Methods of Higher Alcohol Synthesis
Systems, catalysts, and methods are provided for transforming carbon based material into synthetic mixed alcohol fuel.
White, Emily B.↗
Engineering topics
Zubrin, Robert M.
Publications and source records attributed to Zubrin, Robert M..
New vision solar system mission study: Use of space reactor bimodal system with microspacecraft to determine origin and evolution of the outer plants in the solar system
The vision for the future of the planetary exploration program includes the capability to deliver 'constellations' or 'fleets' of microspacecraft to a planetary destination. These fleets will act in a coordinated manner to gather science data from a variety of locations on or around the target body, thus providing detailed, global coverage without requiring development of a single large, complex and costly spacecraft. Such constellations of spacecraft, coupled with advanced information processing and visualization techniques and high-rate communications, could provide the basis for development of a 'virtual presence' in the solar system. A goal could be the near real-time delivery of planetary images and video to a wide variety of users in the general public and the science community. This will be a major step in making the solar system accessible to the public and will help make solar system exploration a part of the human experience on Earth.
Mondt, Jack F.↗
Practical methods for near-term piloted Mars missions
An evaluation is made of ways of using near-term technologies for direct and semidirect manned Mars missions. A notable feature of the present schemes is the in situ propellant production of CH4/O2 and H2O on the Martian surface in order to reduce surface consumable and return propellant requirements. Medium-energy conjunction class trajectories are shown to be optimal for such missions. Attention is given to the backup plans and abort philosophy of these missions. Either the Russian Energia B or U.S. Saturn VII launch vehicles may be used.
Zubrin, Robert M.↗
The use of low power dual mode nuclear thermal rocket engines to support space exploration missions
The evolution of dual mode concepts is presented, focusing on advantages and problems associated with both low and high temperature dual mode conversion systems. It is concluded that dual mode nuclear thermal rocket (NTR) systems using high temperature Brayton cycle conversion technology offer a high payoff enhancement of conventional NTR, with a comparatively minor increase of technological challenge. It is recommended that NTR engines be designed so that dual mode conversion systems can be attached to them in a modular way, thus enabling the production of electric power on all missions where it is needed.
Zubrin, Robert M.↗
Mars direct - A coherent architecture for the Space Exploration Initiative
The coherency of the conventional earth-orbital assembly/Mars orbital rendezvous is analyzed in terms of the Space Exploration Initiative (SEI) architecture and an alternate approach is given. The coherency - defined as a combination of simplicity, robustness, and cost-effectiveness - of the conventional SEI is found to be inadequate. The Mars Direct plan is described in detail and proposed as an efficient alternative for both Martian and lunar applications. In situ propellant production on the target-planet's surface is described, and candidate vehicle designs are set forth. Objectives and problems associated with a manned mission are outlined, and details regarding surface activities and support are given. Nuclear thermal rocket propulsion is determined to be an efficient way to improve mission capability, and the Mars Direct SEI architecture can integrate such technology. The Mars Direct SEI is concluded to be a more effective plan than the conventional rendezvous mission.
Zubrin, Robert M.↗
Mars direct - A simple, robust, and cost effective architecture for the Space Exploration Initiative
Both the Martian and lunar forms of implementation of the Mars Direct architecture are discussed. Candidate vehicle designs are presented and the means of performing the required in situ propellant production is explained. The in situ propellant process is also shown to present very high leverage for a Mars Rover Sample Return mission flown as a scaled down precursor version of the manned Mars Direct. Methods of coping with the radiation and zero gravity problems presented by a manned Mars mission are discussed. Prime objectives for surface exploration are outlined and the need for substantial surface mobility is made clear. Combustion powered vehicles utilizing the in situ produced methane/oxygen are proposed as a means for meeting the surface mobility requirement. Nuclear thermal rocket propulsion is suggested as a means to improve mission capability.
