Density of stars
Astronomical distance
Brightness of heavenly bodies
Orbital velocity of giant stars
Answer is Wrong!
Answer is Right!
The correct answer is: B. Astronomical distance.
A parsec is a unit of astronomical distance equivalent to 3.26 light-years, or 30.86 trillion kilometers (19.17 trillion miles). It is used to measure the distance to stars and other objects outside the solar system.
The other options are incorrect because:
- Density is a measure of how much mass is contained in a given volume. It is not measured in parsecs.
- Brightness is a measure of the amount of light emitted by an object. It is not measured in parsecs.
- Orbital velocity is a measure of how fast an object orbits another object. It is not measured in parsecs.