Technology
Srikanth Ramakrishnan
Feb 26, 2018, 03:25 PM | Updated 03:07 PM IST
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Engineer and inventor Elon Musk has many a plan for a futuristic world. Among all of his ventures, however, stands out one that will affect more than a few people. Musk’s company SpaceX is working on a satellite constellation that will drastically alter connectivity to the internet in a major way.
Meet Starlink
Starlink is SpaceX’s project that aims to set up a satellite constellation in orbit as part of a space-based communications system. It would create a satellite bus – a model where multiple satellites or spacecraft is used – to create a network. SpaceX had in 2016 and 2017 filed applications with the United States’ Federal Communications Commission (FCC) for two constellations with 4,425 and 7,158 respectively. The company aims to have 11,943 satellites in orbit by 2020. Yes, nearly 20,000 satellites will be in space for communications, primarily broadband.
Another constellation – OneWeb by WorldVu Satellites – has also been proposed since 2014 to send 882 satellites in to space to get them operational as early as 2019.
Now, the interesting thing is that these satellites are all small and two of them have already been launched this month.
Introducing The Tintins
The first of the two prototype satellites, Tintin A and Tintin B were launched on 22 February this year aboard a Falcon 9 rocket whose primary payload was the Spanish Paz satellite.
First two Starlink demo satellites, called Tintin A & B, deployed and communicating to Earth stations pic.twitter.com/TfI53wHEtz
— Elon Musk (@elonmusk) February 22, 2018
Apart from this, Musk also tweeted that they’d attempt to beam out “Hello World” when passing over Los Angeles, California.
So How Exactly Does Starlink Work?
Satellite communications primarily operate using large satellites in a geosynchronous orbit around 35,000 km above the Earth. Due to this distance, it takes time for signals to travel between the Earth’s surface and the satellite, often resulting in a lag.
In order to combat this, Starlink’s satellites will operate at a much lower orbit, known as Very Low Earth Orbit or VLEO that is less than 2,000 km from the Earth’s surface. Tintin A and Tintin B will be in orbit at a distance of 625 km from the Earth’s surface.
The constellation aims to use the sparsely used V-band to communicate. This band is the part of the electromagnetic spectrum that operates between 40 and 75 gigahertz (GHz). Due to its lack of use, the V-band is being looked at as a potential medium for high-end broadband coverage. It is currently in use by the United States’ Military Strategic and Tactical Relay (Milstar) constellation of communications satellites, mainly to provide communications for the US Armed Forces, particularly in the 60 GHz range due to its high data rates and protection against interception because it lies in a strong absorption band.
Due to the low orbit of the satellites, latency and time lag is expected to reduce, while at the same time, the V-band will enable higher data transmission.
SpaceX intends to extend the Starlink constellation to Mars as well as part of their larger goals of getting humans to Mars. It also plans to sell satellites to use the Starlink satellite bus for research and exploration.
So What Happens When A Satellite Has Outlived Its Life?
The estimated life of each satellite is approximately five to seven years. Once the satellite reaches the end of its life, it will be shifted to a disposal orbit by propulsion from where it will re-enter the Earth’s atmosphere around a year after it completes its mission.
All of them will be launched using SpaceX’s Falcon 9 rockets. However, if a limited number of satellites are to be launched, wouldn’t it make more sense to use a smaller rocket?
The first rocket in the Falcon family, the Falcon 1 was a small rocket that was retired in 2009 after its first successful commercial launch. It was eventually replaced by the Falcon 1e, which has never seen a commercial launch till date.
And if only one satellite were to be launched? Perhaps the Japanese Aerospace Exploration Agency (JAXA) had launched its SS-550 earlier this month. Pegged to be the world’s smallest rocket, its payload was a 13.6 inch long CubeSat. JAXA, however isn’t the only one developing smaller rockets. Private players such as Rocket Labs too have launched small rockets for smaller payloads.
Smaller launch vehicles make it easier and cheaper to put individual and a handful of satellites into orbit, just what a constellation of small satellites would need in case anything in the constellation ever went down.
Starlink’s satellites are not designed to have a fixed position in orbit and will keep moving around in synchronisation. Musk aims to have 40 million subscribers to the service by 2025, generating around $30 billion in total revenue.
The last such attempt to provide broadband using devices in the atmosphere was Project Loon, a spin-off of Google X which aimed to use high-altitude balloons in the lower stratosphere (18 km) to create a “floating” wireless network. However, the sheer scale of the project meant that it couldn’t take off the way it was intended, quite literally.
Starlink will certainly fare better since it will see reduced atmospheric disruptions such as bad weather or pressure changes in the atmosphere. The constellation aims to go live by 2019 and the sector is currently seeing significant competition.
The Benefits
The benefits of having a communications satellite constellation are vast. It would mean better broadband penetration in rural and semi-rural areas, where terrestrial connectivity has not been able to travel.
Given the emphasis on a digital lifestyle with many countries going in for a cashless economy, who doesn’t want more internet?
Starlink will certainly go a long way in development of the Internet of Things (IoT) that relies on having a good steady internet connection. Arguably, the biggest beneficiary of this would be Musk’s Tesla Motors. The Tesla Model S allows drivers to unlock their car sans key using the internet. One such user, however got locked out of the car because of poor connectivity in the area. Such occurrences may soon be a thing of the past if the Tintin family’s 12,000 satellites are placed into outer space.
Also Read: Harnessing Solar Power From Where There Is No Night — Space
Srikanth’s interests include public transit, urban management and transportation infrastructure.