CONTAMINATION BY SUPERNOVAE IN GLOBULAR CLUSTERS

Credit: ALMA (ESO/NAOJ/NRAO)/Alexandra Angelich (NRAO/AUI/NSF)

Only a small amount of the supernovae products remains trapped within globular clusters and this "catch" only occurs in the most massive cases (mass cluster ≥ 10^6 solar masses).
In smaller clusters instead there is no contamination by supernovae (supernova explosions produce heavier elements such as iron, gold, etc.). A group of astrophysicists has shown that the shock wave and the metals produced by supernovae disperse outside the cluster. This inhibits the gas contamination used by the first stellar generation (a new stellar generation can arise from the "recycled gas" expelled by supernovae). Only the material ejected by the supernova at the center of a massive cluster remain trapped (the ejected material moves in a high-density medium and remains locked) and it is available to a stellar population of second generation.

To know more
http://arxiv.org/abs/1511.02918
http://iopscience.iop.org/article/10.1088/2041-8205/814/1/L8/pdf

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Credit: ESO/B. Tafreshi Brilliant blue stars litter the southern sky and the galactic bulge of our home galaxy, the Milky Way, hangs serenely above the horizon in this spectacular shot of ESO’s Paranal Observatory. This image was taken atop Cerro Paranal in Chile, home to ESO’s Very Large Telescope (VLT). In the foreground, the open dome of one of the four 1.8-metre Auxiliary Telescopes can be seen. The four Auxiliary Telescopes can be utilised together, to form the Very Large Telescope Interferometer (VLTI). The plane of the Milky Way is dotted with bright regions of hot gas. The very bright star towards the upper left corner of the frame is Antares — the brightest star in Scorpius and the fifteenth brightest star in the night sky. Text Credit: ESO Resources Antares overlooking an Auxiliary Telescope Next Post Small Asteroid or Comet 'Visits' from Beyond the Solar System

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