The Hubble Space Telescope has been used to take a 1.5 billion pixel image of Andromeda Galaxy. More than 100 million of its estimated trillion stars are visible in this image, provided you go deep enough. Most of Andromeda’s stars are simply too faint to be seen at this distance, even with a telescope as powerful as Hubble. However the image doesn’t take in the full width of this mighty galaxy. The part photographed is 40,000 light years across. The galaxy’s full diameter is estimated at 3-5 times this size. Because the galaxy is only 2.5 million light-years from Earth, it is a much bigger target in the sky than the myriad galaxies Hubble routinely photographs that are billions of light-years away. The Hubble photograph is assembled together into a mosaic image using 7,398 exposures taken over 411 individual pointings.
There are over 100 billion galaxies out there. Makes what you think or do in your day to day activities rather mundane.