The time for India to launch small in big numbers is now, lest it gets left behind
www.firstpost.com
The Indian Space Research Organisation (ISRO) just announced that it will soon transfer its Small Satellite Launch Vehicle (SSLV) technology to the private sector that will be able to provide on-demand services to put satellites weighing up to 500 kg in a low-earth orbit. The small satellites (smallsat) have begun to augment larger systems and, in some cases, replace them. Governments and commercial customers use them for their flexibility, speed of development, resiliency, low cost, and tolerance of risk. Advances in micro-electronics have enabled small spacecraft to maintain the performance characteristics of modern spacecraft in unbelievably small packages. These spacecraft are inexpensive to build, test, and launch, and can enable large constellations of 1000-plus satellites. Large constellations will provide continuous imagery to users in defence, agriculture, weather, business intelligence, forestry, and disaster recovery. It is important to understand what constitutes smallsats, their advantages and where India is.
What are Smallsats?
The smallsat is of low mass and size, usually under 500 kg. They are further sub-classifications by mass. Smallsats are cheaper to build and use low thrust less-expensive launch vehicles. They can be mass-produced and launched in larger numbers. Smallsats in large numbers are often more useful than fewer larger satellites. They are ideal for constellations for low-data rate communications. They are useful for in-orbit inspection of larger satellites; university-related research; for testing or qualifying new hardware before using it on a more expensive spacecraft. Technical challenges of the small satellites could be a lack of sufficient power storage or room for a propulsion system. Many start-ups have come into the small satellite space.
Satellite classification by mass
Recent Smallsat Statistics
The nanosatellite and microsatellite, especially 1–50 kg segments have been growing rapidly in recent years. As per Bryce Tech, 95 per cent of spacecraft launched in 2022 were smallsats. Around 54 per cent of total up-mass was by smallsats. In 2022 Starlink and OneWeb launched 1,736 smallsats compared to 568 by all others. While 87 per cent of smallsats were in the mini and micro categories, 80 per cent of the smallsats launched in 2022 were for communications, and 10 per cent for remote sensing, and 7 per cent for technology development. 88 per cent of smallsats were owned by five operators, SpaceX (3570), Planet (529), OneWeb (504), Spire Globe (151), and Swarm Technologies (173). 74 per cent of smallsats were owned by the US, 8 per cent UK, and 6 per cent by China. India had a total of 29 and was in the 13th position by smallsat numbers. India was No.5 in pure government smallsats.
Elon Musk’s SpaceX launched 61 orbital missions in 2022, nearly doubling its previous single-year record of 31 set in 2021. 34 of SpaceX’s launches were primarily to build the Starlink mega constellation, which consists of more than 3,300 operational satellites (and counting). In 2022, the number of small satellites launched increased by around 32.2 per cent over the previous year. An estimated 18,500 smallsats are predicted to be launched between 2022 and 2031.
ISRO’s Small Satellite Launch Vehicle (SSLV)
Although smallsats have traditionally been launched as secondary payloads on larger launch vehicles, now many small satellite launch vehicles are being developed to cater for the unique orbital and launch-timing requirements of smallsats. In August 2022, ISRO launched its developmental Small Satellite Launch Vehicle SSLV-D1 to cater for the launch of smallsats up to 500 kg to Low Earth Orbit (LEO) on a ‘launch-on-demand’ basis.
In February 2023, SSLV D-2, configured with three solid stages and having a lift-off mass of 120-tonne was launched to carry EOS-07, a 153.6 kg earth observation satellite, Janus-1, a technology demonstration satellite weighing 10.2 kg belonging to ANTARIS, USA; and AzaadiSAT-2, an 8.8 kg satellite realised by Space Kidz India. India will now commercialise the SSLVs through the industry on a demand basis. There are many global and Indian private companies in the smallsat launch space.
