As others have pointed out, you wouldn't need to describe a human to a molecular level. You could create a biological clone using just the DNA- the human genome is some 24 gigabits (3 gigabytes?). That'd be something like "a few hours" to transfer over a standard home internet connection. Arguably, there are big chunks of that genome which will be common across individuals, so you wouldn't even need to transmit the whole thing every time.
Transferring a human's consciousness would be more difficult. As far as I'm aware, there are no serious estimates as to how "big", in bits/bytes terms, the human consciousness might be. Even if you could scan one, and it was a reasonable size for transmission, I can't even imagine how you'd go about "implanting it" into another human body (e.g. a clone). Without that, there's no "I'll just download into a Martian clone and have an explore".