|
Magnetic Declination
Magnetic declination (also called magnetic variation) is the angle between magnetic north and true north at a particular location on the Earth's surface. The angle can change over time due to polar wandering. Magnetic north is the direction that the north end of a magnetized compass needle points, which corresponds to the direction of the Earth's magnetic field lines. True north is the direction along a meridian towards the geographic North Pole. Somewhat more formally, Bowditch defines variation as "the angle between the magnetic and geographic meridians at any place, expressed in degrees and minutes east or west to indicate the direction of magnetic north from true north. The angle between magnetic and grid meridians is called grid magnetic angle, grid variation, or grivation." By convention, declination is positive when magnetic north is east of true north, and negative when it is to the west. '' Isogonic lines'' are lines on the Earth's surface along which the declination ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Magnetic Declination Chart For The International Geomagnetic Reference Field, 2005 (small)
Magnetism is the class of physical attributes that occur through a magnetic field, which allows objects to attract or repel each other. Because both electric currents and magnetic moments of elementary particles give rise to a magnetic field, magnetism is one of two aspects of electromagnetism. The most familiar effects occur in ferromagnetic materials, which are strongly attracted by magnetic fields and can be magnetized to become permanent magnets, producing magnetic fields themselves. Demagnetizing a magnet is also possible. Only a few substances are ferromagnetic; the most common ones are iron, cobalt, nickel, and their alloys. All substances exhibit some type of magnetism. Magnetic materials are classified according to their bulk susceptibility. Ferromagnetism is responsible for most of the effects of magnetism encountered in everyday life, but there are actually several types of magnetism. Paramagnetic substances, such as aluminium and oxygen, are weakly attracted to an a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Northern Hemisphere
The Northern Hemisphere is the half of Earth that is north of the equator. For other planets in the Solar System, north is defined by humans as being in the same celestial sphere, celestial hemisphere relative to the invariable plane of the Solar System as Earth's North Pole. Due to Earth's axial tilt of 23.439281°, there is a seasonal variation in the lengths of the day and night. There is also a seasonal variation in temperatures, which lags the variation in day and night. Conventionally, winter in the Northern Hemisphere is taken as the period from the December solstice (typically December 21 UTC) to the March equinox (typically March 20 UTC), while summer is taken as the period from the June solstice through to the September equinox (typically on 23 September UTC). The dates vary each year due to the difference between the calendar year and the Year#Astronomical years, astronomical year. Within the Northern Hemisphere, oceanic currents can change the weather patterns that aff ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Polaris
Polaris is a star in the northern circumpolar constellation of Ursa Minor. It is designated α Ursae Minoris (Latinisation of names, Latinized to ''Alpha Ursae Minoris'') and is commonly called the North Star or Pole Star. With an apparent magnitude that fluctuates around 1.98, it is the brightest star in the constellation and is readily visible to the naked eye at night. The position of the star lies less than angular distance, 1° away from the north celestial pole, making it the current northern pole star. The stable position of the star in the northern celestial hemisphere, Northern Sky makes it useful for celestial navigation, navigation. As the closest Cepheid variable its distance is used as part of the cosmic distance ladder. The revised ''Hipparcos'' stellar parallax gives a distance to Polaris of about , while the successor mission Gaia (spacecraft), ''Gaia'' gives a distance of about . Although appearing to the naked eye as a single point of light, Polar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Measuring Instrument
Instrumentation is a collective term for measuring instruments, used for indicating, measuring, and recording physical quantities. It is also a field of study about the art and science about making measurement instruments, involving the related areas of metrology, automation, and control theory. The term has its origins in the art and science of scientific instrument-making. Instrumentation can refer to devices as simple as direct-reading thermometers, or as complex as multi- sensor components of industrial control systems. Instruments can be found in laboratories, refineries, factories and vehicles, as well as in everyday household use (e.g., smoke detectors and thermostats). Measurement parameters Instrumentation is used to measure many parameters (physical values), including: *Pressure, either differential or static * Flow *Temperature * Levels of liquids, etc. *Moisture or humidity *Density *Viscosity * ionising radiation * Frequency * Current *Voltage * Induct ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Celestial Pole
