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108

In theory, the answer is actually yes. However, unlike our own planet, whose seasons are created through tilt, the planet in question would have to have an elliptical orbit that brought it closer to its sun during certain parts of the year and further away during other parts of the year. The regularity of the orbit would create stable season times. This ...


57

An even simpler explanation is simply for there to be no land in one hemisphere of the planet. If it’s summer in the southern hemisphere, then no one will care that it’s winter in the northern hemisphere if there is no land and therefore no people. Seasons will be stated as affecting the whole planet even if it’s not technically true. They might affect a few ...


49

Yes and no. This NASA page has a good summary of why we have seasons (emphasis mine): It is true that Earth’s orbit is not a perfect circle. It is a bit lop-sided. During part of the year, Earth is closer to the Sun than at other times. However, in the Northern Hemisphere, we are having winter when Earth is closest to the Sun and summer when it is farthest ...


41

Yes it is possible, if the planet has little axial tilt but an eccentric orbit. Then summer will be when it is closest to its sun, and winter will be when it is furthest away, which will be the same all over the planet — at the equator as well as in higher northern and southern latitudes.


35

I'm surprised no one mentioned Sitnikov planets yet. Image found on Wikipedia. There is a very unlikely constellation in which a planet moves along the axis through the centre of gravity of a binary star system. In such a system, the planet can oscillate chaotically which, given a tilted rotation axis of the planet, would lead to seasons of varying length. ...


30

The reason we have four seasons is directly related to our planet's axial tilt... the rotational axis of the Earth is currently [1] inclined at 23.5° from the "vertical" relative to our orbital plane: Summer is the season in which a given hemisphere is tilted more towards the sun, Winter is the season in which a given hemisphere is tilted away, and Spring ...


26

Get rid of the "gathers" part of "hunter-gather" and make the people to be carnivorous; At least like wolves are, if not obligate carnivores. That would greatly increase the gap between where agriculture becomes more advantageous than a nomadic hunting/herding lifestyle. Most likely they would still pick up skill and knowledge to care for the herd, and ...


20

An alternate explanation would be a binary star system. While the two stars orbit eachother, they get closer and further away from the planet, producing more and less heat. This allows for seasons of equal length, while an elliptical orbit would have a short warm season, and a longer cold season, as the orbital velocity of the planet is greatest at its ...


19

Altitude. The big island of Hawaii has just about every climate type. Discussed here: Could an island on Earth with these climate types exist? It is a combination of the giant central mountain intercepting rain clouds (and thus a dry side and a wet side) and the ability of higher altitude to simulate higher latitude. Higher is colder. Put your land in the ...


18

Imagine a planet with two life layers: Outer space ... Rather dense atmosphere with floating moss performing photosythesis ... Hard earth crust, with not enough light for efficient photosynthesis Every once in a while, a huge (Paris-sized) lump of moss gets too heavy and falls down, triggering all herbivore animals 1000 kilometers around to wake up from ...


18

The planet has no axial tilt. But it anyway has seasons, because: The star it orbits arount is an intrinsic variable star, it changes its size and brightness periodically, causing seasons that may repeat multiple times per year, since the star may change its brightness multiple times per year. Variable star at different times: therefore, differing from ...


17

Sure you could have an erratic orbit. This is an orbit that has the planet coming sigifigantly closer to the sun at one point and then much further at its opposite but that the orbit is moving as well. In this way you could have a winter that is much longer than another and then a very long summer. This would be predictable once you understand the physics ...


17

I think that because of how orbital mechanis work, a planet with an aphelion inside the habitable zone and a perihelion too close to the sun would be better for life. A planet spends a lot more time near its aphelion than near its perihelion. Thus this planet would have moderate weather most of time and scorching weather during a short "season", instead of a ...


16

Yes, if the orbit isn't circular. Seasons can definitely occur on a tidally locked planet. Just like normal planets, tidally-locked planets don't need to have perfectly circular orbits. This means that over the course of a single orbit, this planet would receive different amounts of light from the star as it slowly moves away and then towards it. This will ...


15

The year is related to the motion of the planet around its star. When the star are back to a certain position, one says 1 year has passed. To account for season length which are in the range you ask, you could have a sort of variable star with small variation of intrinsic luminosity on an irregular period. When the luminosity is at its peak, you have the ...


