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human
[Star Trek] What are the transporter's limits?

Throughout the various shows, films, and shorts, the transporter is often shown as being capeable of transporting people of various races, and objects of various sizes. This process is often explained as breaking something down to it's atomic structure, and then reassembling said structure in another location.

What I'm curious to find out (if people more knowledgeable about Star Trek have any idea), is does it have set limits? Like if I wanted to transport an entire planet, and all the people on it, could I do it if I had suficcient power to do so? And if I could do it, how far could I transport it? 

I'm assuming that there are some limits, otherwise why couldn't Voyager simply get transported closer to home?
gpt
There are several limits:

* Range: You can beam down to a planet from orbit, but you can't beam across a star system.
* Size: Something needs to be small enough to fit on a transporter pad. "Site to site" transports without a pad are a bit of a misnomer, they're actually 2 different transports where they first beam you to a pad, then to sickbay or wheverever you need to go.
* Power: Transporters take a lot of power. Transporting a handful of personnel here and there is nothing to a starship, but transporting a lot of stuff begins to strain their power.
* Cooldown: It actually takes the transporter some time to charge up between transports. We never see this because it's "precharged" when they step on the pad, but if they need to transport  two sets of people it takes a while for the transporter to recharge. Transporters are super fast for a small group but if transporting a large number of people or a large volume of cargo shuttles are actually faster.
* Warp speed: Transporting to and from ships moving at warp is not  technically impossible but *very* different. Even Montgomery Scott, one of the most brilliant engineers in Starfleet, had trouble with it.