Question

Problem A.3 :
The stellar parallax of the star Arcturus in the constellation Boötes was measures with 0.0900
.
(a) Calculate the distance (in parsec) between Arcturus and the Earth.
(b) How long does it take to send a light message from Earth to Arcturus?

Answer 1

(a) Calculate the distance (in parsec) between Arcturus and the Earth.

The relationship between a star's distance and its parallax angle:

$$d=\frac {1} {p} (1)$$

Using (1) we get:

d=11.11 parsecs

(b) How long does it take to send a light message from Earth to Arcturus?

1 light-year=0.3 parsecs

11.11 parsecs=37 light-year

Answer:

11.11 parsecs

37 light-year