An ocean is a body of saline water that composes much of a planets hydrosphere. On Earth, an ocean is one of the major divisions of the World Ocean. These are, in descending order by area, the Pacific, Indian, the word sea is often used interchangeably with ocean in American English but, strictly speaking, a sea is a body of saline water partly or fully enclosed by land. The ocean contains 97% of Earths water, and oceanographers have stated that less than 5% of the World Ocean has been explored, the total volume is approximately 1.35 billion cubic kilometers with an average depth of nearly 3,700 meters. As the world ocean is the component of Earths hydrosphere, it is integral to all known life, forms part of the carbon cycle. The world ocean is the habitat of 230,000 known species, but because much of it is unexplored, the origin of Earths oceans remains unknown, oceans are thought to have formed in the Hadean period and may have been the impetus for the emergence of life. Extraterrestrial oceans may be composed of water or other elements and compounds, the only confirmed large stable bodies of extraterrestrial surface liquids are the lakes of Titan, although there is evidence for the existence of oceans elsewhere in the Solar System.
Early in their histories and Venus are theorized to have had large water oceans. The Mars ocean hypothesis suggests that nearly a third of the surface of Mars was once covered by water, compounds such as salts and ammonia dissolved in water lower its freezing point so that water might exist in large quantities in extraterrestrial environments as brine or convecting ice. Unconfirmed oceans are speculated beneath the surface of many planets and natural satellites, notably. The Solar Systems giant planets are thought to have liquid atmospheric layers of yet to be confirmed compositions. Oceans may exist on exoplanets and exomoons, including surface oceans of water within a circumstellar habitable zone. Ocean planets are a type of planet with a surface completely covered with liquid. The concept of Ōkeanós has an Indo-European connection, Greek Ōkeanós has been compared to the Vedic epithet ā-śáyāna-, predicated of the dragon Vṛtra-, who captured the cows/rivers. Related to this notion, the Okeanos is represented with a dragon-tail on some early Greek vases, though generally described as several separate oceans, these waters comprise one global, interconnected body of salt water sometimes referred to as the World Ocean or global ocean.
This concept of a body of water with relatively free interchange among its parts is of fundamental importance to oceanography. The major oceanic divisions – listed below in descending order of area and volume – are defined in part by the continents, various archipelagos, Oceans are fringed by smaller, adjoining bodies of water such as seas, bays and straits. The Mid-Oceanic Ridge of the World are connected and form the Ocean Ridge, the continuous mountain range is 65,000 km long, and the total length of the oceanic ridge system is 80,000 km long
President Dwight D. Eisenhower established NASA in 1958 with a distinctly civilian orientation encouraging peaceful applications in space science. The National Aeronautics and Space Act was passed on July 29,1958, disestablishing NASAs predecessor, the new agency became operational on October 1,1958. Since that time, most US space exploration efforts have led by NASA, including the Apollo Moon landing missions, the Skylab space station. Currently, NASA is supporting the International Space Station and is overseeing the development of the Orion Multi-Purpose Crew Vehicle, the agency is responsible for the Launch Services Program which provides oversight of launch operations and countdown management for unmanned NASA launches. NASA shares data with various national and international such as from the Greenhouse Gases Observing Satellite. Since 2011, NASA has been criticized for low cost efficiency, from 1946, the National Advisory Committee for Aeronautics had been experimenting with rocket planes such as the supersonic Bell X-1.
In the early 1950s, there was challenge to launch a satellite for the International Geophysical Year. An effort for this was the American Project Vanguard, after the Soviet launch of the worlds first artificial satellite on October 4,1957, the attention of the United States turned toward its own fledgling space efforts. This led to an agreement that a new federal agency based on NACA was needed to conduct all non-military activity in space. The Advanced Research Projects Agency was created in February 1958 to develop technology for military application. On July 29,1958, Eisenhower signed the National Aeronautics and Space Act, a NASA seal was approved by President Eisenhower in 1959. Elements of the Army Ballistic Missile Agency and the United States Naval Research Laboratory were incorporated into NASA, earlier research efforts within the US Air Force and many of ARPAs early space programs were transferred to NASA. In December 1958, NASA gained control of the Jet Propulsion Laboratory, NASA has conducted many manned and unmanned spaceflight programs throughout its history.
