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Price, Hoppy

Publications and source records attributed to Price, Hoppy.

At least 19 records

A Systems Margin Metric for Capability Above Basic Estimates

A systems margin metric is described that indicates the total system performance capability above the basic estimates (CABE) for mass, power, energy, propellant, V, ISP, computer performance, and any other design parameter with a defined margin. This concept normalizes all terms for contingency, margin, growth allowance, and reserves to the amount that the basic mass of the vehicle could grow if each of those “room to grow” terms were released. The CABE metric is intended to provide a uniform indication of the total performance margin of a system at a given point in the project life cycle. The CABE metric can also provide a normalized means to trade the “room to grow” terms between various resources in order to solve system performance issues as they arise. For example, the CABE percentage for ISP margin could be equally traded with the CABE percentage for power margin.

Lepsch, Roger

Concept for 2033 Crewed Mars Orbital Mission with Venus Flyby

The 2033 Mars launch period provides a unique opportunity for a round trip mission with a total flight time of only 1.6 years. A concept is presented to perform a crewed Mars orbital mission in 2033 that would minimize development and mission risk by using conventional hypergolic in-space propulsion stages with a common design. The Mars mission vehicle would include a Mars transit habitat, an Orion spacecraft, and chemical propulsion stages. It would be launched by a combination of SLS and commercial rockets to be aggregated in high Earth orbit or at the Lunar Gateway. The crew would launch to the mission vehicle in Orion as the final element in the assembly. After transit to Mars, the crew would spend about 30 days in a high Mars orbit and then return to Earth via a Venus flyby and gravity assist. A sunshade would be deployed for thermal control of the mission vehicle inside 1 AU. The crew would return directly to Earth in the Orion crew module, with the transit habitat being expended. The 2033 mission would not be a “one-off”, but could be a pathfinder for crew transport for landing missions to follow, perhaps starting as early as 2037.

Woolley, Ryan

A Science-Driven Mission Concept to An Exoplanet

A concept for a science-driven robotic mission to an exoplanet was developed by a team of scientists and engineers from NASA and academia. The concept and scope were based on key mission and science requirements designed to address the question: “What makes a flight mission to an exoplanet compelling, in terms of science return, compared to what we will be able to learn in the next few decades with large near-Earth telescopes or other remote sensing techniques such as a telescope at the Solar Gravity Lens Focus?” By thinking systematically through mission and science goals and objectives, key requirements were developed that would drive technology developments in all necessary aspects, not just on propulsion. Unique science measurements would be performed en route to the exoplanet, including exploring the environment in the outer regions of our solar system, the Oort Cloud, the local interstellar medium, and the astrospheric environment around the host star. One of the key mission science objectives, and one that addresses why a mission to an exoplanet is compelling, was to confirm and characterize life. This objective is fundamental and drives the need for a precursor exoplanet characterization program to search for Earth-centric biosignatures and also drives key aspects of the mission concept. The team concluded that a direct confirmation of life would require in situ observations and measurements which cannot be performed on a fast (~10% of the speed of light) flyby; thus, the mission would require a method to slow down, orbit, or send a probe to the exoplanet’s surface. This capability drives a trade between interstellar travel velocity, trip duration, and propulsion architecture, as well as a high level of onboard autonomy, including adaptive science data collection, on-board data processing, and analysis. This paper describes our mission concept, the key requirements, and open trades.

Bennett, Gary