How is Space Technology Different?

by Bruce Elbert, President, Application Technology Strategy, Inc.

Austin, Tex., August 15, 2024--Space may be the final frontier, but the principles of its exploitation have not changed since Russia and the US launched the first artificial satellites before 1960. Our best approach is to view space as a complex technical domain where objects made by humans are launched in earth orbit (and potentially beyond) by vehicles that burn chemical fuel to coexist with an environment very different from what we find on our planet (or any other planet for that matter).

Like airplanes that wing their way in our atmosphere or submarines that travel under the seas, spacecraft are constructed to survive and operate in the inhospitable environment of space. Lastly, those spacecraft are designed and manufactured for a specific purpose (e.g., communications, earth observation, navigation, security and protection, etc.) and have features (functionality and specifications) that are readily understood and verifiable before launch; all must be proven out for that space environment before launch lest they fail in their respective missions. It makes no sense to place an airplane or submarine in space, likewise for a spacecraft in flight or submersed in the sea. Having such a platform at a distance from earth affords excellent coverage for communications at radio frequency, laser link potential, and ability to observe the earth. The trend in radio signal usage follows the increasing range of the spectrum and today at millimeter wavelengths. Therefore, space technology combines with modern ground-based resources that give us more capability and potential for human progress.

Long-term Trends in Space Technology

Past decades have seen extensive development of the use of earth orbit for communications, earth observation, navigation science, and delivery beyond. This is primarily unmanned, at least commercially, but the government sector has supported manned space particularly for the space station. The orbits employed were primarily GEO and LEO with a lot of solid experience with very good performance in terms of useful payloads in orbit that meet demands. Leading commercial operators like Intelsat, SES, Eutelsat, JSAT and Telesat grew and new entrants like DIRECTV, DISH, Iridium, Arabsat and Viasat expanded market opportunities. The launch services side of the industry changed little over this period, with US rockets like the Delta, Atlas and Titan carrying the bulk of the mass to orbit, but Europe built up Ariane to the point of near dominance after loss of the Space Shuttle.

Image courtesy of ESA

As a vehicle designed to operate in vacuum without much in the way of external forces (other than gravity), a spacecraft will always be composed of certain elements. These are the electrical power system, the propulsion system, a control system to maintain its orientation and flight path, and a structural system that contains and protects these systems from radiation, heat and cold, and low levels of bombardment. Taken together, this is the spacecraft bus that carries and supports the payload that provides the business end of the overall vehicle. Communications payloads will contain analog components that produce the most power and bandwidth, and digital processors are available to add dynamic beam forming and other forms of flexibility.

The approach is to design a spacecraft for the particular purpose, choose proven components and assembly techniques, and to extend beyond this base only if absolutely necessary for a particular application. The 1980s, 1990s and through around 2010 were decades of incremental innovation and increasing investment to exploit markets and remain competitive among the companies that built and operated space systems for earthly use. Major aerospace companies like Boeing (né Hughes Aircraft), Lockheed Martin, Northrup Grumman, Loral, Airbus and Thales Alenia dominated the industry and appeared to hold onto all major projects and supply chains. This approach minimized risk but it is claimed that it held us back in terms of applying more scale and innovation in space technology.

The methodologies of space technology development are based on attention to detail, because literally any component or association of components can cause poor performance or failure of part or all of a space system. This emphasis starts with the architecture of the system and its ability to address the specific need or needs, and then proceeds through a detailed design process which emphasizes performance, reliability, cost and time to market. The components need to be proven well before they are incorporated, including testing in simulated space environment and demonstration of lifetime sufficient to satisfy the mission. GEO satellites are central points in the system and were well understood by all participants. But going to a LEO system crossed a Rubicon in the sense that whole batches of identical satellites would be produced and launched at reduced cost per satellite. Motorola’s Iridium constellation, originally launched in 1998, experienced a high degree of early failures due to the non-redundant design as well as the accelerated test program on the ground. They caught themselves early and increased testing to eliminate infant mortality.

If the mission involves humans in space, then normal care and validation increases substantially to what Elon Musk described as a “ridiculous amount of testing” before launch. His use of the word “ridiculous” is actually to the point as it was the British interpretation, meaning “a whole lot”. Often ignored until later is the approach to the ground segment needed to establish and operate the space segment and to provide communications, observation, or other services to the user community. The criticality of space technology is matched by the proper positioning and management of the ground segment.

All of this said, space technology is dependent on the careful application of proven processes, materials, and systems. Launching spacecraft from earth, controlling them in spaceflight, delivering applications or even people, still demand this type of care and attention to detail. Launching more vehicles does not overcome the known challenges of the space environment; it may reduce the criticality of individual elements if the overall system offers diversity sufficient to the purpose. Computers and software began to play a key role through the design of critical elements like antennas and control systems, as well as innovation by Hewlett Packard to automate in the factory testing and calibration, and finally on orbit to simplify operations using canned procedures and improved graphical displays. Spacecraft were hand made by experienced technicians, typically one at a time. Then, partly completed subsystems and final assembly required manual transfer from one area to another. But the innovation of the true assembly line and the use of robots would have to wait until the principles of automobile manufacture (read Tesla) were transferred to the spacecraft factory (à la Starlink).