Globally microsatellite launch vehicles are being developed to deliver 10 to 45 kg payload into a 250/450 km orbit. The aim is to drive down the launch costs of smallsats to as low as $7,000/kg. Fighter aircraft of the Su-30 MKI class could also be converted to launch smallsats from high altitudes.
CubeSat
A CubeSat is a miniaturized satellite of around 10 cm cubes, weighing less than 2 kg, and often uses commercial off-the-shelf (COTS) electronic components and structure. As of May 2023, more than 2,105 CubeSats have been launched. Typically they have been used for technology development for smallsats, Earth observation, amateur radio, and biological research. As part of the MarCO mission, two CubeSats were launched towards Mars in May 2018.
Cubesats. Image courtesy NASA
Nanosatellite and Satellite Swarm
Nanosatellite may be launched individually, or multiple in what they call a “satellite swarm”. Some designs require a larger “mother” satellite for communication with ground controllers, or for launching and docking with nanosatellites. In January 2023 there were 2,138 Nanosats. Earth-imaging with significantly increased revisit can be done at a much lower cost. Countries are working on larger spacecraft specifically designed to deliver swarms of nanosats to trajectories that are beyond Earth’s orbit for applications such as exploring distant asteroids. Several start-ups have been working to develop Nanosatellite Launch Vehicles (NLV).
ISRO Small Satellites
The Indian Mini Satellite -1 (IMS-1) bus of 100 kg class (payload 30 kg) was developed by ISRO and first mission launched in 2008. Youthsat was the second mission in 2011. IMS-2 Bus is a 400 kg class (200 kg payload). The first mission of IMS-2 (SARAL) was aboard PSLV-C37 which carried two ISRO Nano Satellites, INS-1A and INS-1B, in 2017. INS-1C was launched in 2018. Many more are being developed by the private sector.
Picosatellites
Multiple picosatellites are also expected to work together in a swarm. Picosatellites are emerging as a new alternative for do-it-yourself kit-builders. These are commercially available in the 0.1 to 1 kg range. Launch opportunities are now available for $12,000 to $18,000 for sub-1 kg picosat payloads that are approximately the size of a soda can.
Femto Satellites
These satellites are useful for radio relays. The first such was launched in 2011. A hundred Femto satellites, made of composite material, measuring 4x4x4cm, designed and developed by 1,000 students from across India were launched in February 2021 via a high-altitude scientific balloon. The satellites were equipped with sensors to study areas like ozone, cosmic rays, carbon dioxide and humidity.
Indian private technology start-ups
Many emerging private technology start-ups provide opportunities for the Indian armed services to leverage smallsats. The five Indian start-ups to watch in 2023 are Skyroot Aerospace, Pixxel, Agnikul Cosmos, Dhruva Space and Bellatrix Aerospace. There are many other players. Their work ranges from electro-optical and communications satellite systems to launch vehicle technology. Indian military leadership, government directives and authorisation have begun encouraging these space start-ups. Indian space technology unicorns will contribute to the development of their SSLVs, thereby bringing down launch costs.
Technical challenges for small small
Small satellites usually require innovative propulsion, attitude control, and communication and computation systems. Most micro/nanosats have to use electric propulsion, compressed gas, vaporizable liquids such as butane or carbon dioxide or other innovative propulsion systems that are simple, cheap and scalable. Smallsats have to use miniaturised conventional communications in UHF, VHF, S-band and X-band. Nano/micro satellites may lack the power supply or mass for large radio transponders. Innovative laser receivers, antenna arrays and satellite-to-satellite communication networks are used by them. Electronics need to be “space hardened” for vacuum, microgravity, thermal extremes, and radiation exposure.
Orbital collision safety
Orbital debris could be as small as tiny flecks of paint or bits of spacecraft metal. Large debris could be a defunct satellite. Debris larger than one centimetre can be dangerous. The “space junk” is moving at 7-8 kilometres per second, or 28,000 kilometres per hour, almost seven times faster than a bullet. If moving towards each other, the closure speed would be much higher. At those speeds, even a tiny piece of debris can cause a lot of damage. As per NASA, about 13,000 known objects are bigger than 10 centimetres in diameter. The particles between one and 10 cm in diameter are approximately 500,000. Those smaller than 1 centimetre exceeds 100 million. Some satellites do carry out risk mitigation manoeuvres to avoid a close approach with another satellite. Small satellites have fewer means for manoeuvre.
