- Ionosphere
The ionosphere IPAc en icon a n s f r is a part of the upper Earth s atmosphere atmosphere ... name rawer K. Rawer. Wave Propagation in the Ionosphere . Kluwer Acad.Publ., Dordrecht 1993. ISBN ... and ionosphere Geophysics The ionosphere is a shell of electrons and electrically charged atom s and molecule ... which is referred to as the ionosphere. In a plasma, the negative free electrons and the positive ... . The amount of ionization in the ionosphere varies greatly with the amount of radiation received ..., and equatorial regions . There are also mechanisms that disturb the ionosphere and decrease the ionization ... layers File Ionosphere Layers en.svg thumb 250px Ionospheric layers. At night the F layer is the only ... than 500 km above the surface of Earth. It is the densest point of the ionosphere, which implies ... ionosphere . Here extreme ultraviolet UV, 10 100 nm solar radiation ionizes atomic oxygen . The F ... ref Ionospheric model An ionospheric model is a mathematical description of the ionosphere as a function ... is the International Reference Ionosphere IRI ref D.Bilitza International Reference Ionosphere ... modelweb ionos iri.html title International Reference Ionosphere publisher Ccmc.gsfc.nasa.gov ... bottom of the ionosphere to the altitude of maximum density than in describing the total electron content TEC .Since 1999 this model is International Standard for the terrestrial ionosphere standard ... anomaly Image Diurnal ionospheric current.jpg frame right Electric currents created in sunward ionosphere ... ionosphere move plasma up and across the magnetic field lines. This sets up a sheet of electric ... called Sq solar quiet current system in the E region of the Earth s ionosphere 100 130 km ... day side of the ionosphere. At the magnetic dip equator, where the geomagnetic field is horizontal ... waves can interact with radiation belt particles and cause them to precipitate onto the ionosphere ... from clouds to the ionosphere. Around the same time, Robert Watson Watt, working at the Radio Research ... more details
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- Ionosphere Bay
Orphan date February 2009 Ionosphere Bay is a small headlands and bays bay bordering the east side of Cape Decouverte . Charted in 1951 by the French Antarctic Expedition and named by them for the corresponding scientific discipline. coord 66 46 S 141 35 E display title usgs gazetteer Category Bays of Ad lie Land Ad lieLand geo stub ... more details
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- Earth?ionosphere waveguide
The Earth ionosphere waveguide refers to the phenomenon in which certain Radio propagation radio waves can propagate in the space between the ground and the boundary of the ionosphere . Because the ionosphere contains charged particles , it can behave as a Electrical conductor conductor . The earth operates as a ground plane , and the resulting cavity behaves as a large waveguide . Extremely low frequency ELF and Very low frequency VLF 300 Hertz Hz 30 kHz frequency signals can propagate efficiently in this waveguide. For instance, lightning strikes launch a signal called radio atmospherics , which can travel many thousands of miles, because they are confined between the Earth and ionosphere. The round the world nature of the waveguide produces resonance s, like a cavity, which are at 7 Hz. See also Radio propagation Skywave Shortwave radio Tropospheric ducting Atmospheric duct Waveguide radio spectrum DEFAULTSORT Earth Ionosphere Waveguide Category Electromagnetism Category Radio technology Category Radio frequency propagation Telecomm stub physics stub ... more details
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- Ionosphere-Thermosphere Storm Probes
Infobox Spacecraft Name Ionosphere Thermosphere Storm Probes Organization NASA Mission Type Two Earth orbiters investigating the ionosphere and thermosphere Number of Observatories 2 Inclination 60 degrees The Ionosphere Thermosphere Storm Probes I TSP is a NASA mission which will study the ionosphere and the thermosphere . This mission is part of the Living With a Star program, the second mission in a pair of geospace missions. The first mission is the Radiation Belt Storm Probes , which launches in 2012. Mission Like the Radiation Belt Storm Probes , the I TSP will be a twin spacecraft mission. The mission is to study distributions of ionospheric and thermospheric densities, geomagnetic disturbances, and ionospheric irreularities. This mission relates to the