NASA's Day of Remembrance: Three tragedies that shook the space program

The crew of Apollo 1 during training in Florida in January 1967. From left, Virgil "Gus" Grissom, Edward H. White II, and Roger B. Chaffee.

NASA holds a Day of Remembrance every year in late January or early February because, though decades apart, the agencies three great tragedies all occurred between Jan. 27 and Feb. 1. 

Originally scheduled for Jan. 31, this year's Day of Remembrance was postponed until Feb. 7 because of the partial government shutdown. 

Gus Grissom, Edward White and Roger Chaffee sit inside a practice module at Cape Kennedy in Florida.

The Apollo 1 mission was supposed to be the first of several crewed flights to prepare for NASA's first moon landing, but the spacecraft never made it off the launch pad. 

An investigator looks at the charred interior of the Apollo I command module after the flash fire that killed the astronauts.

All three men were killed on Jan. 27, 1967, when a fire erupted inside the Apollo command module during a preflight test.

Photos: The Apollo 1 fire

The space shuttle Challenger's mission in 1986 was meant to mark a milestone in spaceflight: the first orbital voyage of an American teacher. NASA's choice for the honor was Christa McAuliffe, a social studies teacher at Concord High School in New Hampshire.

Here, McAuliffe rides past the New Hampshire State House in Concord with her daughter Caroline and son Scott, during a Lions Club parade on July 21, 1985. 

The crew of the space shuttle Challenger, from left: Ellison Onizuka, Mike Smith, Christa McAuliffe, Dick Scobee, Greg Jarvis, Ron McNair and Judy Resnick.

Classmates of the son of America's first teacher-astronaut cheer as Challenger lifts off.

The boy in the white hat and glasses at center is Peter Billingsley, the star of "A Christmas Story" and a spokesman for the young astronaut program.

The space shuttle Challenger exploded 73 seconds into flight.

The shuttle’s fuel tank tore apart, spilling liquid oxygen and hydrogen, which formed a huge fireball at an altitude of 46,000 feet.

Photos: The Challenger disaster

This picture of Columbia's crew was on a roll of unprocessed film recovered from the debris after the space shuttle disintegrated. The crewmembers struck a "flying" pose for their traditional in-flight crew portrait in the Spacehab research module.

From left, bottom row, are Kalpana Chawla, commander Rick Husband, Laurel Clark and Ilan Ramon. In the top row are David Brown, William McCool and Michael Anderson.

Debris from the space shuttle Columbia streaks across the sky over Tyler, Texas, on Feb. 1, 2003.

Columbia broke apart at an altitude of about 200,000 feet over Texas, killing all seven astronauts just minutes before they were slated to land in Florida.

A small brush fire burns after being ignited by debris from the Columbia accident outside Athens, Texas. The shuttle's wreckage was scattered over a five-state area.

NASA's Kennedy Space Center stores about 84,000 pounds of debris from the space shuttle Columbia, representing 40 percent of the spacecraft. The space agency occasionally loans out pieces for engineering research.

Photos: The Columbia shuttle tragedy

Vice President Mike Pence walks with June Scobee-Rodgers, widow of Challenger Commander Dick Scobee to see the Challenger memorial during the NASA Day of Remembrance ceremony at Arlington National Cemetery on Feb. 7, 2019.

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