Another revolutionizing element that the satellites brought was cellular telephones. These telephones have made communication not easy but handy too. Staying connected is easy as a pie with these phones. In the year, 1976 February, COMSAT launched MARISAT, a new type of satellite for offering mobile services to US Navy and all other marine clients. And in no later time, Europeans also commenced MARECS series for providing same services in 1980. Maritime organization UN international had funded INMARSAT in year 1979. And INMARSAT leased MARECS and MARISAT satellite transponders initially but soon in 1990 October started its own satellite named INMARSAT II F-1. Third generation of the satellite has been commenced too.
The contract of building an aeronautical satellite was given to General Motors in mid 1970s but was cancelled soon and IMARSAT provided the service. Perceived as means of offering traffic monitoring and telephone services on ships initially but it has offered a lot more than that. Gulf War brought the technology to public notice.
Many companies have worked hard to present version of Personal Communication System with the use of satellites in the Low Earth Orbits (LEO). As compared to initial LEO satellites, these systems orbited around 500 miles below belt. Among most ambitious LEO systems, Iridium by Motorola ruled the roost. At an altitude of 400 miles, it planned to start 66 satellites in the polar orbit. All the six orbits had 11 satellites each. And it started offering communication services of the cellular phones back in 1998. Apart from the large scaled LEO systems, there were many small ones too. But these companies planned to provide limited services, basically radio and data determination. Classic of these was known as ORBCOM which has now become a global leading provider of cellular data communications based asset management, tracking and remote controlling.
By 20th century’s end, around 2,200 satellites were orbiting the planet with many of them offering scientific data with shots of earth that were not even imagined before. Along with latest imaging techniques, satellites bestow ordinary human beings with super sight. Remote sensing uses aerial photography and lets humans’ view, which is otherwise not possible with an unaided eye. Different techniques allow identification of vegetation, soil, seasonal crops, mineral resources and changes brought around by floods and storms. These are also use for detecting surface temperatures, finding out groundwater movements. The key ability of remote sensing device is that it can see energies in the wavelength that is not visible to the human eye. Remote sensing, which is just a step child of space age, is prying many innermost secrets of Earth.