Barely 100 people ā all masked and seated or standing far apart ā gathered in front of Kennedy Space Centerās Space Mirror Memorial.
The widow of Challenger commander Dick Scobee quietly observed the anniversary from her home in Chattanooga, Tennessee.
In a recent interview, June Scobee Rodgers said the presence of teacher Christa McAuliffe on the flight added to the crewās lasting legacy.
Scobee Rodgers helped establish the Challenger Center for Space Science Education in the wake of the accident, along with the other Challenger families.
This year's observance focused on the Challenger crew ā McAuliffe, Scobee, Michael Smith, Judith Resnik, Ellison Onizuka, Ronald McNair and Gregory Jarvis.