The Blue Flame of Rigel and the Red Glow of Hydrogen Nebulae In the constellation Orion, the star Rigel illuminates the cosmos with its bright blue light, while the surrounding hydrogen nebulae emit a rich red glow. This image required 22 hours of exposure. It reveals the fine structures of gas and dust, creating a stunning contrast between the star's cool glow and the warm hues of the nebulae.