The Science behind Aurora
Aurora, also known as polar lights, northern lights, or southern lights, is a natural light display in the night sky commodiously observed in high-latitude regions. Millions have experienced the majestic wonder of the Aurora since the dawn of time. It looks too beautiful to be real, but what many people compare to a Vegas light show is a result of natural science, as is almost everything else in our world.
Image courtesy of The Telegraph.
The Science behind Aurora
Aurora's beauty is remarkably a result of a collision between charged particles released by the sun and gaseous particles in the Earth's atmosphere. The colour variations are dependant on the type of gas particles that are colliding.
The most common auroral colour is pale green, caused by oxygen molecules located about 60 miles above the Earth's surface. All-red auroras, which are incredibly tenuous, are caused by high-altitude oxygen, transpiring at a distance of up to 200 miles above the Earth's surface.
But you may be wondering, how does this happen - the sun is millions of miles away? How can particles collide from that far? The sun is extremely powerful, so its effects extend far beyond its visible surface. Great storms on the sun, known as solar winds, send gusts of charged solar particles plunging across space. If the particle stream traverses Earth, its magnetic field and atmosphere react.
In summary, when charged particles from the sun collide with atoms in the Earth's atmosphere, they induce electrons to move to a higher energy state. After the electrons drop back to a lower energy state, they release a photon: light.
The Science behind Aurora (Discover the World).
Does Aurora only occur in the North?
Despite the common misconception, Aurora can actually be seen in both the northern and southern hemispheres, in an intermittently shaped ellipse centred over each magnetic pole. However, it is predominantly seen in the northern hemisphere. In the north, this magnificent phenomenon is called “Aurora Borealis”, which means “dawn of the north”, and it is called “Aurora Australis” (“dawn of the south”) in the south. Interestingly, scientists have discovered that in most cases, the northern and southern auroras look like mirror images that occur at the same time, with similar shapes and colours.
Northern Lights. (n.d.). Northern Lights Centre.
Imster, E. (2017). What causes the aurora borealis? EarthSky Communications Inc.
The Northern Lights. (n.d.). Discover the World. https://www.discover-the-
Article Author: Risheena Banerji
Article Editor: Olivia Ye