NASA pictures come from:
Finley-Holiday Film Corp.
CA 90608, USA.
Phone (in USA) 800 345-6707
Fax 310 693-4756
Astronomical pictures come from:
Astronomical Society of the Pacific
390 Ashton Avenue
San Francisco, CA 94112, USA.
Phone (in US) 415 337-2624.
Slide sets of space and astronomy are available from many planetariums
in the US, or in the UK from
Northern Ireland BT61 9DB, UK.
Phone (in UK) 01861 524725
(from abroad) (+44) 1861 524725
Alternatively, try contacting a supplier of astronomical telescopes, who may have slide sets or posters. For a list of UK suppliers, follow the links provided by the Society for Popular Astronomy.
A series of slides of constellations and other astronomical objects is available in the UK from the Federation of Astronomical Societies.