On this day: February 26

POSTED: 11:02 AM PST February 25, 2013    UPDATED: 11:00 PM PST February 25, 2013 
Grand Canyon blurb

The Grand Canyon becomes a national park, Michael Jackson's "Thriller" album hits No. 1, a truck bomb explodes under the World Trade Center, and teenager Trayvon Martin is shot and killed, all on this day.