Detail from an Apollo 12 photo showing the deployed flag and its shadow. The latch failed on the pivot designed to hold the top edge of the flag out perpendicular to the pole on a supporting rod, so the flag hung limp. The photo was taken Nov. 19, 1969.
42 years after the first moon rover transported the Apollo 15 astronauts over the lunar terrain, here are a selection of NASA photos taken by Apollo 15 commander David Scott and Lunar Module pilot James Irwin during their wheeled 1971 lunar adventure while Alfred Worden, command module pilot, remained in orbit about the moon.
Shown here, after three highly successful EVAs, Scott walks away from the first ever Lunar Roving Vehicle (LRV), a location where it remains to this day.
(All photos are sourced from NASA's excellent Human Spaceflight Gallery: http://spaceflight1.nasa.gov/gallery/index.html)
An artist's concept of the Apollo 15 Hadley-Apennine landing area showing the two moon-exploring crewmen, Scott and Irwin, driving on the lunar rover.
The lunar rover was attached to the lunar module and lowered to the surface and unfolded by the Apollo surface crew. When packed, the rover took up a volume of only four cubic feet.
Scott and Irwin drive the Lunar Roving Vehicle trainer called "Grover" during a simulation of lunar surface extravehicular activity in Taos, New Mexico.
Scott (right) and Irwin test out the lunar rover before the Apollo 15 mission to the moon at Kennedy Space Center (KSC), Fla., in May 1971.
Gover is driven up to the edge of a man-made crater in Cinder Lake crater field in Arizona to simulate the lunar landscape.
On July 31, 1971, the first lunar rover is unpacked during the first surface extravehicular activity (EVA) at the Hadley-Apennine landing site on the moon. The lunar module, "Falcon," is shown here with the rover and lunar module pilot James Irwin.
The US flag is unfolded and planted toward the end of the Apollo 15 mission; Irwin salutes.
The rover was an invaluable workhorse during the Apollo 15 mission, boosting the scope of how much of the lunar landscape around the Hadley-Apennine landing site the astronauts could explore.
Irwin stops the lunar rover from sliding downhill during the second Apollo 15 lunar EVA. Both of the rover's rear wheels appear to be off the ground. Scott was working on a fresh crater at the Apennine Front (Hadley Delta Mountain) when the vehicle started to slide down the 20 degree slope. Fortunately, the rover was stopped and the astronauts were able to continue their work.
How does a country preserve its mark on the moon for decades to come? It may not seem like the moon is a busy space-traffic hub these days, but in the not-too-distant future, that could change.
On Sunday (Dec. 1), China launched a spacecraft designed to land safely on the lunar surface, and some private companies hope to stage launches to the moon as well. If industry and other nations aren't careful, the uptick in lunar traffic might disturb the landing sites from the Apollo era, as well as Russia's landing sites on the lunar surface.
In order to protect the United States' lunar heritage, U.S. legislators have recently proposed a "moon bill" that would qualify the Apollo landing sites as a national park. However, that could create more problems than it solves, according to a space policy expert. The bill might even violate the United Nation's Outer Space Treaty, an agreement that prohibits countries from owning territory on the moon and other celestial bodies; the United States, Russia and 126 other nations have ratified the treaty. [NASA's 17 Apollo Moon Missions in Pictures]
"They tried to carefully say it wouldn't violate the treaty's sovereignty issues," Henry Hertzfeld of the Space Policy Institute at George Washington University said. "First of all, I think it does, but secondly, even if it doesn't, other nations, including our friends and allies, are going to look at that and say, 'They're declaring sovereignty and violating the treaty.' It's going to be interpreted as yet another aggressive U.S. action."
In a new paper published in the journal Science on Thursday (Nov. 28), Hertzfeld details a potentially better way to preserve the lunar landing sites of nations who have landed on the moon in the past, and those that hope to do so in the future.
Instead of a nation-specific approach to lunar heritage, Hertzfeld and his co-author Scott Pace propose that government officials open lines of dialogue among nations to establish ground rules for how to best maintain every country's mark on the face of the moon.
"The idea is, you leave our stuff alone, we'll leave your stuff alone," Hertzfeld told SPACE.com. "I'm trying not to focus on property rights or specific equipment. I'm just trying to say, at least, for an easy start, to protect what's there, you take every precaution not to mess around with what we have, and we'll do the same thing."
While the United States and other nations already have lines of communication set up to discuss space matters, sometimes issues still arise. NASA's newest moon probe, the Lunar Atmosphere and Dust Environment Explorer (LADEE for short), might run into some issues when China's Chang'e 3 lander touches down on the moon, kicking up dust that could interfere with LADEE's science.
Hertzfeld's international approach might even help ease strained relations between the United States and its fellow spacefaring nations like China and Russia. "If successful, this type of agreement, besides protecting the lunar artifacts, could also help to thaw some of those relationships," Hertzfeld said.
While private enterprise might have particular reasons for reaching the moon, no matter what, they will still need to be affiliated with a government in some way before launching to space, subjecting these companies to international agreements, Hertzfeld said.
"Anybody that would go up in a private company would need a license of some sort from their governments, even if it's just a launch license," Hertzfeld said. "It's really, for the most part, not a private industry question but a government question."
NASA is already working toward protecting its sites and instrumentation on the moon.
In 2011, NASA took steps to make sure that the private groups participating in the Google Lunar X Prize — a $30 million prize going to the first company to land and perform certain tasks on the moon — don't damage the space agency's equipment on the moon, some of which is still gathering science data.
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