The largest NASA Hubble Space Telescope image ever assembled is a view of a portion of the Andromeda galaxy. It is the sharpest large composite image ever taken of our galactic next-door neighbor.
The Hubble Space Telescope is powerful enough to resolve individual stars in a 61,000-light-year-long stretch of the galaxy’s pancake-shaped disk. It’s like photographing a beach and resolving individual grains of sand.
The small image reproduced here is nothing compared to the real high-resolution one – which is now my desktop image. On that there are over 100 million stars with some of them in thousands of star clusters seen embedded in the disk.
Andromeda is only 2.5 million light-years from Earth, so it is a much bigger target in the sky than the myriad galaxies Hubble routinely photographs that are billions of light-years away.
Can we even conceive of that magnitude?
The Hubble survey is assembled together into a mosaic image using 7,398 exposures taken over 411 individual pointings.