As the closest celestial body, the moon has always fascinated humans. We’ve gazed up at it for millennia and aspired for centuries to set foot on its surface. That finally happened in 1969 when U.S. astronauts Neil Armstrong and Buzz Aldrin made their historic Apollo 11 mission to the lunar surface.
Before — and after — Neil Armstrong took that giant leap for mankind, humans have been sending things to the moon and leaving them there. The Apollo missions even contributed to pollution on the moon. There’s estimated to be about 800 items still on the lunar surface. Is it possible to see any of those human artifacts?
What’s Left on the Moon?
The Apollo missions were dedicated mostly to geology, so the more the astronauts left behind, the more rocks they could bring back to Earth. Every Apollo crew left behind seismometers, lots of geological tools, most of their cameras and their lunar module ascent stages. The Apollo 16 crew even left a gold-plated ultraviolet telescope. Apollos 11, 14 and 15 left the Laser Ranging RetroReflectors (LRRR) — and they still work. They’re vital for measuring the distance between the moon and Earth. And of course, Apollos 15, 16 and 17 all left lunar rovers.
In addition to the items from the various Apollo missions, there is another one on our celestial neighbor that has NASA interested. Impact from a rocket body left a series of craters on the moon in March 2022. None of the world’s space agencies claimed credit (or responsibility) for creating these new pockmarks on the lunar surface, so NASA is a bit stumped about their origins.
So, with all of this stuff on the moon, is any of it visible from Earth? And if so, do you need a telescope to see it?
The Optics of Spotting Debris on the Moon
As cool as it would be to gaze up at the moon and see one of the lunar rovers, it’s just not possible. Unfortunately, there is no telescope on Earth powerful enough to spot any of the objects that have been left behind. Not even the Hubble could see what’s left on the moon. It’s designed to collect faint light of galaxies and nebulas, not objects on the moon.
From Earth, we would require a telescope at least 75 feet (25 meters) across to spot a 32-foot (10-meter) object on the moon. And there’s nothing that large on the moon. The proposed Thirty Meter Telescope could make viewing objects on the moon possible, but the National Science Foundation (NSF) just issued its Notice of Intent to prepare an Environmental Impact Statement (EIS) in July 2022, so there is no sure bet the telescope will even be built. The largest optical telescope currently is the Keck Telescope in Hawaii and it is 32 feet (10 meters) across.
Even the massive lunar craters on the moon aren’t visible using the telescopes on Earth; the craters were photographed using the Lunar Reconnaissance Orbiter, an imaging satellite that orbits around the moon about 31 miles (50 kilometers) above the lunar surface.
Originally Published: Apr 1, 2000