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A constant number. 1, -16, .3534, 7346 are all scalars.
- Browse Related Terms: Cosmological Constant, Λ, Critical Density, Dark Energy, Deceleration, Energy Density, inflation, Lambda, Λ, Matter-Dominated Universe, model, Quantum Fluctuations, Radiation-Dominated Universe, scalar, Steady State Theory
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When refering to photons and light, scattering describes the phenomenon of a source absorbing, and then emanating light in all directions. For example, when light from our sun comes into contact with the clouds in our atmosphere, it scatters, meaning it is absorbed by the clouds and the re-emitted in all directions. On a clear day the light seems to come from a small point, but on cloudy days it seems to come from all directions.
- Browse Related Terms: Absorption Spectra, Black Body Spectrum, Electromagnetic Radiation, Energy Spectrum, Light, period, Scatter, Spectra, spectral line, Wavelength
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The level of random noise in the temperature measurement.
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Occurring at the same time.
- Browse Related Terms: Angular resolution, Equilibrium, Feed, Fusion, hypothesis, initial, Kelvin, Mid-Class Explorer (MIDEX), Nucleosynthesis, Quantum Mechanics, Simultaneous
An approximately 11-year pattern in the number of sunspots, coronal mass ejections (CMEs), solar flares, and other solar activity. About every 11 years the Sun’s magnetic field changes from north to south, and then back again in another 11 years.
The approximately 11-year period during which the frequency and number of Sunspots, coronal mass ejections, solar flares, and other solar activity rises and falls. Also called the Sunspot cycle.
- Browse Related Terms: Magnetic Loops, Magnetogram, Maunder Minimum, Solar Cycle, Solar Maximum, Solar Minimum, sunspot, Sunspot Group, Zeeman effect
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The passing of the Moon between the Sun and Earth. In a total solar eclipse, the Moon blocks all light from the solar disk, allowing us to see the solar corona more clearly.
- Browse Related Terms: Chromosphere, Corona, Coronagraph, Coronal Hole, Filament, Photosphere, Prominence, Prominences, Solar Eclipse, Transition Region
An explosive release of electromagnetic radiation and huge quantities of charged particles from a small area of the solar surface. Solar flares are marked by a sudden brightening near a Sunspot or prominence. The radiation released includes X-rays and radio waves. Solar flares and CMEs often occur together, but what connections may exist between them is a matter of debate.
- Browse Related Terms: 171, Electromagnetic Spectrum, Faculae, Gamma Rays, Infrared, Infrared (IR) Radiation, Ionization, radiation, Radio Waves, Solar Flare, Solar Ultraviolet Irradiance, Spectrograph, spectrum, Ultraviolet, Visible Light, Wavelength, X-Rays
The month(s) during the 11-year solar cycle when the number of Sunspots reaches a maximum.
- Browse Related Terms: Magnetic Loops, Magnetogram, Maunder Minimum, Solar Cycle, Solar Maximum, Solar Minimum, sunspot, Sunspot Group, Zeeman effect
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The month(s) during the 11-year solar cycle when the number of Sunspots is lowest.
- Browse Related Terms: Magnetic Loops, Magnetogram, Maunder Minimum, Solar Cycle, Solar Maximum, Solar Minimum, sunspot, Sunspot Group, Zeeman effect
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The amount of radiant energy of a particular wavelength that falls on a surface in a given amount of time.
- Browse Related Terms: Convective Zone, Granules, Irradiation, Solar Spectral Irradiance (SSI), Sunspot Cycle, Total Solar Irradiance
The Sun and the family of objects that orbit it. The Solar System includes things like planets, moons, comets and asteroids, and a mysterious form of matter called a plasma.
- Browse Related Terms: AURORA, Auroral Oval, Coronal Mass Ejection (CME), Geosynchronous, Heliosphere, Magnetic Field, Magnetic Field Lines, Magnetic Storms and Substorms, Magnetosphere, Magnetotail, Radiation Belt, Solar System, Solar Wind, Space Weather
The amount of energy released from the Sun in the ultraviolet portion of the spectrum at wavelengths shorter than 400 nm.
- Browse Related Terms: 171, Electromagnetic Spectrum, Faculae, Gamma Rays, Infrared, Infrared (IR) Radiation, Ionization, radiation, Radio Waves, Solar Flare, Solar Ultraviolet Irradiance, Spectrograph, spectrum, Ultraviolet, Visible Light, Wavelength, X-Rays
A continuous stream of tiny charged particles coming from the Sun. The solar wind interacts with the magnetic field and atmosphere of Earth causing auroras. The solar wind pours out of the Sun at 200 tons per second and a million miles per hour.
