Question

In relation to the size of a galaxy, how do you convert arcminute into distance?

Answer 1

1 arc sec distance is 1 parsec = 206265 AU, nearly.
k arc minute distance = k X 60 parsec.

Explanation:

1 arc sec in radian measure is 4.48136811 E-06 radian. If the arc that subtends this angle at the observer is 1 AU long, the distance of the deep-sky object is defined as 1 parsec.

Use the circle formula R `theta` = arc length to understand this explanation. Here, `theta` is in radian measure.
So, 1 parsec = `1 / (4.48136811 E-06)` AU.