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The question is pretty simple: what's the minimum distance that can be travelled via a Stargate? I know two stargates cannot operate in close proximity, such as on the same planet, as one Stargate will override the other, rendering it inoperable while the other is in use. But could you use a Stargate to create a wormhole between Mars and Earth (if there was one on Mars) for example?
My memory is a bit rusty on SGU, but it seemed the Destiny was pretty close to some of the planets they gated to from the Destiny after dropping out of FTL.