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Spazio 2050 n. 6 - Smallsat Revolution - English

Smallsat, the revolution of the small

by Emilio Cozzi

On June 17th, 1946, in Saint Louis, a man picked up the phone and history answered: he was in his car, and that call would be the frst one from a mobile device.

In 2021, 75 years later, a few newspapers commemorated the event by highlighting a vintage curiosity: that phone, tested by Southwestern Bell, one of AT&T’s local companies, “took up much of the space of the boot” and “weighed 80 pounds”, about 36 kilograms. In other words, to be a stricto sensu portable device, it needed a car to make it mobile Mutatis mutandis, something similar is happening in the feld of technology designed to operate beyond the terrestrial atmosphere.

The frst satellite built and launched by man, the Soviet Sputnik, weighed 83 kilos: we would now call it a “nanosatellite”, from the SmallSat family, tools whose mass is lower than six quintals.

However, except from this historical record, the Sputnik had very few functions: sending a radio signal, listened to also by radio amateurs all over the world, and scare Americans to death.

In the six subsequent decades, the orbited satellites were like the mobile phone in Saint Louis: big, heavy and expensive, and they required a transport vehicle, a partly exclusive launcher (chosen to meet their needs), to move. However, same as in mobile telephony, a few giant steps have been made in the feld of aerospace technology, which have allowed to return to the limited size of the frst Sputnik and excessively expand his capacity and utility. It’s a process which is capable of radically changing the strategies of a few business sectors.

An image of Verrazzano bridge in New York, taken by Cosmo-SkyMed. Credits: Asi

According to an analysis by Bryce Tech on the decade between 2012 and 2021, over 4.600 out of the 5.681 satellites launched in space, that is 82%, are Smallsats. In 2021, small satellites accounted for 94%, that is 43% of the overall mass sent beyond the sky. The boom, in the last two years, is due to the Starlink and OneWeb mega-constellations for broadband Internet, which together have seen the departure of over 2.000 units. Smaller, cheaper and more numerous, same as smartphones.

Space agencies are moving in the same direction: the Nasa, for example, will take Smallsats around the Moon. The Italian Space Agency will soon launch new satellite programs born around the same concept, of course, without abandoning the path followed so far with large devices. Actually, it will be an integration of the big with the small, whereas the second one is the result of the research conducted to develop and build “heavy” and highly-performing tools such as Cosmo-SkyMed and Prisma: state-of-the-art knowledge and know-how

PLATiNO 1 (SAR) in orbit over Italy (rendering) Credits: Asi

in Earth observation technologies. The way was paved by the Plati no (High-technology space platform) program, the promise of a new extra-atmospheric paradigm: it’s a standard and customizable structure, capable of hosting diferent tools for equally diferent purposes.

The second one, Iride, was “baptized” last May by Samantha Cristo foretti, during a live session from the International Space Station. The constellation will be made up of dozens of Smallsats with diferent si zes: a feet with groups of satellites designed to measure specifc aspects, from the quality of water to the movements of soil. These will be joined by the feet of Alcor CubeSats, about which we will talk in the article in the next few pages.

