red flame; crimson blaze
Literary or poetic term for a vividly red flame. Not an everyday word for fire.
A crimson blaze shot up as if scorching the night sky.
solar prominence
Astronomy term for a large, bright feature extending outward from the Sun's surface.
During the total solar eclipse, solar prominences were observed at the Sun's edge.
Katakana loanword for solar prominence, more common in modern astronomy contexts than 紅炎.
Standard kanji spelling for both senses.
Variant kanji form using 焔 (flame); less common than 紅炎.
Compound of 紅 (crimson, deep red) and 炎 (flame, blaze). The astronomical sense is a calque from English 'solar prominence', using the same kanji to evoke a reddish flame-like structure on the Sun.