The Pinwheel Galaxy
Great photo of one of our cosmic neighbors, the Pinwheel Galaxy – our nearest face-on spiral galaxy, just 27 million light years away.
This photo was taken by John Chumack. He writes:
The Pinwheel Galaxy is approximately 70 percent larger than the Milky Way. The tiny, bright blue dots in the spiral arms are young, hot, blue star clusters. Little pink spots are star formation regions (H II) — massive stellar nurseries. It’s estimated that over 3,000 of these H II regions are scattered throughout the Pinwheel’s spiral arms. Note that several background galaxies can be seen in and around the spiral arms.
Bear in mind that if anyone happens to be sitting on an Earth-like planet revolving around their local Sun-like star on one of the arms of that galaxy, peering through a telescope at the Milky Way and wondering whether anyone here is peering through a telescope at them, the answer would be “No, not for another 27 million years.”
Note: The nearest galaxy to us is Andromeda, just 2.5 million light years away. So someone from there looking at us right now might just be able to catch sight of some of our pre-human ancestors.
Andromeda, incidentally, is about two and a half times the size of our Milky Way and has at least twice as many stars as our 200-400 billion.
If you want a closer look and don’t have a telescope, just hang on: Andromeda is heading our way and is expected to crash into the Milky Way around 3.75 billion years from now – around the same time as the Sun is going into its end-of-life phase, ballooning out and engulfing the Earth in fire.