CAIE A-Level Physics A2 13.2.1 That for a Point Outside a Uniform Sphere the Mass of the Sphere May Be Topic Practice

The nearest star to the Sun is Proxima Centauri.

This star has a mass of $2.5 \times 10^{29} \mathrm{~kg}$ and is a distance of $4.0 \times 10^{13} \mathrm{~km}$ from the Sun. The Sun has a mass of $2.0 \times 10^{30} \mathrm{~kg}$.

State why Proxima Centauri may be assumed to be a point mass when viewed from the Sun.