History of the solar wind

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History of the solar wind doesn't go so deeply into our past, but it is not that new as someone would say. The existence of particles flow from the Sun was suggested by British astronomer Richard C. Carrington (1859).  By the end of the 19th century seemed to be clear idea of connection between the solar activity and magnetic field disturbances on the Earth. But what was the carrier?

In 1910 British astrophysicist Arthur Eddington suggested indirectly existence of the solar wind in the article on Comet Morehouse.

The first person who has suggested ejected material from the Sun was Kristian Birkeland. He has displayed that the geomagnetic activity was produced by the particles coming from the Sun. In 1919 Frederick Lindemann suggested that quasi-neutral charged particles come from the Sun and are responsible for the non-recurrent magnetic storms at the Earth.

In 1950s Ludwig Biermmann got interested that no matter where the comet was heading, the cometary tail was always pointing from the Sun, which would agree with the theory of a continuous outflow from the Sun, unrelated to the large flares. 

Luna 1: replica
However, the first direct in-situ observations of the solar wind came from the Russian Lunik III and Venus I spacecraft in 1959, and its final proof was given by US Mariner II in 1962-1967.

Ulysses was launched in 1990 and its original name was Odysseus. It was joint mission of NASA and ESA. It made 3 observations of the Sun in 1994/1995, 2000/2001, and 2007/2008. I think that picture sometimes tell better than words:

NASA: Solar minimum vs. Solar maximum





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