CAPE CANAVERAL, Fla. — We are in the midst of the most somber week for NASA.

What You Need To Know

  • January 28, 2021, is NASA's annual Day of Remembrance

  • The day is a reflection on the 25 astronauts and test pilots who have died in the pursuit of the U.S. space program

  • The day also marked the 35th anniversary of the Challenger disaster

Three tragic accidents, just days apart over the space program's history.

The annual NASA Day of Remembrance at the Kennedy Space Center Visitor Complex is a moment of reflection.

A service at the Astronaut Memorial Foundation's Space Mirror Memorial, which emblazons the names of 25 astronauts and test pilots killed in the pursuit of space.

"We are humbled, as we recall the sacrifices of these brave men and women, who gave their lives, for the broader cause of exploring an understanding our universe," said Kennedy Space Center Deputy Director Janet Petro.

The Apollo 1 launch pad fire killed three astronauts January 27th, 1967.

"I had some quiet time yesterday," said Sheryl Chaffee, whose father Roger died along with Gus Grissom and Ed White.

She knows exactly what the families are going through, even so many years later.

"I understand, I know what you're feeling," she said. "We do get stronger and we are going to be OK."

The Shuttle Columbia accident claimed the lives of the seven member crew February 1st, 2003.

The orbiter was destroyed over Texas as it was coming home.

And thirty-five years ago, on January 28, 1986, the seven-member Shuttle Challenger crew was killed when the orbiter broke apart 73 seconds after liftoff from the Kennedy Space Center.

"These are things that stay with a person the rest of their life," said former Shuttle Program Launch Director Mike Leinbach, who was a young engineer at KSC when he witnessed the Challenger disaster.

Seventeen years later he was leading the flight of Columbia.

"The families were there, it didn't show up, and it was such an empty feeling," Leinbach tells us. "I don't ever want to see another name up there."

A wreath was placed at the foot of the memorial.

And guests placed flowers in honor of the heroes we have given the ultimate sacrifice for our quest of space.

A somber day as this country presses on to once again return to the moon, and eventually Mars.

"I think they are would want us to continue," said Chaffee. "If we didn't it would be a waste. They gave too much."