CAPE CANAVERAL, Fla. -- Twenty-five years ago, seven astronauts died aboard space shuttle Challenger when it exploded shortly after liftoff.
NASA officials, families and former astronauts gathered Friday morning at an outdoor memorial at Florida's Kennedy Space Center to mark the somber anniversary.
The accident on Jan. 28, 1986 -- just 73 seconds into flight -- killed the Challenger crew, including schoolteacher Christa McAuliffe.
The anniversary comes as NASA is winding down the space shuttle program. The fleet will be retired after three more flights this year to the International Space Station.
Speakers at Friday's ceremony included the widow of Challenger's commander, June Scobee Rodgers, who was instrumental in establishing the Challenger Center for Space Science Education. The 48th learning center opens Friday in Louisville, Ky.
"The entire world knew how the Challenger crew died," she said. "We wanted the world to know how they lived and for what they were risking their lives."
The other members of the Challenger crew were Dick Scobee, Michael Smith, Ellison Onizuka, Judith Resnik, Ronald McNair and Gregory Jarvis.
The ceremony was held at the Space Mirror Memorial, a granite monument bearing the names of all 24 astronauts who have died in the line of duty.