Spicule (solar physics)

Spicules (Latin Spiculum " top ", " skewer "; majority spicules ) are tube -like eruptive phenomena in the solar chromosphere and probably other stars. They were discovered in the solar eclipse in 1877 at the solar limb and appear as over quick, upward gas splashes. As was first recognized in 1950, it is extremely fast solar flow channels that focus particularly on sunspots. They are caused by the violent convection beneath the solar surface ( photosphere ), which transports the heat radiation from the solar interior to the outside.

The spicules have diameters of a few 100 up to 1,000 kilometers, can be around 10,000 km long and shoot with about 3,000 to 12,000 km / sec (?) High. Depending on the speed they fall after a few minutes in on itself.

Recent studies

Analysis with high-speed cameras have shown that there are on average about five spicules minutes. They begin as small tubes of rapidly ascending gas, but disappear when the gas has reached the highest point and falls back to the sun. The formation and the dynamics of spicules is in the details still unclear, but is related to violent upward shock waves and transparent magnetic fields. Its entirety causes the heating of the lower part of the corona. The temperature of the gas splashes is several million kelvins.

Angelo Secchis " burning prairie "

Very clearly intimated that he had discovered phenomenon Angelo Secchi SJ of the Vatican Observatory. He compared the case eclipses visible at the solar limb chromosphere with huge bush fires or burning prairie. The chromosphere is growing from a uniform lower layer ( ie, from the photosphere ) out and make an impression, as if constantly beat up flames.

The sun researcher Otto Kiepenheuer turns the whole ( relatively thin ) chromosphere as " spatter or spray of the surging photosphere - ocean " with its ever upward flowing granulation swirls before. As the light splash of the surf much higher speeds than develop the heavy waves of the sea, the spicules splashes are much faster than the flow processes in the much denser photosphere. This diagram corresponds essentially to the now well- predictable processes at shock fronts.