How big is پروکسیما قنطورس?

Wolf 359 is a small red dwarf, dwarfed by normal stars. It is the sixth closest star to Earth, after the Sun, Proxima Centauri, Alpha Centauri A & B and Barnard's Star. Still, its magnitude is a dim +13.5.

Gliese 229B is a brown dwarf star. It orbits a larger dwarf star, which is Gliese 229A. Gliese 229B would be classified as a planet, but it is much denser than Jupiter, making its mass too large to be considered a planet.

Jupiter is the largest planet in the solar system. However, it is not the largest known planet. That's TrES-4b. Jupiter is a gas giant, so it's just a ball of gas. You can't land anywhere on it. Also, Jupiter has 80 moons, including the four Gallilean moons.

TrES-4b is one of the largest planets discovered. No telescope can actually see TrES-4b, but there are ways to prove its existence indirectly. TrES-4b's gravity causes the star it orbits to wobble slightly. Also, whenever TrES-4b goes in front of the star, the shine of the star dims a little.

The Earth and the Moon here are not to scale. If the distance were a meter, Earth would be the size of a quarter, and the moon would be a pea.

Kapteyn's Star is only thirteen light-years away. Even so, its magnitude is +9, so you need binoculars to see it. Around 10,000 years ago, Kapteyn's Star was only seven light-years away!