Propulsion satellites

The lithium-vanadium pentoxide solid state battery, designed with applications in vehicle propulsion, satellite power and portable equipment in mind, is being developed by Harwell UK Ltd, the former British Atomic Energy Research Establishment. 

Energy systems in space technology are devices that convert one kind of energy into another to ensure the functioning of automated and piloted satellites, interplanetary probes, and other kinds of spacecraft. Multiple functions of any spacecraft require two distinctly different energy sources propulsion for launch and maneuvers, and electricity supply to power the onboard equipment. 

The first experiments with the thermal electric engine were conducted in Russia in 1929 by its inventor, Valentin P. Glushko, who later became a world-famous authority in rocket propulsion. For more than forty years, the United States and Russia have devoted many resources to research and development of various kinds of EREs. First tested in space by the Russians in 1964, these engines have found some limited applications in modern space technology. For more than two decades Russian weather and communication satellites have regularly used electric rocket engines for orbital stabilization. The first spacecraft to employ ERE for main propulsion was the American asteroid exploration probe Deep Space 1, launched in 1998. The performance of... 

Spacecraft and satellite power, spacecraft propulsion, research and special materials production... 

F.J.M., and Zevenbergen, J. (2004) Technology status of HNF based monopropellants for satellite propulsion. Proc. 2nd Ind Conf. on Green Propellants for Space Propulsion, Cagliari, Sardinia, Italy, June 07-08,... 

The Jet Propulsion Laboratory (JPL) research team have successfully flown the Microwave Limb Sounder (MLS) aboard the Upper Atmospheric Research Satellite (UARS), which has been measuring stratospheric profiles of CIO, O3, H20 and HN03 since 1992 (Waters et al., 1993) (Table 1). In total some 140 publications have been published on the basis of MLS data. The Microwave Atmospheric Sounder (MAS) flew three times aboard the Shuttle also measuring CIO, 03 and H20 and has also provided a unique set of observations (Hartmann et al., 1996). 

After hydrogen inflated balloons, this was another revolution in the field of transportation afforded by hydrogen. Liquid propulsion was instrumental in enabling the race to the moon that led the astronaut Neil Armstrong to walk on our satellite on 21 July 1968 with the Apollo XI mission. 

This book is concerned with both the civil applications of high-energy materials (e.g. propellants for carrier or satellite launch rockets and satellite propulsion systems) as well as the many military aspects. In the latter area there have been many challenges for energetic materials scientists in recent days some of which are listed below ... 

The first laboratory quality observations made from balloon platforms were middle infrared absorption experiments of trace atmospheric spedes using the sun as a source. This work has now been extended to shuttle and satellite-based observations using Fourier interferometers. The ATMOS instrument, developed under the leadership of C.B. Farmer and the NASA Jet Propulsion Laboratory, represents the flagship of this ef-... 

Space technology often uses alloys that are too expensive for everyday use. An example is the propulsion systems used for keeping satellites in place. Some of these systems use alloys made of iridium and another platinum metal, rhenium. These alloys remain strong at high temperatures and are not attacked by fuels used in the systems. 

Source Adapted from John S. Lewis. Physics and Chemistry of the Solar System, Revised Edition. San Diego Academic Press, 1997, Table VI11.4, page 361. This taxonomy was originally suggested by Edward Tedesco and his colleagues at the Jet Propulsion Laboratory, based on data collected from the IRAS [Infrared Astronomical Satellite] Minor Planet Survey ("AThree-Parameter Asteroid Taxonomy," The Astronomical Journal 97, 580). 

Moreover, there is a current need of miniaturized propulsion system for widening the capabilities of low cost micro-satellites. Recently, the development of a turbo-pump fed miniature rocket engine has been proposed as a new propulsion system for micro-satellites (10 to 100 kg) [6] the bipropellant tlmister uses 70 wt.-% H2O2 as oxidizer and ethanol as fuel. The engine displays four sub-components (i) two propellant micro-pumps, (ii) a HP decomposition chamber, (iii) a turbine coupled to an electric power generator and driven by the hot gas released from HP decomposition, and (iv) a thruster for the combustion reaction. 

FIGURE 2.6 Stratospheric ozone profile over Northern Hemisphere midlatitude (35CN) in September 1996 as measured by satellite with the Jet Propulsion Laboratory FTIR (Fourier transform infrared) spectrometer. Note that molecular concentration and mixing ratio peak at different altitudes. 

A potential application of polymer laser ablation concerns the propulsion of small satellites (1-10 kg) used in space science [86]. Laser plasma thrusters, LPTs, operating with small, powerful diode lasers emitting in the near-infrared wavelength range (930-980 nm) have been proposed. Polymers intended to serve as fuel for a thruster are required to possess a large momentum coupling coefficient, C, defined by Eq. (9-3) ... 

It was mentioned earlier that high-precision nano pressure sensors dispersed in the surface material of a spacecraft could continuously measure the instantaneous drag forces on a satellite. This would, for exanqile, enable real-time propulsion adjustments for high-precision orbit trajectories (drag-fr orbits), a crucial element of satellite formation flying. The ever more frequent discoveries of novel nanoelectronic devices (18) and first denmnstrations thereof as chemical sensors (27) su t that such devices will also play a role in future hyperthermal particle sensing. 

Why do scientists wony about units The National Aeronautics and Space Administration (NASA) recently was reminded of just why keeping track of units is so important. In 1999 a 125 million satellite was lost in the atmosphere of Mars because scientists made some improper assumptions about units. NASA s scientists at the Jet Propulsion Lab (JPL) in Pasadena, California, received thrust data from the satellite s manufacturer, Lockheed Martin Aeronautics in Denver, Colorado. Unfortunately, the Denver scientists used American units in their measurements and the JPL scientists assumed the units were metric. This mistake caused the sateUite to fall 100 km lower into the Mars atmosphere than planned. The spacecraft burned up from the friction with the atmosphere. 

Andreev PV, Galkin AYa, Zhabotinsky EE et al (1995) Electrical propulsion units based on Topaz-type thermionic nuclear power systems for information satellite systems. In Proceedings of the 12th Symposium on space nuclear power systems, Pt. 1, Albuquerque NM, pp 335—339... 

Honowalt, "Skin Temperatures of a Satellite," Jet Propulsion, VoL27, No. 10... 

Like all high-performance systems, propulsion systems often push the edge of stable operation. Some descriptive terms include the pogo instability of rockets, the screech instability of jet engines, the supersonic inlet buzz, compressor surge, and sloshing in satellite fuel tanks. 

---