Space & Innovation

NASA Remembers Fallen Astronauts, Pledges Mars Mission

The US space agency marked the 30th anniversary Thursday of the explosion of the space shuttle Challenger with a pledge to remember lost astronauts as it presses on toward Mars.

The US space agency marked the 30th anniversary Thursday of the explosion of the space shuttle Challenger with a pledge to remember lost astronauts as it presses on toward Mars.

At the Kennedy Space Center in Florida, where the shuttle blasted off on January 28, 1986, singers outfitted in red and blue belted out the Star Spangled Banner for a crowd that included relatives and friends of the seven killed that day.

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"The Challenger crew will forever be young, and will never be forgotten," said Bob Cabana, a former astronaut and director of the Kennedy Space Center.

"They continue to motivate us to explore."

A wreath-laying ceremony was planned for Arlington National Cemetery in Virginia as NASA commemorated the 24 US lives lost in space disasters and test flights over the years.

"As we undertake a journey to Mars, they will be with us. They have our eternal respect, love and gratitude," said a statement by NASA administrator Charles Bolden, a former astronaut.

"On this solemn occasion, we pause in our normal routines and remember."

Six NASA astronauts and Christa McAuliffe -- who would have been the first teacher in space -- were killed in the Challenger disaster, when the shuttle exploded 73 seconds after liftoff.

ANALYSIS: Memories of Challenger Accident Still Shaping NASA

The cause was a failed booster engine, NASA said.

The other major shuttle accident was on February 1, 2003. Seven people died aboard the Columbia shuttle when it broke into pieces while re-entering Earth's atmosphere.

NASA said later that a piece of foam had come loose from the external tank during launch, and formed a hole in one of the shuttle's wings, causing it to break up 16 minutes before it was to have landed.

The US space agency also commemorated the three men who died in the Apollo 1 launch pad fire in 1967, before the nation ever made it to the moon.

"Remembering the crews today that we've lost, especially my best friend Ed White who perished in the Apollo 1 fire," astronaut Buzz Aldrin -- the second person to step foot on the Moon after American astronaut Neil Armstrong -- said on Twitter.

Bolden also recalled the 1967 loss of Mike Adams who died on an X-15 hypersonic rocket-powered aircraft, and others who perished in "test flights and aeronautics research throughout our history."

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Shortly after taking office, US President Barack Obama cancelled a NASA program to return to the moon, saying he preferred to funnel resources into deep space exploration and aimed to have a human mission to Mars under way by the 2030s.

The space shuttle program was formally ended in 2011 after three decades of ferrying astronauts to and from low-Earth orbit.

Its retirement left the United States with no vehicle for human space travel.

In the meantime, the world's astronauts hitch rides to the International Space Station aboard Russia's Soyuz capsules, while private companies Boeing and SpaceX ready their own spaceships for use in 2017 and beyond and NASA focuses on building its Orion deep space capsule.

The space station crew remembers NASA's fallen astronauts on Jan. 28. NASA astronaut and ISS commander Scott Kelly (right) led the televised remembrance celebration from orbit, remembering NASA's fallen astronauts on the Apollo 1, Challenger and Columbia missions, highlighting "how their spirit and their legacy lives on in our achievement in space." NASA astronaut Tim Kopra (left) and British astronaut Tim Peake (center) joined Kelly.

By January 1986, NASA had four space shuttles regularly flying to put communications satellites, science experiments and military spacecraft into orbit, and to conduct research in microgravity during missions that lasted about a week. The U.S. space agency had treated two sitting congressmen and a Saudi prince to rides on the shuttle, which could accommodate crews as large as eight. For the program’s 25th flight, which blasted off on Jan. 28, 1986, high school social studies teacher Sharon Christa McAuliffe joined five NASA astronauts and payload specialist Gregory Bruce Jarvis, with Hughes Space and Communications, aboard space shuttle Challenger on a mission to dispatch two satellites, study Comet Halley and host live science lessons for students from orbit. Pictured above from the left are McAuliffe, Jarvis, flight engineer Judith Resnik, commander Francis Richard Scobee, mission specialist Ronald McNair, pilot Michael Smith and mission specialist Ellison Onizuka during a countdown training session in Florida on Jan. 9, 1986.

ANALYSIS: Memories of Challenger Accident Still Shaping NASA

New Hampshire school teacher Christa McAuliffe, center, and her backup Idaho’s Barbara Morgan, right, were selected from among more than 11,000 applicants to train for a space flight as part of a NASA educational outreach program called Teacher in Space. NASA hoped to build popularity for the shuttle program by demonstrating how an ordinary person could fly in space.

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On the morning of Jan. 28, 1986, temperatures were a few degrees below freezing at the Kennedy Space Center, which raised some concerns about how the shuttle’s solid rocket boosters would perform. The two boosters, which attach to the shuttle’s orange external fuel tank, fire during the first two minutes of flight and then are jettisoned. The shuttle’s three liquid-fuel main engines continue burning for another 6.5 minutes to carry the spaceship into orbit. Engineers’ safety concerns were never raised to NASA launch managers, which cleared Challenger for liftoff at 11:38 a.m. EST. Pictured here are icicles on the launch complex.

