Solar sail technology—A state of the art review

Schemes have been suggested for transferring energy from Earth-to-space, space-to-Earth, and space-to-space using high-power microwave (HPM) beams. All use power beaming. Microwave beams have been studied for propelling spacecraft for launch to orbit, orbit raising, launch from orbit into interplanetary and interstellar space, and deployment of large space structures. The microwave thermal rocket, called the ldquomicrowave thermal thruster,rdquo is a reusable single-stage vehicle that uses an HPM beam to provide power to a heat-exchanger propulsion system, with double the specific impulse of conventional rockets. Orbital missions include orbit raising and space solar power. Microwave-propelled sails are a new class of spacecraft that promises to revolutionize future space probes. Experiments and simulations have verified that sails riding beams can be stable on the beam for conical sail shapes. Beam-driven sail flights have now demonstrated the basic features of the beam-driven propulsion. Beams can also carry angular momentum and communicate it to a sail to help control it in flight. An early mission for microwave space propulsion is dramatically shortening the time needed for sails to escape Earth's orbit. A number of missions for beam-driven sails have been quantified for high-velocity mapping of the outer solar system, Kuiper Belt, the Heliopause, and the penultimate interstellar precursor mission. For large HPM systems at fixed effective isotropic radiated power, minimum capital cost is achieved when the cost is equally divided between antenna gain and radiated power. This is a driver when considering design of power-beaming systems such as interstellar Beacons, which the Search for Extraterrestrial Intelligence is searching for. Much of the technical means for these applications are already in hand. Microwave and millimeter-wave array antennas are already in use for astronomy; sources at high frequencies are being developed for fusion and the military. Development of high-power arrays is needed. A synergistic way to develop a space power-beaming infrastructure is incremental buildup, addressing lower power applications first, and then upgrading.

Space Applications of High-Power Microwaves

Spectroscopic studies of rhodamine 6G dispersed in polymethylcyanoacrylate

Publisher Summary This chapter discusses the materials for solid-state dye lasers and presents a detailed account of the developments in the field of solid-state dye lasers over the past 15 years. The characteristics, properties, and preparation methods of different materials used as solid hosts for lasing dyes are also considered in the chapter in addition to the structures and photophysical properties of the organic dyes incorporated into solid matrices. The development of solid-state dye lasers with emission in the blue and green spectral regions requires a very careful assessment and optimization of the different parameters involved in the laser operation before performances comparable to those of the more developed solid-state dye lasers with emission at longer wavelengths could be obtained. The technology of solid-state dye lasers has improved a lot over the past decade, and new dyes and hosts with better performances have been developed.

Materials for solid-state dye lasers

The UAH Propulsion Research Center (PRC) is in its 29 year at the University of Alabama in Huntsville (UAH). The mission of the Propulsion Research Center is to provide an environment that connects the academic research community with the needs and concerns of the propulsion community while promoting an interdisciplinary approach to solving propulsion problems. This paper summarizes recent metrics from academic and research programs that are associated with the PRC. The emphasis this year is describing the graduate student production supported by the PRC over the past 29 years. This assessment identified over 270 theses and dissertations into 9 different propulsion categories. The results accumulated into 207 master’s and 67 Ph.D.s with the highest production rate being 21 degrees per year in 2010. The documents are distributed into categories representing conventional propulsion, advanced propulsion, missile design, airbreathing propulsion, Propulsion Testing, and Propulsion Systems Engineering. About 83% of the graduates are estimated to be U.S. citizens and there was a 20% female graduation rate. For the current year the total research expenditures from fifteen different agencies are anticipated to rise to $3.3 million which is a 33% compared to last year. PRC researchers published over 130 papers last year. The UAH student launch team placed 3 in the NASA Student Launch national competition this year. The PRC continues to be a resource to accomplish high-quality research, education, and workforce development in propulsion and energy.

Correction: Propulsion Research and Academic Programs at the University of Alabama in Huntsville - PRC Graduate Student Production History

We report on narrow-linewidth long-pulse laser emission from a
dispersive solid-state dye-laser oscillator. Output energy was
∼0.4 mJ/pulse at laser linewidths of 650 MHz and pulse lengths of
105 ns FWHM. The solid-state gain medium utilized was Rhodamine 6G
dye-doped 2-hydroxyethyl methacrylate:methyl methacrylate.