Sun and solar flare solar storms in that it studies the effects of solar flare solar storms on geospace. ref Cite web url http books.nap.edu openbook.php?record id 11188&page 25 title Future Directions in Solar and Space Physics work The National Academics Press accessdate 2007 08 14 ref This mission can save astronauts and satellites . Goals The Ionosphere Thermosphere Storm Probes mission has two goals Determine the effects of solar variability on the global scale behavior of ionospheric electron density Determine the solar and geospace causes of small scale ionospheric irregularities See also Ionosphere Radiation Belt Storm Probes Living With a Star Thermosphere References Reflist External links http www.lws.nasa.gov geospace HTML Mission LWSgeospaceITSP.html More Information on Geospace Missions Page http lws.gsfc.nasa.gov Living With a Star page Category NASA programs ... more details
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- International Reference Ionosphere
ref references Literature D.Bilitza 35 years of International Reference Ionosphere... . Adv.in Radio ... et al. International Reference Ionosphere 1978 . International Union of Radio Science ,Brussels 1978 ... more details
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- Dynamic Ionosphere CubeSat Experiment
The Dynamic Ionosphere CubeSat Experiment DICE is a scientific mission consisting of two Miniaturized Satellites DICE 1 and DICE 2 flying in formation. The satellites are an unusual 1.5 U variant of the CubeSat design for microsatellites. Both satellites were launched from Vandenberg Air Force Base in October 2011 atop a Delta II rocket . This was a multi payload mission with four other CubeSats, AubieSat 1 , M Cubed , Explorer 1 and RAX 2 . The satellites are intended to map changes in the Earth s Plasmasphere caused by Geomagnetic storm s. On board control is provided by a Pumpkin FM430 flight control module containing a Texas Instruments MPS430 microcontroller . Communications are provided by a half duplex UHF modem with a 1.5 Mbit s downlink 465 MHz and 19.2 kbit s uplink 450 MHz . The satellites carry four Electric Field Probe sensors on telescopic booms, two DC Langmuir probe s for detection of ions and a three axis magnetometer for measuring magnetic fields . References http space.skyrocket.de doc sdat dice.htm http events.eoportal.org presentations 10003490 10003491.html http pluto.space.swri.edu image glossary plasmasphere2.html Orbital launches in 2011 Category CubeSats ... more details
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- Observatory for Heteroscale Magnetosphere-Ionosphere Coupling
Observatory for Heteroscale Magnetosphere Ionosphere Coupling OHMIC is an explorer program mission consisting of a pair of spacecraft flying in formation studying the energy powering space weather . The principal investigator for the mission is James Burch of the Southwest Research Institute in San Antonio, Texas. ref http www.nasa.gov home hqnews 2011 sep HQ 11 328 Science Proposals.html NASA NASA Selects Science Investigations For Concept Studies Bot generated title ref References reflist explorer program Category Explorer program Category Proposed spacecraft Category 2013 in spaceflight ... more details
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- Constellation Observing System for Meteorology, Ionosphere, and Climate
observation Orbital launches in 2006 DEFAULTSORT Constellation Observing System For Meteorology, Ionosphere ... more details
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- West Ford
Vestfjorden Norway Vestfjord Norwegian fjord Project West Ford a test carried in 1961 and 1963 to create an artificial ionosphere above the Earth disambig ... more details
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- Ground wave propagation
dicdef Radio waves in the vlf Very low frequency band propagate in a ground, or surface wave. the wave is connected at one end to the surface of the earth and to the ionosphere at the other. Category Wave mechanics ... more details
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- Critical frequency
