Earth acts like a big magnet due to its components namely, nickel, silicon,iron and other metallic substances. Inside the earth there is a process calledconvection, it is the movement of the metals which has charges; if thesecharges move it creates a magnetic field.
The Sun continuously burns with millions of fusion reactions every second.These reactions are at very high temperature which will transfer to the gassessurrounding the star and create plasma. In analogy, when a volcano erupts, itreleases tons of ash and pyroclastic materials into the sky and its neighboringplaces.
The same things happens on the Sun, it blasts plasma into the solarsystem and the speed of its particles depends on how active the sun.Earth’s magnetic field provides a barrier to the solar wind, called themagnetosphere. The solar wind interacting with the Earth’s magneticfield transfers some of its energy into the upper atmosphere in the Polar Regions.The auroras that are visible at high latitudes are one manifestation of thistransfer. But it also heats up atmospheric ions enough that they escape up outof the poles, forming Earth’s “polar ion outflows”(Schirber, 2011).In a planet or a moon without a magnetic field, the solar wind will hit itdirectly.
That’s what happens on the moon. All of the charged particles areconstantly hitting the surface that faces the Sun. If a planet has a magnetic fieldlike Jupiter and Earth, the solar wind neither will nor hit the planet directly or inother words it will be deflected.The planets near to Earth like, Mars and Venus, have no oceans or lakes.Researchers and experts believe that they were blown dry or get evaporatedby the solar wind.
The solar wind basically barrels straight into the upperatmosphere and scoops up ions and carries them into space. Earth hasescaped this phenomenon because of its strong magnetic field which deflectsthe wind.REFERENCE:http://www.cosmos4kids.com/files/sol