the brightest star in visible, is easily seen—a blue-white dot in the upper center of the photograph, marked with the Greek symbol alpha. 
    The Great Nebula is the bright yellow region in the lower right. In this area ultraviolet radiation from clusters of hot young stars has heated the clouds of hydrogen and helium. Around the nebula are immense clouds of cooler material (red-orange in this image) that consist primarily of hydrogen and helium. Stars are currently forming in these clouds.