user: Question: What date sent has Cancer as the constellation?
Columns: ['Designation HD', 'Constellation', 'Date sent', 'Arrival date', 'Message']
Types: ['text', 'text', 'text', 'text', 'text']
Sample row: ['HD 186408', 'Cygnus', 'May 24, 1999', 'November 2069', 'Cosmic Call 1']
SQL:

assistant: SELECT "Date sent" FROM "Table" WHERE "Constellation" = 'Cancer';