Even “nearby” galaxies
beyond our own Milky Way galaxy are so far that it takes their
light millions of years to reach us. The images we take today
show how these galaxies looked millions of years ago.
The further a galaxy, the smaller it appears. You can use this
method to get a rough idea which galaxies are closer and which
are further. Although galaxies come in different shapes and sizes,
the spiral galaxies similar to our own Milky Way are thought to
be roughly the same size. So if a spiral galaxy looks half as big
as another, it is probably twice as far away.
1924. Edwin Hubble presents the first evidence that galaxies
lie far beyond the Milky Way. To date, billions of galaxies have
ABOVE: These galaxies - a group called
HCG 87 - are
a few of the billions of galaxies discovered beyond our Milky Way.