The Nebulas of Spiral Galaxy M33

About This Photograph

Here is a unique photograph of spiral galaxy M33. Narrow-band exposures through hydrogen, sulfur, and oxygen filters were "continuum subtracted" with exposures through red and blue filters to remove almost all of the light from the stars of the galaxy, leaving only its beautiful collection of nebulas. These are vast clouds of gas lit up by newborn stars, not unlike our Milky Way's own such treasures. These nebulas generally trace the spiral arms of the galaxy, and increase in density toward the center due to the increased density of gas. The colors represent the different elements present: red for hydrogen, yellow for sulfur, and blue for oxygen.