Auroras are natural lights that appear as bright, swirling curtains in the night sky, displaying a variety of colours such as blue, red, yellow, green, and orange. These lights are typically seen around the poles in both the northern and southern hemispheres throughout the year but can sometimes extend to lower latitudes. The northern lights are called the Aurora Borealis, while the southern lights are known as the Aurora Australis.

Reasons for the Occurance of the Aurora

• Auroras occur due to activity on the Sun’s surface. The Sun continuously emits a stream of charged particles, primarily electrons and protons, along with magnetic fields known as the solar wind. As the solar wind approaches Earth, it is deflected by the planet’s magnetic field, which acts as a protective barrier.
• However, some charged particles become trapped in the magnetic field and travel along magnetic field lines near the north and south poles into the Earth’s upper atmosphere.
• These particles then interact with other gases in the atmosphere, producing small flashes that light up the night sky. When solar wind particles collide with oxygen, green light is produced, while interaction with nitrogen generates blue and purple hues.
• When the solar wind is particularly strong, auroras can extend to the midlatitudes. This happens when increased activity on the Sun’s surface leads to solar flares and coronal mass ejections (CMEs), which are additional bursts of energy in the solar wind.
•  In such cases, the solar wind is so strong that it can cause a geomagnetic storm, a temporary disturbance of the Earth’s magnetic field. During a geomagnetic storm, auroras can be observed in the middle latitudes.

NASA explains that solar storms erupt when the Sun unleashes powerful explosions called solar flares. These flares hurl intense bursts of energy particles towards Earth. These flares also release a type of high-energy radiation called ionized radiation. When this radiation interacts with Earth's atmosphere, it can create temporary magnetic fields.

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