Synopsis
The paper describes the HelioSwarm mission, a NASA Medium Explorer (MIDEX) mission led by the University of New Hampshire under NASA’s Heliophysics Division. The mission aims to study turbulence in the solar wind plasma using a unique “swarm” of spacecraft.
The HelioSwarm observatory consists of 9 spacecraft – a larger “Hub” spacecraft and 8 smaller “Node” spacecraft. The Nodes are attached to the Hub for launch, then released in pairs over 2 weeks once in the science orbit. All spacecraft carry identical instrument suites, with additional instruments on the Hub. The Hub relays data between Nodes and the ground in a hub-and-spoke topology.
The science orbit is a High Earth Orbit that is resonant with the Moon’s orbit. This provides solar wind sampling in different regimes as the orbit precesses over a year. The Node spacecraft have slightly different orbits, producing changing formations and separations optimized for multiscale turbulence measurements.
The Hub is based on a Northrop Grumman ESPA ring, with large solar arrays and propulsion for orbit maneuvers. The Nodes use Blue Canyon Technologies’ Venus bus. Both have 3-axis stabilized attitude control and S-band communications.
The mission timeline includes launch, phasing loops, lunar swingby, and orbit maneuvers to achieve the science orbit. Node deployments and commissioning occur over 2 months before starting the 1-year science phase. Operations focus on maintaining the swarm geometry, science data collection near apogee, and high-rate downlink near perigee.
A key aspect is the combined science and flight dynamics optimization of the swarm trajectories for multiscale tetrahedral geometries. Custom tools visualize the changing swarm configurations.
As a pathfinder for future swarm missions, HelioSwarm exemplifies close collaboration between science, engineering, and operations. It leverages both large and small spacecraft capabilities, while meeting NASA mission assurance requirements as a Class C mission.
The mission is led by UNH, with partners including NASA centers, aerospace companies, and academic institutions in the US and Europe. HelioSwarm was selected under NASA’s Explorer program to advance heliophysics science and contribute to future swarm-based space physics missions.
