... Hiorter and Celsius note that the polar aurora is accompanied by a disturbance of the magnetic needle. ... Richard Carrington in England observes a violent and rapid eruption near a sunspot; 17 hours later a large magnetic storm begins. ... Using it he observes a solar flare and confirms the connection between flares and magnetic storms. ... Explorer 1, launched by the US January 31, observes the radiation belt; Explorer 3, launched in March, comes up with the first clear evidence for its existence....
The "ring of fire" seen by satellite cameras around the polar caps (picture below) is probably created by electrons leaking from the tail's plasma sheet, whose magnetic field lines form a somewhat imperfect trap. ... One possible explanation involves the close association between auroral arcs and electric currents which flow along field lines between the ionosphere and distant space ( Birkeland currents ). ... That produces an extra resistance to the flow of current. ...
Atlas . Saturn XV - 1980S28 . Atlas, the second of Saturn's known satellites, orbits near the outer edge of the A-ring and is about 40 by 20 kilometers (25 by 15 miles) in size. It is probably a shepherd satellite for Saturn's A-ring. Atlas was discovered by R. Terrile in 1980 from photographs taken by Voyager during its encounter with Saturn. Atlas Statistics . ... Mean density (gm/cm^3) . ... Rotational period (days) . Orbital period (days) . ... Credit: Calvin J. Hamilton) . ...