If parallax can be measured with an accuracy of 0.01 arcsecond, and the mean density of stars in the solar neighbor is 0.1 pc^-3, how many stars can have their distance measured via parallax?
Added by Steven G.
Step 1
Parallax is the apparent shift in position of an object when viewed from two different points. In astronomy, it's used to measure the distance to nearby stars. The parallax angle is measured in arcseconds. The smaller the parallax, the farther away the star is. A Show more…
Show all steps
Close
Your feedback will help us improve your experience
Labs
Want to see this concept in action?
Explore this concept interactively to see how it behaves as you change inputs.
Key Concepts
Recommended Videos
Explain how parallax measurements can be used to determine distances to stars. Why can we not make accurate measurements of parallax beyond a certain distance?
A unit of length often used by astronomers to measure distances in "nearby" space is the parsec (pc), defined as the distance at which a star subtends a parallax angle of one arc second due to Earth's orbit around the Sun (see Equation $13-11$ and Example $13-4)$. The practical limit of such measurements is 0.01 arc second. ( $a$ ) How many light-years is $1 \mathrm{pc} ?(b)$ If the density of stars in the Sun's region of the Milky Way is $0.08 \mathrm{star} / \mathrm{pc}^{3},$ how many stars could, in principle, have their distances from us measured by the trigonometric parallax method?
If you measure the parallax angle for a star to be 0.5 arcseconds. The distance to this star is?
Morgan C.
Recommended Textbooks
University Physics with Modern Physics
Physics: Principles with Applications
Fundamentals of Physics
Transcript
Watch the video solution with this free unlock.
EMAIL
PASSWORD