Operational Domains of the Space Economy
The space economy is a growing sector, with increasing interest and investment from private companies, governments, and research institutions. This growth has led to the development of new technologies and infrastructure, pushing the boundaries of what is possible in space. Understanding the operational domains in the space economy is crucial to comprehending the breadth of opportunities and challenges that lie ahead.
This article outlines and explains the following operational domains: terrestrial, suborbital, Low Earth Orbit (LEO), Medium Earth Orbit (MEO), Geostationary Earth Orbit (GEO), Cislunar, lunar, and deep space.
The terrestrial domain refers to Earth-based infrastructure and systems that support space operations. These include launch facilities, ground stations for satellite communication and tracking, research and development centers, and manufacturing facilities. Terrestrial operations are critical for the success of all space-based activities, as they enable the launch, control, and monitoring of space assets.
Suborbital space lies just above Earth's atmosphere but below the altitude required for a stable orbit. Spacecraft in this domain follow a parabolic trajectory, briefly experiencing microgravity before returning to Earth. Suborbital flights are used for scientific research, technology testing, and even space tourism, as demonstrated by companies like Blue Origin and Virgin Galactic.
Where does space start?
There is no universally accepted definition of where space starts, as the Earth's atmosphere gradually thins out and transitions into outer space without a precise boundary. However, the Kármán line is a commonly used reference point to define the boundary between Earth's atmosphere and outer space. The Kármán line is located at an altitude of approximately 100 kilometers (62 miles) above Earth's mean sea level. It is named after Hungarian-American engineer and physicist Theodore von Kármán, who calculated that at this altitude, the atmosphere is too thin for conventional aircraft to generate lift, and vehicles would need to travel at orbital velocities to maintain flight.
Low Earth Orbit (LEO)
LEO ranges from approximately 160 to 2,000 kilometers above Earth's surface. This domain is popular for satellite operations due to its proximity to Earth, which allows for better communication and higher resolution imaging. LEO is home to the International Space Station (ISS) and numerous Earth observation, communication, and scientific satellites. It is also the orbit for broadband satellite constellations like Starlink and OneWeb, which are aiming to provide global internet coverage. However, the increasing number of satellites in LEO has raised concerns about space debris and the need for sustainable practices in space.
Medium Earth Orbit (MEO)
MEO, situated between 2,000 and 35,786 kilometers above Earth, is primarily used for navigation and communication satellites. The Global Positioning System (GPS) operated by the United States, Galileo by the European Union, and other regional navigation systems reside in this domain. MEO satellites benefit from a wider coverage area than LEO satellites while maintaining relatively low signal latency.
Geostationary Earth Orbit (GEO)
At an altitude of approximately 36,000 kilometers, GEO satellites orbit Earth at the same speed as the planet's rotation, effectively remaining stationary relative to a specific location on the surface. This unique characteristic makes GEO ideal for communication, meteorological, and Earth observation satellites. However, the higher altitude increases signal latency and requires more powerful transmitters and larger antennas for communication.
Cislunar space encompasses the region between Earth and the Moon, including all orbital paths around both celestial bodies. This domain has gained significant interest as a staging ground for lunar and deep space missions. It is also the target for future space infrastructure projects like lunar orbital platforms and the Lunar Gateway, which will serve as a research outpost and refueling station for spacecraft.
The lunar surface is the destination for numerous upcoming missions, driven by scientific curiosity, resource utilization, and human settlement aspirations. The Moon offers a wealth of resources, such as water ice and rare earth elements, which could be used for life support and in-situ manufacturing. Establishing a human presence on the Moon would provide invaluable experience for future deep space missions and the development of a sustainable space economy. Several countries and private companies have announced plans for lunar landers, rovers, and habitats in the coming years, setting the stage for a new era of lunar exploration and development.
Deep space refers to the vast expanse beyond Earth and lunar orbits, including other planets, asteroids, and the interstellar medium. Deep space missions, such as robotic probes to Mars, Jupiter, and Saturn, as well as asteroid mining ventures, are expected to play a crucial role in expanding our knowledge of the cosmos and harnessing resources for future space endeavors. The successful exploration of deep space will require the development of advanced propulsion systems, radiation shielding, and autonomous navigation technologies.
The operational domains of the space economy, ranging from terrestrial facilities to the depths of deep space, offer a myriad of opportunities for scientific discovery, technological innovation, and economic growth.