A quiet world filled with the history of human exploration, where NASA's abandoned machines helped uncover the secrets of the lunar surface.
Four machines left behind on the lunar surface, and the stories they still tell.
The Moon holds the machines that helped humans take their first steps beyond Earth.
Meet four of them: the Apollo Lunar Modules, the Lunar Roving Vehicles, the ALSEP scientific packages and the Surveyor landers. Each one finished its mission, and each one is still there.
NASA source: Apollo Lunar Module – NSSDC
The Apollo Lunar Module was designed to carry astronauts from lunar orbit to the Moon's surface and bring them back to the Command Module.
It had two main parts:
On July 20, 1969, Apollo 11's Lunar Module, named Eagle, landed in the Sea of Tranquility.
Neil Armstrong and Buzz Aldrin became the first humans to walk on the Moon.
After completing their exploration, they used the ascent stage to return to lunar orbit, leaving the descent stage behind.
The descent stages of the successful Apollo lunar landing missions remain on the Moon.
They represent important historical evidence of humanity's first crewed lunar explorations.
Which part of the Lunar Module carried astronauts back into lunar orbit?
NASA source: Apollo mission – NSSDC
The Lunar Roving Vehicle (LRV) was an electric vehicle designed to help astronauts explore larger areas of the Moon.
Its main purposes were to:
Three Lunar Roving Vehicles were used during Apollo missions 15, 16 and 17 between 1971 and 1972.
After each mission, the astronauts returned to Earth, leaving the vehicles on the Moon.
All three lunar rovers remain on the Moon.
They expanded the distances astronauts could explore and helped scientists collect more geological samples.
How many Lunar Roving Vehicles were used during the Apollo missions?
NASA source: ALSEP – NSSDC
The Apollo Lunar Surface Experiments Package (ALSEP) was a collection of scientific instruments installed on the Moon by Apollo astronauts.
Its purpose was to continue studying the lunar environment after astronauts returned to Earth.
The instruments included:
The first ALSEP station was installed by Apollo 12 in November 1969.
Astronauts from Apollo missions 12, 14, 15, 16 and 17 installed scientific instruments at different lunar locations.
The stations collected data and transmitted information to Earth.
NASA officially ended the ALSEP program on September 30, 1977.
ALSEP helped scientists understand the Moon's internal structure, seismic activity and geological environment.
These instruments demonstrated how scientific equipment could explore another world without requiring a permanent human presence.
What was the main purpose of ALSEP?
NASA source: Surveyor 3 – NASA Science
The Surveyor program was developed to demonstrate that spacecraft could land safely on the Moon.
Its objectives were to:
NASA launched seven Surveyor spacecraft between 1966 and 1968.
Surveyor 3 launched on April 17, 1967, and successfully landed on the Moon on April 20, 1967.
It used a television camera and a surface sampler to examine the lunar environment.
The Surveyor program provided important information for the Apollo missions.
It demonstrated that robotic spacecraft could achieve controlled landings and examine the lunar surface.
Surveyor 3 also became a historic meeting point between robotic and human exploration.
Why was the Surveyor program important?