Platino is a “jolly ”. It means that the same model of vehicle, a satel lite, can be equipped with diferent tools according to the required features: Earth observation, telecommunications, scientifc fndings. Funded by the Asi and the government with 100 million euros, Platino will be manufactured by a temporary group of companies, made up of the ofcial supplier Sitael with Thales Alenia Space, Leonardo and Airbus Defence and Space. Still in the Smallsats class, it will use smal ler tools, satellites weighing about 200 kilograms: «Starting from 2017 – recalls Francesco Longo, head of Earth Observation unit of the Italian Space Agency – we developed this multi-mission platform, designed to have the right fexibility and carry several tools. The goal is increasing performance and reducing size». In other words, ofering the “model” of a spacecraft – a car which carries a phone, still talking about Saint Louis -: a small one, but with an increasingly important performance, which can be integrated with that of bigger and more expensive satellites. This in-tandem operation approach has no equivalent as of today. An example of this will be Platino 1: it will take of by 2023, it will be equipped with a synthetic aperture radar (SAR) tool in the X-ray band – a technology where Italy has been standing out for years – and will operate with Cosmo-SkyMed, for example to measure the movements of soil: volcanoes, landslides on mountainsides, but also bridges and buildings. «They will work with what, in jargon, is named a bistatic confguration: Cosmo-SkyMed, like a radar, is an illuminator and sends and receives a signal (electromagnetic emissions in radio frequency, editor’s note). Likewise, Platino will be capable of both sending and receiving, but also of observing the energy refected by Cosmo-SkyMed. It’s like it is observing the same scene from another point of view, and this will signifcantly increase the information contained in each image. It will be undoubtedly useful, for example, to the Civil Protection department». Developed with the Nasa, the Platino 2 mission will instead carry a tool in the infrared, designed to measure the quality of air, particulate matter and fne dust. Its current name is Maia (Multi-Angle Imager for Aerosols) and is expected to take of in 2024: «It will be an extraordinary, citizen-oriented mission – observes the Asi engineer -, which isn’t just targeted at biochemical knowledge, but will also be in partnership with healthcare communities. It is not by chance that Arpa Emilia Romagna is part of our advisory group and scientifc community. Platino 2 is designed to observe critical areas such as Taranto, Gela, the Po Valley, and cross the information on particulate matter with statistics on respiratory diseases».

Platino 3 will take a road less travelled as regards the Italian sensor technology, that high-resolution optical cameras, where France is currently holding a leadership position (just think of the pair of Pleiades satellites). Equipped with a hawk’s sight, Platino 3 will boast a half-a-meter ground resolution.

Finally, Platino 4 will enhance the “superpowers” of another national excellence, the Prisma (Hyperspectral Precursor of the Application Mis-

is an illuminator, and sends and receives a signal

An image of Chongqing, China taken by Cosmo-SkyMed. Credits: Asi

sion), which monitors the planet’s health by observing the chemical form of the elements it is made up of: “In this case, it’s not the 30-meter space resolution which is interesting, but the spectral one. Prisma works on 240 bands and provides 240 images for each part of Earth it observes. This allows to understand the biochemical characteristics of matter. The second-generation Prisma will have a 10-meter spatial resolution, which no one has. Platino 4 will add its multispectral, slightly lower performance, which however is obtained thanks to a satellite weighing just 250 kilograms. One day we may think of launching fve or six of them and have an on-demand observation capacity, when and where necessary, thanks to a revisit time of just a few hours».

The “revisit time” is the time it takes for a satellite to look at the same location again. It’s one of the strengths brought by SmallSat constellations. Today, the most well-known examples are the above-mentioned Starlink and OneWeb, infrastructures designed to guarantee a ubiquitous, broadband and low-latency Internet connection from space: by travelling in or-

bits close to Earth, and therefore at high speed, each of their units soon disappears beyond the horizon. To guarantee the continuity of service, we therefore need a closely interconnected network, made up of thousands of satellites. “We do not only need a progressive improvement of performance: this must happen by taking advantage of small objects – highlights Longo, bringing the discussion back to the topic of Italian programs -. It would be unthinkable to launch twenty Cosmo-SkyMed Second Generation satellites, but we may obtain an outstanding performance, at reduced costs, with 30 Smal. That’s why high revisit capability is a key concept for Iride».

Increasing the number of tools has a cost, but the miniaturization of components and the possibility to launch dozens of them with a single rocket have decreed the success of a new type of orbital architecture. Along with that comes the boom of the market: a report by Euroconsult estimates that, in the most recent dehave moved over 23 billion dollars at global level. Such amount is ready to increase to 84 billion dollars in the next ten years: «The peculiarity of Iride is the fact that this constellation is made up of dozens of satellites whose size is smaller than the main tools developed by Italy, such as Cosmo-SkyMed – explains Guido Levrini, project manager of Iride for the European Space Agency and, until a few months ago, head of the space segment of the Copernicus program. These satellites won’t be all identical, but will have diferent sizes: we will start from the smallest ones, weighing around 25 kilograms, and we’ll continue with the biggest ones, from the Platino program, weighing around 350 kilograms. We’ll do this because they will be equipped with sensors and tools that have a diferent complexity and nature and, subsequently, also a diferent weight».

