Convert Arcsecond (Second Angle) to Radian
Unit definitions
Arcsecond (Second Angle)
$\frac{1}{3\,600}$ of a degree is an arcsecond. It is used in places where extremely precise measurements are required. It is said that the US dime is $1$ arcsecond wide from $2.3$ miles away.
Radian
The radian is the unit of angle in the SI. A full circle is $2\pi$ radians, where $\pi$ is approximately $3.141\,592\,653\,589\,793$.
How to convert Arcsecond (Second Angle) to Radian
$$\text{Angle}_{\text{rad}} = \frac{\text{Angle}_{\text{′′}}}{648000} \cdot 3.141592653589793$$
Examples
Example 1
Convert $45.0\ \text{′′}$ to $\text{rad}$.
$$\text{Angle}_{\text{rad}} = \frac{45.0}{648000} \cdot 3.141592653589793$$
$$\text{Angle}_{\text{rad}} = 0.000218$$
$$\therefore \ 45.0\ \text{′′} = 0.000218 \ \text{rad}$$
Example 2
Convert $80.0\ \text{′′}$ to $\text{rad}$.
$$\text{Angle}_{\text{rad}} = \frac{80.0}{648000} \cdot 3.141592653589793$$
$$\text{Angle}_{\text{rad}} = 0.000388$$
$$\therefore \ 80.0\ \text{′′} = 0.000388 \ \text{rad}$$
Example 3
Convert $115.0\ \text{′′}$ to $\text{rad}$.
$$\text{Angle}_{\text{rad}} = \frac{115.0}{648000} \cdot 3.141592653589793$$
$$\text{Angle}_{\text{rad}} = 0.000558$$
$$\therefore \ 115.0\ \text{′′} = 0.000558 \ \text{rad}$$
Example 4
Convert $150.0\ \text{′′}$ to $\text{rad}$.
$$\text{Angle}_{\text{rad}} = \frac{150.0}{648000} \cdot 3.141592653589793$$
$$\text{Angle}_{\text{rad}} = 0.000727$$
$$\therefore \ 150.0\ \text{′′} = 0.000727 \ \text{rad}$$
Example 5
Convert $190.0\ \text{′′}$ to $\text{rad}$.
$$\text{Angle}_{\text{rad}} = \frac{190.0}{648000} \cdot 3.141592653589793$$
$$\text{Angle}_{\text{rad}} = 0.000921$$
$$\therefore \ 190.0\ \text{′′} = 0.000921 \ \text{rad}$$
Arcsecond (Second Angle) to Radian conversion table
Convert Arcsecond (Second Angle) to other Angle units
| Arcsecond (Second Angle) [′′] | Other unit |
|---|---|
| 1 | 0.000278 Degree [°] |
| 1 | 0.016667 Arcminute (Minute Angle) [′] |
| 1 | 0.000001 Revolution [rev] |
| 1 | 0.000485 Centiradian [centiradian] |
| 1 | 0.000309 Grade [grad] |