Explanation:
M13
is one of the most prominent and best known
globular clusters.
Visible with binoculars in the constellation of Hercules, M13 is frequently one of the first objects found by
curious sky gazers seeking
celestials wondersbeyond
normal human vision.
M13 is a colossal home to over 100,000 stars, spans over 150
light years across,
lies over 20,000 light years distant,
and is over 12 billion years old.
At the 1974 dedication of
Arecibo Observatory, a
radio message
about Earth was sent in the direction of
M13.
The reason for the low abundance of unusual
blue straggler stars
in M13 remains unknown.
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