15

Of course. Just make sure the axial tilt is zero. Basically, 99% of our weather changes are due to the angle of solar incidence, and only a small amount is due to the distance Earth is from the Sun (elliptical orbit). Earth's axial tilt is roughly 23.44 degrees. For a given latitude, a little trigonometry will show how the angle of solar incidence (draw ...


14

I'll offer a substantially different approach from what has been said so far. The orbit of your planet doesn't necessarily need to be eccentric or instable and neither does it need a rapidly oscillating axis of rotation. The cause of these fluctuations in temperature could be similar to our earth's ENSO which is a global phenomenon where the surface ...


14

To avoid too much confusion I am going to state some of my assumptions. I had to edit my answer slightly, to take into account some factors I had realised over the few hours since I posted my original answer. If people don't agree, I can always roll back. I still hold by my answer, although I do think altitude will actually be the biggest factor affecting ...


13

Co-orbital configuration It is possible for a planet to change its orbit every so often, resulting in the length of a year changing. This is just one more example among the many answers here of something that could cause seasons to lengthen and shorten in a cycle. An example of a planet that has this property is the Earth. Our planet is in a co-orbital ...


13

The four seasons are a convention which works best at temperate latitudes in Europe and the Americas. Our ancestors could have as easily agreed on six or eight. In many temperate and temperate-continental places there is actually a clear difference between the first part of what is usually called autumn and the second part: that would make five. In my ...


13

Your seasons aren’t caused by axial tilt. They’re more accurately known as ‘weather’. There is a system on Earth that leads to warm, humid seasonality and raised sea levels on top of the usual four seasons caused by tilt relative to the sun. It is called El Niño/ La Niña, and (to simplify greatly) it's a giant wave that bounces up and down the planet’s ...


13

The ocean itself tends to moderate climate -- Vancouver, BC, gets much less severe winters than Toronto, despite being somewhat further from the equator. Further, the temperature of the water has a strong effect -- Sheffield (England) would have a climate like Yellowknife if not for the tail end of the Gulf Stream warming the winters. So, that's what you ...


13

On such a planet life would probably evolve in different ways than on our planet, and complex life could be different from what we consider as "plants" and "animals". There would be a huge evolutionary pressure for a much more efficient hibernation than we have in real life, or if the conditions are even more extreme, then life could thrive while in the ...


12

First it needs to be noted, that for the entire planet to have same season it needs to have its rotational axis be perpendicular to its orbital plane. As for how it can have changing seasons there're a couple ways: Previously mentioned in one of the answers elliptic orbit. For earth-like seasonal difference the furthest point should be maybe 1.4 times ...


12

Yes Expanding on the other answers here, let's start with an overview of why there are seasons. I really like this description: We have seasons because the earth is tilted (wonky) as it makes its yearly journey around the sun. The Earth's axis is tilted at an angle of 23.5 degrees. This means that the Earth is always "pointing" to one side as it ...


11

There are several options (as detailed by the answers on this page), but one of the most possible with an Earth-like set-up, is an eccentric orbit heavily affected by surrounding planets and the planet's sun. The majority of this post is a reference from Dr. Irv. Boomberg, of the University of Toronto, Canada, from this page, of special interest is this ...


11

A meta answer for any question of the form "How can I have a planet where civilization doesn't look like ours?" is "Read Jared Diamond's book Guns, Germs and Steel and figure out what links to cut to stop us developing as we did. Our agriculture is primarily based around a very few grains (wheat, rice and, to a lesser extent, barley, maize and millet) and a ...


11

I'm going to attack this with math. First off, I am not going to make any assumptions about what orbits might be stable. That is something we can check with an orbit simulator like rebound, as I did in this question. Instead, I will assume there is a stable orbit around two suns of equal mass and luminosity. The orbital profile will be a perfect circle (0 ...


11

The mountain folk use an older calendar. The Julian calendar was introduced in the time of the Roman Empire and was adopted throughout the western world. In 1582 the Pope introduced a revised calendar called the Gregorian calendar, and over the ensuing centuries this calendar supplanted the older Julian calendar. Except where it didn't. The Berbers in ...


10

Make it long Chile is almost like that, except it is attached to a larger land mass and it has 3x the land area of UK. But since it spans a lot of latitudes, it naturally has polar climate at the south and deserts on its northmost areas, with some tropical pockets in between. It also has the world's second highest mountain range to the East, so it has a lot ...


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