How Many Satellites Are Orbiting the Earth?

Artificial Satellite: An unmanned spacecraft orbiting the earth in space orbit. The artificial satellite basically moves around the earth according to the laws of celestial mechanics, but the actual motion is very complicated because it is affected by the non-spherical earth's gravitational field, atmospheric resistance, solar gravity, lunar gravity and light pressure in different orbits. Artificial satellites are the most widely launched and fastest-growing spacecraft. The number of satellite launches accounts for more than 90% of the total spacecraft launches. ^[1]

Divided by running track

Low orbit satellite, medium orbit satellite, high orbit satellite, geosynchronous orbit satellite, earth

Universal system has structure, temperature control,

In the satellite system, various equipments are classified as effective according to their functions.

First, how to determine the use of artificial satellites?

The composition of artificial satellites can be basically divided into two parts: "satellite body" and "payload". A payload is an instrument used by a satellite to perform experiments or services, and the satellite itself is a vehicle that maintains the operation of the payload. The use of a satellite depends on the payload it carries.

2. What are the types of artificial satellites? What is the use?

The advantages of artificial satellites are that they can simultaneously process a large amount of data and can be transmitted to any corner of the world. Using three satellites can cover all parts of the world. According to the purpose of use, artificial satellites can be roughly divided into the following categories:

Science Satellite: Enter

The world's first artificial satellite

Large high-precision artificial satellite tracking designed by Baker and Nunn in the 1950s

In April 2015, NASA released images taken by the "Visible and Infrared Spectrometer" (VIRS) carried by the messenger spacecraft, showing some objects on Mercury's surface that may be volcanic pipes or fresh impact craters. To highlight geological features, these images were superimposed with black and white images from the Mercury Dual Imaging System (MDIS) on the messenger probe.

NASA's Messenger Mercury probe actively dropped on Mercury's surface. The exact time of the impact will be at 3:30 am on May 1, 2015. However, when the impact occurs, the courier spacecraft will be on the back of Mercury and will not be visible from Earth. The image returned by the messenger spacecraft can see a cliff with a height of 2 kilometers, which cut through a crater named "Duccio". This is a compressive fault formed during Mercury's early cooling and shrinking process, and it is a reflection of the strong internal stress acting on the surface.