Understanding Parallax
Parallax is the apparent shift in a star's position when viewed from two different points in Earth's orbit around the Sun. The greater the parallax, the closer the star.
The Formula
The relationship between parallax (p) and distance (d) is:
* d = 1 / p
Where:
* d is the distance in parsecs
* p is the parallax in arcseconds
Calculation
1. Given parallax: p = 0.20 arcseconds
2. Plug into the formula: d = 1 / 0.20
3. Calculate: d = 5 parsecs
Converting to Light-Years
Since you might be more familiar with light-years, we can convert parsecs:
* 1 parsec ≈ 3.26 light-years
Therefore, the distance to the star is approximately:
* 5 parsecs * 3.26 light-years/parsec ≈ 16.3 light-years
