Stars don't "come out" at a specific time like the sun. They are always there, but we can only see them at night when the sun is below the horizon and not illuminating the sky.

Here's how to figure out when stars are visible on October 20th:

* Sunset: Check the sunset time for your location on October 20th. This can be found on a weather website or using a sunset calculator online.

* Twilight: After sunset, there's a period called twilight where the sky is still partially lit. This lasts about an hour.

* Darkness: Once twilight fades, the sky becomes dark enough to see stars.

Therefore, the stars will become visible sometime after sunset on October 20th, depending on your location and how dark the sky is.