... Flame Nebula Close Up . ... 2.02.2007 . ... Also known as NGC 2024 , the nebula's suggestive reddish color is due to the glow of hydrogen atoms at the edge of the giant Orion molecular cloud complex some 1,500 light-years away. ... In this close-up view , a dark lane of absorbing interstellar dust stands out in silhouette against the hydrogen glow and actually hides the true source of the Flame Nebula's energy from optical telescopes. ... Publications with keywords: emission nebula - Orion . ...