Some missions include both manned and unmanned aspects, such as the Galileo probe, which was deployed by astronauts in Earth orbit before being sent unmanned to Jupiter, the experimental rocket-powered aircraft programs started by NACA were extended by NASA as support for manned spaceflight. This was followed by a space capsule program, and in turn by a two-man capsule program. This goal was met in 1969 by the Apollo program, reduction of the perceived threat and changing political priorities almost immediately caused the termination of most of these plans. NASA turned its attention to an Apollo-derived temporary space laboratory, to date, NASA has launched a total of 166 manned space missions on rockets, and thirteen X-15 rocket flights above the USAF definition of spaceflight altitude,260,000 feet. The X-15 was an NACA experimental rocket-powered hypersonic research aircraft, developed in conjunction with the US Air Force, the design featured a slender fuselage with fairings along the side containing fuel and early computerized control systems
It extends from the nominal red edge of the visible spectrum at 700 nanometers, to 1000000 nm. Most of the radiation emitted by objects near room temperature is infrared. Like all EMR, IR carries radiant energy, and behaves both like a wave and like its quantum particle, the photon, slightly more than half of the total energy from the Sun was eventually found to arrive on Earth in the form of infrared. The balance between absorbed and emitted infrared radiation has an effect on Earths climate. Infrared radiation is emitted or absorbed by molecules when they change their rotational-vibrational movements and it excites vibrational modes in a molecule through a change in the dipole moment, making it a useful frequency range for study of these energy states for molecules of the proper symmetry. Infrared spectroscopy examines absorption and transmission of photons in the infrared range, Infrared radiation is used in industrial and medical applications. Night-vision devices using active near-infrared illumination allow people or animals to be observed without the observer being detected, Infrared thermal-imaging cameras are used to detect heat loss in insulated systems, to observe changing blood flow in the skin, and to detect overheating of electrical apparatuses.
Thermal-infrared imaging is used extensively for military and civilian purposes, military applications include target acquisition, night vision and tracking. Humans at normal body temperature radiate chiefly at wavelengths around 10 μm, Infrared radiation extends from the nominal red edge of the visible spectrum at 700 nanometers to 1 mm. This range of wavelengths corresponds to a range of approximately 430 THz down to 300 GHz. Below infrared is the portion of the electromagnetic spectrum. Sunlight, at a temperature of 5,780 kelvins, is composed of near thermal-spectrum radiation that is slightly more than half infrared. At zenith, sunlight provides an irradiance of just over 1 kilowatt per square meter at sea level, of this energy,527 watts is infrared radiation,445 watts is visible light, and 32 watts is ultraviolet radiation. Nearly all the radiation in sunlight is near infrared, shorter than 4 micrometers. On the surface of Earth, at far lower temperatures than the surface of the Sun, almost all thermal radiation consists of infrared in mid-infrared region, much longer than in sunlight.
Of these natural thermal radiation processes only lightning and natural fires are hot enough to produce much visible energy, thermal infrared radiation has a maximum emission wavelength, which is inversely proportional to the absolute temperature of object, in accordance with Wiens displacement law. Therefore, the band is often subdivided into smaller sections. Due to the nature of the blackbody radiation curves, typical hot objects, such as exhaust pipes, the three regions are used for observation of different temperature ranges, and hence different environments in space
California Institute of Technology
The California Institute of Technology is a private doctorate-granting university located in Pasadena, United States. The vocational and preparatory schools were disbanded and spun off in 1910, the university is one among a small group of Institutes of Technology in the United States which is primarily devoted to the instruction of technical arts and applied sciences. Caltech has six divisions with strong emphasis on science and engineering, managing $332 million in 2011 in sponsored research. Its 124-acre primary campus is located approximately 11 mi northeast of downtown Los Angeles, first-year students are required to live on campus, and 95% of undergraduates remain in the on-campus House System at Caltech. Although Caltech has a tradition of practical jokes and pranks. The Caltech Beavers compete in 13 intercollegiate sports in the NCAA Division IIIs Southern California Intercollegiate Athletic Conference, Caltech is frequently cited as one of the worlds best universities. There are 112 faculty members who have elected to the United States National Academies.
