APOD - The Horsehead and Flame Nebulas
Astronomy Picture of the Day Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer. 2025 September 2 The Horsehead and Flame Nebulas Image Credit & Copyright: Daniel Stern Explanation: The Horsehead Nebula is one of the most famous nebulae on the sky. It is visible as the dark indentation to the orange emission nebula at the far right of the featured picture . The horse-head feature is dark because it is really an opaque dust cloud that lies in front of the bright emission nebula . Like clouds in Earth's atmosphere , this cosmic cloud has assumed a recognizable shape by chance. After many thousands of years , the internal motions of the cloud will surely alter its appearance. The emission nebula 's orange color is caused by electrons recombining with protons to form...
