Why aren't all stars seen at night?

Answer 1

There are 20 billion stars in our galaxy, but most of them are too dim or too far away to be seen with the naked eye.

There are only 9,096 stars which have an apparent magnitude of 6.5 or less. At any given time, about half of them are above the horizon and half are below the horizon. On a clear moonless night when there is very little haze in the atmosphere and no streetlights nearby, your eyes could adjust to where you could see magnitude 6.5 stars. Under those ideal conditions, you could see about 4,000 or 5,000 stars.

There is always a little haze in the atmosphere, so being at higher altitude helps because you're looking up through a thinner layer of air. It also might help because generally speaking there are fewer street lights on mountain tops.

In an average city which has street lights, and when the moon is out, your eyes will adjust to the higher light levels and you probably won't even be able to see magnitude 4 stars, let alone 5 or 6. There are only 288 stars which have an apparent magnitude of 3.5 or less. At any given time, roughly half of them are below the horizon, and you won't be able to see the ones which are near the horizon either because trees and buildings are in the way, so you'd probably only see about 100 stars.

Answer 2

Limiting Visual Magnitude.
It's a term that describes the 'seeing' conditions in your immediate are.
If you're affected by even a light overcast or fairly moderate light pollution, you may have a limiting magnitude of about 3, meaning that you will be to see no stars dimmer than magnitude 3.
Even under the clearest of skies with good visiual acuity, most people can make out stars no dimmer than magnitude 6 or 6.5.
There is no way possible to see all of the stars... They're just too far away or too dim.

Answer 3

this can be caused by alot of reasons. if you life in a city then usually the lights block out the stars. Clouds are another obvious one but also. Some stars you can't see all the time because they travel closer and farther from earth. And you just can't see all the stars at one time anyways! stars are amazing! and God is amazing for creating them!

Answer 4

Some stars are small &/or far away, so their light is weak.
There is also a lot of gas or dark matter out in space.
If you are near a city or other source of light there's a glow.
The atmosphere scatters the light from both sources.
Besides, your eyes adjust to the background light level.

Answer 5

We can only see half the sky at any given moment; the other half is below the horizon (behind the Earth). So we can only see half of the stars in the entire sky -- at most; less because of light pollution, clouds, etc.

Answer 6

The patch of stars you see depends on where you are located on the planet. Some stars are too far north and some are too far south. I'm presuming that you are speaking of star gazing on clear nights.

Answer 7

Light Pollution.

Answer 8

Half the stars are in the sky at the same time the sun is - the sun is so bright that no other stars are visible.

Answer 9

Because it's only dark on one side of the planet at a time. The other side is in daylight, and daylight interferes with stellar observation. You don't have a very strong grasp of the obvious, do you?

Answer 10

They don't want to be seen. Not all stars want to be seen, just like Brittany Spears!