In telecommunication , the term critical frequency has the following meanings In radio radio propagation propagation by way of the ionosphere , the limiting frequency at or below which a wave component is reflected by, and above which it penetrates through, an ionospheric layer. At vertical incidence, the limiting frequency at or below which incidence, the wave component is reflected by, and above which it penetrates through, an ionospheric layer. Critical Frequency changes with time of day, atmospheric conditions and angle of fire of the radio waves by antenna. The existence of the critical frequency is the result of electron limitation, i.e., the inadequacy of the existing number of free electrons to support Reflection electrical reflection at higher frequencies. In signal processing the critical frequency it is also another name for the Nyquist frequency . References FS1037C MS188 Critical frequency is the highest magnitude of frequency above which the waves penetrates the ionosphere and below which the waves are reflected back from the ionosphere. It is denoted by fc . Its value is not fixed and it depends upon electron density of ionosphere. Category Telecommunications telecomm stub ... more details
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- Tiny ionospheric photometer
Unreferenced date February 2007 orphan date November 2009 The tiny ionospheric photometer TIP is a small space based photometer that observes the Earth s ionosphere at 135.6 nm. The TIP instruments were designed and built by the US Naval Research Laboratory and are a part of the Constellation Observing System for Meteorology, Ionosphere, and Climate COSMIC program. Although each TIP instrument is fairly simple in design and operation, the value of this instrument is that six of them are launched at once, and they will observe the earth simultaneously from three orbital planes spaced equally apart around the earth. The data of this instrument when combined with the data from the other COSMIC payloads will allow a 3D tomographic analysis of the Earth s ionosphere to be performed. Category Electromagnetic radiation meters Category Optical devices Optics stub ... more details
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- Skip distance
Multiple issues unreferenced December 2009 orphan October 2009 refimprove October 2009 A skip distance is the distance a radio wave travels, usually including a hop in the ionosphere . A skip distance is a distance on the Earth s surface between the two points where radio waves from a transmitter , refracted downwards by different layers of the ionosphere , fall. It also represents how far a radio wave has travelled per hop on the Earth s surface, for radio waves such as the short wave SW radio signals that employ continuous reflections for transmission. Radio waves from a particular transmitting antenna do not all get refracted by a particular layer of the ionosphere some are absorbed, some refracted while a portion escapes to the next layer. At this higher layer, there is a possibility of this radio wave being bent downwards to earth again. This bending happens because each layer of the ionosphere has a refractive index that varies from that of the others. Because of the differing heights of refraction, or apparent reflection , the radio waves hit the earth surface at different points hence generating the skip distance. Skip distance is greatest during the night when the ionosphere is the highest. See also Maximum usable frequency DEFAULTSORT Skip Distance Category Radio terminology Technology stub ... more details
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- Fukushima's Theorem
In physics , Fukushima s Theorem holds that for all points beneath the ionosphere the magnetic fields from field aligned currents and their corresponding Pederson currents exactly cancel. By superposition the total magnetic field at the ground is then equal to the magnetic field from just the ionospheric Hall currents. Fukushima s Theorem holds in any planar or spherical geometry, provided that the field aligned currents are perpendicular to the ground, and that the ionospheric conductance is spatially constant. Neither of these conditions holds strongly in the auroral region of the Earth s ionosphere. Image Fukushima cancelation.svg thumb Illustration of cancellation of ground magnetic fields by Fukushima s Theorem. Journal articles Naoshi Fukushima , Equivalence in ground geomagnetic effect of Chapman Vestine s and Birkeland Alfven s current systems for polar magnetic storms , Rep. Ionos.Space Res.Jap 23 , 219 227 1969 . Naoshi Fukushima , Generalized theorem for no ground magnetic effect of vertical currents connected with Pedersen currents in the uniform conductivity ionosphere , Rep. Ionos.Space Res.Jap 30 , 35 50 1976 . Naoshi Fukushima , Some topics and historical episodes in geomagnetism and aeronomy , Journal of Geophysical Research 99 , 113 142 1994 . Category Space science ... more details
