James Horton

• Master of Science
• Systems Engineer at Aerojet Rocketdyne

NASA’s accelerated Artemis program goal of landing astronauts on the moon within the next five years, by 2024, and establishing a sustained presence on and around the Moon by 2028 will require routine delivery of science and consumables at the Gateway lunar orbital outpost which will sit in a lunar near rectilinear halo orbit (NRHO). Due to that sc...

NASA and industry are studying future human exploration missions to Mars that occur across multiple mission opportunities between 2030 through 2050. Aerojet Rocketdyne is supplementing previous work with Conjunction Class round-trip Mars missions by studying Opposition Class missions. Opposition Class missions have the advantage of shorter total mi...

NASA’s accelerated Artemis program goal of landing astronauts on the moon within the next five years, by 2024, and establishing a sustained presence on and around the Moon by 2028 will require routine delivery of science and consumables at the Gateway lunar orbital outpost which will sit in a lunar near rectilinear halo orbit (NRHO). Due to that sc...

After a fifty year absence, NASA's return to the lunar surface under the Artemis Program-for long term human exploration and utilization-is driving commercial and academic opportunities for small satellite and small lander platforms (e.g., Commercial Lunar Payload Services program-CLPS). Bipropellant thrusters are a reliable, low risk, and flight p...

Impulsively-efficient low-enriched uranium (LEU) nuclear thermal propulsion (NTP) and nuclear-electric propulsion (NEP) are two near-term technologies that can reduce the logistics, trip time, and risks associated with long-duration crewed missions to Mars starting in the 2030's. During preliminary mission planning, interplanetary trajectories are...

View Video Presentation: https://doi.org/10.2514/6.2021-3611.vid Since 2016, AR has been working with NASA and members of industry as part of the NASA Space Technology Mission Directorate. The initial goal of this project was to determine the feasibility and affordability of a low enriched uranium (LEU)-based nuclear thermal propulsion (NTP) engine...

View Video Presentation: https://doi.org/10.2514/6.2021-3610.vid The long term, sustained exploration of Mars will require the focused efforts of a collective of national space agencies, public and private industry, and academia. The goal of this exploration will not be to just plant a flag and leave a boot print, but to continue beyond the first m...

Nuclear thermal propulsion (NTP) has been extensively researched as a potential main propulsion option for human Mars missions. NTP's combination of high thrust and high fuel efficiency makes it an ideal main propulsion candidate for these types of missions, providing architectural benefits including smaller transportation system masses, reduced tr...

NASA, Aerojet Rocketdyne, and other members of industry have been performing engine and mission trade studies to examine low enriched uranium (LEU) approaches for nuclear thermal propulsion (NTP) powered vehicles. Based upon commercial terrestrial technology to reduce proliferation and security concerns, LEU provides a path to a more affordable “ne...

After a 50+ year absence, NASA’s planned return to the Moon for long-term exploration and utilization is driving government and private investment in new technologies to affordably and safely land astronauts and logistics – food, science equipment, and cargo – on the lunar surface. Small commercial (< 250 kg payload) to medium class landers (500 –...

Nuclear thermal propulsion (NTP) has been extensively researched as a potential main propulsion option for human Mars missions. NTP's combination of high thrust and high fuel efficiency makes it an ideal main propulsion candidate for these types of missions, providing architectural benefits including smaller transportation system masses, reduced tr...

The future of human exploration missions to Mars is dependent on solutions to the technology challenges being worked on by the National Aeronautics and Space Administration (NASA) and industry. One of the key architecture technologies involves propulsion that can transport the human crew from Earth orbit to other planets and back to Earth with the...

NASA and industry are studying future human exploration missions to Mars that occur across multiple mission opportunities between 2030 through 2050. Aerojet Rocketdyne is supplementing previous work with Conjunction Class round-trip Mars missions by studying Opposition Class missions. Opposition Class missions have the advantage of shorter total mi...

Aerojet Rocketdyne is working with NASA, the Department of Energy, and other industry to define a more affordable path to nuclear propulsion and power use for lunar, Mars and broader solar system exploration missions. Aerojet Rocketdyne's (AR) recent work builds on the legacy design, analysis, and testing knowledge gained from the Rover/NERVA (Nuc...

The implementation of electric propulsion systems on Earth orbiting satellites has dramatically improved the fuel efficiency, and in turn the capability and resilience, of such satellites when compared to their chemical propulsion counterparts. Electric propulsion systems flown to date have achieved power levels up to 5 kW per string for GEO commun...

