ESA Increases Mars Ambitions with Mars Transportation Infrastructure

As the European Space Agency (ESA)’s ExoMars/Rosalind Franklin Mission prepares for its 2028 launch, the agency is looking forward to future Mars science and exploration needs with an eye towards increasing European space independence. With the passage of time, infrastructure and budgets are stretched ever thinner, so innovative ideas are primed to upsend the way Mars is approached and place Europe’s planetary program in the spotlight.

LightShip is a mission and spacecraft concept wherein a large tug will carry one or more smaller “payload” spacecraft to Mars orbit and release them, before moving itself to a different orbit to act as a long-term infrastructure station.

It is named after “Lightships”, or boats sent to dangerous or remote seas and oceans to act as navigational beacons in lieu of lighthouses. The first wireless distress signal in history was sent in March of 1899 by the East Goodwin lightship using Marconi’s wireless radio technology. The infrastructure side of the LightShip initiative focuses on communications and navigation at Mars, calling back to the significance of the historical Lightships as it attempts to create the first permanent dedicated infrastructure system at another planet.

The intent of LightShip is to enable low-cost Mars science missions while building up infrastructure in parallel. A significant contributor to the size, mass, and power requirements of current Mars orbiters is the size of the communications hardware and solar arrays required to transmit large quantities of data back to Earth. Even if an orbiter does not generate large amounts of data itself, all orbiters since the year 2000 from NASA and ESA have been required or encouraged to also act as data relays for the variety of surface landers and rovers. Offloading the “trunkline”, or Mars-Earth section of the communications route to the larger LightShip spacecraft allows the passenger science spacecraft to have far smaller and lighter communications systems, bringing the development of them within reach of smaller space agencies and allowing large agencies to fly more if they wish. On all LightShip missions, available payload of opportunity slots could be awarded to any Member or Associated State of ESA, including nations with cooperation agreements such as Canada.

The first of hopefully many flights in the LightShip initiative will carry the SpotLight mission as its passenger. SpotLight is an orbiter focusing on high resolution imagery of the surface, with a high-resolution imager and medium-resolution context imager being the primary payload suite. These imagers, along with a potential payload of opportunity currently undergoing proposal evaluation, will produce large quantities of data that will be transferred primarily through LightShip.

Notably, SpotLight will not actually be delivered to its operational orbit by LightShip, instead separating during interplanetary cruise and independently entering Mars orbit.  This leaves LightShip free to go directly to its operational communications orbit and begin demonstrating its communications and navigation systems.

LightShip-1 itself is primarily tasked with being the first node of ESA’s future Mars communications and navigation constellation, which will offer continuous data relay and navigation capabilities to Mars orbiters, landers, rovers, and potentially even eventual human missions. The mission is currently in Phase A/B1 undergoing an industry-led preliminary design effort. In the ESA mission development process, Phase A (feasibility) and Phase B1 (preliminary design) are performed for the same mission requirements in parallel by 2-3 industry consortiums, with a single group being selected to continue their design and eventually build the final mission. LightShip-1 should complete Phase B1 in the second quarter of 2027 but will need to wait for its implementation phase to be funded by ESA’s member states at its triennial meeting of the ESA Council’s Ministerial level (also known as CM28). This will seemingly lead to a roughly 18-month stretch of downtime before implementation can begin. Another activity that is currently ongoing and could extend into that gap is the definition of 4 different satellite platforms that can be used to design LightShip’s passenger interfaces for a variety of passengers, both in type and number. A single LightShip can carry multiple different types of single large passenger science spacecraft or up to 12 individual smallsat passengers, enabling a very wide variety of possible missions.

The high levels of scientific return from Mars in recent years are in large part due to the existing network of orbiting relays that have surrounded the planet since the early 2000’s. Their large and powerful communications systems enable high data rates to both Earth and surface assets without requiring those assets to have equally large systems for Direct-to-Earth communication. For example, the Curiosity and Perseverance rovers only have small hexagonal antennas but return the majority of their data via these relays. This network, composed entirely of NASA and ESA science orbiters with relay systems added, is slow to grow and rapidly aging.

One of the most important spacecraft in the fleet is Mars Odyssey, launched in 2001, which has fewer than 3 kg of fuel remaining and regardless of funding will likely be decommissioned within the next fiscal year. The Mars Reconnaissance Orbiter (2005) is also beginning to fail and shut down systems, but is expected to be able to last in its relay role to roughly 2030. MAVEN (2013) and ESA’s Trace Gas Orbiter (2016) will be around likely until the mid-2030s.

