The five brightest stars in Earth’s night sky are, in order of decreasing brightness, Sirius, Canopus, Alpha Centauri, Arcturus, and Vega. Of these, Canopus only ever barely rises above the horizon from our location in Lynchburg, Virginia, and Alpha Centauri is visible only from much farther south.
There are really only two things that can make an object appear bright. Either it is inherently bright (luminous), or it is close to us, or both. A candle held a few inches from your face can appear brighter than a powerful beacon several miles away.
The stars we see at night are quite atypical in that they are more luminous than most stars. Even our sun Sol, which is often but inaccurately described as “average”, is unusually large and luminous if we include all the smaller and dimmer stars in our stellar inventory.
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Most stars are in fact small, cool, and dim. They do not emit a lot of visible light—they “glow” in infrared radiation which is best observed from space-based telescopes. They are known as red dwarves.
So how about those bright stars? Are they luminous, or just close to us? Sirius is both—more than 25 times more luminous than Sol and only 8.71 light years away. Practically a next-door neighbor! Canopus is much farther away—310 light years—but it is 10,000 times more luminous than our home star. Alpha Centauri is part of a triple star system that is the nearest to Earth. It is only about 50% more luminous than Sol, but it is only 4.37 light years away. Arcturus? 170 times Sol’s luminosity and 36.7 light years away. And Vega is 25 light years away and 40 times more luminous than Sol.
This website gives you a three-dimensional representation of bright stars. Fun to play with!
Are there stars which are closer to us but too dim to see? Yes, indeed.
The five NEAREST stars to Earth are, in increasing order of distance, Proxima Centauri (one of three stars in a system of which Alpha Centauri is the brightest), Barnard’s Star (six light years away, invisible to the naked eye), Luhman 16 (A binary brown dwarf system. Brown dwarfs occupy a middle ground between giant planets like Jupiter and small stars large enough to initiate nuclear fusion of ordinary hydrogen in their cores.), Wolf 359 (a red dwarf), and Lalande 21185 (another red dwarf). Only Alpha Centauri is luminous enough to see without the aid of a telescope.
Stars (the astronomical kind) are similar to stars (the Hollywood kind). They are more obvious and less typical of the vast majority of either stellar objects or of the human population.
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