Spaced out Sundays

In this picture, the disk is the green-colored oval near the center. Radiation from the hot star is heating up the disk, causing matter to dissipate, like steam evaporating from the surface of boiling water. A strong 'stellar wind, ' a stream of particles moving at 4, 500 to 8, 900 miles per hour (7, 200 to 14, 400 kilometers per hour), is propelling the material away from the disk. The material is glowing because it is being energized by radiation from the hot star.