If more relays are not launched soon, then the 2030s will see a massive drop-off in the ability to return data from Mars. Science orbiters are long to develop, expensive, and cannot be flown frequently due to their unique payloads. With the slowdown in new missions over the last several years and the increasing desire to make spacecraft smaller and simpler, a paradigm change is required if Mars science is to be maintained and to support future Humans to Mars initiatives, which ESA is actively planning to be a partner in. 

NASA has expressed a strong desire for dedicated infrastructure orbiters, and since 2023 is pursuing commercial services options as an operating model. With $700 million for a Mars Telecommunications Orbiter provided in the One Big Beautiful Bill Act, formulation work on the first of these commercial relays could begin soon. In 2022, ESA decided to pursue their own dedicated relay constellation, which was named MARCONI (Mars Communication and Navigation Infrastructure) after the italian radio pioneer. LightShip offers a carrier for the MARCONI system in order to serve the infrastructure role desired by both NASA and ESA while also enabling lower cost passenger spacecraft and hosted science instruments, and SpotLight will also serve as an additional low-orbit relay while MARCONI and any NASA relays are deployed.

While an entire independent communications and navigation constellation would be a big step up for ESA’s capabilities, the agency is already developing a large, long-lasting Mars orbiter whose primary function is to carry a hosted payload and act as a communications relay. The Mars Sample Return initiative’s Earth Return Orbiter is at an advanced stage of development, with its Critical Design Review (CDR) completed on July 5th, 2024, and the LightShip concept is similar enough in technical requirements that much of the Earth Return Orbiter work could likely be leveraged. 

In parallel with MARCONI and LightShip, ESA is beginning work on the Mars Entry, Descent, and Landing (MEDaL) concept. Key to Strategy2040, ESA’s new set of longer-term policy objectives and how the science and exploration programs will achieve them, MEDaL envisions a roadmap of missions and associated technology development that will improve landing accuracy from 100s of kilometers to less than 7 kilometers and eventually to pinpoint landings within tens of meters of the target point, while also increasing the allowable mass of landed payloads. However, ESA and its Member States are still in the process of defining the exact architecture, requirements, and included technologies. Specific flight demonstrations for these technologies could be included but would be funded as part of a follow-on effort. The first mission using the MEDaL technologies and architecture is due to launch in 2035, but that date is dependent on the state of ESA’s Mars program at the time and support from Member States.

This level of ambition is in line with ESA’s new long term policy goals of gaining true autonomy and self-sufficiency in space exploration and becoming an equal partner to the likes of the USA or China, collected in the Strategy2040 document. As previously discussed by Space Scout, Strategy2040 shows a leadership commitment to new technologies to support Europe-led human and robotic exploration of the Moon and Mars over the next few decades. Their ability to meet these goals on time will be very dependent on the outcomes of CM25 and future meetings like it, but if funding is secured there is no reason it cannot be done.

Both LightShip and MEDaL, combined with ESA’s extensive Earth science, Planetary science, and Artemis assets and programs, enable an interesting perspective on what Strategy2040 is trying to accomplish: ESA’s envisioned future state is analogous to a slightly smaller JPL. The Pasadena laboratory develops and operates missions across the fields of Astrophysics, Earth science, Planetary science, and conducts a great deal of technology development. ESA is already present and accomplishing significant strides in all of these areas, but Strategy2040 aims to greatly expand this presence. 

ESA is currently the primary developer of the EU’s Copernicus earth observation programme, implemented via the Sentinel series of satellites and orbiting payloads, providing significant quantities of information on land deformation, sea level, land use, climate change, and more. They produced the most detailed ever map of the cosmic microwave background with the Planck mission and significantly contributed to the James Webb Space Telescope. They were the first to land on a cometary nucleus with Rosetta and a celestial body past Mars with Huygens. 

Strategy2040 directs these accomplishments to be superseded by the implementation of many groundbreaking missions across both Astrophysics and Planetary Science, as well as continued investment into and new undetermined missions in Earth Science. In Astrophysics, there are the first dedicated European exoplanet detection and characterization missions (PLATO and ARIEL) and the first in-space and most sensitive gravitational wave observatory ever built (LISA). In Planetary Science, there is the first visit to a pristine comet (Comet Interceptor), the first life-detection and in-situ exploration mission to Enceladus, one of the first thorough explorations of Venus since the 1980s (EnVision), the LightShip program and associated low-cost Mars missions, and the full execution of the first dedicated mission to Ganymede (JUICE). Many of these projects are already launched or in active development, but should funding be allocated for all of this expansion, ESA will truly come into its own as a space science agency on the level of NASA, JAXA, ISRO, and the Chinese Academy of Sciences, able to pack a punch and lead missions to anywhere it chooses.

Thank you to Dr Clare Parfitt, Mars Exploration Study Lead for the European Space Agency’s Exploration Preparation Research and Technology (ExPeRT) team, for clarifying comments and explanations!