Portuguese navigator Fernando de Magellan and his crew had plenty of time to study the southern sky during the first circumnavigation of planet Earth. As a result, two fuzzy cloud-like objects easily visible for southern hemisphere skygazers are known as the Clouds of Magellan. Of course, these star clouds are now understood to be dwarf irregular galaxies, satellites of our larger spiral Milky Way galaxy. An alluring sight in dark southern skies, the Large Magellanic Cloud (LMC) pictured above is only about 180,000 light-years distant in the constellation Dorado. Spanning about 15,000 light-years or so, it is the most massive of the Milky Way's satellite galaxies and is the site of the closest supernova in modern times. The prominent red knot on the left is 30 Doradus, or the Tarantula Nebula, a giant star-forming region in the Large Magellanic Cloud, particularly well visible here because of the use in the final images stack of a narrow band filter that transmits only the red light of hydrogen atoms. (Text adapted from APOD). More than 73 hours of total exposures went into this 4 panels mosaic covering about 140 square degrees of sky. Pentax 67 EDIF 300mm f/4 - FLI Proline 16803 - Ha (1200m) OIII (820m) L (960m) R (470m) G (480m) B (490m) - Warrumbungle Observatory, Coonabarabran, NSW, Australia
Portuguese navigator Ferdinand Magellan and his crew had plenty of time to study the southern sky during the first circumnavigation of planet Earth. As a result, two celestial wonders easily visible for southern hemisphere skygazers are known as the Clouds of Magellan. These cosmic clouds are now understood to be dwarf irregular galaxies, satellites of our larger spiral Milky Way Galaxy. The Small Magellanic Cloud actually spans 15,000 light-years or so and contains several hundred million stars. About 210,000 light-years away in the constellation Tucana, it is more distant than other known Milky Way satellite galaxies, including the Canis Major and Sagittarius Dwarf galaxies and the Large Magellanic Cloud. This sharp image also includes two foreground globular star clusters NGC 362 (bottom right) and 47 Tucanae. Spectacular 47 Tucanae is a mere 13,000 light-years away and seen here to the left of the Small Magellanic Cloud (text adapted from APOD). Pentax 67 EDIF 300mm f/4 - FLI Proline 16803 - Ha (160m) OIII (240m) L (100m) R (40m) G (40m) B (40m) - Warrumbungle Observatory, Coonabarabran, NSW, Australia
At the top of this skyscape, Centaurus A (NGC 5128) seems to be a fantastic jumble of old yellow stars, young blue star clusters, and imposing dark dust lanes. Spanning over 60,000 light-years, the peculiar elliptical galaxy is apparently the result of a collision of two otherwise normal galaxies. The left over cosmic debris is steadily being consumed by a black hole with a billion times the mass of the Sun which lies at the center of Centaurus A. It's likely that such black hole central engines generate the radio, X-ray, and gamma-ray energy radiated by Centaurus A and other active galaxies. For an active galaxy Centaurus A is close, a mere 10 million light-years away, and is well-studied by earthbound astronomers. At the bottom of this image, globular star cluster Omega Centauri (NGC 5139) is some 15,000 light-years away and 150 light-years in diameter. Packed with about 10 million stars much older than the Sun, Omega Cen is the largest of 200 or so known globular clusters that roam the halo of our Milky Way galaxy. Though most star clusters consist of stars with the same age and composition, the enigmatic Omega Cen exhibits the presence of different stellar populations with a spread of ages and chemical abundances. In fact, Omega Cen may be the remnant core of a small galaxy merging with the Milky Way (text adapted from APOD). Pentax 67 EDIF 300mm f/4 - FLI Proline 16803 - L (160m) R (40m) G (40m) B (40m) - Warrumbungle Observatory, Coonabarabran, NSW, Australia
