CAPE CANAVERAL, Fla. – A fire swept through the cabin of Apollo 1 50 years ago Friday, killing NASA astronauts Gus Grissom, Ed White and Roger Chaffee. In a "Day of Remembrance" Thursday, the agency honored their sacrifice to space exploration.
The last week of January into February is a dark period in space exploration history marred by the Apollo 1 fire and the Columbia, on Feb. 1, 2003, and Challenger, Jan. 28, 1986, space shuttle explosions in the same week decades later.
In a ceremony Thursday at NASA's Kennedy Space Center attended by family, former astronauts and NASA leaders the three men were honored.
Among the many astronauts attending were the two surviving crew members of Apollo 11, Buzz Aldrin and Michael Collins, as well as Apollo 16 moonwalker Charlie Duke.
Collins, who piloted the first manned moon landing, remembered working with the men and credited them with the eventual moon landing because of their sacrifice.
For Chaffee, the moon was more than just a destination, Collins said.
"It was a fascinating planet for him," Collins said.
Chaffee would have been just as interested in studying the moon's geology as walking on it, he said.
Grissom was dedicated to his craft and the mission.
"If you were looking for Gus, try the night shift in the factory," Collins said. "He would be there."
White was a natural pilot taking "to the Air Force kind of like a duck to water," Collins said.
NASA would not have completed the end-of-decade deadline set by President John F. Kennedy to land a man on the moon, if it were not for the Apollo 1 crew, Collins said.
Chaffee's daughter, Sheryl Chaffee, spoke off her "8-year-old world being torn apart" the day her father died and having a reccurring dream that he would talk through her front door.
Sheryl Chaffee followed in her father's footsteps working at NASA for 33 years before recently retiring. She met people who were there the day he died and she had deep empathy for the family's of the Challenger and Columbia crews.
As the years and decades rolled by, Apollo 1 became a mere footnote in space history. Chaffee recalled having to buy a memorial wreath herself to display at the space center on the 20th anniversary.
"It became my mission to make sure we never forget," she said.
Kennedy Space Center director and former astronaut Bob Cabana said he was too far removed from Apollo 1 to feel directly impacted, but in 2003 he was tasked with telling the family of the Columbia crew that their loved ones weren't coming home.
Cabana said NASA has learned from its past and the agency went to long without a memorial for "Gus, Ed and Roger."
He challenged the agency to learn from the tragedies by fostering an environment "where everyone feels free to voice their concerns and all data is brought forward to make an informed decision."
Cabana closed out with the unfortunate slogan of space exploration, "Ad Astra Per Aspera" -- through hardship to the stars.
On Friday, NASA is opening an Apollo 1 exhibit, featuring the hatch that prevented the three astronauts from escaping. It has been concealed for the past half-century along with the capsule.
The Associated Press contributed to this report.