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Zachary Zoloty

Publications and source records attributed to Zachary Zoloty.

7 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS2022

Titan In-situ Resource Utilization (ISRU) Sample Return (TISR)

Titan is unique in the outer solar system in that it is the only moon with a thick atmosphere, and the only body in the solar system outside the Earth with liquid seas on its surface. The Titanian oceans, however, are seas of liquid hydrocarbons, and the rocks on the surface are solid water ice. Like other icy Moons of the outer solar system, beneath the ice crust, Titan also has a subsurface ocean. Rodriguez et al. refer to it as the “world with two oceans”, an organic-rich body with interior-surface-atmosphere interactions that are comparable in complexity to the Earth. [1] Titan is scientifically fascinating in many ways [2], [3], [4]. The Compass Team will emphasize just one here: Titan is a high priority target for astrobiology [4] [5] [6] [7] [8] [9] [10] [11]. It is a world with a surface and atmosphere rich in the complex organic compounds known as tholins. A detailed understanding of the nature of these complex compounds will require an analysis using a full laboratory on Earth. Because of its value to understanding the organic compounds of the outer solar system which may be the primordial building-blocks of life, return of samples from Titan to laboratories on Earth will be the primary goal of this mission. While this would give unprecedented science return, returning even a small sample from Titan using conventional technology would be tremendously difficult. Saturn is almost a billion miles from the Earth, about thirteen times farther than Mars. A return mission to Saturn requires such a large total-mission ∆V that, with conventional technology, the mass ratios required are prohibitive. Such a sample return would truly be “mission incredible.” But to date, a sample return mission from so distant a target has been assumed to be, not merely incredible, but mission impossible. The Compass Team has proposed [2] [12] that by manufacturing the propellant for the return to Earth using the resources available on Titan, such a mission becomes possible. The task of this report is to show that it is reasonable with credible space technology.

Titan↗
NASA NTRS2022

Mission Incredible: A Titan Sample Return Using In-Situ Propellants

An analysis of the use of in-situ volatile propellants for a sample return mission from Titan shows that this mission should be feasible. Such a mission would be invaluable for its science return, and its contribution to our understanding the origins of organic compounds in the solar system and our place in the universe.

Titan↗
NASA NTRSDate not supplied

A 1 MW Solar Electric and Chemical Propulsion Vehicle for Piloted Mars Opposition Class Missions

Previous investigations have extensively explored crew missions to and from Mars, with a prevailing approach termed the 'conjunction' class, necessitating an approximately 500-day stay at Mars for a cost-effective return. However, this configuration results in a mission duration exceeding 1000 days (roughly 3 years). In order to reduce crew health and surface operations risks, a shortened mission duration of 850 days is being explored by using a short ~30 day Mars surface stay and a ‘opposition’ class approach. A non-nuclear approach is possible by combining solar electric propulsion and a chemical stage. While past mission concepts for the conjunction missions also used solar electric propulsion they limited the SEP power to <700 kW. In order to achieve the 850 day round trip more SEP power is needed. A 1MW class SEP-Chem vehicle was found sufficient to perform the 850 day mission. The biggest challenge for the design will be the large, high power solar arrays, mainly from their deployment and stability. This work describes the design of the SEP-Chem vehicle, assembled in a Near Rectilinear Halo Orbit (NRHO) and employing super-heavy class and the Space Launch System (SLS) launchers.

SEP-Chem↗
NASA NTRSDate not supplied

Trajectory Design for a Solar Necklace of Repurposed Gateway Logistics Modules

The Solar Necklace mission concept, initially formed from a study conducted by the Compass Team at NASA’s Glenn Research Center, aims to maximize the scientific potential of a spacecraft’s lifetime by redefining their proposed disposal trajectories. By repurposing logistics modules (LMs) initially designated for heliocentric disposal after servicing NASA’s Gateway, a constellation of spacecraft could be placed around the sun. This paper assesses the feasibility of reusing vehicles equipped with solar science packages, sending them into a heliocentric orbit to enhance solar science capabilities, and potentially provide early warning capabilities for future piloted spacecraft. A comprehensive analysis of the trajectory design aspects for the Solar Necklace mission was performed, highlighting key components of the study such as Earth-relative drift rates, ∆v requirements, Earth-flyby opportunities, number of lunar flybys, and final orbital state parameters. Additionally, the paper serves as a proof-of-concept for the repurposing of Gateway LMs using convenient, low-cost methods of advancing solar science, space weather understanding, and climate research.

Mission Design↗
NASA NTRSDate not supplied

SERENE: Saturn Enceladus Return Explorer with Nuclear Electric Propulsion

A ‘quick’ Enceladus sample return mission concept was developed based on the scientist recommendations at the recent ‘Accelerating Space Science with Nuclear Technology Workshop’. The Nuclear Electric Propulsion spacecraft assumed a follow-on 40 kWe nuclear reactor using the demonstrated 40 kWe Fission Surface Power system, expected in the early 2030s. The NEP vehicle also utilized a set of NEXT-C ion thrusters as well as planned Artemis commercial launchers. By launching the 40 kW NEP vehicle on a Starship and adding the propellants of 15 tankers, the 27t probe could be sent on a direct trajectory to Saturn (no Earth or Jupiter flybys) where NEP was used for Saturn capture, spiral down, spiral up and return to the Earth. A small lander obtained the surface Enceladus sample. Using the 40 kW NEP provided a round-trip time of only 16.5 years. A second option was more attractive from a science perspective whereby the NEP vehicle would deliver a large, 6t chemical lander to low Enceladus orbit where it would grab and return a sample to Earth (similar to the recent Orbilander design but in reverse). After deploying the lander, the NEP vehicle would stay in Saturn space performing a moon tour by orbiting four more moons and mapping the large moon of Titan. This option took slightly longer (18.5 yrs) due to the chemical return leg limitations. Both options demonstrated the agility, payload capability, and sample return goals the workshop recommended. An all-chemical option with two stages was roughly analyzed but took 21.5 yrs and required a Jupiter gravity assist.

Nuclear Electric Propulsion↗