|Is this what our own Milky Way Galaxy looks like from far away?
Similar in size and grand design to our
(although without the central bar), spiral galaxy
lies about 100 million
away toward the constellation of the Lion
above in exquisite detail by the
Hubble Space Telescope's
Advanced Camera for Surveys,
the big, beautiful face-on spiral is not only photogenic, but has proven
sharp enough to study individual stars known as
These pulsating stars have been used to accurately determine NGC 3370's distance.
NGC 3370 was chosen for this study because in 1994 the
spiral galaxy was also home to a well studied stellar explosion -- a
Type Ia supernova.
Combining the known distance to this
standard candle supernova,
based on the Cepheid measurements, with observations of
supernovas at even greater distances,
has helped to reveal the size and
of the entire Universe itself.