How Many Stars Can You See At Night?

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Greene, Nick. "How Many Stars Can You See At Night?" ThoughtCo, Mar. 2, 2017, thoughtco.com/how-many-stars-can-you-see-3071116. Greene, Nick. (2017, March 2). How Many Stars Can You See At Night? Retrieved from https://www.thoughtco.com/how-many-stars-can-you-see-3071116 Greene, Nick. "How Many Stars Can You See At Night?" ThoughtCo. https://www.thoughtco.com/how-many-stars-can-you-see-3071116 (accessed October 24, 2017).
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The closest star to the Sun, Proxima Centauri is marked with a red circle, close to the bright stars Alpha Centauri A and B. Courtesy Skatebiker/Wikimedia Commons.

How Many Stars Can You See at Night?

When you step outside at night, the numbers of stars you see depends on a number of factors. All things being equal, you can see around 3,000 stars with the naked eye from a dark-sky observing sky. Light pollution reduces the number of stars you can see. However, you can usually see at least a few bright stars and planets from a light-polluted city such as New York or Beijing.

The best place to do your stargazing from is a dark-sky sight, such as Canyonlands National Park or from onboard a ship in the middle of the ocean, for example. Most people do not have access to such areas, but you can get away from most city lights by going out into the countryside. Or, if you must view from in the city, pick an observing spot that is shaded from nearby lights. 

What's the Closest Star I Can See?

The closest star to our solar system is actually a system of three stars called the Alpha Centauri System, consisting of Alpha Centauri, Rigil Kentaurus, and Proxima Centauri, which is actually slightly closer than her sisters. This system is 4.3 light years from Earth.  

Are there Other Nearby Stars We Can Observe?

Other nearby stars to Earth and the Sun are:

  • Barnard's Star — 6 light-years
  • Wolf 359 — 7.7 light-years
  • Luyten 726-8A and 8B — 8.4 light-years
  • Sirius A and B — 8.6 light-years
  • Ross 154 — 9.4 light-years

All the other stars we see in the sky are greater than 10 light-years away. A light-year is the distance light travels in a year, at a speed of 299, 792, 458 meters per second. 

What is the Most Distant Star Seen with the Naked Eye?

The most distant star you can see with your naked eye depends on your viewing conditions, plus the type of star it might be.

It could be that a supernova in the Andromeda Galaxy might be bright enough for you to see as it flares up. But, that's a rare occurrence. Among the "regular" stars out there, astronomers have suggested that the star AH Scorpii (in the constellation Scorpius), and the star V762 (a variable in Cassiopeia) could be the most distant stars in our galaxy that you can observe without using binoculars or a telescope. 

Why Are the Stars I See Different Colors and Brightnesses?

As you stargaze, you might notice that some stars appear white, while others are bluish, or orange or red. The star's surface temperature affects its color — a blue-white star is hotter than a yellow or orange star, for example. Red stars are usually fairly cool (as stars go).

Also, the materials that make up a star (that is, it's composition) can make it look red or blue or white or orange. Stars are primarily hydrogen, but they can have other elements in their atmospheres and interiors. For example, some stars that have a lot of the element carbon in their atmospheres look redder than other stars. 

A star's brightness is often referred to as its "magnitude".  A star can look bright or dim depending on its distance.  A very hot, bright star that lies very far away from us appears dim to us, even though if we were closer, it would be brighter.

A cooler, intrinsically dim star might look very bright to us if it lay nearby. For stargazing, you are interested in something called "visual (or apparent) magnitude", which is the brightness it will appear to the eye. Sirius, for example, is -1.46, which means that it's quite bright. It is, in fact, the brightest star in our night sky. The Sun is magnitude -26.74. The dimmest magnitude you can detect with the naked eye is around magnitude 6. 

 

Edited and expanded by Carolyn Collins Petersen.