1. SubscriberAThousandYoung
    All My Soldiers...
    tinyurl.com/y9ls7wbl
    Joined
    23 Aug '04
    Moves
    24791
    04 Mar '09 06:56
    Seasons are caused by the tilt of the Earth's axis of rotation. Now, imagine a planet which has an axis of rotation exactly perpendicular to the plane of it's orbit, yet still has seasons...how?

    The planet's orbit is not circular. It's elliptical. Therefore the planet is sometimes closer to it's sun, and sometimes farther, and the distance is significant enough to change the average temperature.

    As a result the equator experiences seasons, and there are two summers and two winters per revolution around the sun.

    Assuming the planet is otherwise like Earth, and the sun is like our Sun...

    Describe the ellipse necessary to create seasons comparable in average temperature to the ones we experience on Earth in the temperate zones.

    😕
  2. Standard memberleisurelysloth
    Man of Steel
    rushing to and fro
    Joined
    13 Aug '05
    Moves
    5930
    04 Mar '09 08:16
    Originally posted by AThousandYoung
    The planet's orbit is not circular. It's elliptical. Therefore the planet is sometimes closer to it's sun, and sometimes farther, and the distance is significant enough to change the average temperature.

    As a result the equator experiences seasons, and there are two summers and two winters per revolution around the sun.
    Two summer and two winters per revolution? Why?
  3. Joined
    02 Mar '06
    Moves
    17881
    04 Mar '09 08:35
    Originally posted by leisurelysloth
    Two summer and two winters per revolution? Why?
    only explanation i can think of is the sun is smack dab in the middle of the two focii? and so at the edges of the minor axis of the ellipse earth is experiencing summer, and at the ends of the major axis earth experiences winter? but i don't know the physics behind why earth would be traveling around a relatively "central" point in an elliptical orbit... seems counter-intuitive to me.
  4. Dublin
    Joined
    07 Feb '05
    Moves
    8158
    04 Mar '09 12:57
    Originally posted by Aetherael
    only explanation i can think of is the sun is smack dab in the middle of the two focii? and so at the edges of the minor axis of the ellipse earth is experiencing summer, and at the ends of the major axis earth experiences winter? but i don't know the physics behind why earth would be traveling around a relatively "central" point in an elliptical orbit... seems counter-intuitive to me.
    The sun is always at one of the foci, isn't it?
  5. Joined
    02 Mar '06
    Moves
    17881
    04 Mar '09 18:49
    Originally posted by Schumi
    The sun is always at one of the foci, isn't it?
    that's the way it should work, but then annually there would be a summer a winter, and two similar seasons resembling fall and spring... but the OP said there were supposed to be two winters and two summers so i was trying to construct a way in which this was possible.
  6. SubscriberAThousandYoung
    All My Soldiers...
    tinyurl.com/y9ls7wbl
    Joined
    23 Aug '04
    Moves
    24791
    04 Mar '09 20:00
    Originally posted by Schumi
    The sun is always at one of the foci, isn't it?
    I got this from some other forum, and the same thing was pointed out. OK. Forget the two summers and winters then.
  7. Joined
    12 Sep '07
    Moves
    2668
    22 Mar '09 02:46
    How about Terry Pratchett's Discworld?
  8. Standard memberwolfgang59
    howling mad
    In the den
    Joined
    09 Jun '07
    Moves
    45641
    23 Mar '09 21:58
    This is still a valid question. How eccentric would an orbit have to be to emulate the Earths tilt?

    Without googling I seem to remember that we get 5% extra energy at perigee which occurs in early January. How that affects climate/seasons I have no idea.

    Is the Earth as a whole warmer in JaN?

    Cooler in July?
Back to Top