr 20, 2008 #17

    Astronuc

    User Avatar

    Staff: Mentor

    Wait! I think you're being a tad bit optimistic there, Chi.

    I can't wait! :biggrin:
     
  19. Apr 20, 2008 #18

    Danger

    User Avatar
    Gold Member

    Where's Zaphod Beeblebrox when you really need him? :rolleyes:
     
  20. Apr 20, 2008 #19

    russ_watters

    User Avatar

    Staff: Mentor

    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.
    Yes, but not much. 10% maybe? (not sure exactly)
     
  21. Apr 20, 2008 #20

    russ_watters

    User Avatar

    Staff: Mentor

    We probably could if we had some notice, but if it was a surprise, we'd be dead before we could impliment it. And of course, the long term impact would be mass starvation...
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?



Similar Discussions: Minus the Sun
  1. The Sun is (Replies: 19)

  2. Sun dogs (Replies: 5)

  3. The Minus Dimensions (Replies: 3)

  4. Sun storm (Replies: 1)

Loading...