Does the moon shine because it emits its own light? No, that's not true: The light we see coming from Earth's satellite is sunlight reflected off its surface, not the moon's own emitted light.
The claim appeared in a video on TikTok (archived here) published by @stefan197940 on February 9, 2024.
The Bulgarian text, translated into English by Lead Stories staff, reads:
This lighthouse is not a rock covered in dust.
Just like the moon, the lighthouse emits its own light.
This is what the post looked like on TikTok at the time of writing:
(Source: TikTok screenshot taken on Tue Mar 5 06:35:03 2024 UTC)
The claim was made on a TikTok channel rejecting official science and supporting numerous conspiracy theories based on pseudoscientific beliefs including that the Earth is flat. According to science, the moon does not emit its own light, as seen here (archived here). The light we see coming from the moon is only reflected light (archived here) from the sun's surface.
Planets also do not produce their own light. They reflect light the same way the moon does. That is why the planets in our solar system also look like shining stars in the night sky, because of their reflected sunlight (archived here).
According to NASA, seen here (archived here), of the sunlight that reaches the surface of the moon, only one-tenth is reflected back into space. In comparison, because much of the surface of our planet is water, the Earth reflects much more sunlight than the moon and reflects around three-tenths of the sunlight back into space.
The International Space Station (ISS) (archived here) proves that celestial bodies that do not emit their own light can appear as bright objects in the sky due to reflected sunlight. The ISS is visible as such a bright object in the night sky because of its solar panels, which reflect a significant amount of sunlight. Despite its artificial origin, similar to the moon, the light reflected from the station's surface turns it into a luminous object in the sky. In fact, due to the large amount of reflected light, the ISS is one of the brightest objects in the night sky, as seen here (archived here).