Long-pulse narrow-linewidth dispersive solid-state dye-laser oscillator

What Are Rockets? The History of Rockets Rockets of the Modern Era Rocket Anatomy and Nomenclature Why Are Rockets Needed? Missions and Payloads Trajectories Orbits Orbit Changes and Maneuvers Ballistic Missile Trajectories How Do Rockets Work? Thrust Specific Impulse Weight Flow Rate Tsiolkovsky's Rocket Equation Staging Rocket Dynamics, Guidance, and Control How Do Rocket Engines Work? The Basic Rocket Engine Thermodynamic Expansion and the Rocket Nozzle Exit Velocity Rocket Engine Area Ratio and Lengths Rocket Engine Design Example Are All Rockets the Same? Solid Rocket Engines Liquid Propellant Rocket Engines Hybrid Rocket Engines Electric Rocket Engines Nuclear Rocket Engines Solar Rocket Engines Photon-Based Engines How Do We Test Rockets? The Systems Engineering Process and Rocket Development Measuring Thrust Pressure Vessel Tests Shake 'n Bake Tests Drop and Landing Tests Environment Tests Destructive Tests Modeling and Simulation Roll-Out Test Flight Tests Are We Thinking Like Rocket Scientists and Engineers? Weather Cocking Fuel Sloshing Propellant Vorticity Tornadoes and Overpasses Flying Foam Debris Monocoque The Space Mission Analysis and Design Process Back to the Moon Suggested Reading for Rocket Scientists and Engineers Index A Chapter Summary and Exercises appear at the end of each chapter.

Introduction to Rocket Science and Engineering

This paper first presents a review of interstellar laser and maser sailing. Concepts for very large space based laser (VLSBL) architectures are discussed, which would be required for interstellar laser sailing. A discussion of the power, optical, and pointing requirements is given as well as a description of a diode based VLSBL architecture. Analysis of state of the art pointing jitter requirements for laser sailing is given. Statistical analysis of the beam angular distribution as a function of time is modeled and incident light pressure on a sail at large distances is calculated. Also given are concepts designs for very large aperture adaptive optics to improve laser sailing efficiency.

Space Based Energy Beaming Requirements for Interstellar Laser Sailing

Real-time liquid crystal television-based technique for simulating optical wavefront distortion due to atmospheric turbulence is presented and demonstrated. A liquid crystal television (LCTV) operating in the “phase mostly” mode was used as an array of spatially correlated phase delays. A movie of the arrays in motion was then generated and displayed on the LCTV. The turbulence simulation system was verified by passing a collimated and doubled diode pumped Nd:YVO4 laser beam (532 nm ) through the transparent LCTV screen. The beam was then passed through a lens and the power spectra of the turbulence information carrying beam was detected as a measure of the far-field distribution. The same collimated laser beam, without the LCTV, was also transmitted down an open-air range and the power spectra detected as a measure of a real far-field distribution. Accepted turbulence parameters were measured for both arrangements and then compared.

Laboratory simulation of atmospheric turbulence-induced optical wavefront distortion

Many comets have perihelions at distances within 1.0 Astronomical Unit (AU) from the sun. These comets typically are inclined out of the ecliptic. We propose that a solar sail spacecraft could be used to increase the inclination of the orbit to match that of these 1.0 AU comets. The solar sail spacecraft would match the orbit velocity for a short period of time, which would be long enough for a container to be injected into the comet's nucleus. The container would be extended from a long durable tether so that the solar sail would not be required to enter into the potentially degrading environment of the comet s atmosphere. Once the container has been filled with sample material, the tether is retracted. The solar sail would then lower its inclination and fly back to Earth for the sample return. In this paper, we describe the selection of cometary targets, the mission design, and the solar sailcraft design suitable for sail-comet rendezvous as well as possible rendezvous scenarios.

/pdf/solar-sail-application-to-comet-nucleus-sample-return-2sigj58z60.pdf

Travis S. Taylor

Papers

Long-pulse narrow-linewidth dispersive solid-state dye-laser oscillator

Introduction to Rocket Science and Engineering

Space Based Energy Beaming Requirements for Interstellar Laser Sailing

Laboratory simulation of atmospheric turbulence-induced optical wavefront distortion

Solar sail application to comet nucleus sample return