Zubrin, Robert M.↗
The engineering of a nuclear thermal landing and ascent vehicle utilizing indigenous Martian propellant
The following paper reports on a design study of a novel space transportation concept known as a 'NIMF' (Nuclear rocket using Indigenous Martian Fuel). The NIMF is a ballistic vehicle which obtains its propellant out of the Martian air by compression and liquefaction of atmospheric CO2. This propellant is subsequently used to generate rocket thrust at a specific impulse of 264 s by being heated to high temperature (2800 K) gas in the NIMFs' nuclear thermal rocket engines. The vehicle is designed to provide surface to orbit and surface to surface transportation, as well as housing, for a crew of three astronauts. It is capable of refueling itself for a flight to its maximum orbit in less than 50 days. The ballistic NIMF has a mass of 44.7 tonnes and, with the assumed 2800 K propellant temperature, is capable of attaining highly energetic (250 km by 34,000 km elliptical) orbits. This allows it to rendezvous with interplanetary transfer vehicles which are only very loosely bound into orbit around Mars. If a propellant temperature of 2000 K is assumed, then low Mars orbit can be attained; while if 3100 K is assumed, then the ballistic NIMF is capable of injecting itself onto a minimum energy transfer orbit to Earth in a direct ascent from the Martian surface.
Zubrin, Robert M.↗
The engineering of a nuclear thermal landing and ascent vehicle utilizing indigenous Martian propellant
A design study of a novel space transportation concept called NIMF (Nuclear rocket using Indigenous Martian Fuel) is reported. In this concept, Martian CO2 gas, which constitutes 95 percent of the atmosphere, is liquified by simple compression to about 100 psi and remains stable without refrigeration. When heated and exhausted out of a rocket nozzle, a specific impulse of about 264 s can be achieved, sufficient for flights from the surface to highly energetic orbits or from one point on the surface to any other point. The propellant acquisition system can travel with the vehicle, allowing it to refuel itself each time it lands. The concept offers unequalled potential to achieve planetwide mobility, allowing complete global access for the exploration of Mars. By eliminating the necessity of transporting ascent propellant to Mars, the NIMF can also significantly reduce the initial mass in LEO and of a manned Mars mission.
Zubrin, Robert M.↗
Nuclear thermal rockets using indigenous extraterrestrial propellants
A preliminary examination of a concept for a Mars and outer solar system exploratory vehicle is presented. Propulsion is provided by utilizing a nuclear thermal reactor to heat a propellant volatile indigenous to the destination world to form a high thrust rocket exhaust. Candidate propellants, whose performance, materials compatibility, and ease of acquisition are examined and include carbon dioxide, water, methane, nitrogen, carbon monoxide, and argon. Ballistics and winged supersonic configurations are discussed. It is shown that the use of this method of propulsion potentially offers high payoff to a manned Mars mission. This is accomplished by sharply reducing the initial mission mass required in low earth orbit, and by providing Mars explorers with greatly enhanced mobility in traveling about the planet through the use of a vehicle that can refuel itself each time it lands. Thus, the nuclear landing craft is utilized in combination with a hydrogen-fueled nuclear-thermal interplanetary launch. By utilizing such a system in the outer solar system, a low level aerial reconnaissance of Titan combined with a multiple sample return from nearly every satellite of Saturn can be accomplished in a single launch of a Titan 4 or the Space Transportation System (STS). Similarly a multiple sample return from Callisto, Ganymede, and Europa can also be accomplished in one launch of a Titan 4 or the STS.
Zubrin, Robert M.↗
Use of magnetic sails for advanced exploration missions
The magnetic sail, or magsail, is a field effect device which interacts with the ambient solar wind or interstellar medium over a considerable volume of space to generate drag and lift forces. Two theories describing the method of thrust generation are analyzed and data results are presented. The techniques for maintaining superconductor temperatures in interplanetary space are analyzed and low risk options presented. Comparisons are presented showing mission performance differences between currently proposed spacecraft using chemical and electric propulsion systems, and a Magsail propelled spacecraft capable of generating an average thrust of 250 Newtons at a radius of one A.U. The magsail also provides unique capabilities for interstellar missions, in that at relativistic speeds the magnetic field would ionize and deflect the interstellar medium producing a large drag force. This would make it an ideal brake for decelerating a spacecraft from relativistic speeds and then maneuvering within the target star system.
Andrews, Dana G.↗