The Cosmic Distance Ladder — Quiz Answers

An observed galaxy has a redshift of 0.006 What is the best estimate of its distance?

What trend is observed in the data?

Why is the technique of measuring geometric parallax only effective for measuring distances that are less than a few hundred parsecs?

Astronomers use the period-luminosity relationship of Cepheid variables and the distance modulus formula, m−M=5log_10⁡(d)−5 , to determine the distances to far-away stars and galaxies. In the formula, m represents a star's apparent magnitude, M represents its absolute magnitude, and d represents the distance in parsecs. A Cepheid variable has an apparent magnitude m=8.0 and is located 100 parsecs away. What is the star's absolute magnitude? Enter the correct value in the box.

Astronomers use the period-luminosity relationship of Cepheid variables and the distance modulus formula, m−M=5log_10⁡(d)−5 , to determine the distances to far-away stars and galaxies. In the formula, m represents a star's apparent magnitude, M represents its absolute magnitude, and d represents the distance in parsecs. A Cepheid variable has an apparent magnitude m=9.0 and an absolute magnitude M=−1.0 What is the distance to the star?

Astronomers use the period-luminosity relationship of Cepheid variables and the distance modulus formula, m−M=5log_10⁡(d)−5 , to determine the distances to far-away stars and galaxies. In the formula, m represents a star's apparent magnitude, M represents its absolute magnitude, and d represents the distance in parsecs. A Cepheid variable has an apparent magnitude m=12.0 and is located 1,000 parsecs from Earth. What is its absolute magnitude?

Astronomers use parallax to measure distances to nearby stars using the formula d=(1)/(p) where d is the distance in parsecs and p is the parallax angle in arcseconds. If the parallax angle of a star is measured to be 0.05 arcseconds, what is its approximate distance?

Astronomers use parallax to measure distances to nearby stars using the formula d=(1)/(p) where d is the distance in parsecs and p is the parallax angle in arcseconds. Astronomers have been observing Star A and Star B. Star A has parallax angle of 0.10 arcseconds and Star B has a parallax angle of 0.25 arcseconds. Choose the correct answers from each drop-down menu to complete the statements.

Astronomers use parallax to measure distances to nearby stars using the formula d=(1)/(p) where d is the distance in parsecs and p is the parallax angle in arcseconds. If the parallax angle of a star is measured to be 0.1 arcseconds, what is its approximate distance?