Question

How stellar parallax is measured?

Answer 1

Earth's orbit is used as base i n measurements..It is 300 million kilometers .measurements are done after 6 months time.

Explanation:

See how the angle of parallaxis assured from diagram.
d=1/p
where d=distance to stars in parsecs.
p= parallax angle in arc seconds
picture credit joefshersherloperlon blog spot.com..