Traditional Culture Encyclopedia - Photography major - What is a deep space object?

What is a deep space object?

"Deep space" is a space technical term, which means:

1. Space far beyond the boundary of the earth's atmosphere, including space outside the solar system.

2. The distance from the earth is equal to or greater than 2× 10E6 km.

Deep space object (DSO) is a common term in amateur astronomy. Generally speaking, deep space objects refer to objects other than solar system objects (planets, comets, asteroids) and stars. Most of these celestial bodies are invisible to the naked eye. Only brighter celestial bodies (such as M3 1 Andromeda galaxy and M42 Orion nebula) can be seen by the naked eye, but there are few. More than 100 deep space objects can be seen with binoculars, such as most of the objects in the catalogue of messier nebula clusters compiled by French astronomer messier in the18th century. If there is an astronomical telescope, the number of deep space objects that can be seen will greatly increase. Quite a few deep space objects can be photographed by astrophotography.