An astronomer is observing a single star (and one which does not vary) which she knows is located about 30 light-years away. What was the most likely method she or her colleagues used to obtain that distance?
A) bouncing radar beams off the star
B) measuring the star's parallax
C) the period-luminosity relationship
D) Kepler's laws
E) Hubble's law

Question

Quizplus · Accepted Answer

The most likely method used to obtain the distance of a nearby star is by measuring its parallax. This involves observing the star from two different positions on Earth and measuring the apparent shift in its position relative to distant background stars. By knowing the distance between the two observing positions and measuring the angle of the parallax, the distance to the star can be calculated. This method works best for stars within a few hundred light-years of Earth, which includes the star mentioned in the question at a distance of 30 light-years.

An Astronomer Is Observing a Single Star (And One Which