extra astronomical / calendar / epoch features that mathematica does not have.
has many new functions.
supports multiple calendars (julian, gregorian, synodic, anomalistic). supports JDN conveniently, shows moon phase est. NEW: supports day number from 0 of any calendar
conversion all-way between supported calendars
supports multiple epochs and epoch generation. convert between some epochs without calendar support, ie, J2000.0, JDN, to some effect can create/import epochs and use...