74 ASTRONOMY • OCTOBER 2019
BREAKTHROUGH
WORTHY OF A KING’S RANSOM
Many of the Milky Way’s stars — and most of the clouds of gas and dust that serve
as raw material for future stellar generations — reside in a disk that is barely
1,000 light-years thick. This crowded province cuts through the southern part of
the constellation Cepheus the King, where the pictured clouds glow brightly in the
infrared. Massive newborn stars illuminate the bright spot at the tip of the nebula on
the image’s left-hand side. To the right, another nebula seems to cradle the star
cluster Cepheus B just above it. This young stellar group lies about 2,400 light-years
from Earth. Scientists captured this four-color mosaic with NASA’s infrared-sensitive
Spitzer Space Telescope. NASA/JPL-CALTECH