NEW DELHI : It was 4.30 am in South Island New Zealand when Matthew Snowden saw “60 or more star-like objects" moving in a line across the sky at the speed of an aircraft. What Snowden was seeing that morning was actually a collection of 60 satellites launched by Elon Musk’s company SpaceX using the Falcon 9 rocket in Florida a few days ago. He posted the same on Twitter.

SpaceX is building a constellation of broadband satellites called Starlink that will orbit closer to the earth’s surface, which is why they can be seen clearly.

This was the fifth such collection to be launched in space by SpaceX since May 2019. Musk intends to put as many as 12,000 such satellites into orbit, while broadband service via satellite is expected to start in the US by mid-2020.

Starlink is facing competition from Richard Branson backed OneWeb, which launched 34 satellites in space, also in February. Its first constellation will include 648 satellites providing global coverage in 2021. Not to be left behind, Amazon plans to launch a constellation of 3,000 broadband satellites that will operate at 590km.

At present, only 5,687 satellites are orbiting space, according to United Nations’ Office for Outer Space Affairs. What separates Starlink and OneWeb from the other is that they are a lot lighter (a Starlink satellite weighs 227kg and a OneWeb satellite weighs 150kg) and orbit much closer to Earth (Starlink will orbit at an altitude of 550km) compared to large navigation and communication satellites that operate in medium earth orbit between 2,000km and 35,000km or the satellites in geosynchronous orbit, which are above 35,000km, have the widest view of the planet, and are used for weather and imagery. Satellites in lower orbit have a small coverage area, which is why a larger number is required to cover a larger area.

“Geosynchronous satellites which are bulky and far away from the earth, which causes signal degradation and the distance incurred more than half-second lag, which is critical for much large business. For these reasons, the use of satellite internet is not widespread," said Sanat K Biswas, assistant professor of electronics and communication engineering, IIIT-Delhi.

The satellite’s distance to Earth is key to the quality of service. The reason existing communication satellites offering internet services are not very dependable is because they are placed far away from the Earth’s surface, leading to issues such as latency and interference. Latency is the time taken by data to travel from transmitter to receiver.

According to a December 2019 report by Deloitte, existing satellite broadband services have median latencies of 594 to 612 milliseconds, which is not favourable for interruption-free online gaming and video-conferencing. Terrestrial broadband services, which use fiber, cable, or DSL (digital subscriber line) to transmit data have a latency of 12 to 37 milliseconds.

With 5G, operators hope the latency will drop to as low as 1 to 2 milliseconds. SpaceX claims Starlink will bring down latencies to as little as 25milliseconds, which is close to the latency in existing 4G services.

In terms of internet speeds, we may not see a huge difference from what existing satellite internet providers like Viasat offer. Viasat is offering speeds of up to 100Mbps using geosynchronous satellites, which is on par with the 4G speeds available today.

The Indian Space Research Organisation also plans to launch higher throughput satellites that can beam high-speed internet at over 300 Gbps. SpaceX strives to offer internet speed of up to 1 Gbps.

While low-flying satellites will ease the latency issue, interference caused by bad weather will remain a problem. “Previously dismissed as limited technology because of high operating costs and latency, as well as the failure of early ventures such as Teledesic, satellite internet has re-emerged in recent years as a viable alternative to the time and energy-intensive practice of laying thousands of miles of fiber optic cable," pointed out Lisa Parks, writer and researcher, in an August 2019 paper on satellite internet services.

A network of such a large number of small satellites will add to the space debris, which is already a major concern among experts. The inter-satellite LASER link of this constellation may also cause problems in the functioning of very large optical telescopes, rued Biswas.

The growing digitization wave and demand for internet services across the world offers a huge opportunity for companies that can provide internet in areas where laying down optic fibre or setting up mobile towers is not feasible. According to a February 2020 report by Cisco, there will be 5.3 billion internet users (66% of global population) by 2023, up from 3.9 billion (51% of global population) in 2018.

Satellite internet will play a critical role in making internet accessible to every home and person, while low-flying satellites will ensure the experience remains consistent. Biswas feels that satellite internet will match the existing speeds of wired and wireless internet by the end of this year when Starlink reaches its initial operational capacity. Remote areas will be beneficial from this service.

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