Rules wouldn't exist if one couldn't break them. The never altered blurb pic blurb format of the last 0.2k posts will have a one post sabbatical. I won't get back a decent astro photo rig again until late next year, so in response to that depressive thought, here are a few more images taken last weekend. The Venera 3 was originally claimed to have survived it's initial impact on Venus, but as it was only pressure rated to 25 atmospheres and the actual surface pressure is now estimated to be around 90 - it wouldn't have functioned anyway. The Americans claimed at the time that Venera 3 failed before descent - a few years on the Soviets agreed.
47 Tuc
NGC 104, better known as 47 Tucanae, is the second largest and second brightest globular cluster in the skies, outshone only by another southern globular NGC 5139. First cataloged as a deep sky object in 1751 by Abbe Lacaille as Lac I.1, the stars of 47 Tucanae are spread over a volume nearly 120 light years across. At their distance of 13,400 light years, they still cover an area of the sky of about the same apparent diameter as the full moon, about 30 minutes of arc. Globular cluster 47 Tucanae is approaching us at roughly 19 km/s.
Omega Centauri
NGC 5139 (Lacaille I.5, Omega Centauri) - was discovered by Edmond Halley in 1677. This is the biggest of all globular clusters in our galaxy. With its about 5 million solar masses, it is about 10 times as massive as other big globulars, and has about the same mass as the smallest whole galaxies. It is also the most luminous Milky Way globular, and the brightest globular cluster in the sky.
Dumbbell Nebula
NGC 6853 - The Dumbbell Nebula M27 was the first planetary nebula ever discovered. On July 12, 1764, Charles Messier discovered this new and fascinating class of objects, and describes this one as an oval nebula without stars. The name "Dumb-bell" goes back to the description by John Herschel, who also compared it to a "double-headed shot." As for a lot of planetary nebulae, the high energy (mostly non visible) radiation produced by the central star is released by excitation in visible light emitted in one spectral line only- here at 5007 Angstrom.
Omega Nebula
NGC 6618 (aka Omega Nebula, M17, Swan Nebula, Horseshoe Nebula) was discovered and cataloged by Philippe Loys de Chéseaux before 1745 but wasn't well known until Charles Messier independently rediscovered it and cataloged it in 1764. The mass of the gas in the Omega nebula has been estimated to amount about 800 times that of the Sun, enough for forming a conspicuous cluster, and a good deal more than that of the Orion nebula M42. While the bright nebula seems to be roughly 15 light years in extension, the total gaseous cloud, including low-luminosity material, seems to extend to at least 40 light years. Distance estimates are spread over a wide range, but modern values are between 5,000 and 6,000 light years- a little less than that of its apparent neighbor the Eagle nebula (M16) - apparently, these two star forming regions are indeed close together, in the same spiral arm (the Sagittarius or Sagittarius-Carina arm) of the Milky Way galaxy.
47 TucNGC 104, better known as 47 Tucanae, is the second largest and second brightest globular cluster in the skies, outshone only by another southern globular NGC 5139. First cataloged as a deep sky object in 1751 by Abbe Lacaille as Lac I.1, the stars of 47 Tucanae are spread over a volume nearly 120 light years across. At their distance of 13,400 light years, they still cover an area of the sky of about the same apparent diameter as the full moon, about 30 minutes of arc. Globular cluster 47 Tucanae is approaching us at roughly 19 km/s.
Omega CentauriNGC 5139 (Lacaille I.5, Omega Centauri) - was discovered by Edmond Halley in 1677. This is the biggest of all globular clusters in our galaxy. With its about 5 million solar masses, it is about 10 times as massive as other big globulars, and has about the same mass as the smallest whole galaxies. It is also the most luminous Milky Way globular, and the brightest globular cluster in the sky.
Dumbbell NebulaNGC 6853 - The Dumbbell Nebula M27 was the first planetary nebula ever discovered. On July 12, 1764, Charles Messier discovered this new and fascinating class of objects, and describes this one as an oval nebula without stars. The name "Dumb-bell" goes back to the description by John Herschel, who also compared it to a "double-headed shot." As for a lot of planetary nebulae, the high energy (mostly non visible) radiation produced by the central star is released by excitation in visible light emitted in one spectral line only- here at 5007 Angstrom.
Omega NebulaNGC 6618 (aka Omega Nebula, M17, Swan Nebula, Horseshoe Nebula) was discovered and cataloged by Philippe Loys de Chéseaux before 1745 but wasn't well known until Charles Messier independently rediscovered it and cataloged it in 1764. The mass of the gas in the Omega nebula has been estimated to amount about 800 times that of the Sun, enough for forming a conspicuous cluster, and a good deal more than that of the Orion nebula M42. While the bright nebula seems to be roughly 15 light years in extension, the total gaseous cloud, including low-luminosity material, seems to extend to at least 40 light years. Distance estimates are spread over a wide range, but modern values are between 5,000 and 6,000 light years- a little less than that of its apparent neighbor the Eagle nebula (M16) - apparently, these two star forming regions are indeed close together, in the same spiral arm (the Sagittarius or Sagittarius-Carina arm) of the Milky Way galaxy.
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