What Changed Around 2015

They called it “New Space” or “Space 2.0” in remembrance of the year 2000 Internet “dot com” boom. The New Space paradigm became all the buzz when Silicon Valley recognized startups like SpaceX and Rocket Lab which challenged the assumption that launches were the domain of NASA, the DoD and the largest commercial satellite operators. Its cult nature is shown in the hope for, “Services that Could End World Problems[i].” Hundreds of VC-funded startups appeared with interesting concepts like Internet of Things (IoT), Direct to Device (D2D) for service to cellphones, cheap rockets to launch small payloads, and manufacturing in space (an old concept tried by NASA over 20 years ago). Interest in space travel for leisure and the return to the Moon as well as flight to Mars became the rage. But the most successful New Space startup to date has to be the StarLink LEO broadband constellation from SpaceX. Amazon’s founder, Jeff Bezos, picked up on the SpaceX Starlink theme and is in the process of creating his own broadband LEO enterprise named Kuiper.

SpaceX did some things differently in their innovative reusable boosters and mass production of small LEO spacecraft. They are also the first to put optical intersatellite links into commercial use for trans-oceanic data transfer. As innovative and inventive as SpaceX is, they follow many traditional approaches of employing space technology in a practical scheme to perform earthly functions. The first satellites were also in LEO having been placed there with similar chemical rockets and employing line-of-sight communication by electromagnetic means.

Spacecraft have journeyed far outside of earth orbit as far back as 1962. Mariner 2 became the first successful mission to another planet when it flew by Venus on December 14[ii]. And Surveyor 1 (May 30, 1966), was the first of a series of seven robotic spacecraft sent to the moon to gather data in preparation for NASA's Apollo missions. It was the first spacecraft to make a true soft landing on the moon[iii]. In those days, critical calculations were performed using slide rules rather than advanced computer systems. Of course, today we have the cloud and AI to optimize everything about the space vehicle and its mission. But, the hardware is not substantially different and must undergo the same detailed process of design and test.

I suggest that people involved in New Space on the one hand and the classical development of big systems on the other will still look at things in much the same way as space technology pioneers of the 1960s and 1970s. We have digital tools that we could only imagine 20 years ago, and they afford things in the factory, launch pad, and in space once vehicles are in motion. Also, the ground segment is much more adaptable and functional to exploit the Internet in all its forms, including Software Define Wide Area Networks (SD-WAN) and AI. The software schemes are now much improved with digital twins of the entire spacecraft before it is constructed; digital twins are extended through the operation of the entire constellation, network or complex deep space mission. One still needs a clear vision of what is intended, an architecture that makes sense both now and in the future, and solid engineering processes straight through development and start of service.

Success in the Next Decade

Success depends on innovation as we see SpaceX and Rocket Lab accomplished. One of their more interesting and rather incredible innovations was booking a launch on the Internet. The legacy method was to engage in a very lengthy and involved interface and integration process where the launch provider and buyer gain sufficient understanding of each other. The new players deliver so many launches at rather reasonable prices and so cannot afford traditional courting. You design to their interface and they put your spacecraft in the desired trajectory or orbit.

Today’s software tools and launching systems are so much better than what was available in years past. That combined with the will to pursue useful goals will continue to allow space technology to be a force for prosperity on earth. The sky was the limit; now, space is an active part of our future as long as future generations of practitioners follow the rules learned over the past 60 years. Innovation is a constant in space technology because we are dealing with the complex interaction of physical objects with numerous subsystems that are under control of networks of ground and other space facilities. A relatively small improvement in capability, such as electric propulsion and real-time assessment of link performance, brings with it more in the way of service potential and reduced cost and risk.

What I would like to see from here is better definition of what the actual use will be of a given space solution, how much it will cost, and how it will operate in coming years. We cannot afford experiences like the original Iridium LEO constellation which went bankrupt after only one or two years of operation. The tools exist today to understand what and how, but the bigger issue is why are we employing space technology and how will it perform. Engineers and scientists are great at the how, but the vision needs to be clear and definite. Its interesting that successes like GPSS, DIRECTV and Starlink have in common the right backing and vision of application. These give me confidence in where space technology will shine brightly in the future. Does today’s Tesla bare any resemblance to Henry Ford’s Model T? It still has four wheels, a drive train and steering wheel, seating and a power plant (all be it electric motors versus a combustion engine). Hey, I learned about both in my engineering courses back in the early 60s. I also learned to program a computer (a very big and slow one, by today’s standards). Nothing new under the sun – only what humans can do with space technology from our earthly perspective, imagination and resolve.

Manufacturing of large constellations is highly industrial, relying more on vertical integration of the enterprise than employing components produced by others. Single spacecraft manufacture could be accomplished in the past like house construction, but even here improved design, test and verification processes can reduce cost and improve product reliability. More functions and better calibration bode well for commercial as well as scientific missions into space. Advancing the state of the art of RF and optical power generation and signal processing, coupled with intelligent overall network operation, likely will continue to improve the delivery of network services from space and reward those who practice this well.

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Bruce Elbert is the Founder and President of Application Strategy LLC.  He is a satellite industry expert, communications engineer, project leader and consultant with over 50 years experience in communications and  space-based systems in the public and private sectors. Areas of expertise include space segment design and operation in all orbit domains, systems architecture and engineering, ground segment systems engineering, development and operation, overall system performance improvement, and organizational development. He has been an expert witness in legal proceedings related to radio communication system performance, patents, construction contracts, service agreements, RFI identification and resolution, and taxation. He can be reached at: bruce@applicationstrategy.com