In addition, numerous faculty members are associated with the Howard Hughes Medical Institute as well as NASA, according to a 2015 Pomona College study, Caltech ranked number one in the U. S. for the percentage of its graduates who go on to earn a PhD. Caltech started as a school founded in Pasadena in 1891 by local businessman and politician Amos G. Throop. The school was known successively as Throop University, Throop Polytechnic Institute, the vocational school was disbanded and the preparatory program was split off to form an independent Polytechnic School in 1907. At a time when research in the United States was still in its infancy, George Ellery Hale. He joined Throops board of trustees in 1907, and soon began developing it and he engineered the appointment of James A. B. Scherer, a literary scholar untutored in science but a capable administrator and fund raiser, scherer persuaded retired businessman and trustee Charles W. Gates to donate $25,000 in seed money to build Gates Laboratory, the first science building on campus.
In 1910, Throop moved to its current site, arther Fleming donated the land for the permanent campus site. The promise of Throop attracted physical chemist Arthur Amos Noyes from MIT to develop the institution and assist in establishing it as a center for science, with the onset of World War I, Hale organized the National Research Council to coordinate and support scientific work on military problems. This institution, with its able investigators and excellent research laboratories, through the National Research Council, Hale simultaneously lobbied for science to play a larger role in national affairs, and for Throop to play a national role in science. During the course of the war, Hale and Millikan worked together in Washington on the NRC, they continued their partnership in developing Caltech. Under the leadership of Hale and Millikan, Caltech grew to prominence in the 1920s
In radio and electronics, an antenna, or aerial, is an electrical device which converts electric power into radio waves, and vice versa. It is usually used with a transmitter or radio receiver. In reception, an antenna intercepts some of the power of a wave in order to produce a tiny voltage at its terminals. Antennas are essential components of all equipment that uses radio, typically an antenna consists of an arrangement of metallic conductors, electrically connected to the receiver or transmitter. These time-varying fields radiate away from the antenna into space as a transverse electromagnetic field wave. Antennas can be designed to transmit and receive radio waves in all directions equally. The first antennas were built in 1888 by German physicist Heinrich Hertz in his experiments to prove the existence of electromagnetic waves predicted by the theory of James Clerk Maxwell. Hertz placed dipole antennas at the point of parabolic reflectors for both transmitting and receiving. He published his work in Annalen der Physik und Chemie, the words antenna and aerial are used interchangeably.
Occasionally the term aerial is used to mean a wire antenna, note the important international technical journal, the IEEE Transactions on Antennas and Propagation. In the United Kingdom and other areas where British English is used, the origin of the word antenna relative to wireless apparatus is attributed to Italian radio pioneer Guglielmo Marconi. In the summer of 1895, Marconi began testing his wireless system outdoors on his fathers estate near Bologna, Marconi discovered that by raising the aerial wire above the ground and connecting the other side of his transmitter to ground, the transmission range was increased. Soon he was able to transmit signals over a hill, a distance of approximately 2.4 kilometres, in Italian a tent pole is known as lantenna centrale, and the pole with the wire was simply called lantenna. Until wireless radiating transmitting and receiving elements were simply as aerials or terminals. Because of his prominence, Marconis use of the word spread among wireless researchers.
In common usage, the antenna may refer broadly to an entire assembly including support structure, enclosure. Especially at microwave frequencies, an antenna may include not only the actual electrical antenna. An antenna, in converting radio waves to electrical signals or vice versa, is a form of transducer, Antennas are required by any radio receiver or transmitter to couple its electrical connection to the electromagnetic field
Geographic information system
A geographic information system is a system designed to capture, manipulate, analyze and present spatial or geographic data. What goes beyond a GIS is a spatial data infrastructure, a concept that has no such restrictive boundaries, in general, the term describes any information system that integrates, edits, analyzes and displays geographic information. GIS applications are tools that allow users to create interactive queries, analyze spatial information, edit data in maps, Geographic information science is the science underlying geographic concepts and systems. GIS is a term that can refer to a number of different technologies, processes. It is attached to operations and has many applications related to engineering, management, transport/logistics, telecommunications. For that reason, GIS and location intelligence applications can be the foundation for many location-enabled services that rely on analysis, GIS can relate unrelated information by using location as the key index variable. Locations or extents in the Earth space–time may be recorded as dates/times of occurrence, and x, y, and z coordinates representing, latitude, all Earth-based spatial–temporal location and extent references should be relatable to one another and ultimately to a real physical location or extent.
