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

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.

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.

Located in the Pacific Ocean, the Challenger Deep is the deepest point on Earth, extending to depths a mile deeper than Mount Everest is tall.

Explore the interior and exterior of the Atlantis and Endeavour space shuttles, including their flight decks, cargo bays, and other compartments.

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

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.

The Challenger disaster grounded the space shuttle fleet for nearly three years, exposed deep flaws in NASA's leadership, and prompted significant changes to the agency's safety oversight and decision-making culture.

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.

Metal wreckage found in a Canadian farm turned out to be SpaceX spacecraft debris

The pieces of the wreck included a 36-kilogram aluminum spear more than 2 meters long, and its origins were confirmed by satellite tracker Jonathan McDowell. No government acknowledged or took accountability for the space trash, which SpaceX later quietly retrieved.

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.

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.

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.

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.

In honor of scientific exploration, all five launched space shuttles were named after ships that traveled the oceans, but a campaign from 'Star Trek' fans led to the shuttle prototype being named Enterprise.

Although it drew inspiration from spaceplane concepts of the 1920s, the Space Shuttle program began to take shape after the Space Race, as the US sought to establish a space station and a reusable transportation system for astronauts and satellites.

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.

View a timeline of NASA's Space Shuttle program, which saw five reusable orbiters take a total of 355 astronauts across a combined distance of almost six trips to the sun.

Major milestones of the Space Shuttle program's 135 missions included the launches of the Hubble Space Telescope and the Chandra X-ray Observatory, and the first American woman and African-American astronauts in space.

Watch the lessons Christa McAuliffe was supposed to teach aboard Challenger

After the Challenger disaster prevented McAuliffe from teaching in orbit, educators-turned-astronauts Joe Acaba and Ricky Arnold filmed her planned science demonstrations aboard the International Space Station during the 2017-18 school year.

Take a 360-degree tour of Discovery with Kathryn Sullivan and Charles Bolden, who flew together on the space shuttle during its deployment of the Hubble Space Telescope. (VR device-compatible)

View a 3D visualization of how space shuttles were built and launched into orbit from NASA's Kennedy Space Center.

Researchers discover a massive Lake Superior shipwreck

A 292-foot Whaleback ship, Barge 129, was found in Lake Superior 120 years after a storm sank it, the Great Lakes Shipwreck Historical Society said.

A SpaceX spacecraft's battery debris survived reentry and crashed into a Florida home

Although NASA expected the debris to disintegrate after it was jettisoned from the International Space Station in 2024, the flight support component survived reentry. No injuries were reported from the incident.

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 Columbia disaster contributed to the end of the Space Shuttle program and NASA's reliance on commercial partners such as SpaceX and Boeing to transport astronauts and cargo.

Explore a series of NASA visualizations tracking satellites and space debris

The series illustrates the population of objects orbiting Earth as of February 2024, using data from US Space Command. These include active satellites, defunct spacecraft, rocket bodies and debris fragments larger than roughly 10 centimeters in low Earth orbit.

Explore a database of more than 220,000 shipwrecks, the largest compilation to date.

In 2021 US dollars, space shuttles cost $65,400 per kilogram, making them the most expensive spacecraft for payloads greater than 20,000 kilograms.

During the Space Shuttle program, NASA's Shuttle Carrier Aircraft—two specially modified Boeing 747s—transported space shuttles between landing sites and launch facilities.

Historians estimate that only 1% of shipwrecks have been discovered.

Scientists discover what looks like an underwater road

Crew aboard the Exploration Vessel Nautilus discvered a “yellow brick road” that looks it leads to Atlantis. Climage change may affect future ocean studies.

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.

There are trillions of pieces of space trash that are too small to be tracked

Although scientists monitor more than 24,000 pieces of large orbital debris, space junk can be as small as a paint fleck. The density of this trash is steadily increasing with the growth of the space industry on Earth.

Commercializing space debris removal may follow the commercialization of launches

Active debris removal is likely to focus on larger derelict objects, which are more easily identified and yield better financial returns. One actively researched possibility involves using netting to capture derelict objects before towing them into a controlled descent into an ocean.

As of 2025, over 131 million pieces of debris orbit Earth

These pieces range in size from a grain of sand to the size of a bus and orbit with an average speed of 10 kilometers per second.

You are 65,000 times more likely to be struck by lightning than to be hit by space trash

In 2023, about 1,500 pieces of space junk fell to Earth, with most consisting of payload fragmentation debris. The vast majority that falls back to Earth burns up before reaching the surface, making it three times less likely to be struck by space trash than by a meteorite.

Watch footage from the moments the Titanic wreck was discovered by a joint US-French research team in 1985.

Space trash forced astronauts on the International Space Station to take shelter

An inactive Russian satellite broke up into nearly 200 pieces, prompting astronauts on the space station to take shelter in a docked spacecraft and a capsule that could be used to escape in case of emergency.

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.

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.

In 2023, there were nearly as many payloads in LOE as trackable pieces of debris

In 2021, the European Space Agency estimated that more than 130 million space debris objects larger than 1 millimeter were in low Earth orbit, though only about 22,000 were being tracked. As of late 2025, the tracked total exceeds 49,000.

The history of deep-sea mining and its governance by the International Seabed Authority

The British HMS Challenger research vessel identified metal-rich seafloor rocks between Hawaii and Mexico in the 1870s, but rules governing which nations control which parts of the ocean were not established until 1958 by the UN. It later established the ISA to oversee mineral-related operations in international waters.

Apollo astronauts left items in the moon's 'toss zone,' including golf balls, family photos, and bags of human waste, to make room for lunar rocks.

Visualizing Earth's space garbage

An unsavory byproduct of humanity's brilliant exploration of space, the Moon, and more, is the rapid production of space debris floating around in orbit. Its estimated over 25,000 objects are in orbit, a number that grows everyday as satellites are decommissioned, rockets enter orbit, and more. Now, you can visualize what this debris looks like from a zoomed-out perspective with this brief video.

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.

The unloading and maneuvering of the space shuttle's payload were accomplished by the Shuttle Remote Manipulator System—a robotic arm designed and constructed in Canada, which led to it being colloquially known as the Canadarm.

View a schematic of the space shuttle orbiter, including the layout of the flight deck and mid-deck for astronauts, the cargo bay for payloads, and various support systems, such as avionics equipment and the fuel system.

Although an estimated 99.999% of the deep ocean has not been explored, techniques such as sonar have been used to identify the deepest known point in each of Earth's five oceans.

Spacecraft remnants and human waste left behind on the moon add to the trash in space

As more countries reach the moon with successful probe landings and unsuccessful crashes, more materials are left behind, adding to the amount of trash that needs to be retrieved. A United Nations treaty declared the moon a common heritage of humanity, exempting any one country from exclusive responsibility for cleanup.

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.