There we go..
In everybody Hates Hugo we learn that the hatch has a supply of Apollo chocolate bars. Apollo the Greek god is related to six constellations:
Cygnus: swan
Sagitta: arrow
Corvus: crow
Crater: goblet
Ophiuchus: serpent handler
Orion: hunter
As you can see two of these are the symbols on Dharma logos we have seen so far..
Orientation tape says 3/6
Ive heard there is a leaked new Dharma video, its genuinity is unknown but seems to look pretty good It has totally irrelevant logos but shows 6 stations.
Official Dharma web site (mock one, owned by ABC) shows 7 stations, but we can assume one of them can be like a hub, or control center..