This key characteristic of GIS has begun to open new avenues of scientific inquiry, the first known use of the term geographic information system was by Roger Tomlinson in the year 1968 in his paper A Geographic Information System for Regional Planning. Tomlinson is acknowledged as the father of GIS, one of the first applications of spatial analysis in epidemiology is the 1832 Rapport sur la marche et les effets du choléra dans Paris et le département de la Seine. The French geographer Charles Picquet represented the 48 districts of the city of Paris by halftone color gradient according to the number of deaths by cholera per 1,000 inhabitants and this was one of the earliest successful uses of a geographic methodology in epidemiology. The early 20th century saw the development of photozincography, which allowed maps to be split into layers, for one layer for vegetation. This work was drawn on glass plates but plastic film was introduced, with the advantages of being lighter, using less storage space and being less brittle.
When all the layers were finished, they were combined into one using a large process camera. Once color printing came in, the idea was used for creating separate printing plates for each color. Computer hardware development spurred by nuclear weapon research led to general-purpose computer mapping applications by the early 1960s, the year 1960 saw the development of the worlds first true operational GIS in Ottawa, Canada by the federal Department of Forestry and Rural Development. A rating classification factor was added to permit analysis. CGIS was an improvement over computer mapping applications as it provided capabilities for overlay, measurement and it supported a national coordinate system that spanned the continent, coded lines as arcs having a true embedded topology and it stored the attribute and locational information in separate files. As a result of this, Tomlinson has become known as the father of GIS, CGIS lasted into the 1990s and built a large digital land resource database in Canada
Earth, otherwise known as the World, or the Globe, is the third planet from the Sun and the only object in the Universe known to harbor life. It is the densest planet in the Solar System and the largest of the four terrestrial planets, according to radiometric dating and other sources of evidence, Earth formed about 4.54 billion years ago. Earths gravity interacts with objects in space, especially the Sun. During one orbit around the Sun, Earth rotates about its axis over 365 times, Earths axis of rotation is tilted, producing seasonal variations on the planets surface. The gravitational interaction between the Earth and Moon causes ocean tides, stabilizes the Earths orientation on its axis, Earths lithosphere is divided into several rigid tectonic plates that migrate across the surface over periods of many millions of years. About 71% of Earths surface is covered with water, mostly by its oceans, the remaining 29% is land consisting of continents and islands that together have many lakes and other sources of water that contribute to the hydrosphere.
The majority of Earths polar regions are covered in ice, including the Antarctic ice sheet, Earths interior remains active with a solid iron inner core, a liquid outer core that generates the Earths magnetic field, and a convecting mantle that drives plate tectonics. Within the first billion years of Earths history, life appeared in the oceans and began to affect the Earths atmosphere and surface, some geological evidence indicates that life may have arisen as much as 4.1 billion years ago. Since then, the combination of Earths distance from the Sun, physical properties, in the history of the Earth, biodiversity has gone through long periods of expansion, occasionally punctuated by mass extinction events. Over 99% of all species that lived on Earth are extinct. Estimates of the number of species on Earth today vary widely, over 7.4 billion humans live on Earth and depend on its biosphere and minerals for their survival. Humans have developed diverse societies and cultures, the world has about 200 sovereign states, the modern English word Earth developed from a wide variety of Middle English forms, which derived from an Old English noun most often spelled eorðe.
It has cognates in every Germanic language, and their proto-Germanic root has been reconstructed as *erþō, earth was written in lowercase, and from early Middle English, its definite sense as the globe was expressed as the earth. By early Modern English, many nouns were capitalized, and the became the Earth. More recently, the name is simply given as Earth. House styles now vary, Oxford spelling recognizes the lowercase form as the most common, another convention capitalizes Earth when appearing as a name but writes it in lowercase when preceded by the. It almost always appears in lowercase in colloquial expressions such as what on earth are you doing, the oldest material found in the Solar System is dated to 4. 5672±0.0006 billion years ago. By 4. 54±0.04 Gya the primordial Earth had formed, the formation and evolution of Solar System bodies occurred along with the Sun
The Space Shuttle was a partially reusable low Earth orbital spacecraft system operated by the U. S. National Aeronautics and Space Administration, as part of the Space Shuttle program. Its official program name was Space Transportation System, taken from a 1969 plan for a system of reusable spacecraft of which it was the only item funded for development, the first of four orbital test flights occurred in 1981, leading to operational flights beginning in 1982. Five complete Shuttle systems were built and used on a total of 135 missions from 1981 to 2011, the Shuttle fleets total mission time was 1322 days,19 hours,21 minutes and 23 seconds. Shuttle components included the Orbiter Vehicle, a pair of solid rocket boosters. The Shuttle was launched vertically, like a rocket, with the two SRBs operating in parallel with the OVs three main engines, which were fueled from the ET. The SRBs were jettisoned before the vehicle reached orbit, and the ET was jettisoned just before orbit insertion, at the conclusion of the mission, the orbiter fired its OMS to de-orbit and re-enter the atmosphere.
