Stellar Parallax Distance Calculator

Estimate the distance to a star based on its parallax angle in arcseconds.

Formulas Used

The distance to a star is calculated using the parallax angle, with results provided in parsecs and light-years.

  1. Distance in Parsecs:

    \[ d = \frac{1}{\text{parallax}} \]

    Calculates the distance in parsecs, where parallax is in arcseconds.

  2. Distance in Light-Years:

    \[ d_{\text{ly}} = d \times 3.26156 \]

    Converts parsecs to light-years using the conversion factor 1 parsec ≈ 3.26156 light-years.

Example Calculations

Example 1: Nearby Star

Input: Parallax Angle = 0.2 arcseconds

Calculations:

  • Distance in Parsecs: \[ \frac{1}{0.2} = 5 \text{ parsecs} \]
  • Distance in Light-Years: \[ 5 \times 3.26156 \approx 16.31 \text{ light-years} \]

Result: Distance: 5 parsecs (16.31 light-years)

Example 2: Distant Star

Input: Parallax Angle = 0.01 arcseconds

Calculations:

  • Distance in Parsecs: \[ \frac{1}{0.01} = 100 \text{ parsecs} \]
  • Distance in Light-Years: \[ 100 \times 3.26156 \approx 326.16 \text{ light-years} \]

Result: Distance: 100 parsecs (326.16 light-years)

Example 3: Very Close Star

Input: Parallax Angle = 0.768 arcseconds

Calculations:

  • Distance in Parsecs: \[ \frac{1}{0.768} \approx 1.30 \text{ parsecs} \]
  • Distance in Light-Years: \[ 1.30 \times 3.26156 \approx 4.24 \text{ light-years} \]

Result: Distance: 1.30 parsecs (4.24 light-years, similar to Proxima Centauri)

How to Use the Calculator

Follow these steps to estimate the distance to a star:

  1. Enter Parallax Angle: Input the star’s parallax angle in arcseconds (e.g., 0.1 for a star at 10 parsecs).
  2. Calculate: Click “Calculate Distance” to see the result.
  3. Interpret Result: The result shows the distance in parsecs and light-years. If you see “Please fill in all fields,” ensure the parallax angle is provided and positive.
  4. Share or Embed: Use the share buttons to post results on social media, copy the result, or get an embed code for the calculator.

Note: This calculator assumes accurate parallax measurements. Actual measurements may include observational errors, and distances are approximate.