Note: In addition to the obvious hypertext links embedded in this page, several of the images below are "clickable" for more information. Please experiment, as this site is under constant development.
Caption: This image shows the thousands of galaxies detected when the Hubble Space Telescope was used to take a very long ("deep") exposure of one patch of sky. The space between the galaxies comprises the "Intergalactic Medium."
Caption: Optical Photograph of the Grand-Design Spiral M51 and its companion. Note the H II Regions dotting the arms of M51 and the dust lanes apparent in both M51 and the "tail" to its companion. Click on the image for more on the ISM of spiral galaxies.
Caption: The edge-on spiral galaxy NGC xxxx. The dusty disk of the galaxy is evident as the dark band running along its length. The stellar bulge is obviously visible near the center of the galaxy. Click on the image for more on the vertical distribution of material in the ISM.
Image of Orion A here.
More photos of the Horsehead and Other Nebulae caption about H-alpha and extinction and NGC 2024.