The orbiter glided as a spaceplane to a landing, usually at the Shuttle Landing Facility of KSC or Rogers Dry Lake in Edwards Air Force Base. After landing at Edwards, the orbiter was back to the KSC on the Shuttle Carrier Aircraft. The first orbiter, was built in 1976 for use in Approach, four fully operational orbiters were initially built, Challenger and Atlantis. Of these, two were lost in accidents, Challenger in 1986 and Columbia in 2003, with a total of fourteen astronauts killed. A fifth operational orbiter, was built in 1991 to replace Challenger, the Space Shuttle was retired from service upon the conclusion of Atlantiss final flight on July 21,2011. Nixons post-Apollo NASA budgeting withdrew support of all components except the Shuttle. The vehicle consisted of a spaceplane for orbit and re-entry, fueled by liquid hydrogen and liquid oxygen tanks. The first of four orbital test flights occurred in 1981, leading to operational flights beginning in 1982, all launched from the Kennedy Space Center, Florida.
The system was retired from service in 2011 after 135 missions, the program ended after Atlantis landed at the Kennedy Space Center on July 21,2011. Major missions included launching numerous satellites and interplanetary probes, conducting space science experiments, the first orbiter vehicle, named Enterprise, was built for the initial Approach and Landing Tests phase and lacked engines, heat shielding, and other equipment necessary for orbital flight. A total of five operational orbiters were built, and of these and it was used for orbital space missions by NASA, the US Department of Defense, the European Space Agency and Germany. The United States funded Shuttle development and operations except for the Spacelab modules used on D1, sL-J was partially funded by Japan
An altimeter or an altitude meter is an instrument used to measure the altitude of an object above a fixed level. The measurement of altitude is called altimetry, which is related to the term bathymetry, altitude can be determined based on the measurement of atmospheric pressure. The greater the altitude, the lower the pressure, when a barometer is supplied with a nonlinear calibration so as to indicate altitude, the instrument is called a pressure altimeter or barometric altimeter. A pressure altimeter is the altimeter found in most aircraft and mountain climbers use wrist-mounted or hand-held altimeters, in addition to other navigational tools such as a map, magnetic compass, or GPS receiver. The calibration of an altimeter follows the equation z = c T log , where c is a constant, T is the temperature, P is the pressure at altitude z. The constant c depends on the acceleration of gravity and the mass of the air. A barometric altimeter, used along with a map, can help to verify ones location.
An altimeter is the most important piece of skydiving equipment, after the parachute itself, altitude awareness is crucial at all times during the jump, and determines the appropriate response to maintain safety. This is the most basic and common type, and is used by all student skydivers. The common design has a face marked from 0 to 4000m, the face plate sports sections prominently marked with yellow and red respectively, signifying the recommended deployment altitude, as well as emergency procedure decision altitude. Some advanced electronic altimeters are available which use of the familiar analogue display. Digital visual altimeters, mounted on the wrist or hand and this type always operates electronically, and conveys the altitude as a number, rather than a pointer on a dial. An electronic altimeter is turned on on the ground before jump, if the intended landing zone is at a different elevation than the takeoff point, the user needs to input the appropriate offset by using a designated function.
