It is extremely likely it is the hypergolic fuel used for the on-orbit manoeuvring rockets. Hypergolic fuel is really nasty stuff. It is likely the same rocke

It is extremely likely it is the hypergolic fuel used for the on-orbit manoeuvring rockets. Hypergolic fuel is really nasty stuff. It is likely the same rocket fuel (maybe the same rockets) as used by the space shuttle (OMS). http://en.wikipedia.org/wiki/Space_Shuttle_Orbital_Maneuvering_System http://en.wikipedia.org/wiki/Space_Shuttle_Orbital_Maneuveri... See also: * http://en.wikipedia.org/wiki/Space_Shuttle_Discovery#Decommissioning_and_display http://en.wikipedia.org/wiki/Space_Shuttle_Discovery#Decommi... * http://en.wikipedia.org/wiki/Hypergolic_propellant#Disadvantages http://en.wikipedia.org/wiki/Hypergolic_propellant#Disadvant...