The Artemis II astronauts have completed their historic lunar flyby and taken the pictures to prove it. But as skygazers continue enjoying the images of both the moon and Earth, one question is making the rounds online: If there’s such a space junk problem orbiting our home planet, then why isn’t it visible in any of the newest photos?
It may sound like an odd question, but it’s somewhat understandable. After all, numerous astronomers and researchers continue to sound the alarm on the exponentially growing amount of trash encircling Earth at any given moment. Without any actionable solutions, there is an increasing worry about the possibility of initiating a “Kessler cascade.” In such a scenario, the amount of space junk becomes so ubiquitous that collisions are inevitable. Debris traveling at upwards of 17,500 miles per hour smacks into one another, creating even smaller pieces of trash that then increase the likelihood of similar events. All of that ensuing orbital junk could make it extremely difficult to launch new satellites into space, send astronauts on missions, and even protect Earth’s terrestrial residents.
If all that pollution is so concerning and prevalent, how hasn’t the Artemis II crew documented examples to point it out once they return home? Technically, there is a slight possibility that astronauts could snap a perfect photo pointing out low Earth orbit’s fragility. But when you consider the logistics, the likelihood of pulling off such an image is extremely low. The vast majority of space junk isn’t discernible to the naked eye—especially at the speeds both the junk and astronauts are traveling. Aside from the millions of centimeter-or-larger objects orbiting Earth, around 130 million smaller chunks waste from satellites and rocketry encircle the planet.
[Related: The Great Pacific Garbage Patch isn’t just a floating trash pile]
The altitude varies case-by-case, but the NASA Orbital Debris Program Office estimates the greatest concentration of space junk is floating between 466 and 621 miles above Earth. To put it simply, Artemis II’s astronauts were too busy focusing on the earliest minutes of their launch to take photos outside the Orion capsule’s windows. Within seconds, it became nearly impossible to take pictures of any discernible orbital debris, let alone entire satellites. Imagine taking a photo of a pebble on the highway from even 10 miles down the road. It would be that hard—and that’s before piloting a historic space mission.
This isn’t to say Artemis II hasn’t already had firsthand experience with space junk. The International Space Station often collides with tiny debris, but the habitable capsules’ engineering ensures it can withstand strikes from objects as large as one centimeter in diameter. The Orbital Debris Program Office also estimates encounters with anything larger is “slight” at best.\
The bottomline is this: Space is incomprehensibly vast, but even Earth’s dimensions are difficult to imagine. There is still a lot of wiggle-room for Artemis II and future NASA astronaut crews, especially with the aid of precise computing models and orbital tracking technology. Space junk is a serious problem—but it’s not something to make you worry about crew safety, much less doubt humanity’s latest trip around the moon.
