Originally from ticket #19433.
Is it possible to add star catalogs, such as the entire GSC-II, which contains data on almost a billion stars?
It is possible to add your own database, but the developers have said that at this time it is not computational possible to add the GSC-II, which contains data on almost a billion stars?
You can build an add a database that is of tens of thousands. But, not a billion. So, the answer is no. And you're, in fact, advised not to try to do so.
However, the developers did say in the future it is possible they will be able to add the catalog to SN7 - it would be computed differently than if you did it yourself.
Hopes this helps. Sorry to disappoint.
Starry Night & Sky Safari Software Support Team