These are inserted into ones helmet, and emit a warning tone at a predefined altitude, audibles are strictly auxiliary devices, and do not replace, but complement a visual altimeter which remains the primary tool for maintaining altitude awareness. Audibles are not recommended and often banned from use by student skydivers and these do not show the precise altitude, but rather help maintain a general indicator in ones peripheral vision. The exact choice of altimeters depends heavily on the individual preferences, experience level, primary disciplines. On one end of the spectrum, a demonstration jump with water landing and no free fall might waive the mandated use of altimeters. Another skydiver doing similar types of jumps might wear a digital altimeter for their primary visual one, in aircraft, an aneroid barometer measures the atmospheric pressure from a static port outside the aircraft
The lineage of the name begins with the JASO1 meeting in Toulouse, France to study the problems of assimilating altimeter data in models. Jason as an acronym stands for Joint Altimetry Satellite Oceanography Network, additionally it is used to reference the mythical quest for knowledge of Jason and the Argonauts. It is the successor to the TOPEX/Poseidon mission, which measured ocean surface topography from 1992 through 2005, like its predecessor, Jason-1 is a joint project between the NASA and CNES space agencies. Jason-1s successor, the Ocean Surface Topography Mission on the Jason-2 satellite, was launched in June 2008 and these satellites provide a unique global view of the oceans that is impossible to acquire using traditional ship-based sampling. As did TOPEX/Poseidon, Jason-1 uses an altimeter to measure the hills and these measurements of sea surface topography allow scientists to calculate the speed and direction of ocean currents and monitor global ocean circulation. The global ocean is Earths primary storehouse of solar energy, Jason-1s measurements of sea surface height reveal where this heat is stored, how it moves around Earth by ocean currents, and how these processes affect weather and climate.
Jason-1 was launched on December 7,2001 from Californias Vandenberg Air Force Base aboard a Delta II rocket, during the first months Jason-1 shared an almost identical orbit to TOPEX/Poseidon, which allowed for cross calibration. At the end of period, the older satellite was moved to a new orbit midway between each Jason ground track. Jason has a cycle of 10 days. On 16 March 2002, Jason-1 experienced a sudden attitude upset, soon after this incident, two new small pieces of space debris were observed in orbits slightly lower than Jason-1s, and spectroscopic analysis eventually proved them to have originated from Jason-1. In 2011, it was determined that the pieces of debris had most likely been ejected from Jason-1 by an unidentified, small high-speed particle hitting one of the spacecrafts solar panels. Orbit maneuvers in 2009 put the Jason-1 satellite on the side of Earth from the Jason-2 satellite. Jason-1 now flies over the region of the ocean that Jason-2 flew over five days earlier. Its ground tracks fall midway between those of Jason-2, which are about 315 kilometers apart at the equator and this interleaved tandem mission provides twice the number of measurements of the oceans surface, bringing smaller features such as ocean eddies into view.
The tandem mission helps pave the way for a future ocean altimeter mission that would much more detailed data with its single instrument than the two Jason satellites now do together. The program is named after the Greek mythological hero Jason, Jason-1 has five 5 instruments, Poseidon 2 - Nadir pointing Radar Altimeter using C band and Ku band for measuring height above sea surface. Jason Microwave Radiometer - measures water vapor along altimeter path to correct for pulse delay DORIS for orbit determination to within 10 cm or less, the Jason-1 satellite, its altimeter instrument and a position-tracking antenna were built in France. The radiometer, Global Positioning System receiver and laser retroreflector array were built in the United States, TOPEX/Poseidon and Jason-1 have led to major advances in the science of physical oceanography and in climate studies
The Lockheed Corporation was an American aerospace company. Lockheed was founded in 1912 and merged with Martin Marietta to form Lockheed Martin in 1995, the Alco Hydro-Aeroplane Company was established in San Francisco in 1912 by the brothers Allan and Malcolm Loughead. Following the Model F-1, the company invested heavily in the design, the asking price of $2500 could not compete in a market that was saturated with post World War 1 $350 Curtiss JN-4s and De Haviland trainers. The Loughead Aircraft Manufacturing Company closed its doors in 1921, in 1926, Allan Loughead, Jack Northrop, and Kenneth Jay secured funding to form the Lockheed Aircraft Company in Hollywood. This new company utilized some of the technology originally developed for the Model S-1 to design the Vega Model. In March 1928, the relocated to Burbank, California. From 1926-28 the company produced over 80 aircraft and employed more than 300 workers who by April 1929 were building five aircraft per week, in July 1929, majority shareholder Fred Keeler sold 87% of the Lockheed Aircraft Company to Detroit Aircraft Corporation.
