The first attempt at a manned lunar landing took place in July 1969. Astronauts Neil Armstrong, Edwin "Buzz" Aldrin, and Michael Collins would repeat the Apollo 10 mission. But when the Lunar Module reached 50,000 feet above the lunar surface, the descent engine fired for twelve minutes and the crew landed on the moon on July 20, 1969. This view shows the complete mission path of Apollo 11 from launch to return to Earth.
Apollo 11 was launched at 9:32 am EDT on July 16, 1969 on a Saturn V rocket.
At 2 hours 44 minutes into the mission, the crew left Earth orbit and headed to the moon by firing their third stage engine for 347 seconds. The crew then separated the Command Space Module (nicknamed Columbia) from the third stage and docked with the Lunar Module (nicknamed Eagle).
The Command Space Module engine fired for six minutes to slow the spacecraft enough to be captured by the moon’s gravity. Later they would burn the engine again to place them in a near circular orbit of 111 km (69 miles). The next day, Armstrong and Aldrin transferred into the Lunar Module and separated from the Command Space Module. On the far side of the moon, they fired their descent engine for 30 seconds to place the Lunar Module at the desired 50,000 foot altitude at the appropriate spot 450km (280 miles) east of the landing site.
On Sunday July 20, 1969, Neil Armstrong and Buzz Aldrin attempted the first lunar landing. The crew making the first lunar landing faced several problems: communications with Earth was intermittent, their position when they fired their descent engine was farther west than they had expected, and their computer stopped several times with data overflow program alarms during the critical landing phase. Finally, as the Lunar Module passed through 600 feet, Armstrong noticed that they were heading for a large crater the size of the Houston Astrodome, filled with automobile-sized boulders. He took over manual control of the Lunar Module and flew over the crater, landing a few kilometers downrange. It seemed forever before we heard the words “Houston, the Eagle has landed.”
Armstrong and Aldrin spent 2.5 hours outside the Lunar Module, collecting 21.5 kg (47.5 lbs) of lunar samples. They erected an American flag, received a call of congratulations from President Nixon, and inspected their Lunar Module, Eagle. They set up a seismometer to measure moonquakes and a laser ranging retro reflector which would be used to determine the distance from the Earth to the moon accurately. Laser beam pulses sent from large telescopes on Earth would be timed as they hit the reflector and were detected when they returned.
Apollo 11 spent 21 hours 36 minutes on the lunar surface. The rocket engine on the ascent stage of Eagle fired for seven minutes returning the astronauts to lunar orbit, leaving the descent stage on the moon. Just over three hours later, the Lunar Module and Command Space Module were docked, allowing the two moonwalkers to transfer themselves and their lunar samples back into the Command Module. Two hours later, Eagle was released, destined to crash into the moon in a couple of weeks.
Apollo 11 left lunar orbit on July 22, 1969 with a 2.5 minute burn of their Service Module engine.
As Apollo 11 approached the end of their flight, they had amazing views of the Earth. The crew of Apollo 11 had successfully fulfilled the challenge set by President Kennedy in 1961: to land men on the moon and return them to Earth safely by the end of the 1960s.
There was no evidence as the third lunar landing mission launched in April 1970 that Apollo 13 would be memorable as a failure. Astronauts Jim Lovell, Jack Swigert, and Fred Haise planned a trip to the moon, and Lovell and Haise expected to land in the Fra Mauro region for a couple days of lunar exploration.
The third landing attempt was canceled 55 hours into the flight when an oxygen tank explosion in the Service Module crippled the spacecraft. The Lunar Module was used as a lifeboat and sustained the crew for 3 days until they could return to Earth.
Apollo 13 was launched at 2:13 pm on April 11, 1970. An engine on the second stage shut down early, forcing the other engines to burn a little longer to get them into orbit.
Two hours thirty-five minutes into the mission, the third stage engine was reignited for a 350-second burn to send the crew on the way to the moon.
Three hours into the mission, the crew separated the Command Serivce Module (nicknamed Odyssey) from the third stage and docked with the Lunar Module (nicknamed Aquarius). After the Lunar Module was extracted from the third stage, Mission Control changed the third stage’s trajectory so that it would impact on the lunar surface. Previous third stages had been sent past the moon into solar orbit. The energy of the impact was detected by seismic instruments left by the Apollo 12 astronauts. Future Saturn V third stages were successfully impacted on the moon.
Not long after extracting the Lunar Module from the third stage, the astronauts looked at the Earth..
In previous lunar orbit missions, the spacecraft was on a free-return trajectory. This meant if for some reason they did not fire their engine to slow into lunar orbit, they would loop around the moon and return to Earth. At 30:40 MET, the crew performed a mid-course correction firing of their engine. This lowered their closest approach point to 60 miles; this was more efficient for getting into lunar orbit, but it meant if something went wrong, they would have to alter their course to get back to Earth.
At 55 hours, 54 minutes, 53 seconds into the mission, an oxygen tank exploded in the Service Module, critically damaging other oxygen tanks and starving the electricity generating fuel cells to a point where they became useless. Looking out the window, the astronauts could see the oxygen venting out into space. Within 90 minutes, the crew and Mission Control accepted the fact that the Command Service Module was dead and the Lunar Module systems had to be used to get the crew home.
To get the crew home, Mission Control devised a way for the crew to use the Lunar Module systems to a) keep 3 people alive for 86 hours and b) perform rocket burns to place the spacecraft on the correct trajectory to return to a safe splashdown in the Pacific Ocean.
One unique aspect of the Apollo 13 mission is that during the 25 minutes the crew was behind the moon out of contact with Earth, they passed 255 km (140 miles) above the backside and set a new record for being the farthest away from earth: 400,171 km (248,655 miles) from Earth; this record holds today.
Five hours before splashdown, the crippled Service Module was jettisoned. The photographs taken by the crew showed one side panel missing due to the explosion.
One hour before reentry, the life-saving Lunar Module was jettisoned. Before closing the hatch between the Lunar Module and Command Module, the crew removed switches, supports, and netting to give to the people at Grumman Aerospace, the Lunar Module’s manufacturer, to say thanks for saving their lives.
Then the Lunar Module was jettisoned, destined to burn up over the Pacific Ocean.
After landing, an investigation determined that the oxygen tank failure was the result of a series of events where it was damaged in handling. Changes were made to the design and an extra tank was added to the Service Module for Apollo 14.
Note: Use the Search feature in SkySafari to find all the Apollo missions on your own. Bring up the Object Info to learn more about each mission.