Footprints and other artifacts from the Apollo missions are still on the Moon. Over half a century after the first landing, the iconic boot print left by Buzz Aldrin remains perfectly preserved. These historical markings, along with rover tracks and discarded equipment, are frozen in time on the lunar surface.
Why Visibility from Earth Is Impossible
Many people ask why powerful telescopes on Earth, including the Hubble Space Telescope, cannot resolve the Apollo landing sites and the footprints. This inability is purely a matter of physics and scale, specifically angular resolution. Angular resolution describes the smallest separation between two objects a telescope can distinguish as separate.
The Moon is approximately 238,900 miles away from Earth, and an astronaut’s footprint is only a few inches wide. Even the largest pieces of equipment left behind, like the descent stage of the Lunar Module, measure only about 12 to 14 feet across. To resolve an object that size at the Moon’s distance would require a telescope mirror with an impractically large diameter, far exceeding the size of any current Earth-based or orbiting telescope.
To clearly distinguish the smallest artifacts, a professional Earth-based telescope would need a primary mirror nearly the size of a football field. The Hubble Space Telescope, while orbiting above atmospheric blurring, has a mirror diameter of only 7.9 feet. This size allows it to resolve objects hundreds of feet across, but not something as small as a lunar lander or a boot print. Direct observation of the footprints from Earth is impossible with current technology.
The Environmental Science of Lunar Permanence
The primary reason the footprints have not eroded is the Moon’s near-perfect vacuum, which results in a complete absence of atmosphere, wind, or liquid water. On Earth, weathering agents like wind, rain, and biological activity quickly erase surface markings. These forces are entirely absent in the lunar environment, meaning there is no wind to blow dust or fill in the depressions left by the astronauts’ boots.
The lunar soil, known as regolith, also contributes to the markings’ permanence due to its unique structure. Regolith is composed of fine, glassy, and abrasive particles created over billions of years by micrometeorite impacts pulverizing rock. When an astronaut stepped on this material, the finely-grained particles compacted and interlocked under the pressure, creating a surprisingly stable and precise mold of the boot.
The main threats to the prints’ long-term survival are the slow, constant processes of solar radiation and micrometeorite bombardment. Micrometeorites continually impact the lunar surface, a process called impact gardening, which gradually churns and overturns the top layer of regolith. This process is extremely slow; estimates suggest it would take tens of thousands to millions of years to completely erase the imprints.
Solar radiation and the extreme temperature swings between lunar day and night cause thermal expansion and contraction of the regolith particles. While this effect is constant, it is not powerful enough to collapse the deeply set, compacted structure of the footprints. The physical imprints of the Apollo missions are expected to remain visible for an immense duration, serving as a geological marker of human presence.
How We See the Footprints Today
Although the footprints cannot be seen from Earth, their existence and condition are regularly verified by an orbiting spacecraft. NASA’s Lunar Reconnaissance Orbiter (LRO), launched in 2009, is equipped with the Lunar Reconnaissance Orbiter Camera (LROC). This system provides extremely high-resolution images of the Moon’s surface. The LRO operates in a low-altitude orbit, flying as close as 13 miles above the surface to achieve the resolution required to image the landing sites.
The LROC has successfully photographed the descent stages of all six Apollo landing sites, and the paths of the astronauts and rovers are clearly visible. While the camera’s resolution is not high enough to capture a crystal-clear image of every individual boot print, the continuous tracks and scuff marks left in the regolith are distinct. The LRO team often captures images when the sun is low on the horizon, creating long, distinct shadows from the equipment and the slight depressions of the tracks.
These shadows dramatically enhance the contrast, making subtle changes in topography, such as the trails left by the astronauts, far more noticeable. The LRO images confirm that the artifacts and tracks remain exactly where they were left, providing definitive visual evidence of the Apollo missions from space. The mission continues to monitor the sites, which are now recognized as protected historical landmarks.