What is a satellite?
It is basically any object that revolves around a planet in a circular or elliptical path. Earth and moon are 'natural' satellites. Man-made satellites are machines made by people that are launched into space and orbit Earth or another body in space. There are thousands of man- made satellites which may be used to take pictures of our planet, the sun or other objects. These pictures help scientists learn about Earth, the solar system and the universe. Other satellites send TV signals, GPS locations or phone calls around the world.
What is an orbit?
This is a path the satellite follows. In orbit, the farthest point from Earth is the apogee, the nearest is called perigee.
What is space junk?
Approximately 23,000 items of space junk - objects large enough to track with radar that were inadvertently placed in orbit or have outlived their usefulness - are floating above Earth. payloads that enter a wrong orbit or satellites with run-down batteries and left over rocket boosters all contribute to this count.
What are the components of a satellite?
Satellites come in many shapes and sizes, but most have at least two things in common - an antenna and a power source. The antenna is used to send and receive information. The power source can be a solar panel or battery.
Many satellites carry cameras and scientific sensors. They may gather information about Earth's land, air and water or they may collect data from the solar system and universe.
All satellites have a metal or compostie frame and body known as a bus. The bus holds everything together in space and provides enough strength to survive the launch. All satellites also contain an on-board computer to control and monitor different systems as well as an altitude control system which keeps the satellite pointed in the right direction.
What comprises a system?
A system is an integrated set of elements that accomplish a defined objective. These elements include products (hardware, software and firmware), processes, people, information, techniques, facilities, services, and other support elements.
What comprises a sub-system?
A subsystem is a coherent and somewhat independent component of a larger system. Each component is a subsystem of the original system and carries out a part of the system task.