* Galaxies are not well-defined objects: They don't have sharp edges like a planet or a star. They have diffuse outer regions where stars become increasingly sparse.
* Measuring size depends on what you're looking at:
* Optical diameter: This refers to the size we see with telescopes in visible light. NGC 1132's optical diameter is about 1.5 arcminutes.
* Physical diameter: This is the actual size of the galaxy in light-years. This is harder to measure accurately and depends on how you define the galaxy's "edge".
* Galaxies evolve and change: Their size can change over time due to mergers, star formation, and other galactic processes.
Therefore, while we can measure the apparent size of NGC 1132 from Earth, getting a precise physical diameter is very challenging.
