The brightest star closest to Earth, excluding the Sun, is Sirius, also known as the Dog Star.

Here's why:

* Brightness: Sirius is the brightest star in our night sky, visible even in light-polluted areas.

* Proximity: While not the closest star overall (that honor goes to Proxima Centauri), Sirius is relatively close at a distance of approximately 8.6 light-years.

However, it's important to note that "brightest" can be a bit subjective. Some stars might be intrinsically brighter than Sirius, but they are much farther away, making them appear dimmer to us.