Look to this extract from a pdf Clementine document:
"The South-Polar Aitken was revealed by Clementine to be largest known(i.e until that time) impact crater in the solar system,with a diameter of about 2600 km and a maximum depth of almost 12 km..."
Is it clear now?
I don??t know if the SPA is missing in the lunar map of Celestia or only in moon-locs.ssc.
Look at this image:
http://www.earthsky.com/shows/profiles/ ... on_ice.jpg
Or here:
http://us.f1f.yahoofs.com/bc/f4386be8_m ... BBmSA3TxOg
Or here,for a much better resolution:
http://www.designhazard.com/xtar/02_Sol ... thpole.jpg[/url]