also: きょくこう
noun
aurora; northern lights; southern lights
Scientific and general term for the aurora. オーロラ is more common in everyday speech.
極光は北極や南極の近くでよく見られる。
The aurora is often seen near the North and South Poles.
昨夜、北海道で美しい極光が観測
A beautiful aurora was observed in Hokkaido last night.
More common everyday word for the aurora. 極光 is more formal or scientific.
From 極 (pole) + 光 (light). The reading きょっこう is a contraction of きょくこう.