Defence applications smallsats
The smallsats are important for communications, imagery, reconnaissance and surveillance. Though increasing spacecraft density in LEO makes large constellations risky, they are operationally required. The armed forces do use secure civil constellations. Smallsat development cycles are shorter and offer “responsive capability” for military contingencies. India too is pursuing limited-area Smallsat constellations. Smallsats could meet the military’s C4ISR requirements. India’s Defence Innovation Unit facilitates interaction between the armed services and space technology start-ups. A small satellite constellation can be rapidly launched using ISRO’s SSLV.
Smallsats provide redundancy, flexibility, and survivability to military planners, in terms of numbers and capabilities. Smallsats are not easy to destroy. Smallsats are more easily replaceable at the end of life, or if destroyed by military action.
Chinese smallsat capability
China is already a far more formidable space military player. China already has a constellation of satellites as part of the Yaogan series (not smallsat), which is a network of electro-optical, imagery intelligence (IMINT), synthetic aperture radar (SAR) satellites and electronic intelligence satellites (ELINT). These satellites reportedly can visualise and direct missile attacks against fixed Indian targets, such as airbases and advanced landing grounds. The Yaogan satellites also support constant surveillance and track movements across the South China Sea, Western Pacific and Indian Ocean. China has a large number of space start-ups. China has many civilian satellites used for military purposes. China Academy of Space Technology (CAST) plant at Tianjin, can produce more than 200 satellites per year, and the China Aerospace Science and Industry Corporation (CASIC) factory in Wuhan can manufacture 240 smallsats each year.
Smallsats and Indian armed forces
Smallsats are crucial for the Indian armed forces, both as sensors and for networked operations. India needs to increase many more satellites to improve revisit rates for continuous intelligence, surveillance, reconnaissance (ISR), and communications. Space has also to be leveraged for war-fighting. Air and space operations are central to the conduct of modern warfare. IAF’s doctrine 2022 uses the unitary phrase “aerospace”. The mountainous border with China puts limitations on ground-based sensors. UAVs have limited range and coverage. The larger Indian GSAT-7 series of satellites could be vulnerable in wartime. The loss of a large satellite could seriously impair military operations. The GSAT-7A supports IAF’s AFNet and IACCS. This can be greatly bolstered with the smallsats, and add redundancy. Smallsats will increasingly meet the communications requirements of UAVs.
The armed forces need smallsats for Ka-band and Ku-band communications, and jam-resistant relays. LEO-based smallsats will also provide the armed services with greater battle-space awareness and enable more integrated operations. Even the Indian Regional Navigation Satellite System, or NavIC needs to be supplemented with smallsats in LEO. India’s SSLV can carry a 500-kg payload to LEO and a 300-kg to SSO. The wide swath of GEO satellites is inadequate for IMINT and ELINT-related tasks. LEO constellations can provide persistent ISR coverage. Smallsats could have augmented ISR capability during incidents like Galwan in Ladakh. Indian armed services also need an in-depth space architecture.
Way ahead
In coming years, constellations composed of large numbers of small, less complex, and less costly satellites are likely to become progressively more cost-effective relative to constellations made up of small numbers of large, more complex, and more expensive satellites.
On the manufacturing side, mass production of mega-constellations has begun meeting deadlines set by spectrum licensing authorities. Enabling components such as electric propulsion and deployable antennas to be tested before commercialization will provide more agility to their customers. The time for India to launch small in big numbers is now, lest it gets left behind.
The writer is Director General, Centre for Air Power Studies. Views expressed are personal. Views expressed in the above piece are personal and solely that of the author. They do not necessarily reflect Firstpost’
s views.
