In the last few years, space exploration, research, and commercialization have been somewhat transformed. These fields were once the exclusive realm of space agencies funded by superpowers’ national budgets. Now, universities and private businesses have a route to space as well: nanosatellites.
View of three cube satellites (Cubesats), or nanosatellites, shortly after deployment. Image was released by astronaut on Twitter. Image Credit: NASA
History of Nanosatellites
Nanosatellites are characterized by their size: between 1 kg and 10 kg. They have proliferated in space in recent years.
The idea to use small satellites began to formulate in the late 1990s when researchers working on aerospace engineering started developing a new concept for space exploration and commercialization that would be centered on a design-to-cost approach.
The concept became known as the “small satellite mission philosophy.” This would describe new missions with strict constraints in terms of both financial cost and schedule time that would benefit the mission overall. For example, reducing mission objectives to one simplifies all of the technical and engineering challenges for that mission.
A new generation of satellites – much smaller than conventional satellites – would become a key component of the new small satellite mission philosophy approach to space exploration and commercialization.
Today, this generation of small satellites is further subdivided into standard size categories. Picosatellites weigh less than 1 kg, nanosatellites weigh less than 10 kg, microsatellites weigh less than 100 kg, and mini-satellites weigh less than 1,000 kg.
The explosion in new, smaller space missions conducted by universities and businesses – and smaller, single-objective missions from state-sponsored space agencies – in the last few years was driven primarily by an increase in the amount of missions carried out with nanosatellites. So far, over 1,000 nanosatellites have been launched by 64 countries.
Of these nanosatellites, most were sent out of the International Space Station at an inclination of 51.6 ° while it orbited around 400 km away from Earth’s surface. The remaining nanosatellites were either released around 500 km from Earth’s surface into low Earth orbit (LEO) with an inclination of 97.5 ° or 580 km from Earth’s surface at sun-synchronous orbit (SSO) with an inclination of 97.8 °.
So far, two nanosatellites have been sent on missions to other planets. MarCO-A and MarCO-B formed part of NASA’s Mars Cube One mission to the Red Planet, forming a real-time communications link for the InSight Mars mission that landed a spacecraft on the extraterrestrial surface.
The CubeSat Standard Spread Nanosatellites Around Space
So far a total of 1,186 nanosatellites have been sent to space; 1,088 of these followed the CubeSat design standard. The CubeSat design, introduced in 1999, is a significant driver for the spread of nanosatellites in space in the last few decades.
The CubeSat design was created by Jordi Puig-Suari and Bob Twiggs, California Polytechnic State University and Stanford University professors, respectively. The pair were trying to design a satellite that could be implemented into experiments quickly enough for graduate students to include them in funding timeframes.
The design characterizes satellites measuring just 10 cm x 10 cm x 11.35 cm and weighing less than 1.33 kg. The design fits in all of the primary systems used by larger satellites, and it can be built with commercial over-the-shelf (COMS) materials and components.
Puig-Suari and Twiggs never meant for their CubeSat design to become a “standard,” technically. The design was merely intended to define the mechanical external interfaces required for a satellite of that size.
However, the extreme efficiency and simplicity of the design – and the fact that the design’s inventors and proponents have disseminated it far and wide – made the CubeSat so widely adopted as to become a de-facto standard for nanosatellites.
Nanosatellites for Education, Exploration, Commerce, and Research
In the first 14 years after CubeSat nanosatellites were introduced, most nanosatellites in space were released by research organizations. A plethora of Earth observation missions with one objective could be launched, often reducing costs by sharing rides on rockets.
Nanosatellites are sometimes launched in massive constellations that work in networks to gather large amounts of data or provide large areas of signal coverage on Earth. The first nanosatellite constellations were used to gather data for Earth observation scientists.
The CubeSat design was adopted by commercial space organizations from 2013 onward. The largest commercial nanosatellite constellation in the skies today was deployed by Planet Labs, with 355 satellites in orbit together.
CUTE: Characterizing Exoplanet Atmospheres with CubeSats
CubeSats are also widely used for education from elementary through to college levels. Arctic Astronautics, a Finnish aerospace education company, sends CubeSat satellites to students so that they can conduct their own experiments in outer space.
The company is also scheduled to send the first wooden satellite into space in 2022, using the CubeSat nanosatellite design. The WISA Woodsat mission is testing a specially coated plywood in the extreme conditions of space to find out how the material could cope in future missions out of the atmosphere.
Nanosatellites will continue to dominate space missions in years to come. Global satellite communications companies are currently preparing to deploy expansive constellations into the LEO to provide worldwide high-speed mobile internet.
While conventional satellites will always have a place in the skies, nanosatellites continue to gain favor for their simplicity, flexibility, and suitability for a wide range of limited-scope space missions.
References and Further Reading
Camps, A. (2019) Nanosatellites and Applications to Commercial and Scientific Missions. Satellites Missions and Technologies for Geosciences. Available at: https://doi.org/10.5772/intechopen.90039
Nanosats Database. (2021) Nanosats Database. [online] Available at: https://www.nanosats.eu/.
Pilkington, B. (2021). Are Wooden Satellites Advantageous? AZO Quantum. Available at: https://www.azoquantum.com/article.aspx?ArticleID=257.
---. (2021). What are Nanosatellites? AZO Nano. Available at: https://www.azonano.com/article.aspx?ArticleID=5840.
Pultarova, T. (2021). The world's first wooden satellite will launch this year. Space.com. Available at: https://www.space.com/first-wooden-satellite-will-launch-in-2021.
WISA Plywood (2021). The launch of WISA Woodsat is delayed due to frequency licensing. WISA Plywood. Available at: https://www.wisaplywood.com/news-and-stories/news/2021/10/the-launch-of-wisa-woodsat-is-delayed-due-to-frequency-licensing/