In 2017, India launched a record 104 satellites into space. Barring one, the rest of the satellites that were launched were small satellites.
By Nandini Sarma
In 2017, India launched a record 104 satellites into space. Barring one, the rest of the satellites that were launched were small satellites. Small satellites are miniaturised satellites that weigh under 500 kilograms. Evolution of the technology for building small satellites is making it accessible to a wide range of users, from university students to engineers and scientists all over the world. Small satellites have several advantages over large satellites namely cost effective ways to test newer technologies, opportunities for local industry, bigger basket of potential users and thus a large variety of mission possibilities. Further, the number of countries that are pursuing their own space programmes has grown over the years. Financing the space programmes for these emerging players is quite a challenge, but small satellites offer a possible solution.
Small satellites are transforming the dynamics and economics of space industry. Small satellites ensure that space technology is no longer monopolised by nations with well-funded programs that build large and expensive satellites but is accessible to smaller and newer entities. It appears that commercial entities even find economic incentives in pursuing the small satellites route. The global market for small satellites is estimated to be worth US$7.53 billion by 2022. In keeping with the growing trend, ISRO is developing a Small Satellite Launch Vehicle (SSLV) that will exclusively be used to launch small satellites and thus offer affordable launch options and boost revenues.
Small satellite constellations are emerging as a powerful and effective tool for various applications. One of the important application is the ability to provide internet from space. Currently, internet services are provided by large satellites in geo-synchronous or geostationary orbits. However, due to the long distances, there is latency in the internet services i.e. the time between satellites receiving a signal and response time. This is an issue for real-time usage such as video conferencing; financial transactions. Satellites in low-earth orbits (LEOs) can reduce the latency time interval. Further, it would help internet to reach areas where cable internet is not possible. This possibility has led to a race between companies such as Space-X and One Web to build constellations that would provide internet to the whole world and compete with traditional forms of servicing internet such as cellular data and cable internet. However, given their small size, it also means they cover a much smaller area and hence requiring the need for a large number of such satellites. Another application where constellation of small satellites can be used is earth observation. By providing continuity in coverage with frequent revisits, they can introduce a new phase in the era of sustainable Earth observation.
While the future of small satellites seems promising, space suffers from the tragedy of the commons. Currently, there are about 1,957 spacecrafts orbiting the Earth. To put things in perspective, the average speed of satellites in LEO is about 28,000 kilometres per hour. At such speeds, if objects collide against each other, it would lead to them breaking up into many smaller pieces. This, in theory, could lead to a possible Kessler syndrome where if the density of objects in LEO is high enough then possible collisions could lead to a cascading effect where space debris formed by the initial collisions leads to a catastrophic chain of more such collisions. This would lead to a mass of millions of pieces that could make the orbital plane non-functional as well as prevent access to other orbits. The advent of mega constellations has the potential to create such a situation. As discussed, many companies have proposed tele-communications constellations consisting of hundreds and thousands of small satellites. In February 2019, One Web launched six satellites, out of a planned constellation of more than 650 satellites. It was launched in French Guiana by Arianespace. It plans to provide full internet services anywhere in the world by 2021.
Even though the prospects of world-wide internet sounds exciting, there are concerns. Space debris is making aerospace companies concerned about the possible implications. In addition, this would mean that there is a need to safeguard against such collisions; it would imply that satellites would have to be built in a way that they can withstand a certain level of damage from possible collisions. This, however, would increase the time and money spent on producing probes. In a recent report by NASA, it has recommended that companies make sure their future satellites are taken out of orbit as soon as they complete their missions. But, many small satellites lack a propulsion system that would allow them to manoeuvre themselves to de-orbit. There are different technological solutions that are available to help de-orbit defunct satellites or those that have completed their missions. In addition to this, nations have to device mechanisms to track space debris and enhance their space situational awareness.
The diverse range of stakeholders in the space industry today means that norms and rules need to be developed beyond just states as stakeholders. The most central issue that needs to be addressed is building consensus among key powers in addressing issues that challenge the long-term sustainability of outer space. Financing is another factor that is important. A global regime to deal with this issue is urgently needed in order for space to be used sustainably in the near future. While there are different measures being contemplated within the United Nations Committee on the Peaceful Uses of Outer Space (UNCOPUOS) and Conference on Disarmament (CD), sustainability of outer space has to be at the centre of these debates and developing a global agenda in this regard should remain a key focus especially in the context of small satellites becoming part of the global trends.