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TIGHTLY packed stars in globular clusters are transferring mass among
themselves. Measurements from the European Southern Observatory’s Very Large
Telescope in Chile show levels of oxygen, sodium, magnesium and aluminium
varying from star to star among slow-evolving dwarf stars like the Sun, even
though they are too small to produce these elements themselves. Luca Pasquini of
ESO says the heavy elements are the ashes of larger stars, which long ago blew
off their outer shells and shrank to become faint white dwarfs. Some of this
interstellar dust ended up in nearby stars, which in globular clusters are
separated by only light-days, compared with light-years in our own Sun’s
neighbourhood. The findings are to appear in a future issue of Astronomy and
Astrophysics.