Terra Nova may not be debuting until the fall, but Fox has a new promo to tide you over. "Welcome to Terra Nova folks. Welcome home." Terra Nova was originally slated for a special two-night preview on Fox in late May, but it was announced earlier this month that the ambitious Steven Spielberg -produced project would be pushed so the visual effects would have ample time "to be realized." Watch the trailer after the Jump... The show begins in the year 2149, a time when all life on planet Earth is threatened with extinction. In an effort to save the human race, scientists develop a portal allowing travel 85 million years back in time to prehistoric Earth. The Shannon family (father Jim, his wife Elisabeth, and their three children Josh, Maddy and Zoe) join the tenth pilgrimage of settlers to Terra Nova, the first human colony on the other side of the temporal doorway. However, they are unaware that the colony is in the middle of a group of carnivorous din