A schematic view of a mass-losing AGB star. The numbers are only indications on the orders of magnitude. ISM stands for interstellar medium, ISRF for interstellar radiation field, and HAC for hydrogenated amorphous carbon. For comparison, the solar radius is 7 10¹⁰ cm, the astronomical unit 1.5 10¹³ cm, and the parsec 3 10¹⁸cm

From

Le Bertre T., 1997, ``Cool Stars Winds and Mass Loss: Observations", Lecture Notes in Physics, Springer, Vol. 497, p. 133