NGC 4414: A Flocculent Spiral Galaxy
How much mass do flocculent spirals hide?
The featured image of
flocculent spiral galaxy NGC 4414 was taken with the
Hubble Space Telescope
to help answer this question.
Flocculent spirals -- galaxies without well-defined spiral arms --
are a quite common form of galaxy, and
NGC 4414
is one of the closest.
Stars and gas near the visible edge of
spiral galaxies
orbit the center so fast that the gravity from a large amount of unseen
dark matter must be present to hold them together.
Understanding the matter and
dark matter
distribution of NGC 4414
helps humanity calibrate the rest of the galaxy and, by deduction,
flocculent spirals in general.
Further, calibrating the
distance to
NGC 4414 helps
humanity calibrate the cosmological distance
scale of the entire
visible universe.