M33, NGC 598

This image of the Triangulum Galaxy was taken at the National Science Foundation's 0.9-meter telescope on Kitt Peak with the NOAO Mosaic CCD camera. Also known as M33, the Triangulum Galaxy is part of the Local Group of galaxies, which includes the Andromeda Galaxy (M31) and our galaxy, the Milky Way. M33 is over thirty thousand light-years across, and more than two million light-years away. The optical data in this image show the many stars within the galaxy as well as reddish star forming regions that are filled with hot hydrogen gas. Hot, massive stars which recently formed in M33 give the galaxy its bluish color. The reddish areas are nebulae in the galaxy in which stars are rapidly forming. The color image was generated by combining images taken through four filters (B, V, I and Hydrogen-alpha). The image is one square degree in field of view, roughly five times the size of the Moon. We also have an image of M33 combined with radio data from the Very Large Array telescope and the Westerbork Synthesis Radio Telescope.