THIS PROJECT IS FOCUSED ON THE DESIGN AND DEVELOPMENT OF NEXT GENERATION MINIATURE ELECTROSPRAY DEVICES FOR SPACE APPLICATIONS REQUIRING MICROPROPULSION CAPABILITY. OUR EFFORTS COMBINE THEORETICAL NUMERICAL AND IDEALIZED EXPERIMENTAL STUDIES CONDUCTED ON CAMPUS WITH ACTUAL PROTOTYPE RUNS HEADED BY THE ELECTRIC PROPULSION GROUP AT THE NASA JET PROPULSION LABORATORY IN PASADENA CA. OUR TEAM ANTICIPATES THAT THE FIRST PROTOTYPES WILL BE FLIGHT TESTED IN SPACE WITHIN THREE TO FOUR YEARS. ELECTROSPRAY PROPULSION RELIES ON A WELL-KNOWN ELECTROHYDRODYNAMIC PHENOMENON WHEREBY A THIN FILM OF CONDUCTIVE FLUID IS SPONTANEOUSLY DEFORMED INTO ONE OR MANY SHARP CONE-LIKE PROTRUSIONS CALLED TAYLOR CONES. THESE CONES FORM WHEN THE LIQUID IS SUBJECTED TO VERY LARGE ELECTRIC FIELD STRENGTHS SUCH THAT THE MAXWELL FORCES OVERCOME THE RESTORING FORCE OF SURFACE TENSION. FOR LIQUID METAL PROPELLANTS THE SURFACE TENSION IS AN ORDER OF MAGNITUDE LARGER THAN ORDINARY LIQUIDS WHICH IN TURN REQUIRES APPLICATION OF LARGE FIELD STRENGTHS. THESE TAYLOR CONES REPRESENT HIGHLY UNSTABLE CONFIGURATIONS WHICH RAPIDLY TRANSITION INTO NEEDLE LIKE JETS EMITTED FROM THE CONE APICES. THESE NANOSCALE DIAMETER STREAMS PRODUCED SPRAYS THAT CONTAIN CHARGE DROPLETS CHARGED IONS OR BOTH DEPENDING ON THE FIELD STRENGTH AND DIRECTION ELECTRODE AND CAPILLARY GEOMETRY AND PROPERTIES OF THE LIQUID PROPELLANT. ADDITIONAL FOCUSING ELEMENTS ARE OFTEN REQUIRED TO CONVERT ELECTROSPRAYS INTO HIGHLY DIRECTIONAL BEAMS. COLLIMATED BEAMS OF CHARGED IONS PRODUCED FROM THE TIPS OF MICROCAPILLARY TUBES ARE CURRENTLY USED IN CONVENTIONAL ELECTROSPRAY APPLICATIONS SUCH AS FOCUSED ION BEAMS FOR DIRECT WRITE PATTERNING. THESE BEAMS ABLATE MATERIAL SELECTIVELY ACCORDING TO PRESCRIBED PATTERNS AND ARE COMMONLY USED FOR FABRICATING HIGH RESOLUTION LITHOGRAPHIC MASKS. ELECTROSPRAYS ALSO ALSO USEFUL FOR MASS SPECTROMETRY IN IDENTIFYING VARIOUS COMPOUNDS OR SPECIES THROUGH MEASUREMENT OF CHARGE TO MASS RATIOS. OUR TEAM IS DEVELOPING ANALOGOUS BUT HIGHLY MINIATURIZED SYSTEMS FOR SPACE MICROPROPULSION APPLICATIONS WHICH WILL ALLOW SITE SPECIFIC EMISSION AND THRUST. TO FURTHER THIS GOAL OF PROPULSION ON A CHIP WE ARE INCORPORATING AND ADVANCING RECENT DEVELOPMENTS IN MICROFLUIDIC NETWORK ARRAYS AND NOVEL SILICON MICROFABRICATION TECHNIQUES. ELECTROSPRAY BASED PROPULSION IS A VERY ATTRACTIVE ALTERNATIVE TO CONVENTIONAL PROPULSION PLATFORMS FOR SEVERAL REASONS. FIRST OPERATION IS BASED ON AN IDEAL COMBINATION OF CAPILLARY AND ELECTROHYDRODYNAMIC FLOW WHICH CAN BE PRECISELY AND DIGITALLY CONTROLLED. THE DESIGN LAYOUT ALSO ALLOWS EASY SCALE UP/DOWN OF THRUST LEVELS UNLIKE CONVENTIONAL CHEMICAL OR HALL THRUSTER SYSTEMS. SECONDLY MINIATURE THRUSTERS MICROARRAYS CAN BE MADE TO DELIVER PRECISE THRUST WITH CONSEQUENT HIGH RESOLUTION DUE TO THE SMALL MASS OF EMITTED IONS OR DROPLETS AND THE COMPACT NATURE OF THE EMISSION LAYOUT. FINALLY HIGHER EXHAUST VELOCITIES CAN BE ATTAINED. EXHAUST VELOCITY IS PROPORTIONAL TO SPECIFIC IMPULSE WHICH ESTABLISHES THE FUEL CONSUMPTION RATE REQUIRED FOR GIVEN THRUST. IN CONTRAST TO CHEMICALLY REACTING SYSTEMS WHERE THE EXHAUST VELOCITY OF THE PROPELLANT FLUID IS LIMITED BY THE SPECIFIC ENERGY RELEASED BY THE REACTION ELECTROSPRAY GENERATED STREAMS CAN BE ACCELERATED TO ARBITRARILY HIGH SPEEDS BY INCLUSION OF DOWNSTREAM ACCELERATING PLATES WHICH ALSO HELP MAINTAIN GOOD COLLIMATION. ELECTROSPRAY EXHAUST VELOCITIES CAN THEREFORE EASILY SURPASS THOSE OF CHEMICAL THRUSTERS BY AN ORDER OF MAGNITUDE. THESE ADVANTAGEOUS ATTRIBUTES OF SCALABILITY PRECISION EMISSION LOW MASS AND ADDITIVE THRUST BASED ON COMPACT MICROARRAY LAYOUTS SUGGEST A TECHNOLOGY IDEALLY SUITED TO CONTROL OF CUBESATS AND OTHER SMALL SATELLITE SYSTEMS. ULTIMATELY FINER CONTROL OVER DEPLOYMENT AND FLYING FORMATIONS WILL TRANSLATE INTO LOWER COSTS YET DENSER COVERAGE FOR DISTRIBUTED SATELLITE NETWORKS.