Watch the lessons Christa McAuliffe was supposed to teach aboard Challenger

Aboard Challenger, Christa McAuliffe would have been the first teacher in space

The social studies teacher from Concord, New Hampshire, was selected from over 11,000 applicants to NASA's Teacher in Space program. Had the disaster not ended the mission, McAuliffe planned to teach lessons and conduct microgravity experiments in space.

The Teacher in Space program was launched in 1984 to highlight spaceflight in US classrooms

Announced by President Ronald Reagan, the program drew more than 11,000 teacher applicants nationwide. Christa McAuliffe was selected to fly on STS-51L, with plans to teach live lessons from orbit before the Challenger disaster ended the mission.

Watch the Challenger disaster, which killed all seven astronauts aboard, unfold live.

About 2.5 million American students watched the Challenger disaster live

Because of the publicity of the Teacher in Space program, millions of students viewed Challenger's liftoff in school classrooms—turning the explosion into a shared national traumatic experience marked by shock, silence, and grief.

The Challenger disaster ended NASA's plan to fly ordinary Americans in space

The explosion of the Challenger halted NASA's civilian spaceflight ambitions for decades, including plans to send teachers, journalists, artists, and other nonastronauts into orbit—an effort aimed at building public support that quietly disappeared after the 1986 disaster.

Explore what Challenger was supposed to do on its mission

STS-51L's planned seven-day mission included deploying satellites, studying Comet Halley, conducting fluid dynamics experiments, and broadcasting live lessons from orbit—routine scientific and educational tasks that were never carried out after the shuttle was lost shortly after launch.

'May your future be limited only by your dreams.'

- Teacher and astronaut Christa McAuliffe (1948-1986)

Watch the Challenger disaster unfold in real time

On January 28, 1986, Space Shuttle Challenger broke apart just 73 seconds after liftoff. This live CNN broadcast captures the tragedy as it happened—second by second—showing the shock and confusion of one of NASA's darkest moments.

Big Bird was almost included on the Challenger mission

As part of NASA's early outreach ideas tied to the Teacher in Space program, Sesame Street's Big Bird was briefly considered for a Challenger flight, but the plan was dropped because the oversized costume could not fit safely inside the shuttle.

Beyond technical failures, the Challenger disaster exposed deep flaws in NASA's leadership.

Listen to the five-part podcast series that reconstructs how Challenger failed

The "American Scandal" podcast devotes a five-part series to Challenger, tracing the engineering warnings, internal pressure to launch, the moment of the explosion, and the long aftermath that reshaped NASA's safety culture.

Space tourism opportunities have been explored since the end of the Apollo era

In the 1970s, Rockwell International, a NASA contractor, and others investigated manufacturing passenger modules that could fit into the Space Shuttle's payload bay. NASA also opened spaceflights to nongovernment professionals, but many such programs were ended after the Challenger disaster, which killed the first Teacher in Space participant.

The Challenger disaster delayed the launch of the Hubble Space Telescope

The 1986 explosion of the space shuttle shortly after liftoff killed seven crew members and grounded NASA's space fleet. Scientists used the downtime to refine ground control software and upgrade telescope instrument sensitivity, but maintaining the telescope's clean room storage cost NASA approximately $6M per month.

The commander of the Challenger mission began his career as a mechanic in the Air Force

Lt. Col. Dick Scobee began his career as an Air Force aircraft mechanic, later becoming a Vietnam combat pilot, test pilot at Edwards Air Force Base, and ultimately the commander of Challenger's STS-51L mission.

Judith Resnik was the second American woman to fly in space

A PhD in electrical engineering, Judith "Judy" Resnik flew aboard Space Shuttle Discovery in 1984, becoming the second American woman in space, and later served as a mission specialist on Challenger's STS-51L mission.

President Reagan postponed the State of the Union after Challenger

In his Oval Office address delivered the night of the disaster, President Ronald Reagan spoke directly to the nation about the loss of Challenger and its crew, postponing that evening's scheduled State of the Union to address the tragedy.

Evidence suggests some of the Challenger's crew may have been alive after the explosion

Recovery of the intact crew cabin and later analysis of flight data led investigators to conclude the astronauts likely survived the initial breakup and remained alive during the roughly two-minute descent before the cabin struck the ocean.

Ellison Onizuka was the first Asian American in space

A member of the 1986 Challenger mission crew, Onizuka was also the first Hawaiian in space, having been one of 35 people selected from a pool of 8,000 applicants for astronaut training in 1978.

