Man-made satellites are important and impressive pieces of technology, but they do have some down sides. Satellites are very costly, hard to maintain, and not always reliable. These disadvantages have to be weighed against the many benefits from satellites. They take photographs of various things on Earth and in space, in visible light or in other areas of the electromagnetic spectrum, and send and receive a variety of signals for televisions, cell phones and GPS devices.
Costs are Prohibitive
Satellites are expensive. In addition to the cost of building one of these devices, there is also the cost of launching the satellite into space. Satellites are costly even when they are successfully launched, but all too often, launches end in failure. In 2017, the billion-dollar spy satellite, Zuma, was lost when the rocket carrying it failed to reach orbit height. Satellite costs may rise as satellite technologies grow more complex to handle different purposes.
Signal Reception can be Spotty
Another problem with satellites is their somewhat unreliable signal. There are different factors that affect the strength and reception of a satellite signal. Errors might be made by the satellite or anyone working on it. This can cause a variable level of interference to the signal. There are also circumstances, such as weather or sunspots which may be impossible to alter, that affect the satellite's signal. All these things can cause interference and make proper operation of the satellite very difficult.
Propagation Delay is a Problem
Propagation delay is the term used to describe the length of time it takes for the satellite to communicate with Earth. This delay can vary greatly. More than anything else, this is caused by the huge distance over which the satellite must send the signal. The time can vary between 270 milliseconds to reach the satellite from Earth and return again to 320 milliseconds. This delay can cause an echo over telephone connections.
There are No Repair Shops in Space
Satellites used to be impossible to maintain or repair in any way. Only with the successful repair of the Hubble Telescope did that change, when NASA astronauts used the space shuttle to rendezvous with the telescope and repair some faulty equipment. However, it is still extremely difficult to repair a satellite. NASA is designing robots whose sole purpose would be to repair satellites. The operation is being handled by a department at NASA called the Satellite Servicing Development Office.