Gamma Doradus variables are variable stars which display variations in luminosity due to non-radial pulsations of their surface. The stars are typically young, early F or late A type main sequence stars, and typical brightness fluctuations are 0.
This is a relatively new class of variable stars, having been first characterised in the second half of the s, and details on the underlying physical cause of the variations remains under investigation. We call these mysterious strangers Oscillating Blue Stragglers. We have to look at R Doradus! The visible magnitude of R Doradus varies between 4. With the exception of our own Sun, R Doradus is currently believed to be the star with the largest apparent size as viewed from Earth.
The stellar diameter of R Doradus could be as much as million kilometers. If placed at the center of the Solar System, the orbit of Mars would be entirely contained within the star.
Too cool…. Dorado contains a huge amount of deep sky objects very well suited for binoculars, small and large telescopes.
So many, in fact, our small star chart would be so cluttered that it would be impossible to read designations. In itself, it is an irregular dwarf galaxy, distorted by tidal interaction with the Milky Way and may have once been barred spiral galaxies. This unusually high velocity seems to imply that they are in fact not bound to the Milky Way, and many of the presumed effects of the Magellanic Clouds have to be revised. Be sure to explore the LMC for its own host of nebula and star forming regions.
Dorado is one of 12 southern constellations included by Petrus Plancius in his celestial globe of that were based upon the observations of Dutch explorers Pieter Dirkszoon Keyser and Frederick de Houtman. Dorado represents the tropical dwelling dolphinfish that Dutch navigators saw hunting flying fish during their voyages to the East Indies Southeast Asia.
Also known as mahi-mahi, dolphinfish are ray-finned fish, and are not related to dolphins, which are mammals. Red hypergiant WOH G64 is the 2nd largest known star in the universe at 1, times the size of the Sun. The most notable and easy-to-find star clusters in the constellation Dorado. Also see all star clusters. Notable and easy-to-find nebulae in the constellation Dorado. Also see all nebulae. It is approximately , light years distant and has an apparent magnitude of The star has a mass nine times that of the Sun.
HE was first discovered in by observers at the European Southern Observatory. Because it is moving at such a high velocity, the star is no longer gravitationally bound to the Milky Way and will eventually leave the galaxy and move into intergalactic space. The picture field is crossed by an impressive Milky Way, our own galaxy seen perfectly edge-on.
The most prominent objects on the Milky Way are: Sirius, the brightest star in the sky, visible at the top and the Carina nebula, seen as a bright patch besides the telescope. From the right edge of the picture to the left, the following objects are aligned: the Small Magellanic Cloud with the globular cluster 47 Tucanae on its right , the Large Magellanic Cloud and Canopus, the second brightest star in the sky.
Image: G. The galaxy has a radius of about 14, light years and is about , light years distant. It has a visual magnitude of 0. Its irregular appearance is believed to be a result of tidal interactions with the Milky Way and the Small Magellanic Cloud, a dwarf galaxy located in the constellation Tucana.
The infrared image, a mosaic of , individual tiles, offers astronomers a unique chance to study the lifecycle of stars and dust in a single galaxy. Nearly one million objects are revealed for the first time in this Spitzer view, which represents about a 1,fold improvement in sensitivity over previous space-based missions.
Most of the new objects are dusty stars of various ages populating the Large Magellanic Cloud; the rest are thought to be background galaxies. The Large Magellanic Cloud contains about open clusters, planetary nebulae, and 60 globular star clusters, and is home to innumerable supergiant and giant stars.
It is rich in gas and dust, and currently undergoing intense star forming activity. Amerigo Vespucci mentioned it in a letter in , about his third voyage. It was, however, Ferdinand Magellan whose writings introduced the Large Magellanic Cloud to Europeans, and the galaxy has subsequently been named after him. It is an exceptionally luminous non-stellar object; if it were as close as the Orion Nebula Messier 42 in Orion constellation , NGC would appear so bright that it would cast shadows.
The nebula has an absolute magnitude of Located inside the Large Magellanic Cloud LMC — one of our closest galaxies — in what some describe as a frightening sight, the Tarantula nebula is worth looking at in detail. Also known as 30 Doradus or NGC , the nebula owes its name to the arrangement of its bright patches that somewhat resemble the legs of a tarantula.
Taking the name of one of the biggest spiders on Earth is very fitting in view of the gigantic proportions of this celestial nebula — it measures nearly 1, light years across! Its proximity, the favourable inclination of the LMC, and the absence of intervening dust make this nebula one of the best laboratories to better understand the formation of massive stars.
This spectacular nebula is energised by an exceptionally high concentration of massive stars, often referred to as super star clusters.
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