Explore a timeline of the International Space Station National Lab

In 1984, President Ronald Reagan called for establishing a human presence in space, which began with NASA astronaut Bill Shepherd and Russian cosmonauts Yuri Gidzenko and Sergei Krikalev on November 2, 2000. Humans have continuously occupied the ISS every day since.

Mission specialist Ronald McNair was the second African American to fly in space

Growing up in Lake City, South Carolina, McNair described deep self-motivation as key to overcoming struggles in mathematics, having come from a family with no one having a background in mathematics or science. He credited his own curiosity and discipline developed through athletics—especially karate—with helping him build resilience.

Challenger pilot Michael Smith was a Navy test pilot and Vietnam veteran

Michael J. Smith, a US Naval Academy graduate and combat pilot in Vietnam, flew nearly 4,900 hours across 28 aircraft types before becoming a Navy test pilot and NASA astronaut, serving as the pilot of Challenger's STS-51L mission.

In 2022, a piece of Challenger was discovered on the ocean floor

While searching for World War II wreckage near Cape Canaveral, Florida, for a documentary, divers discovered debris on the seafloor that NASA later confirmed to be a piece of Space Shuttle Challenger wreckage. The piece is at least 15-by-15 feet in size and partially buried under sand.

Gregory Jarvis was an Air Force veteran who flew as a civilian payload specialist on Challenger

A Hughes Aircraft engineer with a background in electrical engineering, payload specialist Gregory Jarvis was assigned to STS-51L to study how fluids and satellite propellants behave in weightlessness during shuttle maneuvers.

The night before the disaster, not everyone signed the Challenger's launch authorization form

Allan McDonald, director of the booster rocket program at NASA contractor Morton Thiokol, refused to sign, believing ice on the spacecraft could damage the orbiter's heat tiles and that cold temperatures could cause O-ring failure. He later testified that management had overruled objections from engineers.

Mae Jemison, the first Black woman in space

Astronaut Mae Jemison describes her journey from space-loving girl in Chicago to astronaut looking down on Chicago and thinking about her younger self in this two-minute video. Physician, engineer, educator, entrepreneur and the first woman of color in the world to go into space, Dr. Jemison was a NASA astronaut for six years.

The Columbia disaster exposed fatal flaws in NASA's shuttle program

On Feb. 1, 2003, Space Shuttle Columbia broke apart during reentry, killing all seven astronauts aboard. The tragedy revealed long-ignored safety warnings, leading NASA to ground the shuttle fleet and overhaul its safety culture.

Take a virtual tour of the Space Shuttle

This interactive 3D experience allows users to navigate the Space Shuttle virtually, moving through the cockpit, crew cabin, airlock, and payload bay to view the vehicle's layout and systems from the inside.

Watch a livestream of Earth from the International Space Station

The feed is made possible by the SpaceTV-1 camera system, which is live over 20 hours a day. Video replays are shown during routine loss of signal communications with the inter-satellite link relaying the video data.

Faulty wiring and flammable materials caused a fire in the Apollo 1 command module

During a launch rehearsal test on Jan. 27, 1967, the fire took the lives of astronauts Gus Grissom, Ed White, and Roger Chaffee. The tragedy led to improvements to CM construction and the development of a single-piece hatch for escapes.

Watch a firsthand account of Hubble's first service mission to repair its faulty mirror

Hubble senior project scientist David Leckrone recalls initial public ridicule over the microscopic manufacturing error that put NASA's reputation at stake. In this behind-the-scenes interview, he breaks down the innovative fix deployed by space shuttle astronauts during Hubble's first servicing mission.

View 60 years of NASA space exploration

Established in 1958—a year after the Soviet Union launched Sputnik 1—the National Aeronautics and Space Administration has taken humanity into outer space and helped reveal the nature of the universe. Historic moments include the Apollo 11 mission putting humanity on the Moon and construction of the International Space Station.

John Glenn's Friendship 7 flight finally put the US in orbit in February 1962

After the Soviets took the lead in the space race, John Glenn's three-orbit Friendship 7 mission on February 20, 1962, made him the first American to orbit Earth. This NASA anniversary piece delivers a minute-by-minute account—from launch delays to splashdown and recovery.

The Challenger disaster led NASA to create an independent safety office

In response to the Challenger accident, NASA established the Office of Safety, Reliability, and Quality Assurance—now known as the Office of Safety and Mission Assurance—to strengthen oversight, elevate safety concerns, and mitigate managerial pressure on technical decisions.

Watch how the Space Shuttle launched

This 3D visualization illustrates the Space Shuttle launch, breaking down the roles of the solid rocket boosters, main engines, the crawler transporter, and the timing sequence that carried the vehicle from liftoff to orbit.

