Why is it difficult to determine the distance to different stars? There are a variety of problems.
Turn on the Earth animation. How does the position of the star appear to change over the year? Why does this happen?
Move the actual location of the star. How can we use the effect of parallax to determine which stars are closer or further from Earth?
Suppose a star is some distance [i]d[/i] away from Earth. What would we need to measure to find the value of [i]d[/i]? What other information would we need?
Why will the parallax method only help determine the distance to relatively near stars and not extremely long distances like the distance to another galaxy?
A star that has a parallax of 1 second (1/3600 of a degree) is at a distance of 1 parsec from Earth. How far away is a star that has a parallax of 2 seconds? Explain your answer or do the calculation.