Part A Interstellar extinction is sometimes measured in magnitudes per kiloparsec (1 kpc = 1000 pc). Light from a star 1700 pc away is observed to be diminished in intensity by a factor of 28 over and above the effect of the What is the average interstellar extinction, in mag/kpc, along the line of sight? inverse-square law. Express your answer using two significant figures. VO AEQ ? extinction = mag/kpc Submit Request Answer Provide Feedback