Engineers warned Challenger could fail, but were overruled

Engineer Bob Ebeling and four of his colleagues presented data to NASA officials and managers at NASA contractor Morton Thiokol the night before the launch about how cold temperatures could cause O-ring failure. Ebeling claims to have told his wife then that, "[Challenger is] going to blow up."

Low temperatures led to the equipment failure that caused the Challenger disaster

The polymer chains that make up an O-ring give it the ability to quickly deform and fill in gaps to seal fluids, including the hot gases from the Challenger's rocket boosters. Cold weather on the day of launch stiffened the O-rings, reducing their flexibility and sealing properties.

Hear about the rivalries and unlikely figures that defined the space race

American History Tellers explores the space race across four episodes, tracing stories from Wernher von Braun's push to turn missiles into rockets to the intrigue surrounding Apollo 11 and the moon landing that symbolized the race's end.

Today’s kids would rather be YouTubers than astronauts

While the other children in your kindergarten class might have wanted to be firefighters or astronauts when they grew up, modern kids are different. Lego conducted a study that found children were more likely to say they wanted to be a YouTuber when they grew up than an astronaut.

The Polaris Dawn program led to the first commercial spacewalk

As part of the Polaris program, this first mission included a crew comprising astronauts and SpaceX engineers, who conducted scientific experiments and cultural outreach, such as raising funds for St. Jude Children's Research Hospital.

Explore a deepfake speech of an alternate reality where Apollo 11 failed

As the Apollo 11 astronauts prepared for their journey to the moon, two speeches were drafted for President Richard Nixon: one to be delivered upon the astronauts' success and another to comfort the public in case of failure. This interactive explores the creation of a believable version of the latter.

The wife and mother of two of the Titan submersible victims shares her life since the tragic accident

The loss of the Titan submersible amid its June 2023 dive to explore the wreckage of the Titanic captured headlines worldwide. Christine Dawood had given up her seat on the trip of a lifetime to her 19-year-old son, Suleman, so he could experience the dive with his father. She has since written a book about her experience of the tragedy and about life in its aftermath.

On April 12, 1961, Soviet cosmonaut Yuri Gagarin became the first human in space

In 1961, Soviet cosmonaut Yuri Gagarin became the first human to orbit Earth, deepening US fears of falling behind in the space race. Watch archival footage to see why the mission was such a historic turning point.

Richard Feynman exposed NASA's safety failures on the Rogers Commission

The Nobel Laureate served on the Rogers Commission investigating Challenger, famously demonstrating O-ring failure with ice water and eventually criticizing NASA's culture of risk normalization and management pressure in the final report.

How the Discovery Channel was originally built for lifetime learners

Founder John Hendricks envisioned Discovery as a launchpad for educational content that was both informative and engaging. Since, the channel has spawned dozens of other channels, merged with major studios, and launched its own streaming platforms.

Watch one of the greatest live TV shots ever

While James Burke was filming the 1978 docuseries "Connections" at the site of a rocket launch, he pulled off a perfectly-timed gesture without use of a green screen. Some say its the greatest live shot ever in TV history.

Bill Nye served as a lab assistant in the 'Back to the Future' animated series

Set in an alternate timeline after the conclusion of "Back to the Future Part III," the series starred Jules and Verne—the children of Dr. Emmett Brown and Clara. Each of its 26 episodes concluded with a live-action segment in which Bill Nye performed an experiment related to that episode.

James Webb championed both space science and human spaceflight at NASA

As NASA Administrator during the 1960s, Webb prioritized a balanced approach between manned missions and scientific research, fostering advancements in astronomy, robotic exploration, and university involvement. Despite having no background in science or engineering, Webb oversaw more than 75 space science mission.

The 'maiden of maiden voyages' who taught the world how to fly

In 1939, Clara Adams set the world record for the fastest person to circle the globe via commercial airliner, though she was a passenger and not a pilot. This article explores the impact of Adams' journey on the commercial flight industry. During...

An oxygen tank explosion forced Apollo 13 to abort its moon landing

The 1970 mission—intended to be the third lunar landing—forced astronauts Jim Lovell, Jack Swigert, and Fred Haise to focus solely on their survival. They engineered a makeshift filter to handle the carbon dioxide they produced, which exceeded the lunar module's capacity.

Learn how the Soviets won the early space race

This video traces how Cold War arms competition transformed rocketry into a symbol of global power, following pioneers like Tsiolkovsky and von Braun through World War II and into the 1950s, culminating in the Soviet Union’s launch of Sputnik I in 1957.