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Small Satellites Go Back to the Future

A renewed interest in launch rideshares for small satellites is enabling more frequent opportunities to reach orbit at a competitive price. We look at who’s involved and what’s next for the industry.

Image courtesy NASA/Ames Research Center

Generally, rockets go to space to place satellites with a payload, like a camera or radio, for observation or communication. Around they year 2000, it became increasingly easy to make small, inexpensive satellites to rideshare into space as part of a larger satellite launch.

Companies were dreaming of constellations of these smallsats, but the destination orbit was generally off. The market responded by producing destination-specific rides on smaller launchers. Eventually, new and better onboard thrusters and space tug capabilities made repositioning a satellite in space a real option. These advances have led to renewed interest in ridesharing — companies offering more frequent launches to the right orbit at a good price.

So, who’s involved in the small satellite market? What does it mean for other industry players? What’s next for small satellites?

Dedicated Launch Providers

As small payloads have matured into operational commercial and government systems, the ability to launch into specific orbits on schedule has facilitated a more competitive launch market. Companies now offer destination flights for small payloads, and there is growing interest in privately owned launchpads, air-launched systems, and mobile and stationary launch platforms designed to support the custom small launch market. Small launch providers are now a a market segment. Fueled by dedicated launch demand and ready venture capital funding, there are currently over 148 different small dedicated launchers in development worldwide.

Launcher One. Photo courtesy Virgin Orbit.

Virgin Orbit uses a rocket launched from a Boeing 747 to deploy smallsats into space. This Virgin Group company, based in Long Beach, California, was formed in 2017. On January 17, 2021, Virgin Orbit launched their air-launched rocket LauncherOne, which reached low Earth orbit and deployed 10 cubesats for NASA, among other payloads.

Through its subsidiary VOX Space, Virgin has been awarded a $35 million contract for three launches of 44 cubesats for the United States Space Force. The first operational mission of LauncherOne delivered seven cubesats to orbit in June of 2021. Virgin Orbit is one of the companies selected by the Brazilian Space Agency to launch from the Alcantara Launch Center in Brazil. Virgin Orbit also has plans to launch space flights from Spaceport Cornwall in partnership with the U.K. Space Agency.

Rocket Lab, headquartered in Long Beach, California operates a small orbital rocket, called Electron, for dedicated launches of small satellites. The company has successfully launched more than 100 smallsats for government and commercial customers, and is developing a booster reusability technology. In August 2021, Rocket Lab went public via a special purpose acquisition company (SPAC).

Enter the Space Tugs

Space tug technology is gaining real-world credibility and could be a significant factor in reshaping the smallsat rideshare market. Space tugs provide last-mile “taxi” services — placing small cargos in preferred custom orbits. Depending on the mission, there can be a cost advantage for small cargos to ride on large launchers.

Northrop Grumman kicked off the “age of tugs” in 2020 with their landmark in-orbit servicing achievements. The company’s Mission Extension Vehicle-1 (MEV-1) lifted the Intelsat IS-901 satellite out of the GEO graveyard orbit and placed it back into service. In April 2021, the Mission Extension Vehicle-2 (MEV-2) docked with Intelsat’s 10–02 spacecraft to extend its life.

Seattle-based Spaceflight deployed 15 spacecraft in the debut flight of the Sherpa-FX space tug in January 2021. The company launched two Sherpa tugs on the SpaceX Transporter-2 mission in June 2021, one of which had electric propulsion from atomic fusion. Spaceflight expects to fly their next generation Sherpa-LTC on a different SpaceX mission later this year. Each Sherpa can be stacked and launched with other Sherpa modules for later separation and independent free-flying.

The SpaceX Transporter-2 mission launched two Spaceflight Sherpa tugs in June 2021. Photo courtesy SpaceX.

Italy’s D-Orbit demonstrated the world’s first commercial last-mile delivery service in October 2020, using its In-Orbit Now (ION) vehicle to deliver 12 Planet SuperDove satellites to orbit. It is working on space debris solutions as part of its future development.

Exolaunch is a German company brokering rideshare missions. It plans to conduct flight tests for its Reliant tugs next year. In 2023, Exolaunch plans to flight test a Reliant Pro configuration that can make finer adjustments to custom orbits post-launch, such as a satellite’s orbit inclination. It is also working on space debris solutions and is expected to compete with D-Orbit in this trade space in the future.

Momentus is a commercial company that provides last-mile, in-space delivery for small satellites with what is claimed to be a novel, water-based propulsion system. Their family of space tugs move satellites dropped off at a common orbit to custom, highly precise orbits for specific space-based applications. The company has experienced recent turbulence in their technology and their public offering through a SPAC, and the outlook appears to be cloudy.

One creative advance in space tug technology is the use of ESPA rings with an added propulsive capability. The United States Space Force is developing a rapid launch capability for small satellites and hosted payloads using an ESPA ring equipped with just such a power and propulsion system. The Space Test Program 3 mission, launched in December 2021, carried the first Long Duration Propulsive ESPA (LDPE) payload.

The EELV Secondary Payload Adapter (ESPA) used will be Northrop Grumman’s ESPAStar bus, equipped to carry payloads to final orbit after launch. Three LDPE missions will be launched in the next 18 months, and then the capability will transition to a program called Rapid On-orbit Space Technology Evaluation Ring (ROOSTER). Two contracts will be awarded for ROOSTER missions in the near future.

Moog has developed the Orbital Maneuvering Vehicle (OMV), a propulsive tug for secondary payload deployment based upon the Moog NSSL EELV Secondary Payload Adapter (EPSA) ring. The OMV can be used to disperse and position small satellite constellations, act as a hosted payload platform, or deliver a single spacecraft to its ideal orbit.

Starfish Space, a Washington-based company, was founded in 2019 to launch an all-electric tug called Otter by 2023. Otter is a smaller tug than its competitors. This allows Starfish to operate a network of the tugs in space, providing on-demand satellite servicing.

Tokyo-based Astroscale intends to demonstrate capabilities required for debris removal, including client search, inspection, and both tumbling and non-tumbling rendezvous docking.

Back to the Future — Rideshare and Beyond

In 2017, India’s Polar Satellite Launch Vehicle (PSLV) record-breaking launch of 104 smallsats may have helped reinvigorate rideshare, but three combined factors will enable the long-term market. These include the growing market for smallsat launch, increased launch frequency, and the tugs that can deliver the needed orbit accuracy.

The at-scale performance and cost of in-space tugs remains to be seen. If successful it will, at minimum, slow the growth of small launch business as cost-conscious, less time-sensitive small-payloads opt for rideshare. In January 2021, SpaceX’s Transporter-1 rideshare mission released 143 satellites breaking the PSLV record, followed up by a second dedicated rideshare in June that released another 88 satellites. The SpaceX rideshare program could put downward pressure on prices for small satellite launches generally.

Tugs alone cannot account for this trend, but given the foundational technology on which they are built, we may see growth for tugs in adjacent areas, such as in on-orbit servicing, assembly, and eventually on-orbit manufacturing, as well as more exploratory missions in cislunar space, to and around the moon, and beyond. The recent run of space SPACs attests to considerable excitement in the space domain beyond space tourism. What remains to be seen is whether these are solid bets.

State of Play is a bimonthly advisory publication dedicated to emerging trends in space innovation in the private sector. View online at



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