Horizons Half Right Tidally Locked

[D.D.Hariman]

Ok,
They finally have the tidally locked planets half right.

I have now spent a few days on a tidally locked planet and never had the start go down but I have gotten to watch another star in the system move around in the sky. Kind'a neat.

BUT, I have also before this spent about a week on a different planet in the same system that was also listed as tidally locked and again the star never set which was an impossibility since that planet was half of a binary system that rotate around a common center so the star should have been moving around in the sky because the planets were actually tidally locked to each other even though the other planet was still moving around in the sky.

 

[Rooster Podunk]

Good to know someone else wonders about how it all works together. One reason I love exploring is looking at some of the crazy systems out there and trying to understand the mechanics (as best as this layman can). One planet in particular was in a binary system with the B star orbiting the A star but on a perpendicular axis. So one sun would cross this planet's sky East to West, while the other North to South. Then some systems are like all the balls from three pool tables were racked and broken at the same time. Rocks and ice cubes and gas giants in all kinds of crazy interactions.

 

[varonica]

Ok,
They finally have the tidally locked planets half right.

I have now spent a few days on a tidally locked planet and never had the start go down but I have gotten to watch another star in the system move around in the sky. Kind'a neat.

BUT, I have also before this spent about a week on a different planet in the same system that was also listed as tidally locked and again the star never set which was an impossibility since that planet was half of a binary system that rotate around a common center so the star should have been moving around in the sky because the planets were actually tidally locked to each other even though the other planet was still moving around in the sky.

Keep in mind that Elite also counts Resonance Locking (as in mercury) as Tidal Locking, so this can sometimes lead to strange occurrences. For instance if it is a 2:1 Resonance Lock it could still mean that one body always keeps the same face to the sun even in a binary setup while the other body moves around in the sky. For simple tidal locking the rotational and orbital period of both bodies should be the same, for resonance locking the two bodies will often have different rotational or orbital periods.

For a body by itself orbiting a star an identical orbital and rotation period should mean it always keeps the same face to the star, but mercury for instance is in a resonant lock with 3:2 period, so it rotates three times for every two orbits around the sun, this will be described in Elite as Tidal Locking, so its orbit and rotational period will be different.

 

[D.D.Hariman]

OK,, Now only maybe 1/3 right.
Got to watch a star rise on a tidally locked planet in the same system where the one is in my original post.

 

[Cmdr Nemo]

Keep in mind that Elite also counts Resonance Locking (as in mercury) as Tidal Locking, so this can sometimes lead to strange occurrences. For instance if it is a 2:1 Resonance Lock it could still mean that one body always keeps the same face to the sun even in a binary setup while the other body moves around in the sky. For simple tidal locking the rotational and orbital period of both bodies should be the same, for resonance locking the two bodies will often have different rotational or orbital periods.

For a body by itself orbiting a star an identical orbital and rotation period should mean it always keeps the same face to the star, but mercury for instance is in a resonant lock with 3:2 period, so it rotates three times for every two orbits around the sun, this will be described in Elite as Tidal Locking, so its orbit and rotational period will be different.

It's the same process our moon in realation to us is. The moons rotation is such that some 60 percent (plus or minus) is always visable to Earth and the other 40 is never visable.

 

[varonica]

It's the same process our moon in realation to us is. The moons rotation is such that some 60 percent (plus or minus) is always visable to Earth and the other 40 is never visable.

No, the moon has a wobble on it's axis caused by its elongated orbit that exposes areas called libration zones that would never otherwise be seen if it kept the exact same position, that's not the same as a resonance locked orbit. With a resonance locked orbit it would be quite possible to see entire surface of an orbiting body depending on what sort of resonance locking it was.