Space Surveillance Network
The United States Space Surveillance Network (SSN), a division of The United States Strategic Command, has been tracking objects in Earth's orbit since 1957 when the Soviets opened the space age with the launch of Sputnik I. Since then, the SSN has tracked more than 26,000 objects. The SSN currently tracks more than 8,000 man-made orbiting objects. The rest have re-entered Earth's atmosphere and disintegrated, or survived re-entry and impacted the Earth. The SSN tracks objects that are 10 centimeters in diameter or larger; those now orbiting Earth range from satellites weighing several tons to pieces of spent rocket bodies weighing only 10 pounds. About seven percent are operational satellites (i.e. ~560 satellites), the rest are space debris. The United States Strategic Command is primarily interested in the active satellites, but also tracks space debris which upon reentry might otherwise be mistaken for incoming missiles.
A search of the NSSDC Master Catalog at the end of October 2010 listed 6,578 satellites launched into orbit since 1957, the latest being Chang'e 2, on 1 October 2010.
Read more about this topic: Satellite
Famous quotes containing the words space and/or network:
“Here in the U.S., culture is not that delicious panacea which we Europeans consume in a sacramental mental space and which has its own special columns in the newspapers—and in people’s minds. Culture is space, speed, cinema, technology. This culture is authentic, if anything can be said to be authentic.”
—Jean Baudrillard (b. 1929)
“Parents need all the help they can get. The strongest as well as the most fragile family requires a vital network of social supports.”
—Bernice Weissbourd (20th century)