Apollo 15

Apollo 15 was the fourth mission to land men on the Moon. It was the first mission to use a lunar rover, to feature three EVAs and to launch a subsatellite in lunar orbit. It was the ninth manned mission in the Apollo Program.

The Apollo 15 Crew :

1.  David R. Scott (Commander)
He was also the Pilot on Gemini VIII (March 16, 1966) and  Command Module Pilot on Apollo 9 (March 3-13, 1969).

2. James B. Irwin (Lunar Module Pilot)

3. Alfred M. Worden (Command Module Pilot)

The crew for Apollo 15 had previously served as the backup crew for Apollo 12.

The Apollo 15 Backup Crew were:
- Richard F. Gordon (Commander)
- Vance Brand (Command Module Pilot)
- Harrison H. Schmitt (Lunar Module pilot)

Mission

The aims of the mission were:

1. To explore the lunar surface, survey and sample material in the Hadley-Apennine region.

Exploration and geological investigations at the Hadley-Apennine site were enhanced by the addition of the lunar rover that allowed Scott and Irwin to travel greater distances from the LM than they could on foot during their three EVAs.

2. To make engineering evaluations of new Apollo equipment.

With an additional battery and more life support supplies, the redesigned Apollo LM could make longer missions. This alteration resulted in moon exploration time being doubled to almost 67 hours. The crew benefited from an improved spacesuit. A diagonal entry strip enabled an additional hip joint to be inserted. This enabled the wearer to bend over and to sit in the rover. It also allowed the astronauts to spend more time outside the lunar module.

3. To set up and activate lunar surface scientific experiments.

The Apollo lunar surface experiment package (ALSEP) was the third operating ALSEP along with Apollo 12 and 14.

4. To conduct lunar orbital experiments and photographic tasks.

Before launch, the crew had received intensive in-the-field training by Caltech geologist Lee Silver. This was aimed to help the astronauts describe the lunar geology to Earth-based scientist and would greatly increase the effectiveness of the EVA crew.

Apollo 15 was launched on a Saturn V rocket from the Kennedy Space Center, Florida at 9:34am EST on July 26, 1971. The Command Service Module was called Endeavour and the Lunar Module was called Falcon.

Falcon Lunar Module landed on the moon 6:16pm EDT on July 30 1971. The Apollo 15 landing site was Hadley-Apennine region near Apennine Mountains (27N 4E).

Commander David Scott and Lunar Module Pilot James Irwin spent three days on the Moon on the lunar extra-vehicular activity (EVAs, Moonwalks), while Command Module Pilot Alfred Worden conducted observations aboard the orbital module.

Moon Exploration

The astronauts completed three EVAs, one each day for three separate days, spending more than 18 hours on the lunar surface. They travelled a total 17 miles (27km) in the rover, exploring the beautiful canyon of Hadley Rille, plains and deltas. They set up an ALSEP and gathered 76.6 kgs (169 lbs) of interesting rocks, including  the "genesis" rock, thought to date from the early solar system and a rock that contained tiny spheres of green glass.

During the third EVA, commander David Scott dropped a feather and a hammer at the base of Mount Hadley Delta. This was to demonstrate that in an airless environment, all objects fall at the same speed regardless of weight.

Liftoff of the LM ascent stage occurred on August 2. After Falcon's return to Endeavour, the LM was crashed in the surface to calibrate all three ALSEP seismometers. Then a scientific satellite was launched from Endeavour into orbit around the Moon. This was the first time a satellite was left in lunar orbit. It continued to send date to Earth for nearly a year.

On the way back to Earth (5 August 1971), Apollo 15 astronaut Alfred M. Worden conducted the first space walk between Earth and the Moon to retrieve film from the side of the spacecraft. He became the first human to take a walk in deep space about 197,000 miles (317,041km) from Earth. The walk lasted about 16 minutes.

Earth Landing

During Earth re-entry and descent, one of the 3 parachutes failed to open fully. As a result, descent velocity was 4.5km/hr (2.8mph) faster than planned. The Command Module splashed down at 4:45pm EDT on August 7, 1971 in the Pacific Ocean. The recovery ship was USS Okinawa.

Summary Stats of the Mission

Lunar Orbits: 74 revolutions (145 hours)
Duration: 12 Days, 17 hours, 12 min
Lunar Location: Hadley-Apennine
Lunar landing Co-ordinates: 26.08 degrees North, 3.66 degrees East.
Time on Lunar Surface (total): 66 hr. 54 min. 53 sec.
Mission Duration: 295 hr. 11 min. 53 sec.
Lunar Rover Weight: 209kg

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