Can’t you place a space elevator below or above the equator? The tether would leave the ground at an angle but it would be parallel to the centrifugal force from the planet’s spin.
In: Physics
It’s down to what’s at the other end of the space elevator, and where it is.
The tether would need to be attached to a satellite at geostationary orbit. In this orbit, the satellite would remain directly over the same point on earth all the time. And this orbit can only exist directly over the equator.
The tether, therefore, would also need to be attached at the equator, for two reasons:
– it’s the shortest distance to the satellite
– if it’s not on the equator and is, say, 100km North then the tether would be exerting a small sideways force on the satellite, trying to pull it out of the orbit a small bit. If the satellite were to be pulled out of the geostationary orbit then it would enter a geosynchronous orbit — it’s still over the same line of longitude, but from a viewpoint on earth would move slightly north and south in the sky. The tether isn’t going to let it move south and remain at the same altitude, so it would then start to get out of sync with it’s own orbit. This wouldn’t be good.
In short, if the tether was not on (or very close to) the equator then the satellite’s orbit could become somewhat chaotic.
Having some boosters on the satellite would help, but only for so long. Satellites in geostationary orbit still need to use boosters on occasion in order to fix their orbit if they start to wander. But having to over fix it because of the tether would use up more fuel.
Notwithstanding, the “satellite” here would be something massive anyway, like an asteroid — nothing man made. Also, in order to keep it in balance there would need to be something on the other side stretching out into space, with the same mass as the tether. But these are just nitty-gritty details…
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