Why are human eyes better at observing the Moon than a camera?

The Artemis II crew is heading home after getting an unprecedented view of the Moon.

Canadian Space Agency astronaut Jeremy Hansen and NASA astronauts Reed Wiseman, Victor Glover and Christina Koch made history by traveling farther than any human has ever traveled from Earth as part of the Artemis II mission.

Satellites have taken pictures of the far side of the Moon since Luna 3 returned first images For the first time, humans observed some distant regions directly with their eyes aboard Artemis II in 1959.

Kelsey Young, NASA’s Artemis II lunar science lead, has long said the team was eager to let humans directly observe and describe lunar features.

“The human eye, especially when it’s connected to a well-trained brain, which I assure you these four people have, is capable of making subtle color observations in the blink of an eye,” Young said during a press conference.

Observations for five hours were done using cameras and naked eyes. The four astronauts gave detailed descriptions of what they were seeing.

One area of ​​particular interest was the Orientale Basin, a region spanning the near and far sides of the Moon. It is believed that it was formed 3.8 billion years ago. Hansen also pointed to color variations extending toward Hertzsprung, a large crater on the far side of the moon.

“We see a brown color and a green color,” Hansen said. “I see the same browns to the west of Orientale, and it’s a huge area, like a piece of a pie, the point of the pie points towards Orientale and then towards the northern part of Hertzsprung.”

It may sound strange that the moon has color, but it does. You can check this by taking a photo and increasing the saturation. The different colors come from different minerals on the moon’s surface.

But the human eye is much more sensitive than the camera. This does not require saturation.

“When you’re looking for subtle differences in color, brightness, etc., the visual system is still much more discriminating than electronic systems,” said Ralph Chow, professor emeritus at the School of Optometry at the University of Waterloo and former president of the Royal Astronomical Society of Canada.

“The second thing is that (the eye’s) photoreceptors have built-in enhancement systems, if you like, that run through the rest of the visual system that sharpen the differences and make them more easily detectable to the human visual system. This is not something that machine vision can do.”

The flip side is that humans are viewing the features in real time and in 3D.

meteorite

One of the more interesting observations from the lunar flyby was the impact of a meteorite on the lunar surface.

On Earth, most meteors burn up in the atmosphere. But the Moon has almost no atmosphere, so no meteorites – small pieces of space rock left over from the solar system’s formation – reach the surface. That is why there are so many huge craters on the Moon.

“We’ve seen three impressive flashes so far,” Glover said during the flight. “I saw two, and Jeremy saw one, of course – oh, Jeremy saw two, so four in total. Of course, the quick effect is flashing.”

NASA’s science chief Young was in Houston and seemed very happy with the news.

Some Apollo astronauts reported seeing the glow in 1969, but those observations were never confirmed.

Peter Brown, Canada Meteorological Astronomy Research Chair and professor at Western University in London, Ontario, said there is another advantage to humans observing the Moon: the ability to see transient events that cameras, with their fast shutter speeds, cannot capture.

“If you’re looking down and there’s darkness in front of your eyes, yes, you’ll see flashes of impact,” he said.

The impact glow from Earth has also been captured.

He said that the European Space Agency is sending a mission called Lunar Meteorite Impact Observer (LUMIO) To see if it can capture Meteorite impact flashes on the far side of the Moon.

This does not mean that cameras are not useful for observing surface features. But combined with visual observations, they can teach us much more about our celestial neighbor.

“It was remarkable to hear the crew describe the stunning views during the flight,” Jacob Bleacher, NASA’s chief exploration scientist at the agency’s headquarters in Washington, said in a news release.

“At first, their descriptions didn’t exactly match what we were seeing on our screens. Now that higher resolution images are arriving, we can finally experience the moments they were trying to share and really appreciate the scientific returns provided by these images and our other research on this mission.”