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- NAIC
NAIC may refer to The National Association of Investors Corporation The National Astronomy and Ionosphere Center The North American Industry Classification System The National Association of Insurance Commissioners The National Air Intelligence Center, a United States Air Force USAF intelligence unit Places Naic, Cavite , Philippines Disambig tl NAIC ... more details
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- Ionex
Ionex is the Russian EDM parts and consumables supply company. http www.ionexedm.ru Ionex , or IONEX, is a name for ion exchange , or for some of the ion exchange resins used for that purpose. IONEX is an ionosphere IONospheric map EXchange ASCII format for two and three dimensional total electron count value maps. disambig ... more details
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- Ionospheric heater
An ionospheric heater is an array of Antenna radio antenna s which are used for heating the ionosphere , and which can create artificial Aurora astronomy aurora Citation needed date March 2010 Or date March 2010 . Current facilities The European Incoherent Scatter Scientific Association EISCAT operates an ionospheric heating facility, capable of transmitting over 1 GW http e7.eiscat.se groups Documentation BasicInfo http www.kurasc.kyoto u.ac.jp s ramp abstract s19.txt effective radiated power ERP , near Troms in Norway . Russia has the Sura Ionospheric Heating Facility Sura ionospheric heating facility , in Vasilsursk near Nizhniy Novgorod , capable of transmitting 190 MW ERP. The United States has three ionospheric heating facilities High Frequency Active Auroral Research Program HAARP 4 GW ERP north of Gakona, Alaska HIPAS Observatory 70 MW ERP northeast of Fairbanks, Alaska Arecibo Observatory in Puerto Rico Peru Jicamarca Radio Observatory Ionosphere modification According to researchers noted in USAF research paper http csat.au.af.mil 2025 volume3 vol3ch15.pdf Weather as a Force Multiplier Owning the Weather in 2025 , ionosphere heating was among techniques investigated by the former Soviet Union to either enhance friendly or disrupt enemy communications by modifying the natural ionosphere. Category Atmospheric sciences climate stub physics stub bg ... more details
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- Ionospheric pierce point
Cleanup date August 2009 Most Global Positioning System s GPS are subjected to errors induced by the ionosphere . Because ionospheric delay affects the speed of microwave signals differently depending on their frequency a characteristic known as Dispersion optics dispersion delays measured on two or more frequency bands can be used to measure dispersion, and this measurement can then be used to estimate the delay at each frequency. see Atmospheric Effects in http www.kowoma.de en gps errors.htm Sources of Errors in GPS The principal source of the dispersion comes from the total electron content TEC in the ionosphere, along the line of sight from the satellite to the receiver. Because it is difficult to measure the TEC along the line of sight, instead a prediction can be made using a simplified model of the ionosphere. This model assumes that the ionosphere is a thin, uniform density shell about the earth, located near the mean altitude of maxium TEC approx. 350 km . Using geometry, a slant intersection with this shell model can be determined and a vertical TEC measurement inferred. The point where the line of sight between the satellite and the ground receiver intersects this shell is called the Ionospheric Pierce Point IPP . References Satellite altimetry and earth sciences , By Lee Leung Fu, Anny Cazenave, page 56. Category GPS ... more details
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- Coherent electromagnetic radio tomography
The Coherent Electromagnetic Radio Tomography CERTO is a radio beacon which measures ionospheric parameters in coordination with ground receivers. CERTO provides global ionospheric maps to aid prediction of radio wave scattering. CERTO was developed by the Naval Research Lab and is one of the 4 experiment packages on PicoSAT satellite. CERTO has near real time measurements of the ionosphere. ref http adsabs.harvard.edu abs 2004AGUSMSA51A..07B Harvard University CERTO Ionosphere Sensing ref Specifications NSSDC ID 2001 043B 01A Mission PicoSAT PicoSAT 9 PicoSAT 9 References Include NASA http nssdc.gsfc.nasa.gov nmc experimentDisplay.do?id 2001 043B 01 NASA Picosat Experiment 2001 43B http www.kirtland.af.mil shared media document AFD 080721 027.pdf Kirtland AFB CERTO reflist Category Earth stations in England Category Satellites Category Artificial satellites orbiting Earth spacecraft stub ... more details
