The satpass script provides satellite visibility predictions, given the position of the observer and the NORAD element sets for the desired satellites. It can acquire the NORAD element sets directly from any site supported by Astro::SpaceTrack. It can acquire the observer's latitude and longitude from http://geocoder.us/, look up star positions in the SIMBAD catalog, and more.
Astro::Aladin is a an object-oriented interface into the resources provided by the CDS Aladin project. The Aladin Java application is driven in script mode using an anonymous pipe, while high level access to resources is provided by the module which disguises the mechanics of the data access.