The north and south celestial poles are the two points in the sky where Earth's axis of rotation, indefinitely extended, intersects the celestial sphere. The north and south celestial poles appear permanently directly overhead to observers at Earth's North Pole and South Pole, respectively. As Earth spins on its axis, the two celestial poles remain fixed in the sky, and all other celestial points appear to rotate around them, completing one circuit per day (strictly, per sidereal day). The celestial poles are also the poles of the celestial equatorial coordinate system, meaning they have declinations of +90 degrees and −90 degrees (for the north and south celestial poles, respectively). Despite their apparently fixed positions, the celestial poles in the long term do not actually remain permanently fixed against the background of the stars. Because of a phenomenon known as the precession of the equinoxes, the poles trace out circles on the celestial sphere, with a period ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Boussole De Déclinaison Lenoir
Boussole (French: "compass") may refer to: * French ship ''Boussole'', several ships *Boussole Rock, Jukdo (island) * Boussole Strait, in the Kuril Islands *''Boussole'', a novel by Mathias Énard Mathias Énard (born 1972) is a French novelist. He studied Persian and Arabic and spent long periods in the Middle East. He has lived in Barcelona for about fifteen years, interrupted in 2013 by a writing residency in Berlin. He won several aw ... *La Boussole, 1990s French hip hop group including Médine {{disambiguation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Earth Magnetic Field Declination From 1590 To 1990
Earth is the third planet from the Sun and the only astronomical object known to Planetary habitability, harbor life. This is enabled by Earth being an ocean world, the only one in the Solar System sustaining liquid surface water. Almost all of Earth's water is contained in its global ocean, covering Water distribution on Earth, 70.8% of Earth's crust. The remaining 29.2% of Earth's crust is land, most of which is located in the form of continental landmasses within Earth's land hemisphere. Most of Earth's land is at least somewhat humid and covered by vegetation, while large Ice sheet, sheets of ice at Polar regions of Earth, Earth's polar polar desert, deserts retain more water than Earth's groundwater, lakes, rivers, and Water vapor#In Earth's atmosphere, atmospheric water combined. Earth's crust consists of slowly moving tectonic plates, which interact to produce mountain ranges, volcanoes, and earthquakes. Earth's outer core, Earth has a liquid outer core that generates a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
NOAA Chart 12366 (2008)
The National Oceanic and Atmospheric Administration (NOAA ) is an American scientific and regulatory agency charged with forecasting weather, monitoring oceanic and atmospheric conditions, charting the seas, conducting deep-sea exploration, and managing fishing and protection of marine mammals and endangered species in the US exclusive economic zone. The agency is part of the United States Department of Commerce and is headquartered in Silver Spring, Maryland. History NOAA traces its history back to multiple agencies, some of which are among the earliest in the federal government: * United States Coast and Geodetic Survey, formed in 1807 * Weather Bureau of the United States, formed in 1870 * Bureau of Commercial Fisheries, formed in 1871 (research fleet only) * Coast and Geodetic Survey Corps, formed in 1917 The most direct predecessor of NOAA was the Environmental Science Services Administration (ESSA), into which several existing scientific agencies such as the Uni ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
USCGS Chart Number 361 (1884) , in the United States
{{dab ...
USCGS may refer to: * An abbreviation for the United States Coast and Geodetic Survey, a former scientific agency of the United States Government * US CGS, the United Nations Code for Trade and Transport Locations (UN/LOCODE) for College Park, Maryland College Park is a city in Prince George's County, Maryland, United States, located approximately from the northeast border of Washington, D.C. Its population was 34,740 at the 2020 United States census. It is the home of the University of Mary ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Long Island Sound
Long Island Sound is a sound (geography), marine sound and tidal estuary of the Atlantic Ocean. It lies predominantly between the U.S. state of Connecticut to the north and Long Island in New York (state), New York to the south. From west to east, the sound stretches from the East River and the Throgs Neck Bridge in New York City, along the North Shore of Long Island, to Block Island Sound. The sound forms part of the Intracoastal Waterway. A mix of freshwater from tributaries, and seawater, saltwater from the Atlantic Ocean, Long Island Sound is at its widest point and varies in depth from . Shoreline Major Connecticut cities on the Sound include Stamford, Connecticut, Stamford, Norwalk, Connecticut, Norwalk, Bridgeport, Connecticut, Bridgeport, New Haven, Connecticut, New Haven, and New London, Connecticut, New London. Cities on the New York side of the Sound include Rye (city), New York, Rye, Glen Cove, New York, Glen Cove, New Rochelle, New York, New Rochelle, North Hem ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
