SPACE INTERNET

According to an estimate, 1,250 satellites will be launched annually this decade, with 70% of them for commercial purposes.
Various private companies are aiming to deliver broadband satellite Internet around the world through their fleet of Low Earth Orbit (LEO) satellites.
The idea of a space internet system is not new. It is being used through Geostationary Satellite for selective users.

Important points:

LEO satellites are positioned around 500km-2000km from earth, compared to stationary orbit satellites which are approximately 36,000km away.
Latency, or the time needed for data to be sent and received, is contingent on proximity.
As LEO satellites orbit closer to the earth, they are able to provide stronger signals and faster speeds than traditional fixed-satellite systems.
Additionally, because signals travel faster through space than through fibre-optic cables, they also have the potential to rival if not exceed existing ground-based networks.
LEO satellites travel at a speed of 27,000 kph and complete a full circuit of the planet in 90-120 minutes.
As a result, individual satellites can only make direct contact with a land transmitter for a short period of time thus requiring massive LEO satellite fleets and consequently, a significant capital investment.
Due to these costs, of the three mediums of Internet – fibre, spectrum and satellite – the latter is the most expensive.

Geostationary Satellite Internet:

Geostationary orbit is located at a height of 35,786 km over the Earth’s surface, directly above the Equator
Most of the existing space-based Internet systems use satellites in geostationary orbit.
Satellites in this orbit move at speeds of about 11,000 km per hour, and complete one revolution of the Earth at the same time that the earth rotates once on its axis.
To the observer on the ground, therefore, a satellite in a geostationary orbit appears stationary.
The signals from one geostationary satellite can cover roughly a third of the planet — and three to four satellites would be enough to cover the entire Earth.
Easier Connectivity: As satellites appear to be stationary, it is easier to link to them.
The transmission from a satellite in geostationary orbit has a latency of about 600 milliseconds. The geostationary satellites are located at higher altitudes compared to LEO, thus the longer the distance that needs to be covered results in greater latency.

SOURCE: THE HINDU,THE ECONOMIC TIMES,MINT

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