SNR stands for "Signal-to-Noise Ratio" and is a measure used to assess the quality of a detected star in comparison to the background noise present in your image. "Signal" refers to the light intensity or the measured flux of a star, while "noise" accounts for any unwanted factors such as instrumental errors, atmospheric disturbances, or other sources of interference.


A higher SNR indicates a stronger, more easily discernible star, allowing for more reliable and accurate measurements of the stars's brightness.