Why is the Earth's axis inclined 23.5 degrees from the perpendicular to the ecliptic plane?

Discussion in 'Off Topic' started by Random Variable, Nov 30, 2007.

  1. spidey07

    spidey07 No Lifer

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    Not only that, but probably no life. No currents, no winds, no water cycle no nothing.
     
  2. gururu2

    gururu2 Senior member

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    the perplexing thing about this is that your anus is also 98 degrees... fahrenheit
     
  3. Jeff7

    Jeff7 Lifer

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    I'll have to go with :confused: too. Then we'd wonder, "Why wasn't Earth whacked with various objects when it was forming?" Zephr, I think you missed the point of what I meant with my commentary.




    Check out Venus sometime. Or Jupiter. Very low angles of tilt. Jupiter's got an incredibly turbulent atmosphere, with many long-lived storms, and it's even farther from the Sun than Earth - so less energy input. Venus has low-level breezes on the surface, and windspeeds of a few hundred mph at the cloud tops.

    Maybe not life like we have right now, but something would likely arise to take advantage of the benefits of a lack of seasons.
    There'd be thermal inequalities anyway just from the uneven heating resulting from the changes in light's angle of incidence, simply due to the shape of a sphere. And Earth rotates - part of it cools, while part heats up. There would still be a constant attempt by the planet to reach thermal equilibrium, resulting in turbulence, and thus, wind and other fluidic currents.
    Even the simple action of heating the surface would induce air movement, as the warm surface air rises, only to cool and sink again.
     
  4. Shawn

    Shawn Lifer

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    There would still be life. Currents and winds and the water cycle would still occur because of the earth is spinning. Things would be very different though.
     
  5. Fritzo

    Fritzo Lifer

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    You're a little off there. Currents and winds are mostly caused by the sun's radiation. Tides (and to a point currents) and caused by the moon's pull. Tidal forces are seen as having the greatest impact on the creation and evolution of life.
     
  6. gururu2

    gururu2 Senior member

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    convection and gravity. winds and currents are very affected by the earths rotation otherwise the sun would only hit one spot of the earth... ever, leading to vast differences in water and air movement. this evolution of life business is just theory, I wouldnt use it to argue on it being dependent on earth rotation, tidal shifts, God's mood, symmetry of the universe, etc.

     
  7. rbV5

    rbV5 Lifer

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    It is changing. Currently, the angle is decreasing (>40,000 year period, 22.1° to 24.5° range)

    As the moon moves away (it is moving away from earth ~ 1 inch/year), the earth will lose the buffering effect of the moon's mass (keeps the angle tilt range narrow) so in ~ 2billion years, the tilt range will grow to a much wider ~ 27° and 60° for the period.
     
  8. Eeezee

    Eeezee Diamond Member

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    There is plenty of math to back it up, many simulations have been done. Most people just don't realize that Planetary Science is a real field with scientists actually working on problems like this one.

    Many planets have some sort of tilt. Angular momentum is a conserved quantity, and when several masses are clumped together to form a planet the sum of their angular momentum is also conserved (you basically add them all up and get a new vector). The Earth most likely always had a tilt.
     
  9. Eeezee

    Eeezee Diamond Member

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    There would likely still be seasons, just not as we know them. The temperature variance from the middle of the year to the beginning might be a few degrees at the most, since the Earth doesn't move in a perfectly circular orbit (it's just barely an ellipse, I know you know this but other ATOTers might not).
     
  10. Eeezee

    Eeezee Diamond Member

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    Does a change of temperature of an object influence its angular momentum? I'm pretty sure it doesn't (or if it does, it's negligible).
     
  11. DangerAardvark

    DangerAardvark Diamond Member

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    Pff, that's just the Earth gangsta leaning it's way around the sun.
     
  12. JulesMaximus

    JulesMaximus No Lifer

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    No no no, it's because God made it that way. There is no reason to question or research any further because of this known truth.
     
  13. Jeff7

    Jeff7 Lifer

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    No, God made Earth with its axis perfectly straight up and down. It's the rest of the Universe that's inclined.
     
  14. pmoa

    pmoa Platinum Member

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    prolly because of Chuck Norris' Roundhouse kick