Is it Possible to See Astronauts on the Moon with a Telescope?

The question of whether it's possible to see astronauts on the Moon with a telescope is theoretically intriguing but practically challenging. This article explores the limitations and requirements of such a feat, aiming to provide a comprehensive understanding of the technical aspects involved.

Resolution Limits

The resolution of a telescope is a critical factor in determining how small an object can be distinguished. For an observer to spot an astronaut on the lunar surface, the telescope would need an exceptionally high resolution far beyond what is accessible to amateur astronomers.

According to [1], the resolution of commonly available amateur telescopes is much lower than what would be required. Professional telescopes, such as those used in large observatories, have greater capabilities but still face significant challenges due to the vast distance between Earth and the Moon – approximately 238,855 miles (384,400 kilometers).

Telescope Size

Beyond the limitations of current telescopes, the sheer size of the telescope necessary to achieve the required resolution becomes a formidable obstacle.

From Earth, to observe smaller features like astronauts on the lunar surface, one would need a telescope with a mirror or lens of approximately 250 meters in diameter – about 10 times larger than the Hubble Space Telescope. Achieving this level of resolution would require the telescope to point and track with an accuracy better than one milliarcsecond, while simultaneously compensating for the orbital motion of the Moon and the rotation of the Earth. The telescope would also need to be mechanically isolated from even the smallest vibrations, including those caused by nearby human activity and vehicle movements.

Equipment and Limitations

Specialized telescopes designed for lunar observation can resolve features down to about a kilometer in size. However, these are insufficient to capture the fine details required to spot astronauts. Even high-resolution images from lunar orbiters, such as those from the Lunar Reconnaissance Orbiter, have only captured images of the Apollo landing sites, showing the landers and equipment left behind but not the astronauts themselves.

Given the vast distance, the challenges of atmospheric blurring, and the need for precise alignment, it is highly improbable to see astronauts on the Moon even from an orbiting telescope. The closest real-world example is the Moon Orbiter and its capabilities, which have limitations in observing detailed human activity on the lunar surface.

Conclusion

While it is theoretically possible to observe the Moon's surface features and equipment left behind, seeing astronauts with a telescope from Earth is practically unfeasible. However, with the right combination of telescope size, resolution, and environmental conditions, a telescope on the Moon or in orbit might have a chance of detecting astronauts, but this is currently beyond our technological capabilities.

References

[1] Eso
[2] NASA LRO