At noon today, I photographed a small round bright spot next to the sun. What is that? Are they other stars?

When shooting the sun, the small round bright spot appears in the photo because of the reflection of light inside the lens.

When light strikes the interface between two media, it will only reflect but not refract. When light is emitted from a dense medium to a hydrophobic medium, the refraction angle will be greater than the incident angle.

When the incident angle increases to a certain value, the refraction angle will reach 90. At this time, there will be no refracted light in the light-repellent medium, and as long as the incident angle is greater than the above value, there will be no refraction phenomenon.

Extended data:

The surface of different materials has different reflectivity, and its value is mostly expressed as a percentage. The same material can have different reflectivity for different wavelengths of light.

Therefore, when listing the reflectivity of materials, the wavelength should be indicated. For example, the reflectivity of glass in visible light is about 4%, and the selectivity of gold is very strong. The reflectivity near green light is 50%, and the reflectivity to infrared light can reach above 96%.

Baidu Encyclopedia-Reflection