No less important is the fact that Iride can be regarded as a result of the approach – or the philosophy - at the core of Platino: several types of satellites imply a wide range of skills, the result of the technological progress of our country which, starting from big satellites, has managed to gather sensors and calculating capacity with increasingly agile sizes.

In fact, what is self-evident with Platino is common to experiences such as that of Argotec, which has manufactured Asi’s CubeSats LiciaCube and Argomoon and brought them to fy with the Nasa in the Dart missions, pointing the Dimorphos asteroid towards the Moon in the frst planetary defence test in history, aboard Artemis I.

That’s how Iride was born: «Its missions will be single-sensors missions – continues Levrini -, synthetic

A representation of the Cosmo-SkyMed Second Generation satellites. Credits: Asi

aperture radars, hyperspectral and infrared sensors, optical payloads with two or three-meter resolution (sometimes less than one meter). Iride will range from the observation of coasts to the monitoring of atmosphere, from the quality of water and water system to the movements of soil and large infrastructures. These capabilities can translate into safety, prevention and emergency management services, or in applications to support agriculture, manage the woodland heritage and many other things».

In emergency conditions, we’ll be able to observe fooded zones to identify submerged areas, for example by using radars. Alternatively, it will be possible to identify damaged buildings a few hours after an earthquake. At the same time, the eyes of the constellation will carry out a continuous monitoring, to make sure any critical scenario is predicted, faced or at least limited as soon as possible. New sentinels, more numerous and ready, will be able to perceive the upcoming cases of collapse and subsidence: «Iride is an end-to-end program, which promises a leap in quality in the use of satellite data for those who, as of today, don’t use them in a systematic manner – continues Levrini -. An important case is that of public administration, both at a regional and at a local level. The observations will help the Carabinieri for forest, environmental and agri-food protection, who have the task of monitoring the entire Italian woodland heritage, not only fres. Still talking about coasts, it will be possible to monitor the erosion, quality of water and sediments deposited by the discharge of rivers. In the feld of agriculture, a better and more punctual satellite performance will be equivalent to applications which are relevant also in the commercial feld: just think of the so-called precision farming and the management services for the growth of crops and the exploitation of hydric resources, which is important also in the feld of agriculture».

The emphasis placed on this aspect is anything but marginal: in 2016, more than half of Smallsats operated in the feld of Earth observation, which is thriving in the age of the new space economy. Increasing the number of satellites means being able to constantly look towards what is most interesting on Earth. Having both large and small tools, and being able to combine their capacities, means being able to further improve the quality of that look and transform data, and their processing, in increasingly precious raw materials for an industry of services and applications which is constantly growing.

That’s why the public investment in the Iride program, 1.1 billion Euros from the National Recovery and Resilience Plan, has the ambition of becoming a fywheel for private initiative: «Data will be shared with investors who are ready to face business risk and provide services to the commercial sector, while also making business», concludes Levrini. And it’s indicative that the program has a tight turnaround time: Iride will have to be orbited by the end of 2025, and it will happen thanks to Vega C, another signifcant success of the Italian space ecosystem.

Platino also aims at becoming an incentive for businesses. First of all, for the satellites, which should perhaps be produced in series. It’s a relatively new approach to the industry: satellites or space environments will no longer be built from scratch, and there will be an already tested and customizable standard model, similar to a prefabricated structure, which will be then exported: «The industrial sector in charge of the manufacturing of Platino is already recording a signifcant success, and this is one of the main purposes: making sure that the required assets for monitoring are attractive on the international market», concludes Longo. Something very similar to what happened after that phone call in Saint Louis, in 1946.

An image of Panama Canal, taken by Cosmo-SkyMed. Credits: Asi

An image of the Egyptian pyramids, taken by Cosmo-SkyMed. Credits: Asi

Danubio – Black Sea, Romania, image taken by Cosmo-SkyMed. Credits: Asi