John O. Elliott

Design Concept for a Nuclear Reactor‐Powered Mars Rover

A study was recently carried out by a team from JPL and the DOE to investigate the utility of a DOE‐developed 3 kWe surface fission power system for Mars missions. The team was originally tasked to perform a study to evaluate the usefulness and feasibility of incorporation of such a power system into a landed mission. In the course of the study it became clear that the application of such a power system was enabling to a wide variety of potential missions. Of these, two missions were developed, one for a stationary lander and one for a reactor‐powered rover. This paper discusses the design of the rover mission, which was developed around the concept of incorporating the fission power system directly into a large rover chassis to provide high power, long range traverse capability. The rover design is based on a minimum extrapolation of technology, and adapts existing concepts developed at JPL for the 2009 Mars Science Laboratory (MSL) rover, lander and EDL systems. The small size of the reactor allowed its...

Mission Concept for a Nuclear Reactor‐Powered Mars Cryobot Lander

Recently, a team from JPL and the DOE carried out a study to investigate the utility of a 3 kWe surface fission power system for Mars landed missions. In the course of the study it became clear that the application of such a power system was enabling to a wide variety of potential missions. Of these, two concepts were developed, one for a stationary lander and one for a reactor‐powered rover. This paper discusses the design of the lander mission, which was developed around the concept of landing a cryobot on the Mars north polar ice cap. The cryobot is designed to bore through the entire 2–3 km thickness of the ice cap, providing a picture of the Martian climate spanning more than a million years of Martian history. The high sustained power available from the reactor system proves to be an ideal match for this mission design, enabling a level of science return unavailable from any alternative power sources. The lander design is based on a minimum extrapolation of technology, drawing heavily on the existin...

NEPTranS; A Shuttle‐Tended NEP Interplanetary Transportation System

Recently, a study was performed by a team from JPL and the DOE to develop a mission architecture for a reusable NEP Interplanetary Transfer Vehicle, a “Space Truck”. This vehicle is designed to be used for delivery of payloads from Earth to a variety of destinations, including Mars and Venus, dependent on mission needs. In addition to delivering payloads to the target bodies, the vehicle is designed to perform autonomous rendezvous and capture of sample return capsules at the destination for return to Earth. In order to maximize the utility of the vehicle, its design is optimized for servicing between missions with the Space Shuttle. Fuel tanks, ion thrusters, and Power Management and Distribution electronics are all on‐orbit replaceable units, located at the payload interface end of the spacecraft to ensure a minimal radiation dose to the Shuttle and crew during maintenance and resupply operations. Operational flexibility is maximized through the use of replaceable fuel tanks and thrusters, allowing tailoring of fuel load to any given destination and payload mass. This paper discusses the preliminary design developed for the NEP Interplanetary Transfer Vehicle, including its configuration and design features, and outlines the concept for mission design, including discussion of unique requirements for launch, deployment and operations with the Space Shuttle, and rendezvous and servicing by the Shuttle in Earth orbit following a return from each target destination.Recently, a study was performed by a team from JPL and the DOE to develop a mission architecture for a reusable NEP Interplanetary Transfer Vehicle, a “Space Truck”. This vehicle is designed to be used for delivery of payloads from Earth to a variety of destinations, including Mars and Venus, dependent on mission needs. In addition to delivering payloads to the target bodies, the vehicle is designed to perform autonomous rendezvous and capture of sample return capsules at the destination for return to Earth. In order to maximize the utility of the vehicle, its design is optimized for servicing between missions with the Space Shuttle. Fuel tanks, ion thrusters, and Power Management and Distribution electronics are all on‐orbit replaceable units, located at the payload interface end of the spacecraft to ensure a minimal radiation dose to the Shuttle and crew during maintenance and resupply operations. Operational flexibility is maximized through the use of replaceable fuel tanks and thrusters, allowing tail...

