When space travel goes wrong

Gus Grissom's Mercury capsule sank in an ocean landing in July 1961, after an explosion blew the escape hatch off prematurely. He swam from the capsule safely.

Three U.S. astronauts, including Gus Grissom, were killed by a fire in January 1967 during a launch rehearsal for the Apollo 1 mission.

Soviet cosmonaut Vladimir Komarov was killed in April 1967 while returning from a successful Soyuz 1 orbit of Earth when the main parachute fails to open.

The U.S. lunar mission Apollo 13 in April 1970 lost the use of an oxygen tank necessary to supply air and power. The three-man crew successfully used the lunar module shown as a lifeboat.

Three Soviet cosmonauts were found dead in their Soyuz 11 spacecraft after an apparently normal landing in June 1971.

Seven crew members aboard the Space Shuttle Challenger were killed in January 1986 when the spacecraft exploded shortly after takeoff.

This photo taken from Chinese television in January 1995 shows a Chinese Long March rocket exploding above its launchpad, killing six people and injuring 23 others.

During a June 1997 docking exercise, an unmanned cargo vessel crashed into Mir, disrupting the station's power supply and partially depressurizing the living quarters.

Investigators inspect debris from the space shuttle Columbia, which broke up over East Texas in February 2003. Seven astronauts were killed.

Water pooled inside the suit and helmet of Italian astronaut Luca Parmitano during a spacewalk outside the International Space Station in July 2013. He made it back to the airlock unharmed.

(CNN) -- Note: This list includes accidents that affected astronauts or other staff related to the spacecrafts. Accidents that involved unmanned spacecraft are not included.

October 24, 1960 - The first space-related fatality happens when a rocket explodes at the Soviet Union's Baikonur Space Center in Kazakhstan, killing 165 people, including Air Marshal Mitrofan I. Nedelin, the head of Soviet rocket forces. The accident is officially denied until 1990.

March 23, 1961 - Russian cosmonaut Valentin Bondarenko is killed during a routine training exercise. Bondarenko is in a pressure chamber for an eight-day routine isolation test when he discards a cotton ball used to swab a sensor on his body. The cotton ball hits a hot plate used for cooking and catches fire in the oxygen-rich atmosphere. The fire isn't revealed to the public until 25 years later.

July 21, 1961 - USAF Captain Virgil I. "Gus" Grissom's Mercury capsule sinks in an ocean landing after an explosion blows the escape hatch off prematurely. He swims from the capsule safely.

January 27, 1967 - Three U.S. astronauts are killed by a fire during a rehearsal launch for the U.S.'s Apollo 1. USAF Lt. Col. Gus Grissom, USAF Lt. Col. Edward Higgins White and USAF Lt. Commander Roger B. Chaffee. The fire causes a 20-month delay in the first manned Apollo flight. It is believed to have been triggered by a spark from faulty electrical wiring.

April 1967 - Soviet cosmonaut Vladimir Komarov is killed while returning to ground from a successful Soyuz 1 orbit of Earth when the main parachute fails to open.

February 1969 - The Soviet Union's N1 Moon booster explodes during its first test flight, killing 91 people on the ground. The accident is not made public until 1995.

April 13, 1970 - The U.S. lunar mission Apollo 13 loses the use of an oxygen tank necessary to supply air and power. The three-man crew successfully uses the lunar module as a lifeboat, circling the Moon and then returning safely to Earth. It is the first in-flight failure in the U.S. space program.

June 1971 - Soviet cosmonauts Georgi Dobrovolsky, Victor Patsayev and Vladislav Volkov are found dead in their Soyuz 11 spacecraft after an apparently normal landing.

March 1980 - Fifty-one engineers are killed when a Vostok rocket explodes on the launch pad in the Soviet Union.

March 1981 - Two workers are killed in a nitrogen-filled compartment of the Space Shuttle Columbia during a launch rehearsal.

April 1981 - The Columbia's first test launch, in April 1981, is halted in the final seconds of countdown and is delayed for two days because of a software problem. Once it lifts off, everything works but the toilet, which becomes a chronic problem.

September 27, 1983 - A Soviet Soyuz T-10 booster rocket explodes shortly after liftoff. The crew members evacuate using an emergency rocket that parachutes back to Earth.

January 28, 1986 - Seven crew members aboard the Space Shuttle Challenger are killed when the spacecraft explodes shortly after take-off. Christa McAuliffe, Gregory Jarvis, Ronald McNair, Ellison Onizuka, Judith Resnik, Dick Scobee and Michael Smith are killed in the explosion, caused by the failure of O-rings in the shuttle's right solid rocket booster.

January 26, 1995 - A Chinese Long March rocket explodes above its launching pad, killing six people and injuring 23 others. The accident is later determined to have been caused by wind shear.

April 8, 1997 - The Space Shuttle Columbia cuts short its mission 12 days ahead of schedule due to equipment problems. One of the shuttle's fuel cells showed signs of malfunctioning.

June 25, 1997 - During a docking exercise, an unmanned cargo vessel crashes into Mir, disrupting the station's power supply and partially depressurizing the living quarters. The three crew members, two Russians and an American, are not injured.

February 1, 2003 - The Columbia breaks up about 38 miles over East Texas on its return to Kennedy Space Center in Florida. Seven astronauts are killed. The Columbia Accident Investigation Board determines that the cause of the accident was a piece of insulating foam that broke off and struck a hole in the leading edge of the left wing less than two minutes into the flight.

July 25, 2007 - Three employees of Scaled Composites, LLC, are killed in an explosion during a routine test for SpaceShipTwo, a commercial spacecraft sponsored by Virgin Galactic.

July 16, 2013 - During a spacewalk outside the International Space Station, Italian astronaut Luca Parmitano reports a carbon dioxide censor failure in his suit. Between 1 and 1.5 liters of water pool inside the suit and helmet, particularly near his eyes and ears. He is able to make it back to the airlock and is unharmed.