The Apollo 11 Moon landing took place 50 years ago today, at 20:17 UTC (21:17 BST).
I remember it quite well, because as a student without a TV set back then, I listened to it on the radio, and heard the words: “That’s one small step for (a) man, one giant leap for mankind,” as Neil Armstrong stepped onto the surface 6 hours later.
And it was indeed a giant leap. I thought so then, and still think so now.
I’ve never been a moon landing sceptic, although I can understand why some people might have been sceptical: it was a rather impossible sort of thing to have done. But if the moon landing actually did happen, the lunar descent module will still be on the surface of the Moon at Tranquility Base, exactly where it landed, and so will the US flag, and all the footprints the astronauts left on the dusty surface. If so, it should be quite easy take photos of the site from a Moon-orbiting satellite.
One day that site might even become a tourist destination, enclosed by a dome.
I’ve started watching a documentary video about Apollo 11:
It starts with the JFK speech in which he said that “we choose to go to the Moon… not because it is easy, but because it is hard.” In retrospect it seems to me that he could have equally well said “not because it is hard, but because it is easy.” After all, space travel had been getting easier and easier over the previous two decades in exactly the same way that air travel had also been getting easier and easier. The first time I flew from England to Brazil it was in a slow, noisy propeller plane, and the last time I flew back it was in a fast, much quieter jet plane: it was getting easier all the time.
The Apollo 11 astronauts discarded gadgets, tools, and the clothesline contraption that moved boxes of lunar samples, one by one, from the surface into the module. They left behind commemorative objects—that resplendent American flag, mission patches and medals honoring fallen astronauts and cosmonauts, a coin-size silicon disk bearing goodwill messages from the world leaders of planet Earth. And they dumped things that weren’t really advertised to the public, for understandable reasons, such as defecation-collection devices. (Some scientists, curious to examine how gut microbes fare in low gravity, even proposed going back for these.)
Fifty years later, of everything that remains at the cosmic campsite, the American flag has had the worst time of it.
The flag is no longer standing. In fact, it’s been flat on the ground since the moment Aldrin and Neil Armstrong lifted off. As the Eagle module ignited its engines and rose, spewing exhaust around, Aldrin caught a glimpse of the flag falling from his window.
The flag, made of nylon, was an off-the-shelf purchase. Unlike Earth, the moon lacks an atmosphere capable of blocking out the worst of the sun’s rays. It wouldn’t have taken long for the ultraviolet light to eat away at the dye and bleach the flag white. “Have you ever seen burnt newspaper from a fireplace? All the color is gone and everything,” says Dennis LaCarrubba, who worked at the New Jersey–based company that manufactured the flag. “That’s probably what the flag would look like now.”
The photographic evidence for this came decades later, thanks to NASA’s Lunar Reconnaissance Orbiter, a spacecraft that still circles the moon today. The spacecraft’s camera photographed several Apollo landing sites. The NASA astronauts who flew to the moon in the late 1960s and early 1970s always brought American flags with them. In photos of later Apollo missions, you can see, amid all the pockmarked gray terrain, a little white smudge and, right next to it, a slightly bigger, black smudge—a flag, faded from the glow of the sun, and its shadow.
Scientists long thought that the sun exposure would cause the fabric to disintegrate, reducing the little monuments of American achievement to dinky poles surrounded by fibers. But the orbiter photos suggest that the fabric has withstood the conditions.
The photos also provide some defense against people who believe the moon landing was faked. Julie Stopar, a scientist at the Lunar and Planetary Institute and a member of the lunar orbiter’s imaging team, carries postcards of the landing sites in case she runs into someone with doubts, including her own friends and family. “They’ll ask me jokingly—and in some cases, not so jokingly—‘Are you sure we really landed on the moon?’ And it’s like, ‘Yes, I am sure. I’ve seen it, and we have pictures of it,’” Stopar says. “And then I’ll show them the pictures and then they’re like, ‘Oh, okay, I guess that’s pretty convincing.’”
The resolution of the orbiter’s cameras isn’t strong enough to make out the Apollo astronauts’ boot prints, but some were no doubt blasted out of existence when the exhaust of the Eagle’s engines slammed into the regolith. Subsequent Apollo missions captured footage of the turbulent experience of liftoff. “You can see a severe blowing occurring; you can see flags flapping in the wind like it’s a hurricane; you can see dust lifting off the surface everywhere,” says Phil Metzger, a planetary scientist at the University of Central Florida.
The tracks outside of the blast zone were likely undisturbed, though, and most anything made with metals—the lower half of the Eagle, a seismometer, commemorative plaques, assorted tools—has probably fared well on the moon. The module’s gold foil, which provided warmth for its passengers, has probably faded and splintered. And one of the experiments is still going.
Armstrong and Aldrin placed on the surface a boxy array of mirrors designed to reflect incoming light back to its source without significantly scattering. Several times a month, Tom Murphy, a physics professor at the University of California at San Diego, instructs a telescope in southern New Mexico to beam a laser at the instrument. The light sprints home in two and a half seconds. “The photons that we make in our laser go out, touch these reflectors, and come back to us and report,” says Murphy, who uses the measurements to study the fundamentals of gravity.
The mirrors still provide good data, but they don’t work like they used to. Murphy suspects that they’re covered in dust, which degrades their reflectivity, especially during a full moon, when particles absorb the direct sunlight and leave little for the mirrors. During an eclipse, when the near side of the moon is in darkness, the reflectors return to their old glory.
No one has ever returned to the site of Apollo 11. No one has been on the moon’s surface at all since 1972, but national governments, commercial companies, and nonprofits alike are hoping to make it.