On this day: May 20

POSTED: 03:26 PM MDT May 17, 2013    UPDATED: 12:00 AM MDT May 20, 2014 
Vasco da Gama arriving in India, 1498

Vasco da Gama arrives in India, Christopher Columbus dies, Norman Rockwell makes his Saturday Evening Post cover debut, HIV is discovered, and "Cheers" airs its series finale, all on this day.