Submit sites here if the primary product is a certificate attesting to something. Star naming services should go to the Star Names subcategory. Deeds to extraterrestrial property and other similar services go here. Tangible memorabilia (astronomy or space themed patches, coffee mugs, whatever) should be submitted to Shopping:Recreation:Science and Nature:Astronomy:Space Memorabilia.
Space novelties are astronomy or space related intangibles. The delivered product is typically a certificate of some sort.