If you want to land on another world, map it first. Since the two Viking missions in the 1970s, we have extensively charted the surface of Mars and the Mars Reconnaissance Orbiter spacecraft — equipped with the HiRISE Camera -- is now resolving objects a meter in size. We could spot a Martian from space, barely, if we knew where to look.
Someday, Lord willing, humanity will go to Mars. The HiRISE images will guarantee that we know what the landing site looks like, and that there will be no unpleasant surprises, like huge boulders or deep ravines that would make a Martian lander topple over.
Starting in 1961, the United States similarly mapped the moon in preparation for the Apollo missions. Before we sent astronauts, a series of Ranger and Surveyor landers characterized the lunar regolith (soil) as firm enough to land and walk on. But craters of every size pockmarked the surface. So we launched five Lunar Orbiter missions, and their powerful cameras carefully mapped the entire Moon to a resolution of a few meters.
NASA engineers and scientists used these images to select landing sites for the Apollo missions. A prime landing zone would be flat and would have no large craters or boulders that could overturn the lunar module (LM) lander upon touchdown. For this reason the smooth Sea of Tranquility was selected as the target for Apollo 11.
But what if you miss the landing zone?
Commander Neil Armstrong and lunar module pilot Buzz Aldrin did. Descending too fast in humanity’s first approach to the moon’s surface, they overshot their target by about four miles. That’s not bad, given no one had ever done it before this real-time test and they had been traveling for a quarter of a million miles. Four miles out of a quarter million was pretty good for these pilots.
But as Aldrin and Armstrong approached the lunar surface, Neil Armstrong realized that the lander was descending to an area littered with large boulders. To land there might be catastrophic. Using manual control, he delayed the landing by firing the engine to keep the LM aloft at about 400 feet to wing it to a landing site with few boulders or craters — like the large one ahead of them. Would they clear it?
More importantly, would they have the fuel to clear it?
You have free articles remaining.
A spacecraft must have the smallest mass possible, so the Eagle had very little extra fuel to burn on a search for a better landing site. As Armstrong looked, Flight Director Gene Krantz announced that the LM had 60 seconds of fuel remaining. Was the fuel gauge accurate? Still they looked. As they cleared what would later be named West Crater, Armstrong saw that the other side of it was relatively featureless, so he decided to land there. 45 seconds. Still not landed, but descending, very close. Armstrong’s heart rate was 158, his body belying his cool demeanor.
With about 20 seconds of fuel left, Buzz Aldrin announced, “Contact Light,” as the LM touched the lunar surface and the engine shut down.
Consummate professionals, Aldrin and Armstrong did not whoop and holler. After a 19-second, matter-of-fact exchange between Mission Control and the Lander, Armstrong announced, “Houston, Tranquility Base here. The Eagle has landed.”
CAPCOM Charlie Duke responded from Mission Control: “Roger, Tranquility. We copy you on the ground. You got a bunch of guys about to turn blue. We’re breathing again. Thanks a lot.”
Gene Krantz called out to all stations in Mission Control to give the Stay/No Stay response and all stations declaimed “Stay.” We had truly landed on the Moon. The astronauts later began their excursion on the lunar surface and returned home four days later, the upper stage of the Lunar Module powering them off the surface of the Moon to dock with the Command Module piloted by the intrepid Michael Collins.
What a spacecraft was the LM! Has any more absurd or outrageous flying machine ever been devised? An unsung mechanical hero of the Apollo program, it was splendidly designed and constructed by the Grumman Corporation. It didn’t need to be streamlined for the vacuum of space, but it needed the smallest mass possible for its maneuvers. Parts of the walls were the thickness of soda cans. Because glass is heavy, the engineers changed the window design until there were just tiny triangular windows. The original LM design was rounded, but slicing off parts of it yielded those peculiar sharp edges — and lower mass. They didn’t even provide seats for Aldrin and Armstrong.
America should be proud of what it accomplished with the moon missions, even if we never again spend that kind of money on human space flight.
In his essay, “Religion and Rocketry,” C.S. Lewis said that if humans conquer space we will do it as oppressors and plunderers. We are a fallen race — original sin is empirically proven by humanity’s spotty track record. We should take his cautions seriously.
Indeed, we landed on the moon in part because we wanted to win the Cold War against the Soviets, each nation wanting to prove the technological superiority of its form of government. The rockets that carried the astronauts were adapted from technology that would have enabled us to throw megaton-class hydrogen bombs at each other. The space race was a non-violent way to wage that war.
America’s race to the moon was a public affair; everyone saw the failures and the successes along the way. We showed that a free and open society could perform great feats. But when we got there, the astronauts did not talk about manifest destiny, victory on the battlefield, or making a lot of money by destroying the environment.
Instead, they left a plaque on the lunar surface that read, “Here men from the planet Earth first set foot upon the Moon, July 1969 A.D. We came in peace for all mankind.”