Learn more about space satellite systems

There are more than 1,100 satellites operating outside the universe, including some as big as buses. These are two of a series of interesting features about "space soldiers".

A recent British communications satellite helped identify Malaysia Airlines airline MH370 numbered aircraft.

This satellite has captured signals from missing planes and sent them to experts. The analysis pointed towards the Indian Ocean and helped discover some fragments.

This week, Thailand also said that the country's satellite found that 300 objects could be fragments from the missing plane. These latest findings arouse public interest in the "space personnel" system.

Photo: fineartamerica.com

According to a basic satellite document compiled by Nicholas Johnson, a former expert in the US Aerospace Administration (NASA), there are about 1,100 active satellites in the universe, including satellites. government and private.

The first satellite launched into space was Russia's Sputnik 1 in 1957 while the "oldest" satellite is still active, launched in 1958.

Space satellites are owned by governments or private enterprises. Leading the number of satellites operating in space today is USA with 502 units, followed by Russia and China with 118 and 116 satellites respectively.

The satellites launched into space perform many different tasks including global positioning, telephone or television signal transmission, weather forecast, defense, scientific research and even service activities. agricultural production.

Depending on the task, the satellite has different sizes.

Some telecommunications satellites can be as big as a small school bus and weigh up to 6 tons while short-term satellites are about 10cm ² and weigh about 1kg.

The work of a satellite also determines its position in space. Satellite communication is usually about 35,400km from the ground, the satellite locates about 20,000km. Some satellites are not in a fixed position but move in space when needed.

With about 2,600 deactivated satellites still floating in space, there is a threat of collisions between "dead" satellites and active satellites.

To minimize this risk, programmers who let low-level satellites at the end of their missions will automatically return to Earth and self-destruct within 25 years. As for satellites at high altitudes, they will continue to be pushed farther up into space.