One of you wrote:
Are there any stars outside our own galaxy that we can see with just the eye?
The answer is no – unless you count seeing the combined light of many billions of stars. From the Northern Hemisphere, the only galaxy outside our Milky Way that’s easily visible to the eye is the great galaxy in the constellation Andromeda, also known as M31. More about the Andromeda galaxy at the bottom of this post.
From the Southern Hemisphere, it’s possible to see two dwarf galaxies, the Large and Small Magellanic Clouds.
So what are we seeing when we look up? The image at the top of this post shows a hazy band in the sky. This is the edgewise view into our own Milky Way galaxy. Our galaxy is about 100,000 light-years in a diameter, but it’s relatively flat, only about 10,000 light-years thick. So – if we’re looking in a dark sky – when we look toward the galactic disk, we see the starry band of the Milky Way.
And when we look up or down – away from the flat disk of the galaxy – we’re also seeing Milky Way stars. All of the stars we see with the eye alone belong to our Milky Way galaxy.
It is possible to see the Andromeda galaxy with the eye alone, from Earth’s Northern Hemisphere. This galaxy appears as a hazy patch in our night sky, about as wide in diameter as a full moon. And, indeed, this haze represents the light of the Andromeda galaxy’s billions of stars. But we still can’t see individual stars within this galaxy – not with the eye alone. Even with amateur telescopes, the patch of light that we see as the Andromeda galaxy looks, at best, like haze.
A few years ago, astronomers released a new sharpest-ever view of the Andromeda galaxy.
And you can see the galaxy for yourself. At mid-northern latitudes in late November, the Andromeda galaxy is visible from nightfall till about 4 a.m. Here are a couple of ways to find the galaxy:
Be sure to look for it in a dark sky, far from city lights. Good luck!
Bottom line: On a dark night, there are so many stars. Are any of the stars we see with the eye alone located beyond our home galaxy? The answer is no. All the stars we see with the eye alone belong to our Milky Way. But there is one distant galaxy you can see from Earth.