It is possible to write a novel in 30 days, and I'm living proof. I've done it. Twice.
Today is the start to National Novel Writing Month, or as it's more affectionately known "NaNoWriMo." The goal is to write a 50,000 word novel in only 30 days. It doesn't have to be perfect, or polished, or even coherent when you're finished, but it has to be 50,000 words.