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Kurt Hack

Publications and source records attributed to Kurt Hack.

5 records
All sourcesNASA NTRSDOE OSTI
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Attitude Profile Reference for the Earth Orbit Raising Phase of NASA Gateway’s Co-Manifested Vehicle

As part of NASAs lunar exploration Artemis program, the agency is designing a Gateway to orbit8near the moon and provide long term support of a sustained lunar presence at the moon’s south pole.9The first element launched for the Gateway is the Co-Manifested Vehicle (CMV), comprised of the10Power and Propulsion Element (PPE) and Habitation and Lunar Outpost (HALO). The PPE Mission11Design team of McGuire & et. al (2021) has developed a Design Reference Mission (DRM) trajectory12for CMV’s Earth Orbit Raising (EOR) mission phase, which provides the vehicle’s 3 degrees of freedom13(DoF) trajectory information during the approximately yearlong spiral out from low Earth orbit and14into the lunar near-rectilinear halo orbit (NRHO). In tandem, the PPE GN&C team is developing a15high-fidelity and fine temporal resolution 6DoF model of the CMV spacecrafts GN&C performance16for delivery to the Gateway team; this work acts to bridge the gap between Mission Designs 3DoF17reference and detailed GN&Cs attitude simulation.

Guidance Navigation and Control↗
NASA NTRSDate not supplied

Overview of the Lunar Transit Trajectory Performed by the Power and Propulsion Element of NASA’s Gateway

NASA has committed to returning to the moon, landing the first woman and the next man on its surface. To support a sustained lunar presence, NASA is designing an orbital platform to be assembled in an orbit near the moon called the Near Rectilinear Halo Orbit (NRHO). This platform is known as the Gateway and its purpose it to support missions primarily to the lunar south pole. As NASA continues to study ways to reduce the cost of lunar exploration, a simplification implemented in 2020combinedthe first two elements of the Gateway, the Power and Propulsion Element (PPE) and NASA’s Habitation and Logistics Outpost (HALO), onto a single commercial launch vehicle (CLV). When launched together, the PPE and HALO make up the first two elements of NASA’s Gateway and exceed the performance capacity of commercially available launch vehicles to deliver directly to the moon. The delivery of the Gateway is enabled by and takes advantage of the high efficiency of the PPEs high-power Solar Electric Propulsion (SEP) system to transfer a significant starting mass from an initial Earth orbit to final insertion into the NRHO. The PPE is a 50-kW class high power solar electric propulsion stage comprised of two different types of electric thruster strings. The SEP system is operated in two different modes, a high thrust and high Isp (specific impulse), to both maximize the final delivered mass and attempt to minimize the time spent in the Van Allen Belts early in the transit trajectory. Additionally, this SEP system brings the capability to the assembled Gateway for transfer between orbits in cislunar space. This paper captures the preliminary low thrust lunar transfer reference trajectory to be flown by the PPE it delivers itself and HALO via a spiral trajectory from launch vehicle insertion to insertion into the NRHO as well as a preliminary reference round trip transfer of the Gateway from the NRHO to a Distant Retrograde Orbit (DRO) using the PPE. Once in its final NRHO, the Gateway is being designed to enable long duration human and robotic exploration of the lunar south pole as a precursor to Mars. The Gateway’s low thrust lunar transit trajectory is envisioned to prove out the application of and flight of a high-power SEP system as a demonstration of technologies applicable to the enabling of future human space exploration.

human exploration↗
NASA NTRSDate not supplied

Application of Solar Electric Propulsion to the Low Thrust Lunar Transit of the Gateway Power and Propulsion Element

NASA has committed to returning to the moon, landing the first woman and the next man on its surface. To support a sustained lunar presence, NASA will assemble an orbital platform in a quasi-stable orbit near the moon known as a Near Rectilinear Halo Orbit (NRHO). This platform, known as Gateway, will support long duration exploration missions targeting the lunar south pole. An architecture simplification implemented in 2020 combined the first two elements of the Gateway together onto a single commercial launch vehicle (CLV). When launched, the Power and Propulsion Element (PPE) and the Habitation and Logistics Outpost (HALO) will form the initial capability of NASA’s Gateway. The PPE, with its high-power Solar Electric Propulsion (SEP) system, will propel the combined vehicle from an elliptical Earth parking orbit to the target NRHO. A transit of such a large mass, delivered to the moon from a single launch vehicle, is only made possible using the highly efficient SEP system. Delivering the same mass via more traditional chemical propulsion systems would require major modifications to the mission architecture, significantly more propellant mass, and could necessitate the use of a more powerful launch vehicle. This paper describes the design of the nominal low-thrust transit by which Gateway will be delivered to the NRHO utilizing the PPE SEP system. Additionally, this paper captures how the unique capabilities of the PPE electric propulsion system have guided the design of the trajectory and how mission requirements have, in turn, impacted the maturation of the SEP system.

electric propulsion↗
NASA NTRSDate not supplied

Application of Solar Electric Propulsion to the Low Thrust Lunar Transit of the Gateway Power and Propulsion Element

NASA has committed to returning to the moon, landing the first woman and the next man on its surface. To support a sustained lunar presence, NASA is designing an orbital platform to be assembled in a semi-stable orbit near the moon called the Near Rectilinear Halo Orbit (NRHO). This platform is known as the Gateway and its purpose it to support missions primarily to the lunar south pole. As NASA continues to study ways to reduce the cost of lunar exploration, a simplification implemented in 2020 was combining the first two elements of the Gateway together onto a single commercial launch vehicle (CLV). When launched together, the Power and Propulsion Element (PPE) and NASA’s Habitation and Logistics Outpost (HALO) make up the Co-Manifested Vehicle (CMV). The PPE, a high-power Solar Electric Propulsion (SEP) Stage, will propel the combined stack from a low elliptical orbit to a semi stable orbit near the moon known as a Near Rectilinear Halo Orbit (NRHO). A transit of such a large mass, delivered to the moon from a single launch vehicle is only made possible by the use of the highly efficient SEP low thrust propulsion system. Delivering the same mass via more traditional chemical propulsion systems would require multiple launches and significantly more propellant. This paper captures an overview of the PPE’s SEP system, the lunar transit it will perform to deliver these first two elements of NASA’s Gateway to the NRHO with a comparison of a chemical system performing the same lunar transit to illustrate how SEP enables NASA’s Gateway.

electric propulsion↗