|Why isn't spiral galaxy
density waves of gas, dust, and newly formed stars circle a
center and create a
nearly symmetric galaxy.
The differences between
spiral arms and the apparent displacement of its
nucleus are all likely caused by previous close interactions and the
tidal gravitational pulls
of nearby galaxy neighbors
M65 and NGC 3628. Spiral galaxy M66, pictured here, spans about 100,000 light years, lies about 35 million light years distant, and is the largest galaxy in a group known as the Leo Triplet. Like many spiral galaxies, the long and intricate dust lanes of M66 are seen intertwined with the bright stars and nebulas that light up the spiral arms.
S. Van Dyk
D. De Martin &