Question

how large is our solar system?

Explanation:

Step1: Define boundary

The solar - system's size can be defined by the distance to the outermost known objects. The most widely - accepted boundary is the heliopause, where the solar wind's influence is stopped by the interstellar medium.

Step2: State distance

The heliopause is about 120 astronomical units (AU) from the Sun. One AU is the average distance between the Earth and the Sun, approximately 149.6 million kilometers. So, in kilometers, the diameter of the solar system (assuming a roughly spherical shape with the Sun at the center) is about $d = 2\times120\times149.6$ million kilometers $\approx3.6\times10^{10}$ kilometers.

Answer:

The diameter of the solar system is about $3.6\times10^{10}$ kilometers (using the heliopause as the boundary, which is about 120 AU from the Sun and 1 AU $\approx149.6$ million kilometers).