Science behind Northern Lights

The northern lights are also known as the polar lights. These are the shafts or curtains of colourful lights that are visible in the night sky in the regions located close to the magnetic poles. The scientific names of the northern lights and the southern lights are aurora borealis and aurora australis respectively. The basic process used for the formation of northern lights includes the collision of charged sun particles with the neutral atoms present in the earth’s atmosphere. This leads to the emission of a huge amount of energy in the form of light. The distance at which the northern lights have appeared closest to the earth is equal to 80 km.

The polar lights are formed when the high energy charged particles of the sun escape the sun’s corona, travel through the earth’s atmosphere, and face a series of interactions with the magnetic field of the earth. The corona is the outermost layer of the sun and is considered to be one of its hottest regions. The extensive heat of the sun’s corona region vigorously vibrates the hydrogen and helium atoms contained by the sun. This leads to the discharge of millions of electrons and protons in space. These protons and electrons blasted by the sun are polarised and contain a significant amount of charge on them. They move freely in space at a high velocity and are mainly responsible for the creation of the northern lights. The high velocity of the particles helps them escape the sun’s gravitational field and combine with each other to form a cluster of electrically charged gas known as plasma. The gale of plasma is typically known as the solar wind. The solar wind moves towards the earth’s surface at a velocity of approximately one million miles per hour. The earth’s strong magnetic field or the magnetosphere acts as a shield and resists the solar wind from entering the earth’s environment. The photons are the high energy particles that tend to release their energy in the form of light. Thereby, producing multiple light waves in the earth’s upper atmosphere, which almost resembles a waterfall of light particles that follow a magnetic field line. This curtain of multi-coloured lights is seen from the earth’s surface and are known as auroras.

studiousguy.com