Question: What's the longitude named Zipaltonal Fluctus in 1997 with a diameter smaller than 490?
SQL: SELECT "Longitude" FROM "2-16799784-12" WHERE "Year named" = 1997.0 AND "Diameter (km)" < 490.0 AND "Name" = 'Zipaltonal Fluctus';

Question: What's the diameter of Kaiwan Fluctus?
SQL: SELECT "Diameter (km)" FROM "2-16799784-12" WHERE "Name" = 'Kaiwan Fluctus';