Question

1. the star betelgeuse has a parallax of 0.01 arc - seconds. is betelgeuse closer or farther than aldebaran?

Explanation:

Step1: Recall the relationship between distance and parallax

The distance $d$ (in parsecs) of a star is given by the formula $d=\frac{1}{p}$, where $p$ is the parallax angle in arc - seconds. For Betelgeuse, $p = 0.01$ arc - seconds. So, $d_{Betelgeuse}=\frac{1}{0.01}=100$ parsecs. We don't have the parallax value for Aldebaran in the problem, but generally, Aldebaran has a parallax of about 0.05 arc - seconds. Then $d_{Aldebaran}=\frac{1}{0.05} = 20$ parsecs.

Answer:

Betelgeuse is farther than Aldebaran.