Store Magellanske Sky
Den Store Magellanske Sky (engelsk: Large Magellan Cloud eller LMC) er en aflang-oval dværggalakse i stjernebilledet Dorado (Guldfisken). Afstanden fra Solen til den Store Magellanske Skys midte er ca. 50.000 parsec, dvs. ca. 160.000 lysår.
Skyen kredser (vistnok) om vor egen galakse Mælkevejen og vil muligvis langsomt blive opslugt af denne. Vistnok og muligvis, fordi banens præcise form ikke er afklaret. Nogle observationer tyder på, at den har sit første møde med Mælkevejen, at dens bane er hyperbolsk og at LMC vil fortsætte sin rejse gennem universet bort fra Mælkevejen[1].
Stjernerne i den Store Magellanske Sky har en lav metallicitet i forhold til 3. generationsstjerner som Solen, nemlig Z = 0,006.
LMC ses tydeligt med det blotte øje på den sydlige himmelhalvkugle. Navnet har den fået, fordi den i udseende (om natten) minder meget om en ganske lille, almindelig sky, som de ses på daghimmelen.
Den Store Magellanske Skys J2000 position er Rektascension (RA) 5h 23m 36.00s deklination (DE) -69° 45' 00.0. Dens udstrækning er 550.0' x 170.0' og dens samlede tilsyneladende visuelle lysstyrke (mV) er 0,40, mens dens overfladeklarhed er mV 14,1.
Den Store Magellanske Sky er kendt for, at den klareste supernova siden 1604, nemlig SN1987A, i 1987 blussede op i denne galakse.
I en vinkelafstand af ca. 22° fra Den Store Magellanske Sky findes Den Lille Magellanske Sky.
Referencer
- ^ "Brief Encounter" (PDF). Astrophys. J. 668: 949. 2007.
Eksterne henvisninger
Koordinater: 
05h 23m 34.5s, −69° 45′ 22″
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Image of the planet Jupiter and one of its moons
This image shows the Large Magellanic Cloud galaxy in infrared light as seen by the Herschel Space Observatory, a European Space Agency-led mission with important NASA contributions, and NASA's Spitzer Space Telescope. In the instruments' combined data, this nearby dwarf galaxy looks like a fiery, circular explosion. Rather than fire, however, those ribbons are actually giant ripples of dust spanning tens or hundreds of light-years. Significant fields of star formation are noticeable in the center, just left of center and at right. The brightest center-left region is called 30 Doradus, or the Tarantula Nebula, for its appearance in visible light. The colors in this image indicate temperatures in the dust that permeates the Cloud. Colder regions show where star formation is at its earliest stages or is shut off, while warm expanses point to new stars heating surrounding dust. The coolest areas and objects appear in red, corresponding to infrared light taken up by Herschel's Spectral and Photometric Imaging Receiver at 250 microns, or millionths of a meter. Herschel's Photodetector Array Camera and Spectrometer fills out the mid-temperature bands, shown here in green, at 100 and 160 microns. The warmest spots appear in blue, courtesy of 24- and 70-micron data from Spitzer.
Forfatter/Opretter: ESO/S. Brunier, Licens: CC BY 4.0
Seen from the southern skies, the Large and Small Magellanic Clouds (the LMC and SMC, respectively) are bright patches in the sky. These two irregular dwarf galaxies, together with our Milky Way Galaxy, belong to the so-called Local Group of galaxies. Astronomers once thought that the two Magellanic Clouds orbited the Milky Way, but recent research suggests this is not the case, and that they are in fact on their first pass by the Milky Way. The LMC, lying at a distance of 160 000 light-years, and its neighbour the SMC, some 200 000 light-years away, are among the largest distant objects we can observe with the unaided eye. Both galaxies have notable bar features across their central discs, although the very strong tidal forces exerted by the Milky Way have distorted the galaxies considerably. The mutual gravitational pull of the three interacting galaxies has drawn out long streams of neutral hydrogen that interlink the three galaxies.
Image of the Large Magellanic Cloud and Supernova 1987A taken by the Kuiper Airborne Observatory (NASA 714) during its New Zealand deployment in 1987.