Who does not love to watch natural glimmering light show in the sky fill with tiny stars during dark, shivering midnights? There is no doubt that, seeing aurora is a popular wish in most of "Bucket lists".
Brief:
Aurora borealis (northern lights) or aurora australis (southern lights) or aurora Polaris (polar lights), those all names are referred to this alluring natural phenomenon. Due to two main reasons seeing aurora is ‘little bit’ a rare incident. Aurora is not visible to everywhere in the world. The auroral band spread across the high-latitude regions (i.e., Canada, Norway, Australia, Finland, Iceland, Greenland) around Arctic and Antarctic. There is no special season since the aurora is almost always happens. But you cannot see them every time. To see aurora, you need a dark, clear night without clouds and light pollution. Northern lights are visible from late August to early April anytime during dark hours. Southern lights can view during fall and winter months, which stretch from March through September.
Science behind this aurora Phenomenon
Auroral Colors
The colors in the aurora differ from each other according to give off gas in earth’s atmosphere.
- Green Aurora: The most common auroral colour. When the solar wind hits millions of oxygen atoms in the Earth’s atmosphere at the same time, it excites their electrons for a time and then they decay back to their original state, they emit the green hue.
- Red Aurora: The red light we sometimes see is also reasoned by oxygen atoms. These particles are higher up in the atmosphere and are subject to a lower energy red light emission. The red colour is always there, but our eyes are five times less sensitive to red light than green, so we can’t always see it.
- Purple Aurora: Nitrogen is a main gas element in Earth’s atmosphere. When the charged particles from the solar wind hit nitrogen atoms to excite them. Once the nitrogen atoms begin to decay, they emit a purple hue.
Red and purple are rare to see, and usually only happens during a particularly active display.
