|
SSMIS
The Special Sensor Microwave Imager / Sounder (SSMIS) is a 24-channel, 21-frequency, linearly polarized passive microwave radiometer system. The instrument is flown on board the United States Air Force Defense Meteorological Satellite Program (DMSP) F-16, F-17, F-18 and F-19 satellites, which were launched in October 2003, November 2006, October 2009, and April 2014, respectively. It is the successor to the Special Sensor Microwave/Imager The Special Sensor Microwave/Imager (SSM/I) is a seven-channel, four-frequency, linearly polarized passive microwave radiometer system.Hollinger, J.P. 1989: ''DMSP Special Sensor Microwave/Imager Calibration/Validation''. Final Report, Vol. I., Spac ... (SSM/I). The SSMIS on the F19 satellite stopped producing useful data in February 2016. Instrument characteristics The SSMIS sensor is a passive conically scanning microwave radiometer that combines and extends the current imaging and sounding capabilities of three previously separate DMSP mi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Special Sensor Microwave/Imager
The Special Sensor Microwave/Imager (SSM/I) is a seven-channel, four-frequency, linearly polarized passive microwave radiometer system.Hollinger, J.P. 1989: ''DMSP Special Sensor Microwave/Imager Calibration/Validation''. Final Report, Vol. I., Space Sensing Branch, Naval Research Laboratory, Washington D.C. It is flown on board the United States Air Force Defense Meteorological Satellite Program (DMSP) Block 5D-2 satellites. The instrument measures surface/atmospheric microwave brightness temperatures (TBs) at 19.35, 22.235, 37.0 and 85.5 GHz. The four frequencies are sampled in both horizontal and vertical polarizations, except the 22 GHz which is sampled in the vertical only. The SSM/I has been a very successful instrument, superseding the across-track and Dicke radiometer designs of previous systems. Its combination of constant-angle rotary-scanning and total power radiometer design has become standard for passive microwave imagers, e.g. TRMM Microwave Imager, AMSR. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microwave Radiometer
A microwave radiometer (MWR) is a radiometer that measures energy emitted at one millimeter-to-metre wavelengths (frequencies of 0.3–300 GHz) known as microwaves. Microwave radiometers are very sensitive receivers designed to measure thermally-emitted electromagnetic radiation. They are usually equipped with multiple receiving channels to derive the characteristic emission spectrum of planetary atmospheres, surfaces or extraterrestrial objects. Microwave radiometers are utilized in a variety of environmental and engineering applications, including remote sensing, weather forecasting, climate monitoring, radio astronomy and radio propagation studies. Using the microwave spectral range between 1 and 300 GHz provides complementary information to the visible and infrared spectral range. Most importantly, the atmosphere and also vegetation is semi-transparent in the microwave spectral range. This means its components like dry gases, water vapor, or hydrometeors interact with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States Air Force
The United States Air Force (USAF) is the air service branch of the United States Armed Forces, and is one of the eight uniformed services of the United States. Originally created on 1 August 1907, as a part of the United States Army Signal Corps, the USAF was established as a separate branch of the United States Armed Forces in 1947 with the enactment of the National Security Act of 1947. It is the second youngest branch of the United States Armed Forces and the fourth in order of precedence. The United States Air Force articulates its core missions as air supremacy, global integrated intelligence, surveillance and reconnaissance, rapid global mobility, global strike, and command and control. The United States Air Force is a military service branch organized within the Department of the Air Force, one of the three military departments of the Department of Defense. The Air Force through the Department of the Air Force is headed by the civilian Secretary of the Ai ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Defense Meteorological Satellite Program
The Defense Meteorological Satellite Program (DMSP) monitors meteorological, oceanographic, and solar-terrestrial physics for the United States Department of Defense. The program is managed by the United States Space Force with on-orbit operations provided by the National Oceanic and Atmospheric Administration (NOAA). The (originally classified) mission of the satellites was revealed in March 1973. They provide cloud cover imagery from polar orbits that are Sun-synchronous at nominal altitude of . History During the 1960s, one of the most important projects that the United States civil space program was involved in dealt with meteorology and weather forecasting. Unbeknownst to many, the U.S. military services were also starting up a weather satellite program. This program, the DMSP, would relay important weather and climate data to the military for more effective operations. From the onset of the DMSP program, knowledge of its existence was limited to "need-to-know" personne ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Space
Space is the boundless three-dimensional extent in which objects and events have relative position and direction. In classical physics, physical space is often conceived in three linear dimensions, although modern physicists usually consider it, with time, to be part of a boundless four-dimensional continuum known as spacetime. The concept of space is considered to be of fundamental importance to an understanding of the physical universe. However, disagreement continues between philosophers over whether it is itself an entity, a relationship between entities, or part of a conceptual framework. Debates concerning the nature, essence and the mode of existence of space date back to antiquity; namely, to treatises like the '' Timaeus'' of Plato, or Socrates in his reflections on what the Greeks called ''khôra'' (i.e. "space"), or in the ''Physics'' of Aristotle (Book IV, Delta) in the definition of ''topos'' (i.e. place), or in the later "geometrical conception of plac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microwave Technology
Microwave is a form of electromagnetic radiation with wavelengths ranging from about one meter to one millimeter corresponding to frequencies between 300 MHz and 300 GHz respectively. Different sources define different frequency ranges as microwaves; the above broad definition includes both UHF and EHF ( millimeter wave) bands. A more common definition in radio-frequency engineering is the range between 1 and 100 GHz (wavelengths between 0.3 m and 3 mm). In all cases, microwaves include the entire SHF band (3 to 30 GHz, or 10 to 1 cm) at minimum. Frequencies in the microwave range are often referred to by their IEEE radar band designations: S, C, X, Ku, K, or Ka band, or by similar NATO or EU designations. The prefix ' in ''microwave'' is not meant to suggest a wavelength in the micrometer range. Rather, it indicates that microwaves are "small" (having shorter wavelengths), compared to the radio waves used prior to microwave ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Satellite Meteorology
A weather satellite or meteorological satellite is a type of Earth observation satellite that is primarily used to monitor the weather and climate of the Earth. Satellites can be polar orbiting (covering the entire Earth asynchronously), or geostationary (hovering over the same spot on the equator). While primarily used to detect the development and movement of storm systems and other cloud patterns, meteorological satellites can also detect other phenomena such as city lights, fires, effects of pollution, auroras, sand and dust storms, snow cover, ice mapping, boundaries of ocean currents, and energy flows. Other types of environmental information are collected using weather satellites. Weather satellite images helped in monitoring the volcanic ash cloud from Mount St. Helens and activity from other volcanoes such as Mount Etna. Smoke from fires in the western United States such as Colorado and Utah have also been monitored. El Niño and its effects on weather are monitored da ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radiometry
Radiometry is a set of techniques for measuring electromagnetic radiation, including visible light. Radiometric techniques in optics characterize the distribution of the radiation's power in space, as opposed to photometric techniques, which characterize the light's interaction with the human eye. The fundamental difference between radiometry and photometry is that radiometry gives the entire optical radiation spectrum, while photometry is limited to the visible spectrum. Radiometry is distinct from quantum techniques such as photon counting. The use of radiometers to determine the temperature of objects and gasses by measuring radiation flux is called pyrometry. Handheld pyrometer devices are often marketed as infrared thermometers. Radiometry is important in astronomy, especially radio astronomy, and plays a significant role in Earth remote sensing. The measurement techniques categorized as ''radiometry'' in optics are called ''photometry'' in some astronomical applicati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
