Why do most stars show no parallax angle?

Why do most stars show no parallax angle? a. There are not sufficient background stars to measure the shift. b. Most stars show a blue shift which blurs the parallax measurement. c. The atmosphere blurs the measurements. This creates inaccuracies. d. They are so far away that we ca not measure the apparent... show more Why do most stars show no parallax angle?

a. There are not sufficient background stars to measure the shift.
b. Most stars show a blue shift which blurs the parallax measurement.
c. The atmosphere blurs the measurements. This creates inaccuracies.
d. They are so far away that we ca not measure the apparent shift against the background stars.
e. The rotation of the earth distorts the angle measurement.
6 answers 6