auroral activity

См. также в других словарях:

• aurora/auroral propagation — The phenomenon of the electromagnetic energy being returned to the earth as a result of unusual solar activity causing aurora. The aurora occur in the ionosphere. Theoretically, auroral propagation is possible, when the aurora are active, between …   Aviation dictionary

• Aurora (astronomy) — Aurora Borealis redirects here. For other uses, see Aurora Borealis (disambiguation). Aurora Australis redirects here. For the ship, see Aurora Australis (icebreaker). For the book, see Aurora Australis (book). Northern lights redirects here. For …   Wikipedia

• ionosphere and magnetosphere — ▪ atmospheric science Introduction       regions of Earth s (Earth) atmosphere in which the number of electrically charged particles ions (ion) and electrons (electron) are large enough to affect the propagation of radio waves (electromagnetic… …   Universalium

• geomagnetic field — Magnetic field associated with the Earth. It is essentially dipolar (i.e., it has two poles, the northern and southern magnetic poles) on the Earth s surface. Away from the surface, the field becomes distorted. Most geomagnetists explain the… …   Universalium

• Solar wind — For other uses, see Solar wind (disambiguation). The solar wind is a stream of charged particles ejected from the upper atmosphere of the Sun. It mostly consists of electrons and protons with energies usually between 1.5 and 10 keV. The stream of …   Wikipedia

• Mathematics and Physical Sciences — ▪ 2003 Introduction Mathematics       Mathematics in 2002 was marked by two discoveries in number theory. The first may have practical implications; the second satisfied a 150 year old curiosity.       Computer scientist Manindra Agrawal of the… …   Universalium

• Uranus — This article is about the planet. For other uses, see Uranus (disambiguation). Uranus   …   Wikipedia

• Maunder Minimum — The Maunder minimum in a 400 year history of sunspot numbers The Maunder Minimum (also known as the prolonged sunspot minimum) is the name used for the period roughly spanning 1645 to 1715 when sunspots became exceedingly rare, as noted by solar… …   Wikipedia

• Atmosphere of Uranus — The atmosphere of Uranus, like that of Neptune, is markedly different from those of the larger gas giants, Jupiter and Saturn. While still composed primarily of hydrogen and helium, it possesses a higher proportion of volatiles (dubbed ices )… …   Wikipedia

• solar cycle — Astron. the variation of sunspots, prominences, flares, and other solar activity through an 11 year cycle. Also called solar activity cycle. Cf. sunspot cycle. * * * Period in which several important kinds of solar activity repeat, discovered in… …   Universalium

• Anders Celsius — Infobox Scientist name = Anders Celsius image width = 300px caption = Anders Celsius. Portrait by Olof Arenius birth date = birth date|1701|11|27|mf=y birth place = Uppsala, Sweden death date = death date and age|1744|04|25|1701|11|27|mf=y death… …   Wikipedia