Discover the cosmos! Each day a different image or photograph of
our fascinating universe is featured, along with a brief
explanation written by a professional astronomer. 2007 August 9
Explanation: Gathered at the center of this sharp skyview are
the stars of Messier 67, one of the oldest known open star
clusters. In fact, though open star clusters are usually much
younger, the stars of M67 are likely around 4 billion years old,
about the same age and with about the same elemental abundances
as the Sun. Open clusters are almost always younger because they
are dispersed over time as they encounter other stars,
interstellar clouds, and experience gravitational tides while
orbiting the center of our galaxy. Still, M67 contains over 500
stars or so and lies some 2,800 light-years away in the
constellation Cancer. At that estimated distance, M67 would be
about 12 light-years across. Authors & editors: Jerry Bonnell
(UMCP) NASA Official: Phillip Newman Specific rights apply. A
service of: ASD at NASA / GSFC & Mich