Question

Betelgeuse is approximately 650 light-years away. What is the approximate distance to Betelgeuse in parsecs and what is the parallax angle for Betelgeuse in arc-seconds?

Answer 1

To convert the distance to parsecs, we use the formula:

distance (in parsecs) = 1 / parallax angle (in arc-seconds)

Since we're given the distance in light-years and need the parallax angle in arc-seconds, we rearrange the formula to:

parallax angle (in arc-seconds) = 1 / distance (in parsecs)

First, let's convert the distance to parsecs:

distance (in parsecs) = 650 light-years / 3.26156 light-years per parsec
distance (in parsecs) ≈ 199.43 parsecs

Now let's calculate the parallax angle:

parallax angle (in arc-seconds) = 1 / 199.43 parsecs
parallax angle (in arc-seconds) ≈ 0.00502 arc-seconds

Therefore, the approximate distance to Betelgeuse in parsecs is 199.43 parsecs, and the parallax angle for Betelgeuse in arc-seconds is approximately 0.00502 arc-seconds.