Sonja, the tessaract I wrote about the "new headquarter" of our heres, is a mathematical concept.
Called also hypercube, the tessaract is a four dimensional figure made up by six cubes (I am not sure about the number-my school days are long gone). Basically, it's a way of giving our heroes a place to meet, and to store trophy, a training room and a computer to hack into government networks (all things useful to hiding heroes) all inside a circus caravan.
Plus, it's a hommage to the pockets of Prometheus coat. But that is another story....
