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THE ELEMENTS OF NEAR-EARTH SPACE
Pages 12-33

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From page 12... ... These fields are sometimes concentrated in sunspots or complexes of sunspots forming active regions. Active regions are the usual sites of flares, which may occur when their complicated magnetic fields are suddenly rearranged. Read the entire page →
From page 13... ... Driven by the motions of the ionized gases beneath the visible surface, the North and South poles of the solar magnetic field reverse approximately every eleven years around sunspot number maximum. As a result, there is a roughly 22 year cycle in the Sun's magnetic "polarity," with the North or South magnetic pole in the northern hemisphere of the Sun during alternate sunspot maxima. Read the entire page →
From page 14... ... In general, the sizes, shapes, and distributions of coronal holes change over the solar cycle, with the largest coronal holes appearing around sunspot minimum when the coronal magnetic field has a simple configuration. The highest-speed solar wind streams observed at the Earth are often associated with these large coronal hole sources. Read the entire page →
From page 15... ... The interplanetary current sheet shape appears like a twirling ballerina's skirt when the solar dipole magnetic field has an axis different from the solar rotation axis (from: Lund Space Weather and AI Center, Lund University, Sweden) Read the entire page →
From page 16... ... This interconnection allows transfer of energy from the solar wind to the magnetosphere and ionosphere, as well as entry of charged particles from interplanetary space. The amount of interconnection is greatest when the interplanetary magnetic field has a southward direction. Read the entire page →
From page 17... ... Ionized atmospheric gases at high altitudes can be energized and transported around by a variety of processes that are still under study. The ions and electrons in the magnetosphere carry electrical currents that produce deviations in the magnetic field measured on the ground as well as in space. Read the entire page →
From page 18... ... , the density is down to 1/100 to 1/1000 times the density at the shuttle orbit. However, these densities can increase by more than ten times when the upper atmosphere is heated by strong solar ultraviolet radiation at solar maximum or by processes occurring during disturbed space weather. Read the entire page →
From page 19... ... The cosmic rays produced within the solar system sometimes make up the dominant contribution near Earth. Although Earth's magnetic field acts like a shield, deflecting all but the fastest of these particles, even low-energy cosmic rays reach low altitudes in the polar regions where the planet's magnetic field interconnects with the interplanetary field. Read the entire page →
From page 20... ... Space Weather: A Research Perspective The heliosphere is a bubble, formed by the expanding solar wind, in the material between the stars (from: NASA's Solar Connections home page) Read the entire page →
From page 21... ... file:///S\|/SSB/sunschem.jpg file:///S\|/SSB/sunschem.jpg [6/25/2003 4:36:23 PM] Read the entire page →
From page 22... ... file:///S\|/SSB/cabbage.gif file:///S\|/SSB/cabbage.gif [6/25/2003 4:36:29 PM] Read the entire page →
From page 23... ... file:///S\|/SSB/stone_f2.gif file:///S\|/SSB/stone_f2.gif [6/25/2003 4:36:34 PM] Read the entire page →
From page 24... ... file:///S\|/SSB/solarnew.gif file:///S\|/SSB/solarnew.gif [6/25/2003 4:36:37 PM] Read the entire page →
From page 25... ... file:///S\|/SSB/earthmag.gif file:///S\|/SSB/earthmag.gif [6/25/2003 4:36:46 PM] Read the entire page →
From page 26... ... file:///S\|/SSB/spweamag.gif file:///S\|/SSB/spweamag.gif [6/25/2003 4:36:48 PM] Read the entire page →
From page 27... ... file:///S\|/SSB/magspher.jpg file:///S\|/SSB/magspher.jpg [6/25/2003 4:36:52 PM] Read the entire page →
From page 28... ... file:///S\|/SSB/dungey.gif file:///S\|/SSB/dungey.gif [6/25/2003 4:36:57 PM] Read the entire page →
From page 29... ... file:///S\|/SSB/mh_new_r.gif file:///S\|/SSB/mh_new_r.gif [6/25/2003 4:37:04 PM] Read the entire page →
From page 30... ... file:///S\|/SSB/atmosph.gif file:///S\|/SSB/atmosph.gif [6/25/2003 4:37:08 PM] Read the entire page →
From page 31... ... file:///S\|/SSB/ps_cosmi.gif file:///S\|/SSB/ps_cosmi.gif [6/25/2003 4:37:12 PM] Read the entire page →
From page 32... ... file:///S\|/SSB/cr_ssn.gif file:///S\|/SSB/cr_ssn.gif [6/25/2003 4:37:15 PM] Read the entire page →
From page 33... ... file:///S\|/SSB/domain.jpg file:///S\|/SSB/domain.jpg [6/25/2003 4:37:19 PM] Read the entire page →

From page 12...

... These fields are sometimes concentrated in sunspots or complexes of sunspots forming active regions. Active regions are the usual sites of flares, which may occur when their complicated magnetic fields are suddenly rearranged.

THE ELEMENTS OF NEAR-EARTH SPACE Pages 12-33

THE ELEMENTS OF NEAR-EARTH SPACE
Pages 12-33