In August 1929, Allan Lockheed resigned, the Great Depression ruined the aircraft market, and Detroit Aircraft went bankrupt. A group of headed by brothers Robert and Courtland Gross. The syndicate bought the company for a mere $40,000, Allan Lockheed himself had planned to bid for his own company, but had raised only $50,000, which he felt was too small a sum for a serious bid. In 1934, Robert E. Gross was named chairman of the new company, the Lockheed Aircraft Corporation and his brother Courtlandt S. Gross was a co-founder and executive, succeeding Robert as Chairman following his death in 1961. The company was named the Lockheed Corporation in 1977, in the 1930s, Lockheed spent $139,400 to develop the Model 10 Electra, a small twin-engined transport. The company sold 40 in the first year of production, amelia Earhart and her navigator, Fred Noonan, flew it in their failed attempt to circumnavigate the world in 1937. Subsequent designs, the Lockheed Model 12 Electra Junior and the Lockheed Model 14 Super Electra expanded their market.
The Lockheed Model 14 formed the basis for the Hudson bomber and its primary role was submarine hunting. The Model 14 Super Electra were sold abroad, and more than 100 were license-built in Japan for use by the Imperial Japanese Army, the P-38 was the only American fighter aircraft in production throughout American involvement in the war, from Pearl Harbor to Victory over Japan Day. It filled ground-attack, air-to-air, and even strategic bombing roles in all theaters of the war in which the United States operated, the Lockheed Vega factory was located next to Burbanks Union Airport which it had purchased in 1940. During the war, the area was camouflaged to fool enemy aerial reconnaissance
Microwaves are a form of electromagnetic radiation with wavelengths ranging from one meter to one millimeter, with frequencies between 300 MHz and 300 GHz. Different sources define different frequency ranges as microwaves, the broad definition includes both UHF and EHF bands. A more common definition in radio engineering is the range between 1 and 100 GHz, in all cases, microwaves include the entire SHF band at minimum. Frequencies in the range are often referred to by their IEEE radar band designations, S, C, X, Ku, K, or Ka band. The prefix micro- in microwave is not meant to suggest a wavelength in the micrometer range and it indicates that microwaves are small, compared to waves used in typical radio broadcasting, in that they have shorter wavelengths. The boundaries between far infrared, terahertz radiation and ultra-high-frequency radio waves are fairly arbitrary and are used variously between different fields of study. At the high end of the band they are absorbed by gases in the atmosphere, microwaves are extremely widely used in modern technology.
Although at the low end of the band they can pass through building walls enough for useful reception, therefore on the surface of the Earth microwave communication links are limited by the visual horizon to about 30 -40 miles. Microwaves are absorbed by moisture in the atmosphere, and the attenuation increases with frequency, beginning at about 40 GHz, atmospheric gases begin to absorb microwaves, so above this frequency microwave transmission is limited to a few kilometers. A spectral band structure causes absorption peaks at specific frequencies, in a microwave beam directed at an angle into the sky, a small amount of the power will be randomly scattered as the beam passes through the troposphere. A sensitive receiver beyond the horizon with a high gain antenna focused on that area of the troposphere can pick up the signal. This technique has been used at frequencies between 0.45 and 5 GHz in tropospheric scatter communication systems to communicate beyond the horizon and their short wavelength allows narrow beams of microwaves to be produced by conveniently small high gain antennas from a half meter to 5 meters in diameter.
Therefore beams of microwaves are used for point-to-point communication links, an advantage of narrow beams is that they allow frequency reuse by nearby transmitters. Parabolic antennas are the most widely used directive antennas at microwave frequencies, flat microstrip antennas are being increasingly used in consumer devices. Where omnidirectional antennas are required, for example in wireless devices and Wifi routers for wireless LANs, small monopoles, dipole, or patch antennas are used. Due to the high cost and maintenance requirements of waveguide runs, the term microwave has a more technical meaning in electromagnetics and circuit theory. As a consequence, practical microwave circuits tend to away from the discrete resistors, capacitors. Open-wire and coaxial transmission lines used at lower frequencies are replaced by waveguides and stripline, high-power microwave sources use specialized vacuum tubes to generate microwaves