Lunar Fission Surface Power System Design and Implementation Concept

At the request of NASA’s Exploration Systems Mission Directorate (ESMD) in May of 2005, a team was assembled within the Prometheus Project to investigate lunar surface nuclear power architectures and provide design and implementation concept inputs to NASA’s Exploration Systems Architecture 60‐day Study (ESAS) team. System engineering tasks were undertaken to investigate the design and implementation of a Fission Surface Power System (FSPS) that could be launched as early as 2019 as part of a possible initial Lunar Base architecture. As a result of this activity, the Prometheus team evaluated a number of design and implementation concepts as well as a significant number of trades associated with lunar surface power, all culminating in a recommended approach. This paper presents the results of that study, including a recommended FSPS design and implementation concept.

The "Billion Dollar Box" Study of Science Missions to Saturnian Satellites

Cassini/Huygens (C/H) mission investigations verify Saturnian satellites Titan and Enceladus as objects of intense interest to planetary scientists and astrobiologists. Recently NASA commissioned a study of potential relatively low-cost missions to these icy satellites, led by the Jet Propulsion Laboratory (JPL) with science and engineering teams from prominent universities, FFRDCs, and NASA centers. NASA was interested in determining whether there are scientifically viable missions to Titan or Enceladus within the constraints of a (possibly slightly expanded) New Frontiers mission. The C/H missions extremely capable instrumentation and thorough investigation of the Saturn system make that a difficult, though not obviously impossible, task. Any such mission must exceed C/H capabilities (in, for instance, imaging coverage or resolution, or range of constituents identifiable) to be scientifically worthwhile. Beginning in October 2006 these teams assessed science objectives for the two destinations and surveyed architectural options for implementing worthwhile subsets of the global lists of science objectives, attempting to find mission concepts both scientifically justifiable and within New Frontiers constraints. These studies were completed in early 2007 and the somewhat surprising results, that there appear to be no such missions, reported to NASA. This presentation gives the results of the studies and examines interesting individual missions.

Concept for a radioisotope powered dual mode lunar rover

Over three decades ago, the Apollo missions manifestly demonstrated the value of a lunar rover to expand the exploration activities of lunar astronauts. The stated plan of the new Vision for Space Exploration to establish a permanent presence on the moon in the next decades gives new impetus to providing long range roving and exploration capability in support of the siting, construction, and maintenance of future human bases. The incorporation of radioisotope power systems and telerobotic capability in the design has the potential to significantly expand the capability of such a rover, allowing continuous operation during the full lunar day/night cycle, as well as enabling exploration in permanently shadowed regions that may be of interest to humans for the resources they may hold. This paper describes a concept that builds on earlier studies originated in the Apollo program for a Dual Mode (crewed and telerobotic) Lunar Roving Vehicle (DMLRV). The goal of this vehicle would be to provide a multipurpose i...

Deep subsurface exploration of planetary ice enabled by nuclear power

The exploration of subsurface ice environments on the Mars polar caps, as well as the icy moons of the outer solar system, has gained increasing attention in recent years. A number of mission concepts have been developed to varying degrees to explore these subsurface regions. In prior studies the ability to access these environments to significant depths has been limited primarily by the power systems available for application to such missions. The current state of development of compact nuclear fission power sources, however, brings new conceptual opportunities for deep, long-term exploration in planetary ice, enabling missions to explore the full depth of the Martian ice caps and potentially to explore the icy shells of the Jovian moons. In this paper a complete mission design is presented for one such mission to the north pole of Mars. The mission concept includes a design for a potential lander configuration based on adaptation of current technology as developed in early studies for the Mars Science Laboratory (MSL) project. The mission design also makes use of the basic entry, descent, and landing (EDL) proposed for MSL, with modifications to accommodate the configuration and mass of the ice probe and other landed elements. Two alternative methods of ice exploration are discussed, both enabled by a small 15 kW (thermal) surface fission power system. The first of these designs considers a lander-mounted reactor configuration with the reactor supplying 3 kW of electrical power to an electrically heated ice probe, based on designs currently in development and tested in terrestrial applications. The second concept considers a design in which the nuclear reactor is incorporated directly into the body of the ice probe, allowing the full thermal output of the reactor to be used in melting the ice. Each of these concepts brings distinct system design advantages, which are discussed in the paper, as well as the potential application of these concepts to the exploration of other solar system bodies.