NASA and its international partners have identified an exciting plan for opening up cislunar space and making the first steps toward human exploration of Mars in the 2020s. 1 Aerojet Rocketdyne is working with NASA to develop higher power Electric Propulsion (EP) in support of this vision. The Advanced Electric Propulsion System (AEPS) is being dev...

Since 2016, Aerojet Rocketdyne (AR) has been working with NASA and other industry partners to improve the design and increase the feasibility of Low Enriched Uranium (LEU) NTP engine systems that have clear programmatic and cost benefits over older Highly Enriched Uranium (HEU) designs. Part of this study effort is examining potential value-added d...

Studies of Nuclear Thermal Propulsion (NTP) over the past several decades, and updated most recently with the examination of Low Enriched Uranium (LEU), have shown nuclear propulsion is an enabling technology to reach beyond this planet and establish permanent human outposts at Mars or rapidly travel to any other solar system body. The propulsion n...

If humans are to reach beyond this planet and establish permanent outposts at Mars or any other solar system body, advanced propulsion will be needed. Optimum advanced propulsion needs high thrust to operate within the deep gravity well of a planet and also needs to provide high propulsive efficiency for rapid travel and reduced total spacecraft ma...

Nuclear Thermal Propulsion (NTP) is a proven technology that provides the performance required to enable benefits in greater payload mass, shorter transit time, wider launch windows, and rapid mission aborts due to its high specific impulse (Isp) and high thrust. Aerojet Rocketdyne (AR) has stayed engaged for several decades in working NTP engine s...

In December 2017 the current administration made a single sentence change to US Space Policy Directive-1 which has refocused the country’s space explorations efforts on a “return of humans to the Moon for long-term exploration and utilization.” With this mandate the National Aeronautics and Space Administration has centered its near-term developmen...

NASA and industry are studying future human exploration missions to Mars that occur across multiple mission opportunities between 2030 to the late 2050's. Aerojet Rocketdyne (AR) has been analyzing ballistic transfers for Earth to Mars for roundtrip missions over an even grid of departure dates and transfer times during those opportunities. Aerojet...

The future of human exploration missions to Mars are dependent on solutions to the technology challenges being worked by NASA and industry. One of the key architecture technologies required to successfully send human to Mars involves selecting the propulsion system that can transport the crew from Earth orbit to Mars and back to Earth with the lowe...

Rocket engine conceptual design using multi-disciplinary analysis and optimization. Design-to-cost techniques explored.

Future human exploration missions to Mars are being studied by NASA and industry. Several approaches to the Mars mission are being examined that use various types of propulsion for the different phases of the mission. The choice and implementation of certain propulsion systems can significantly impact mission performance in terms of trip time, spac...

Future human exploration missions to Mars are being studied by NASA, industry and academia. Many approaches to the Mars mission are being examined that use various types of propulsion for the different phases of the mission. The choice and implementation of propulsion system options can be optimally determined based on specific mission criteria suc...

Future human exploration missions to Mars are being studied by NASA and industry. Several approaches to the Mars mission are being examined that use various types of propulsion for the different phases of the mission. The choice and implementation of propulsion system options can significantly impact mission performance in terms of trip time, space...

Future human exploration missions to Mars are being studied by NASA and industry. Several approaches to the Mars mission are being examined that use various launch vehicle configu-rations and different types of propulsion for the various phases of the mission.. Understand-ing the key impacts of key systems being considered for both cargo transfer a...

Aerojet Rocketdyne initiated development of its AR1 booster engine in 2014 in response to the urgent national need. Two AR1 Engines are planned for the Atlas V vehicle family, or next generation Atlas launch vehicle. The two AR1 engine set design goal is to meet or exceed the current payload performance provided by the multiple configurations withi...

This study examines the impact of the launch capabilities provided by the planned Space Launch System (SLS) Block 2 vehicle on the solar electric propulsion (SEP) power levels required for large cargo prepositioning missions to Mars orbit. Our analysis shows that the additional launch capability planned for the SLS vehicle enables a dramatic reduct...

Prevailing launch vehicle and liquid rocket engine design philosophies derived from 1950s research efforts focus on delivering optimum performance and minimizing weight. Performance optimization has been sought on almost every major booster and upper stage engine typically requiring rocket propulsion technologies that push the components to their t...

This paper is a summary of Space Shuttle Main Engine (SSME) off-nominal testing that occurred during 2008 and 2009. During the last two years of planned SSME testing at Stennis Space Center, Pratt & Whitney Rocketdyne worked with their NASA MSFC customer to systematically identify, develop, assess, and implement challenging test objectives in order...