Search NASA⌕ Search

SEARCH · Search NASA

Results for “METEOROLOGICAL SATELLITES”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 181 records · Page 10

Task 2: Flight prototype system design report, pulsed plasma solid propellant microthruster for the Synchronous Meteorological Satellite

Design details are presented of the solid propellant pulsed plasma microthruster which was analyzed during the Task 1 effort. The design details presented show that the inherent functional simplicity underlying the flight proven LES-6 design can be maintained in the SMS systems design even with minimum weight constraints imposed. A 1293 hour uninterrupted vacuum test with the engineering thermal model, simulating an 18.8 to 33 g environment of the propellant, its feed system and electrode assembly, revealed that program thruster performance requirements could be met. This latter g environment is a more severe environment than will be ever encountered in the SMS spacecraft.

Guman, W. J.↗

Pulsed plasma solid propellant microthruster for the synchronous meteorological satellite. Task 4: Engineering model fabrication and test report

Two flight prototype solid propellant pulsed plasma microthruster propulsion systems for the SMS satellite were fabricated, assembled and tested. The propulsion system is a completely self contained system requiring only three electrical inputs to operate: a 29.4 volt power source, a 28 volt enable signal and a 50 millsec long command fire signal that can be applied at any rate from 50 ppm to 110 ppm. The thrust level can be varied over a range 2.2 to 1 at constant impulse bit amplitude. By controlling the duration of the 28 volt enable either steady state thrust or a series of discrete impulse bits can be generated. A new technique of capacitor charging was implemented to reduce high voltage stress on energy storage capacitors.

Guman, W. J.↗

Use of meteorological satellite observations in weather modification programs

The potential value of weather satellite data in field operations of weather modification is appraised. It was found that satellites could play a useful role in operational weather modification projects, particularly in the recognition of treatment opportunities. Satellite cloud photographs and infrared observations appear promising in the identification of treatment opportunities in seeding orographic cloud systems for increased snowpack, in seeding convective clouds for increased rainfall, in identifying hail threats, and in tracking and observing hurricanes as an aid to timing and location of seeding treatments. It was concluded that the potential value of satellite data in the treatment and evaluation phases of operational projects is not as great as in the recognition of treatment opportunity.

Dennis, A. S.↗

The synchronous meteorological satellite /SMS/ system.

The responsibilities of the National Aeronautics and Space Administration (NASA) and Department of Commerce (DOC) pertaining to SMS are described in this paper. A description of the program objectives, payload, and spacecraft subsystems, is included along with an abbreviated description of the SMS ground system. Particular interest is directed towards the visible and infrared spin-scan radiometer (VISSR) as it will be the prime sensor and its performance directly effect the mission objectives. Also, of significant importance is the description of the communications subsystem since transmission and retransmission of image data, data relay, and data collection platform (DCP) transmissions play such a major role in the system. The conclusion is established that the current plans form a workable system for providing timely, high-quality day and night imaging of the earth's weather.

Burr, P. T.↗

Pulsed plasma microthruster for synchronous meteorological satellite /SMS/

Two completely self contained variable thrust flight prototype plasma propulsion systems using solid teflon as propellant were designed, built and laboratory tested. The impulse bit amplitude of each thruster is 25 micro lb-sec. Impulse bits can be provided at rates varying from 50 ppm to 110 ppm. The total impulse capability is 400 lb-sec. Only 23 watts of bus power are required at maximum pulse rate. The system was subjected and passed the required vibration schedule and thermal vacuum test after a minor change in capacitor end face material. A 13 million discharge life test of the system was subsequently performed.

Guman, W. J.↗

Microwave spectrometer on the Nimbus 5 satellite - Meteorological and geophysical data

The Nimbus 5 microwave spectrometer has been used to measure thermal radiation in five frequency bands between 22.235 and 58.8 gigahertz, and has yielded both the temperature profile and, over ocean, the vapor and liquid water content of the terrestrial atmosphere, even in overcast conditions. Information has also been obtained on geophysical parameters that affect the surface emissivity, such as ice type, sea roughness, and snow cover. The experiment demonstrates the considerable potential of passive microwave sensing of meteorological and geophysical parameters.

Staelin, D. H.↗

Synchronous meteorological satellite spin testing

The objective of the end-to-end spin test is to demonstrate both qualitatively and quantitatively that the satellite performs its intended functions under spinning conditions. The test is performed twice per satellite, once during the baseline functional test prior to environmental testing, and once during the final functional test. All satellite functions are demonstrated during the spin test with the exception of solar panel illumination, pyrotechnic device operation, VISSR infrared operation, and auxiliary propulsion system operation.

Mcbrady, D. J.↗