- solar flare
flare (def. 22).[1935-40]
* * *Flares develop in a few minutes and may last several hours, releasing intense X rays and streams of energetic particles. They appear to be connected with changes in the Sun's magnetic fields during the solar cycle. The ejected particles take a day or two to reach the vicinity of Earth, where they can disrupt radio communications and cause auroras, and may pose a radiation hazard to astronauts.
* * *sudden intense brightening of a small part of the Sun's (Sun) chromosphere, usually in the vicinity of a magnetic inversion near a sunspot group. The flare develops in a few minutes, or even seconds, and may last several hours. High-energy particles, electron streams, hard X-rays (X-ray), and radio bursts are often emitted, and a shock wave occurs when the flare interacts with the interplanetary medium. The flare occurs above the surface in the chromosphere, and energy deposited in the surface brings up a superhot cloud at about 100 million K (100 million °C, or 180 million °F), which is a strong, long-lasting source of X-rays. Smaller flares do not show all these attributes, and flares rarely occur in the three or four years of sunspot minimum. The biggest flares occur in association with large sunspots that have sharp magnetic gradients and large currents, which are the source of the flare energy. There is a class of spotless flares associated with filament eruptions; they are large and sometimes produce coronal mass ejections but produce few high-energy particles.Flares are mainly observed from the surface of Earth in the Hα spectral line, but they are prominent in other lines and are brighter than the whole Sun in X-rays and in ultraviolet (ultraviolet radiation) light. Flares are the main source of important solar-terrestrial effects, such as disruption of radio communications and the induction of strong currents in power lines, and a few flares each year are a potential radiation hazard to human beings in space. X-ray photons (photon) and high-energy particles arrive immediately, but the main particle flux arrives a few days later.
* * *
Look at other dictionaries:
solar flare — n. a sudden, short lived increase of intensity in the light of the sun, usually near sunspots, often accompanied by a large increase in cosmic rays, X rays, etc. and by resultant magnetic storms … English World dictionary
Solar flare — A solar flare is a violent explosion in a star s (like the Sun s) atmosphere releasing as much energy as 6 times; 1025 Joules.cite journal last=Kopp first=G. coauthors=Lawrence, G and Rottman, G. year=2005… … Wikipedia
solar flare — noun a sudden eruption of intense high energy radiation from the sun s surface; associated with sunspots and radio interference • Syn: ↑flare • Hypernyms: ↑solar radiation * * * ˌsolar ˈflare 7 [solar flare] … Useful english dictionary
solar flare — noun Date: 1938 a sudden temporary outburst of energy from a small area of the sun s surface called also flare … New Collegiate Dictionary
solar flare — so′lar flare′ n. astron. a brief, sudden brightening of the sun s atmosphere that accompanies a burst of radiation from a sunspot • Etymology: 1935–40 … From formal English to slang
Solar Flare — A huge eruption of the Sun s matter from its surface. These columns and loops of matter may be hundreds of kilometers high and affect radio signals on Earth. See Solar Cycle … The writer's dictionary of science fiction, fantasy, horror and mythology
solar flare — noun A violent explosion in the Suns atmosphere … Wiktionary
solar flare — volcanic eruption of the surface of the sun … English contemporary dictionary
solar flare — noun Astronomy a brief eruption of intense high energy radiation from the sun s surface … English new terms dictionary
solar flare — /soʊlə ˈflɛə/ (say sohluh flair) noun a short lived, high temperature outburst, seen as a bright area in the sun s atmosphere … Australian English dictionary