28 January 1986. The U.S. space shuttle Challenger exploded just after takeoff. All 7 crew members were killed. pic.twitter.com/sObm3cXuOY

— Prof.Frank McDonough (@FXMC1957) January 28, 2018

from http://twitter.com/FXMC1957
on: January 28, 2018 at 04:35AM