That’s one small step for NASA’s lunar Gateway program, one moderate leap toward returning humans to the lunar surface in this decade.
Some of the earliest pieces of a return to the moon by American astronauts dubbed the Artemis project are falling into place with a string of contract awards for Gateway, NASA’s orbiting way station that would be used for crewed lunar landings and, eventually, deep space missions.
Among them is a contract award to SpaceX to launch early Gateway components, including the Power and Propulsion Element (PPE) and the Habitation and Logistics Outpost. HALO is being built by Northrop Grumman Space Systems.
Maxar Technologies is supplying PPE, a 60-kilowatt solar electric propulsion spacecraft that also will provide power, high-speed communications and attitude control. It will also provide the capability to move the Gateway to different lunar orbits, allowing a future lander to reach the moon’s poles where frozen water may exist in deep, permanently shaded craters.
Maxar is also a member of the Dynetics team competing to build a lunar lander. Other competitors are SpaceX and a team that includes Blue Origin, Lockheed Martin and Northrop Grumman.
As part of the PPE effort, TTTech Aerospace and RUAG Space will supply the Gateway’s Ethernet-based network platform, or what developers call the outpost’s central nervous system. TTEthernet consists of switches, network interface cards, software and network configuration tools that enable the prioritization and precise scheduling of deep space communications.
The networking platform is based on international interoperability standards for deep space missions forged by NASA along with the Canadian, European and Japanese space agencies. The avionics spec covers data link protocols and physical layer options for spacecraft interfaces.
TTTech (the company’s name is a derivation of “Time Triggered Technology”) said its Gateway network platform is based on its deterministic Ethernet approach, a framework that uses time scheduling to manage network traffic. The Gateway system could use the fault-tolerant network, for example, to converge high-priority real-time communications with “best-effort” traffic on a single Ethernet architecture.
A deterministic network would reduce latency, thereby guaranteeing critical and scheduled communications would get to and from ground controllers.
TTEthernet uses redundant and reliable network switches and interfaces designed for mission critical communications. The scheduling capability would allow mission controllers to prioritize voice and data communications while reducing transit times during deep space missions for critical spacecraft maneuvers, said Bob Richards, TTTech North America’s vice president for space.
Since the time-scheduled Ethernet network is based on international avionics standards, other space agencies “can tie into it,” Richards said in an interview. He added that engineers in TTTech’s Houston facility are working with Maxar to identify commercial TTEthernet platforms that can withstand the rigors of deep space missions.
“TTEthernet technology forms the backbone for inter-element data and network communications across the combined PPE-HALO spacecraft,” added Vince Bilardo, Maxar’s director for NASA programs.
TTTech and Zurich-based RUAG Space, which provides space qualified hardware, said they expect to deliver the first PPE network components to Maxar by the middle of 2021.
Maxar’s PPE would then be integrated with Northrop Grumman’s HALO component of the Gateway to be launched by a SpaceX Falcon Heavy rocket.
Just when those Gateway components will be launched is uncertain. While the NASA contract awards indicate some momentum for the ambitious Artemis project, which optimistically calls for a crewed landing by 2024, early Artemis flights do not require the Gateway. Hence, a source said, NASA views Gateway as “a long way in the future—too complicated and too expensive right now.”
Meanwhile, the massive Space Launch System that would propel astronauts to the moon has yet to fly. The first test firing of the SLS core stage’s main engines was cut short in January after just 67 seconds.
NASA delayed a second “hot fire” test last month, citing a valve issue. No data has been announced for rescheduling the test.