I need to borrow your brain-meat.

[Tev]

If a planet the size of Earth revolved around the sun in a North/South revolution while maintaining an East/West rotation.....what would the days and nights be like on said planet and would there be things like ice-caps or would the place be baked-semi evenly all year long?

I'm helping a friend come up with some new and interesting star clusters for a game he's trying to make and I'm trying to write up a description of an earth size habitable planet that would exist in such a system.

[Nikose Tyris]

If it was the same distance from the sun as earth, and the same size of planet? It would logically be cooler all over if it were... I'd need to model this in 3D to understand it. [Sith might be able to maths it faster and easier though.]

Assumptions that could be made would be lower overall temperature, with longer nights.

[Flarecobra]

Well, the seasons will be VERY extreme. An example of that style of rotation would be Uranus, as it has a very similar rotation angle.

And if he's looking to have life on said planet, then I'm afraid he'll be out of luck as I doubt it would be very kind to any sort of complex life.

<== *Student of Astronomy*


Anyway, you're asking about Earth-like planets... let's look at science fiction a bit. Many of them will have several things in common: They fall within a habitable zone of the star, of which it depends on the host star(s), and the moons. The moons will infuance the tidal forces, and how they regulate said forces.

[Osterbaum]

Make the planet have two large moons. I always thought what the Earth was missing was another moon.

[Azisien]

Universe Sandbox was on sale during the holidays. Let's set the Earth to this rotation and see what happens!

[Amake]

Well we do have the shifting seasons in our temperate zones due to the Earth's axis leaning at some 10-20° (I don't remember) compared to its orbit. This planet in contrast would have an exact 90° lean. Seems to me it would have every possible climate of Earth at every latitude during the course of a year, ranging from -80°C winters to +50 in the summer. Maybe a significantly elliptical orbit or an exceptionally long day could make things more interesting. . .

[Tev]

Well we do have the shifting seasons in our temperate zones due to the Earth's axis leaning at some 10-20° (I don't remember) compared to its orbit. This planet in contrast would have an exact 90° lean. Seems to me it would have every possible climate of Earth at every latitude during the course of a year, ranging from -80°C winters to +50 in the summer. Maybe a significantly elliptical orbit or an exceptionally long day could make things more interesting. . . See that's what I was wondering. Now I need to come up with what kind of critters and plants would manage to populate that kind of world.

I mean, they managed to stick life on that crazy Ice/Fire prison planet in Chronicles of Riddick after all....
http://images.wikia.com/riddick/images/f/fa/Applesauce.jpg

[Osterbaum]

You could have microbes and possibly even a few multicellular organisms. The multicellulars would propably have to live in areas with a more stable microenvironment, like hot air vents in the bottom of the sea. You could have some nematodes, annelids and maybe even crustaceans.

e: XTREME (http://www.calacademy.org/exhibits/xtremelife/life_on_earth.php)

[Doc ock rokc]

So it moves around the sun in a northward direction but the "earth" itself spins in a normal fashion? It wouldn't change anything except possibly suggesting that the core of the sun is unstable magnetically possibly causing extreme aurora

[Menarker]

Keep in mind that the axis upon which the earth spins is crucial. By which I mean the slant upon which it rotates.

For example, our Earth is technically closer to the sun during the WINTER time than the summer. But our weather is hotter during the summer because the sun's rays are more directly impacting the surface during that particular time of year.

[McTahr]

One problem is you're using a two-coordinate system to describe a three-coordinate (http://en.wikipedia.org/wiki/Cartesian_coordinate_system) situation. EWNS amounts to a two-coordinate plane and is mainly used because we roughly approximate the earth to be flat. (On maps! Because we're lazy and it's a fair approximation, really.)

To describe this appropriately I would highly recommend a rough sketch or a plotted coordinate system. Say: Suppose the sun is centered at the origin, (0, 0, 0) and a planet orbits in the Y-Z plane while revolving about its X axis. (This is roughly what you described sounds like in my head, but ultimately since you specified using EWNS it could also be revolving about the Z axis, technically.)

Or even describe it via the axis of the orbit/rotation. Are they parallel? Perpendicular?

Anyway, you also need a radius for the orbit, which essentially will establish a baseline, obviously the idea is a temperature range that will (mostly) allow liquid water to form (between 0-100°C). If we're assuming habitable implies roughly Earth/Mars-ish radius, then you still need to take into account the direction of the orbit. For the X-axis motion given above, days would not vary in length, while for the Z-axis rotation above, seasonal differences in lengths of days would potentially make particular areas uninhabitable or at least extreme (imagine if the days in summer never ended, and the nights in winter went on for the entire winter, more or less) at the poles, while the middle would have slightly less extreme variations. For the best explanation of all points, it really helps to model or at least visualize it.

Also eccentricity (http://en.wikipedia.org/wiki/Orbital_eccentricity) comes into play. How elliptical is the orbit? Necessarily a perfectly circular orbit means no seasonal difference, while a higher eccentricity or elliptical shape generates greater seasonal differences.

