Solar wind

An experiment for the study of the solar wind. The solar wind gel is aligned by Aldrin (photo: Apollo 11, )

That Solar wind a river of charged particles is, from that into the universe flows. In particular also the wrong term becomes occasional in the press Sun-deaf used, which in particular during the reporting to Genesis probe the case was.

Emergence and composition

The solar wind exists mainly out and as well as out (Alpha particle); other atomic nuclei and did not ionize (electrically neutral) atoms are present only to small extent. Although the solar wind originates from the outside layers of the sun, the solar wind does not reflect the element frequency of these layers of the sun accurately again, there by cracking processes (FIP effect) some elements in the solar wind to be enriched and/or diluted. Inside the sun the element frequentnesses became by taking place the there changed. Since the outside layers of the sun are however not mixed with the internal layers, their composition corresponds still to the composition of the Urnebels, from which the solar system formed. The study of the solar wind is therefore also interesting, around both on the chemical composition and on those the Urnebels.

The sun loses about 1 million tons of their mass by the solar wind per second. One differentiates between the slow and the fast solar wind. The speed of the slow solar wind is with approximately 400 kilometers per second, the fast solar wind, because of that koronalen Holes withdraws, reaches 800-900 kilometers per second. At perigee the solar wind has one Density of approx.. 5·10⁶ Particle per m³.

Effects of the solar wind

There the solar wind out particle exists, adjusts it Plasma , both the that Magnetic field the sun like also that that deforms. The terrestrial magnetic field holds the particle shower to the largest part of the earth. Only with a strong solar wind the particles can into the high layers that penetrate and there Polar lights cause, just like on other planets with a magnetic field. Strong solar winds knew also influence on the propagation of electromagnetic waves and among other things that Short wave radio and communication also Satellites disturb.

Those supply a clearly visible sign for the existence of the solar wind : Comet tails show always away from the sun, because the gas and dust particles, which form the coma and the tail, are drug along by the solar wind.

The solar wind extends far to over the outside planet courses. It drives that interstellar gas from that outside and a kind forms blister in the universe, which Heliosphaere one calls. The border of the heliosphaere, at which the particles of the solar wind are braked, is called Heliopause. It is often regarded as the border of the solar system. The exact distance is not well-known, observations of the space probe Voyager 2 it gives reason to the acceptance that itself the heliopause at approximately the quadruple distance of the finds.

Discovery and research

Already the researcher observed Richard Carrington a connection between Sonnenflares and shifted temporally terrestrial magnetic field towers, which - although at that time unexplainably - an early indication for the existence of the solar wind was. At the beginning of of the the Norwegian represented Kristian Birkeland the view, the polar lights by particle streams by the sun were released. Its idea was however just as little seriously taken, as those of the German physicist Ludwig Biermann, which accepted a "solar particle radiation", around the direction that explain to be able. It had noticed to astronomers that the comet tails were arranged not accurately away from the sun, but exhibited a small angle in addition. Biermann explained this characteristic by the movement of the comet in itself a likewise moving particle stream, to a certain extent a lateral leeways by those . E.N. Parker has the English designation solarly wind introduced and one magnetohydrodynamische Theory for the description of the solar wind suggested.

The existence of the solar wind could only by the Soviet Lunik 1 and by the American Space probe Marine 2 on their way to to be experimentally confirmed. A further milestone in the study of the solar wind were those Solar wind gel which with exception of Apollo 13 and 17 with all moon-landings were set up and data over the isotope frequentnesses of the noble gases , and in the solar wind supplied. Many further missions contributed to understand the solar wind. The space probes Pioneer 10/11, Voyager 1/2 and those Ulysses mission data of the solar wind supplied outside of the earth orbit, during of Helios 1/2 and those Marine- and Pion estimation ions to the Venus as well as Russian VeGaProbes data of within the earth orbit supplied. IMP 1-8, AIMP 1/2, ACE, ISEE 1-3 probes as well as the sonnenobservatorium SOHO and the space probe Wind solar wind data supplied to perigee. The Ulysses mission supplied also data over the solar wind outside of that Ecliptic. In the year those became Genesis mission started with which highly pure crystals in the one that Point of lying rank L1 of the earth sun system the solar wind were suspended and afterwards for investigation to the earth to be returned should. Mission failed however with their conclusion in year 2004, since the cap, in which the solar wind particles should be transported to the earth, was braked not as planned by a parachute and caught then by a helicopter, but smashed on the soil, since the parachute had not opened.

There are efforts, the solar wind assistance of Sonnensegeln to use to the drive from spacecraft to.

Literature

• Kevin Ivory: Suprathermi electrons in the solar wind as indicators of unusual magnetic field structures of the internal heliosphaere: Thesis at the mathematical-scientific faculty of the George August university to Goettingen, 1998: Article on-line on the document server of the state and university library of Lower Saxony Goettingen available: HTTP://webdoc.gwdg.de/diss/1999/ivory/phd_ivory.pdf
• Picture of the science: 11 August 2005: As the solar wind whirls the shield of the earth in disorder: Axel Tillemans: Article in the on-line offer of Picture of the science HTTP://www.science.de/wissen/news/256293.HTML

Web on the left of

• Homepage of the genesis mission (English)
• more spaceweather.com - space weather side (English)
• Scientific data to the solar wind (English)