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So let's say I have rogue planet the size of mars. I want seasons roughly the the same as Earth and a "sun" that appears similar to our sun from the surface.

How big would the Star need to be? How far away from the planet would it have to orbit?

I also want a moon. I'm thinking maybe 2 bodies of equal size orbiting on either side of the planet would work, but not sure...

Edit - The planet is in reality a space ship with an habitable exterior. The race is capable of artificial gravity and fusion. I Need a sun and moon object in the sky to replicate the appearance of an earth environ on the surface of the ship.

I need to know the minimal distance/size that i could make these from the ship to create the illusion.

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  • $\begingroup$ You should have the planet orbit the moon and then have the sun orbit the planet, but not the moon. That seems like it would work \s $\endgroup$ – ArtisticPhoenix Mar 7 '18 at 4:45
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    $\begingroup$ By definition a "rouge" planet is unbound, in otherwords its not bound to a sun, which is why its rouge. $\endgroup$ – ArtisticPhoenix Mar 7 '18 at 4:47
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    $\begingroup$ I'm confused. What's wrong with just having the ship orbit a sun when it doesn't need to move around? $\endgroup$ – Aify Mar 7 '18 at 7:42
  • $\begingroup$ Your original question made no mention of the goal you had (a sky like Earth for your ship inhabitants) or even of the "ship". This is such a drastic change you should close your question entirely and ask a completely new one (more carefully explained !). An edit is inappropriate in this case. $\endgroup$ – StephenG Mar 7 '18 at 15:46
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    $\begingroup$ I'm voting to close this question as off-topic because the edit is too drastic a change and would completely void the two existing answers made in good faith. $\endgroup$ – StephenG Mar 7 '18 at 15:48
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Any self sustaining star will be way more massive than Mars. This makes impossible for the star to orbit the planet: it will always be the planet to orbit the star.

Or, better, the center of mass of the system will always be deep into the star.

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Change your inertial frame of reference.

If you treat the Earth as a stationary object, then the Sun will be orbiting the Earth roughly once a day. This will make the math needed to explain the motion of the other planets much more complicated, because the motion of the planets will change from being roughly elliptical to a spiral-thing (as can be seen in this image).

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