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Apollo 17 40th anniversary special

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Apollo 17's mission insignia.

Apollo 17 was the final manned mission of the United States’ Apollo space program and, to this day, remains the last time humans stepped foot on the Moon.

The Apollo 17 mission began at 12:33 a.m. EST on December 7th, 1972. On board the mission’s Saturn V SA-512 rocket’s crew capsule were three astronauts, Commander Eugene Cernan, Command Module Pilot Ronald Evans and Lunar Module Pilot Harrison Schmitt.

Apollo 17's crewmembers: Harrison Schmitt, Eugene Cernan and Ronald Evans.

Apollo 17’s mission was to visit the Moon, spend three days on the lunar surface collecting data and samples through a series of instruments, utilise a Lunar Roving Vehicle and perform three extra-vehicular activities (moonwalks). The location for these activities was the Moon’s Taurus-Littrow valley, a lunar valley located on the south-eastern edge of the Mare Serenitatis, a large basaltic plain created 3.8 billion years ago.

The journey to the Taurus-Littrow valley began when Apollo 17 lifted off from launch pad 39-A at the Kennedy Space Center, Florida, an event that was watched by over 500,000 people. The launch was visible from 500 miles away and observers as far away as Miami saw a “red streak” as the rocket took to the sky.

Apollo 17 launching from the Kennedy Space Center.

The Command/Service module of Apollo 17 arrived at the Moon the same day at 2:47 PM EST, before igniting its Service Propulsion System to slow entry and allow orbital insertion. Once the Command/Service Module was positioned in orbit around the Moon, the crew separated the Lunar Module ready for its descent.

At this stage the mission’s crew split into two groups, with Eugene Cernan and Harrison Schmitt accompanying the Lunar Module to the satellite’s surface, and Ronald Evans remaining in orbit to take observations and supply mission data to the surface crew.

Eugene Cernan on the Moon's surface during the crew's first moonwalk.

The Lunar Module successfully touched down on the Moon’s surface at 2:55 PM EST on December 11th. After the Lunar Module had touched down, Schmitt and Cernan configured it for their three-day stay and began preparing for the mission’s first moonwalk (EVA-1).

EVA-1 commenced at 6:55 PM EST, four hours after arrival. This first moonwalk involved both Cernan and Schmitt to offload the Lunar Rover from the Lunar Module, the deployment of the mission’s Apollo Lunar Suface Experiments Package (ALSEP), and the completion of a data-gathering mission across the surrounding region.

Apollo 17's Lunar Rover Vehicle on the Moon's surface; Lunar Module can be seen to the rear.

While traversing across the Moon’s surface, the astronauts gathered 14 kilograms of sample material, took several gravimeter measurements (a piece of technology that allows the local gravitational field to be measured) and deployed two packages of explosives. The explosives – which were later detonated – were used to test geophones (devices that convert ground movement into voltage), allowing the astronauts to derive data about the surface’s structure.

Over the following two days a further two spacewalks were completed by Cernan and Schmitt, with each delivering more samples and data. At the culmination of the final walk, the astronauts collected a breccia (a rock composed of minerals held together by a fine-grained matrix) and dedicated it to each of the nations on Earth who had contributed to the mission.

Harrison Schmitt standing next to a large boulder during the mission's third moonwalk.

Astronauts Cernan and Schmitt successfully lifted off the Moon’s surface in the Lunar Module at 5:55 PM EST on December 14th, successfully rendezvousing with the Command/Service Module for the return journey to Earth. Five days later on December 19th, the Apollo 17 spacecraft re-entered Earth’s atmosphere and landed safely in the Pacific Ocean at 2:25 PM EST.

Post-landing recovery operations of Apollo 17's Command Module.

All three crewmembers were then successfully retrieved from the Command Module and transferred to the nearby recovery ship USS Ticonderoga. Despite the Apollo 17 mission being completed flawlessly and with much public acclaim, it was to be last of the program and, right up until today 40 years later, the last time a human would walk on the Moon’s surface.

Check out HowItWorksdaily.com on Tuesday when we celebrate the 40th anniversary of the last man on the Moon.