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The flight did not last long. A series of events rapidly unfolded beginning with a big puff of gray smoke spurting from a joint on the shuttle’s right solid booster rocket less than a second after blastoff. Eight blacker puffs of smoke followed over the next 2.5 seconds. Thirty-seven seconds into the flight, Challenger encountered a series of high-altitude wind shears, which the boosters’ steering system automatically compensated for. After passing through the region of maximum aerodynamic pressure, the shuttle’s main engines were throttling up and the boosters were increasing their thrust when a flicker of flame appeared on the right solid rocket booster in the area known as the aft field joint. By a minute into the flight, the flame was a plume and the right booster was losing chamber pressure, indicating a growing leak. By 64.6 seconds after liftoff, the flames had breached the shuttle’s fuel tank, creating an abrupt change in the shape and color of the plume. With leaking hydrogen now feeding the flame, the end was near. At about 72.2 seconds the lower strut holding the right booster to the tank broke away, leaving it free to rotate around the upper attachment strut. A second later, the tank began to break apart, releasing massive amounts of liquid hydrogen. About the same time, the rotating booster rocket hit the tank, releasing more hydrogen as well as liquid oxygen. Challenger, traveling at just under twice the speed of sound at an altitude of 46,000 feet, was quickly engulfed. The orbiter broke apart, its main engines still firing, 73 seconds after launch.

Wreckage recovered from the Atlantic Ocean shows where part of the shuttle’s booster rocket was burned away.

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NASA quickly determined that a rubber O-ring, pictured here, on the shuttle’s right booster rocket failed, allowing hot gases to seep out. A presidential commission appointed to investigate the accident determined that cold weather was a contributing factor.

After the investigation into the accident was finished, the recovered debris was put into two abandoned Minuteman Missile silos at Cape Canaveral Air Force Station, just south of the Kennedy Space Center.

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It would be more than 2.5 years before NASA was ready to fly the shuttle again. Besides redesigning the booster rocket joints, the agency made hundreds of changes to the shuttles’ engines, brakes and other hardware, upgraded software and re-organized management and operations to improve safety. NASA appointed its first all-veteran crew since Apollo 11 for the return-to-flight mission. Pictured here, in NASA’s post-Challenger mandatory pressurized flight suits, are the STS-26 astronauts: commander Frederick Hauck, lower right, pilot Richard Covey, lower left and upper row from left, mission specialists John Michael Lounge, David Hilmers and George "Pinky" Nelson.

A humbled and determined NASA prepared space shuttle Discovery for launch on what was considered a post-Challenger test flight. The primary payload was a replacement NASA communications satellite for the one lost on Challenger. During the mission, which launched on Sept. 29, 1988, the Discovery crew paid tribute to Challenger astronauts. “We have resumed the journey. Dear friends, your loss has meant that we could confidently begin anew,” the crew radioed during the flight. Discovery's recovered booster rockets showed no signs of leakage or overheating.

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NASA never forgot about its Teacher-in-Space program, though the shuttle was now off-limits to all but professional astronauts. The agency allowed Mercury Seven astronaut and former senator John Glenn to fly a one-time senior health research mission and decided to create a new category of astronaut for educators, which would allow Christa McAuliffe’s backup Barbara Morgan to finally fly. Morgan joined the astronaut corps in 1998 and began training to become a mission specialist. The shuttle program suffered its second fatal accident on Feb. 1, 2003, and flights were suspended for another 2.5 years. Spurred by the loss of Columbia, the United States decided to end the shuttle program after NASA finished building the space station. Morgan flew on the fifth mission after the Columbia disaster, blasting off aboard shuttle Endeavour on Aug. 8, 2007.

One of the first lessons learned from the Challenger accident is that astronauts need an emergency escape system in case of a failed launch, the most dangerous part of a space mission. NASA is returning to a capsule design for its next human spaceship, called Orion, which will be mounted on top of its Space Launch System rocket. In case of an emergency on the launch pad or during the ride to orbit, Orion will have its own rocket system that can carry the spaceship away from a failing booster. Artist image of Orion on top of a Space Launch System rocket.

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NASA and other government agencies no longer have a monopoly on flying people in space. A privately built suborbital spaceship called SpaceShipOne made three flights out of the atmosphere in 2004 and laid the groundwork for a fleet of passenger spaceships under development by Virgin Galactic. Meanwhile, SpaceX and Boeing are preparing commercial space taxis that NASA has hired to fly crews to and from the International Space Station. Like NASA’s Orion capsule, which is designed for deep-space destinations beyond the station, Boeing’s CST-100 Starliner and SpaceX’s Dragon, pictured here, will be able to fly themselves to safety in case of an emergency. SpaceX tested its launch pad abort system in May 2015.

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