A memoir is a type of autobiography wherein the main content of a written material is about the writer.It is a genre of literature that involves writing about certain aspects and concerns of a personâs life. memoir is a type of autobiography wherein the main content of a written material is about the writer.
There have been about 8000 man made objects launched into space - only a handful left Earth orbit. Some have decayed and reentered. There are about 3000 satellites currently in orbit. Only about 1000 of those are active. But there are other objects, too, such as spent rockets. Some objects have broken apart because of collisions. There are about 20,000 objects in orbit that are 10 cm in diameter, or larger.
Currently, a total of 31 GPS satellites orbit the earth twice a day. 1959 The Navy built the first real satellite navigation system, which it called TRANSIT. The system was designed to locate submarines, and started out with six satellites and eventually grew to ten. The subs often had to wait hours to receive signals from the satellites, but the model set the stage for true GPS with continuous signaling from satellites in space.