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- Electrojet
of the electrojet. First of all, the conductivity of the auroral ionosphere is generally larger than that at lower latitudes. Secondly, the horizontal electric field in the auroral ionosphere ... www star.stanford.edu vlf ejet electrojet.html Category Atmospheric electricity ionosphere ... more details
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- Ionospheric reflection
Ionospheric reflection is a bending, through a complex process involving Reflection physics reflection and refraction , of electromagnetic waves propagating in the ionosphere back toward the Earth. The amount of bending depends on the extent of penetration which is a function of frequency , the angle of incidence , Polarization waves polarization of the wave, and ionospheric conditions, such as the ionization density. It is negatively affected by incidents of ionospheric absorption . FS1037C Category Radio frequency propagation ... more details
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- Skywave
radio, have taken advantage of skywave for long distance or DX communication . Role of the ionosphere The ionosphere is a region of the upper Earth s atmosphere atmosphere , from about 60 km to 500 ... signals enter the ionosphere obliquely, they are Scattering back scattered from the ionized layer ... ground or water then Diffuse reflection diffusely reflects the incoming wave back towards the ionosphere ... the earth and ionosphere two or more times multihop propagation . Since at shallow incidence losses ... occurs in the waveguide formed by the ground and ionosphere, each serving as reflectors. With a single ... obtained with two or three hops. ref K.Rawer Wave Propagation in the Ionosphere . Kluwer Acad.Publ. ..., entering the ionosphere at a steep angle near vertical incidence may be back scattered down to Earth within a short range. Alternatively, signals beamed close to the horizon enter the ionosphere ... VHF signals with frequencies above about 30 MHz usually penetrate the ionosphere and are not returned ... than the distance between the Earth and the ionosphere. The maximum usable frequency for skywave propagation ... altitude layers the E layer in particular of the ionosphere largely disappear at night, the refractive layer of the ionosphere is much higher above the surface of the Earth at night. This leads ... pub releases 2006 02 su rgf021706.php Rare gamma ray flare disturbed ionosphere http www.df5ai.net ... more details
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- S4 Index
confusing date January 2007 Orphan date February 2009 expert subject Meteorology date February 2009 The math S 4 math Index is a standard scale social sciences index used to measure Ionosphere ionospheric disturbances. Real Time data This parameter is displayed in real time by many institutions http gps.ece.cornell.edu scintplot aopr.html at Arecibo Observatory http gps.ece.cornell.edu scintplot.html at Cornell University http 200.241.80.42 gps scintplot.html at INPE s Sao Luis Observatory in Brasil References reflist Category Atmosphere climate stub ... more details
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- Field aligned irregularities
Context date February 2009 Confusing date August 2007 Field Aligned Irregularities FAI are anisotropic perturbations of plasma density associated with magnetic field s. FAI are usually thought of in the context of the Earth s ionosphere , where several natural processes generate FAI in the E region and F region . References Reflist DEFAULTSORT Field Aligned Irregularities Category Atmosphere electromagnetism stub ... more details
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- Wall Peak
Orphan date December 2010 Wall Peak coor dm 71 3 S 65 23 E is the largest and northernmost of three sharply defined peaks about 5 nautical miles 9 km southeast of Husky Massif in the Prince Charles Mountains . Plotted from ANARE Australian National Antarctic Research Expeditions air photos taken in 1960. Named for B.H. Wall , ionosphere physicist at Wilkes Station in 1960. usgs gazetteer Category Mountains of Mac. Robertson Land MacRobertsonLand geo stub ... more details
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