Aquarius constellation Reference Libraries
Saturn Nebula -- The layers of the Saturn Nebula give a complex picture of how this planetary nebula was created. The above picture, taken in April 1996 and released last week, allows a better understanding of the mysterious process that transformed a low-mass star into a white dwarf star. A computer model indicates that the central star of NGC 7009 first expelled the green gas that now...
Dumbbell Nebula -- Discovered by Charles Messier in 1764. 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. We happen to see this one approximately from its equatorial plane (approx. left-to-right in our image); from...
- A Roman unit of weight, 1⁄1728 of a pound.
- A weight of four grains used in weighing gold and precious stones; a carat.
- In anatomy, a formation suggesting a husk or pod.
- The lowest unit in the Roman coinage, the twenty-fourth part of a solidus.
- A coin of base silver of the Gothic and Lombard kings of Italy.