Editing Apollo 15 (section)

==== Second and third EVAs ====
[[File:Apollo 15 Genesis Rock.jpg|thumb|right|alt=A white rock, placed in a laboratory setting|The [[Genesis Rock]]]]

The rover's front steering, inoperative during the first EVA, worked during the second and third ones.{{sfn|Mission Report|p=101}} The target of the second EVA, on August 1, was the slope of Mons Hadley Delta, where the pair sampled boulders and craters along the [[Montes Apenninus|Apennine Front]]. They spent an hour at [[Spur (lunar crater)|Spur]] crater, during which the astronauts collected a sample dubbed the [[Genesis Rock]]. This rock, an [[anorthosite]], is believed to be part of the early lunar crust—the hope of finding such a specimen had been one reason the Hadley area had been chosen. Once back at the landing site, Scott continued to try to drill holes for experiments at the ALSEP site, with which he had struggled the day before. After conducting soil-mechanics experiments and raising the [[Lunar Flag Assembly|U.S. flag]], Scott and Irwin returned to the LM. EVA{{nbsp}}2 lasted 7{{nbsp}}hours and 12 minutes.{{sfn|Chaikin|p=598}}<ref name=summaryalsj group=ALSJ/>

Although Scott had eventually been successful at drilling the holes, he and Irwin had been unable to retrieve a core sample, and this was an early order of business during EVA 3, their third and final moonwalk. Time that could have been devoted to geology ticked away as Scott and Irwin attempted to pull it out. Once it had been retrieved, more time passed as they attempted to break the core into pieces for transport to Earth. Hampered by an incorrectly mounted vise on the rover, they eventually gave up on this—the core would be transported home with one segment longer than planned. Scott wondered if the core was worth the amount of time and effort invested, and the CAPCOM, Joe Allen, assured him it was. The core proved one of the most important items brought back from the Moon, revealing much about its history, but the expended time meant the planned visit to a group of hills known as the [[North Complex]] had to be scrubbed. Instead, the crew again ventured to the edge of Hadley Rille, this time to the northwest of the immediate landing site.<ref name=summaryalsj group=ALSJ />

[[File:Apollo 15 feather and hammer drop.ogv|thumb|alt=Video of an astronaut dropping a hammer and a feather while on the Moon|David Scott's hammer and feather experiment]]
Once the astronauts were beside the LM, Scott used a kit provided by the [[United States Postal Service|Postal Service]] to cancel a [[first day cover]] of two stamps being issued on August 2, the current date.<ref group=ALSJ name=hammer>{{cite web |url=https://history.nasa.gov/alsj/a15/a15.clsout3.html |title=The Hammer and the Feather |year=1996 |editor-last=Jones |editor-first=Eric M. |work=Apollo 15 Lunar Surface Journal |publisher=NASA |access-date=December 21, 2018 |archive-url=https://web.archive.org/web/20181230031714/https://history.nasa.gov/alsj/a15/a15.clsout3.html |archive-date=December 30, 2018 |url-status=live |df=mdy-all }}</ref><ref>{{cite web|title='Moon Mail' and Space Stamps Now on Display in World's Largest Postal Gallery|last=Pearlman|first=Robert Z.|date=September 24, 2013|url=https://www.space.com/22918-moon-mail-space-stamps-on-display.html|publisher=Space.com|access-date=December 21, 2018|archive-url=https://web.archive.org/web/20181221182858/https://www.space.com/22918-moon-mail-space-stamps-on-display.html|archive-date=December 21, 2018|url-status=live|df=mdy-all}}</ref> Scott then performed an experiment in view of the television camera, using a falcon feather and hammer to demonstrate [[Galileo]]'s theory that all objects in a given gravity field fall at the same rate, regardless of mass, in the absence of [[aerodynamic drag]]. He dropped the hammer and feather at the same time; because of the negligible lunar atmosphere, there was no drag on the feather, which hit the ground at the same time as the hammer. This was Joe Allen's idea (he also served as CAPCOM during it) and was part of an effort to find a memorable popular science experiment to do on the Moon along the lines of Shepard's hitting of golf balls. The feather was most likely from a female [[gyrfalcon]] (a type of falcon), a mascot at the [[United States Air Force Academy]].<ref group=ALSJ name=hammer />

[[File:Fallen Astronaut.jpg|thumb|left|alt=A small aluminum statue and a plaque on the lunar surface|The ''[[Fallen Astronaut]]'' memorial, near Hadley Rille, Moon]]
Scott then drove the rover to a position away from the LM, where the television camera could be used to observe the lunar liftoff. Near the rover, he left a small aluminum statuette called ''[[Fallen Astronaut]]'', along with a plaque bearing the names of 14 known American astronauts and Soviet cosmonauts who had died in the furtherance of space exploration. The memorial was left while the television camera was turned away; he told Mission Control he was doing some cleanup activities around the rover. Scott disclosed the memorial in a post-flight news conference. He also placed a Bible on the control panel of the rover before leaving it for the last time to enter the LM.<ref group=ALSJ name=hammer />

The EVA lasted 4 hours, 49 minutes and 50 seconds.{{sfn|Mission Report|p=16}} In total, the two astronauts spent 18{{frac|1|2}} hours outside the LM and collected approximately {{convert|77|kg|lb|abbr=on|order=flip}} of lunar samples.<ref name=summaryalsj group=ALSJ/>