The effect of solar wind?
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Answer:
The easiest way to observe the effects of solar winds is to watch a comet as it approaches. You can easily see, with the naked eye, as the comet approaches our sun, it's tail seems to trail out behind it as if it were flying fast, but as the comet returns from the suns orbit the tail is now trailing in the same direction the comet is flying, well thats because its not really a tail, but it is part of the comet being burned off by the solar wind of our sun, this tail will always face away from the sun. This is one effect of solar winds.
Effects on the planets
Mercury, the nearest planet to the Sun, bears the full brunt of the solar wind. Any atmosphere that this moon-like world may once have had has long been swept away, leaving its surface bathed in radiation.
Mars is larger than Mercury and four times further from the Sun, and yet even here it is thought that the solar wind has stripped away up to a third of its original atmosphere, leaving a bale 100 times thinner than our own.
Venus, the nearest planet to the Earth, has an atmosphere 100 times thicker than our own. Modern space probes have discovered a comet-like tail that stretches back to the orbit of the Earth (Grünwaldt 1997.) The clouds on Venus are also being eroded by the solar wind.
Earth itself is protected from the solar wind by its magnetic field, which deflects charged particles. We only notice the solar wind when it is strong enough to deform this magnetic field, causing phenomena such as geomagnetic storms and the aurora.
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Variability and space weather
The solar wind is responsible for the overall shape of Earth's magnetosphere, and fluctuations in its speed, density, direction, and entrained magnetic field strongly affect Earth's local space environment. For example, the levels of ionizing radiation and radio interference can vary by factors of hundreds to thousands; and the shape and location of the geopause (Earth's bow shock wave in the solar wind) can change by several Earth radii, exposing geosynchronous satellites to the direct solar wind. These phenomena are collectively called space weather.
Both the fast and slow solar wind can be interrupted by large, fast-moving bursts of plasma called interplanetary coronal mass ejections, or ICMEs. ICMEs are the interplanetary manifestation of solar coronal mass ejections, which are caused by release of magnetic energy at the Sun. ICMEs are often called "solar storms" or "space storms" in the popular media. They are sometimes, but not always, associated with solar flares, which are another manifestation of magnetic energy release at the Sun. ICMEs cause shock waves in the thin plasma of the heliosphere, launching electromagnetic waves and accelerating particles (mostly protons and electrons) to form showers of ionizing radiation) that precede the ICME.
When an ICME impacts the Earth's magnetosphere, it temporarily deforms the Earth's magnetic field, changing the direction of compass needles and inducing large electrical ground currents in Earth itself; this is called a geomagnetic storm and it is a global phenomenon. ICME impacts can induce magnetic reconnection in Earth's magnetotail (the midnight side of the magnetosphere); this launches protons and electrons downward toward Earth's atmosphere, where they form the aurora.
ICMES are not the only cause of space weather. Different patches on the Sun are known to give rise to slightly different speeds and densities of wind depending on local conditions. In isolation, each of these different wind streams would form a spiral with a slightly different angle, with fast-moving streams moving out more directly and slow-moving streams wrapping more around the Sun. Faster-moving streams tend to overtake slower streams that originate westward of them on the Sun, forming turbulent corotating interaction regions that give rise to wave motions and accelerated particles, and that affect Earth's magnetosphere in the same way as, but more gently than, ICMEs.
Outer limits
The solar wind blows a "bubble" in the interstellar medium (the rarefied hydrogen and helium gas that permeates the galaxy). The point where the solar wind's strength is no longer great enough to push back the interstellar medium is known as the heliopause, and is often considered to be the outer "border" of the solar system. The distance to the heliopause is not precisely known, and probably varies widely depending on the current velocity of the solar wind and the local density of the interstellar medium, but it is known to lie far outside the orbit of Pluto.
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