74 ASTRONOMY • JANUARY 2018
A tale of
three cities
The beauty of the Orion
Nebula (M42) belies the
firestorm of star birth
taking place within its
nebulous folds. But
this vast stellar nursery
shrouds another secret:
The young stars within
appear to have formed
in three separate bursts.
Astronomers uncovered
these populations by
analyzing the data in this
image taken through
the European Southern
Observatory’s VLT Survey
Telescope in Chile. The
researchers measured the
colors and brightnesses
of the thousands of stars
in the nebula’s core and
discovered what appears
to be three successive
generations born about
2.87 million, 1.88 million,
and 1.24 million years ago.
ESO/G. BECCARIBREAK
THROUGH