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.
Many modern GPS receivers use a combination of both GPS and the Russian GLONASS satellites for improved coverage and accuracy. The GPS system currently has 31 active satellites in orbits inclined 55 degrees to the equator. The satellites orbit about 20,000km from the earth's surface and make two orbits per day. The orbits are designed so that there are always 6 satellites in view, from most places on the earth. GPS uses a lot of complex technology, but the concept is simple. The GPS receiver gets a signal from each GPS satellite.