E- For an error, just woke up.

EE- Stillll editing because posting while sleep-retarded is dumb.

EEE- Okay maybe less dumb now.

[Nique]

This thread needs pictures.

[McTahr]

http://i57.photobucket.com/albums/g229/JimJimtheInfernalJanitor/Random%20NPF/blahhh.jpg

Shitty paint representation of the previous example. Note the orbit's centered around the X axis. Does your rotation line up parallel with that, or perpendicular, along the Z axis, or some angle between the two? Assuming no eccentricity, Z and Y rotations are intrinsically the same, essentially just bearing a different "start position". (Also, to help you visualize, earth! (http://en.wikipedia.org/wiki/File:AxialTiltObliquity.png), note that it's a slight variation of the Z axis revolution, where the axes of orbit and revolution are perpendicular, resulting in a less extreme example of the phenomena mentioned below re: uber long days/nights at certain locations.)

(For eccentricity, basically any habitable planet is going to be just barely above 0 or so. (Earth is 0.0167, Mercury around 0.2, the highest in our solar system, for reference.) 1 or greater essentially implies no orbit, just a para/hyperbolic curve.)

(Also for simplicity, obviously we define the coordinate system to have the orbit lie in a plane created by two of the axes. This does not inhibit other planet's orbits from not lining up with these planes, obviously. The gravitational pull between planets for the sake of science fiction can be ignored.)

[The Artist Formerly Known as Hawk]

Yeah, to sum up, the earth moves in wierd and complex ways that we mostly just ignore because it would screw up our calender and seasonal changes. To try to work out what a planet would be like that was tilted like earth, moved at the same speed through space, rotated at the same speed and direction, but which moved along a different axis would require a complex computer model to work out what it looked like, so trying to imagine it without that is kind've hard.

There was a show a few years ago where they tried to simulate an alien world that didn't spin at all, and the computer model they used suggested that life would only form along a broad span of the equator, and the northern hemisphere had a permanent super cyclone in it. It was wierd, but nobody could have predicted it before they ran the simulation.

[McTahr]

Yeah, basically anything I said is only a reasonable approximation if we're talking only minute differences in any direction from what we consider "standard" (re: earth).

You can make a reasonable-sounding guess out of all that, but that's about it.

[Osterbaum]

There was a show a few years ago where they tried to simulate an alien world that didn't spin at all, and the computer model they used suggested that life would only form along a broad span of the equator, and the northern hemisphere had a permanent super cyclone in it. It was wierd, but nobody could have predicted it before they ran the simulation.
Man, that would be one interesting planet to live on.

[Magus]

On a planet such as this, people would wear hats on their feet, and hamburgers would eat people.

It's just science.

[Aerozord]

There was a show a few years ago where they tried to simulate an alien world that didn't spin at all, and the computer model they used suggested that life would only form along a broad span of the equator, and the northern hemisphere had a permanent super cyclone in it. It was wierd, but nobody could have predicted it before they ran the simulation.

actually something I wanted to point out, our weather is powered by the sun, and one spot is getting most of the energy all year. If it was north pole (which is water), then you'd probably have a nightmarish storm sitting there. The south, which has land, possibly it would be a giant sand storm caused by dry land and intense wind.

Other side, the land would probably be very calm to the point I'm not sure life could exist even if it survived the cold. Wind, rain, and lightning have alot to do with the ecosystem and the dark side wouldn't see much. In any case life as we know it wouldn't exist there.

[Professor Smarmiarty]

Man water as a prerequistie for life is tots overrated. Liquid formamide is far more plausiable (by which I mean its much cooler while less plauisable). Cause hydroylsis eats all your RNA nom nom nom. Fucking water.

[Aerozord]

Man water as a prerequistie for life is tots overrated. Liquid formamide is far more plausiable (by which I mean its much cooler while less plauisable). Cause hydroylsis eats all your RNA nom nom nom. Fucking water.
water is still most prevalent solvent, so it would probably still be the basis of life on earth.

[Professor Smarmiarty]

It has little to do with needing a solvent. Most of the solvent based origins of life are pretty bullshit. Like the whole "primordial ooze" idea that was invented in the 50s- pretty much completely wrong on every level.
The most important issue is that if you are working in a solvent you'll need get the concentrations of things high enough to worl and also it's pretty hard to naturally build large things out of solvents. Most of the going theories these days either use pretty much all solids (ice is a common one) or a liquid/solid interface where the solid can extract the materials from the interface.
And like is water the most prevalent solvent? Like it is on earth but overall if I had to guess I would say its probably like methane or some shit.
Water is the wackiest solvent though. Like if you go to a party and theres some dude with a false moustache and suspenders that's water the crazy devil.
The fat dude is methane, fatty fatty.

[Aerozord]

And like is water the most prevalent solvent? Like it is on earth but overall if I had to guess I would say its probably like methane or some shit.

but, we are talking about Earth

[Professor Smarmiarty]

But a good chunk of life origin theories (and in my opinion all the best ones) don't start on earth.