Title:[0274] Clouds of stars and dust in Sagittarius Caption:Around the center of our Galaxy are found huge numbers of stars that are faint and often billions of years old, as ancient as the Galaxy itself. These stars are seen with the unaided eye as the star clouds of the southern Milky Way, especially rich in Sagittarius. Our line of sight is strongly affected by dust, which reveals itself by both dimming the starlight passing through it and by selectively removing the blue component, changing the color to a deeper yellow. Appropriately, near the center of the picture, is a region known as Baade's Window after the astronomer who selected this part of the Milky Way for special study. Copyright:(c) 1987 Royal Observatory Edinburgh Credit:D. F. Malin

Title:[0275] NGC 6522, gamma Sagittarii and Baade's Window Caption:The German-American astronomer Walter Baade selected a region of the crowded star fields in Sagittarius where he believed the Galactic dust obscuration was both uniform and minimal. He used this line of sight to establish the distance to the Galactic center, using variable stars as his yardstick. The distribution of these stars along this chance line of sight seems to peak at a distance of about 30,000 light years, which can be taken as the distance to the unseen Galactic center. This part of the sky, around the globular cluster NGC 6522, is now known as Baade's window; the brightest star in the photograph is gamma Sagittarii, a deep yellow naked eye star of about third magnitude. It is in the foreground at a distance of about 100 light years. Copyright:(c) 1987 ROE/Anglo-Australian Telescope Board, photograph by David Malin Credit:D. F. Malin