Different generations NGC 1866
NGC 1866 is found at the very edges of the Large Magellanic Cloud, a small galaxy located near to the Milky Way. The cluster was discovered in 1826 by Scottish astronomer James Dunlop, who catalogued thousands of stars and deep-sky objects during his career.
However, NGC 1866 is no ordinary cluster. It is a surprisingly young globular cluster situated close enough to us that its stars can be studied individually — no mean feat given the mammoth distances involved in studying the cosmos! There is still debate over how globular clusters form, but observations such as this have revealed that most of their stars are old and have a low metallicity. In astronomy, ‘metals’ are any elements other than hydrogen and helium; since stars form heavier elements within their core as they carry out nuclear fusion throughout their lifetimes, a low metallicity indicates that a star is very old, as the material from which it formed was not enriched with many heavy elements. It’s possible that the stars within globular clusters are so old that they were actually some of the very first to form after the Big Bang.
In the case of NGC 1866, though, not all stars are the same. Different populations, or generations, of stars are thought to coexist within the cluster. Once the first generation of stars formed, the cluster may have encountered a giant gas cloud that sparked a new wave of star formation and gave rise to a second, younger, generation of stars — explaining why it seems surprisingly youthful.
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NGC 1866NGC 1866 ist die Bezeichnung für einen jungen, blauen Kugelsternhaufen in der Großen Magellanschen Wolke im Sternbild Dorado. NGC 1866 hat einen Durchmesser von 4′,5 und eine scheinbare Helligkeit von 9,7 mag. Das Objekt wurde am 3. August 1826 von James Dunlop entdeckt. .. weiterlesen