A stream of plasma coming out of the Sun in all directions at very high speeds—an average of about 400 km/sec, or a million mph. Solar wind is responsible for the tails of comets pointing away from the Sun and for the shape of the magnetosphere around the planets. Solar wind can also have a measurable effect on the flight paths of spacecraft.
- Browse Related Terms: AURORA, Auroral Oval, Coronal Mass Ejection (CME), Geosynchronous, Heliosphere, Magnetic Field, Magnetic Field Lines, Magnetic Storms and Substorms, Magnetosphere, Magnetotail, Radiation Belt, Solar System, Solar Wind, Space Weather
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The conditions and processes occurring in space which have the potential to affect the near Earth environment. Space Weather processes can include changes in the interplanetary magnetic field, coronal mass ejections from the Sun, and disturbances in Earth's magnetic field. The effects of space weather can range from damage to satellites to disruption of power grids on Earth.
Refers to conditions on the Sun, in the solar wind, and in Earth’s space (magnetic field, ionosphere, and thermosphere) that can influence space- and ground-based technological systems and endanger humans working in space. Adverse conditions in the space environment can disrupt satellite operations, communications, navigation, and electric power distribution grids.
- Browse Related Terms: AURORA, Auroral Oval, Coronal Mass Ejection (CME), Geosynchronous, Heliosphere, Magnetic Field, Magnetic Field Lines, Magnetic Storms and Substorms, Magnetosphere, Magnetotail, Radiation Belt, Solar System, Solar Wind, Space Weather
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The theory of relativity says that time cannot be treated absolutely separately from space, only in one observer's relative view. So space and time together describe a four dimensional universe.
- Browse Related Terms: Aberration, Big Bang, Cosmological Principle, Curvature of Spacetime, General Relativity, Hubble's Law, Milky Way, Quasar, Recede, Relativity, Spacetime, Supernova
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A range of different measurements. In terms of physics, spectra usually refers to the different wavelengths, or colors (if in the visible range) of light that can be emitted from a certain element, when excited. For example, sodium emits several shades of yellow and orange when its electrons are excited. This is the same phenomenon that takes place in neon and flourescent lights. These elements are made to emit light by running an electric current through a chamber of their gas form.
- Browse Related Terms: Absorption Spectra, Black Body Spectrum, Electromagnetic Radiation, Energy Spectrum, Light, period, Scatter, Spectra, spectral line, Wavelength
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An emission (bright) or absorption (dark) of light at a specific frequency or wavelength.
- Browse Related Terms: Absorption Spectra, Black Body Spectrum, Electromagnetic Radiation, Energy Spectrum, Light, period, Scatter, Spectra, spectral line, Wavelength
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A device that separates light by wavelength (color) in order to produce a spectrum that allows for the identification of elements within the light source.
- Browse Related Terms: 171, Electromagnetic Spectrum, Faculae, Gamma Rays, Infrared, Infrared (IR) Radiation, Ionization, radiation, Radio Waves, Solar Flare, Solar Ultraviolet Irradiance, Spectrograph, spectrum, Ultraviolet, Visible Light, Wavelength, X-Rays
Electromagnetic radiation arranged in order of wavelength from Ion wavelength radio waves to short wavelength gamma rays. A rainbow is a natural spectrum of visible light from the Sun. Spectra are often punctuated by emission or absorption lines, which can be examined to reveal the composition and motion of the radiating source.
- Browse Related Terms: 171, Electromagnetic Spectrum, Faculae, Gamma Rays, Infrared, Infrared (IR) Radiation, Ionization, radiation, Radio Waves, Solar Flare, Solar Ultraviolet Irradiance, Spectrograph, spectrum, Ultraviolet, Visible Light, Wavelength, X-Rays
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A celestial object whose intrinsic brightness is known or can be estimated by some physical principle. Therefore its observed brightness tells us its distance.
- Browse Related Terms: Angular Size, Apparent luminosities, Constant of Proportionality, Dark Matter, Flux, Heavenly Bodies, Intrinsic Luminosity, Inverse Square, Luminosity, Main Sequence Star, Observed Brightness, Parallax, Parsec, Relative Brightness, Standard Candle, Type Ia Supernova, Variable Stars