These analogy answers are weird and not helpful.
OP, they look through telescopes and figure out how far away the stars are. They record it in a little diagram on a computer and eventually they get a good idea of what it looks like from the outside.
How can you see your house if you are inside of it?
Fun fact, in german there’s a saying that goes “to not see the forest because all of the trees” (which in english would be probably called “chess blindness”)
The English phrase is “missing the forest for the trees”
Not quite the same as chess blindness. Possibly the opposite. It basically means: being unable to see (or ignoring) the bigger picture because you’re too focused on minor individual details
You can’t really. At least not well enough to know for certain what it looks like from the street.
When we look at the sky, there is a line where there is way more stars than usual. This line goes all the way around the sky. This was called the milky way by the Greeks because it was like a road sparkled with milk drops. At some point, we deduced that we were in a group of stars arranged in a flat disk. Later, we realized that some weird space clouds (nebulae) were much further away than we thought and were actually other huge groups of stars like our own that we named galaxies, still after milk.
There are more details me course. Even along the line in the sky drawn by the milky way, there is one side where there is much more stars and dust than the other. We deduced that we were at the edge of the disk and the bright region was the center of our galaxy. Also, the amount of gas and dust that block certain types of light that teach us that our galaxy has arms.
That’s definitely the more PG-13 version of why the ancient Greeks called it the Milky Way lol. Alternate version from Wikipedia:
In Greek mythology, Zeus places his son born by a mortal woman, the infant Heracles, on Hera’s breast while she is asleep so the baby will drink her divine milk and thus become immortal. Hera wakes up while breastfeeding and then realizes she is nursing an unknown baby: she pushes the baby away, some of her milk spills, and it produces the band of light known as the Milky Way.
That’s a lot more PG-13 than I thought it was gonna be
Zeus pounds three cans of red bull and throws some Playboy flicks on his CRT, proceeds to spray galactic milk all over the universe
Great explanation, although I want to clarify that not all nebulae are galaxies. Nebulas are massive clouds of dust and gas that are found within galaxies. Other galaxies were previously thought to be nebulas in space outside of the Milky Way, called extragalactic nebulae. However, in the early 1900s it was proven that these were actually other galaxies and not nebulas, so the term is no longer used.
While there are nebulae in other galaxies, they are not easily visible to us, so the word nebula generally refers to those contained within the Milky Way.
Thanks! I added “some nebulae” to remove any misunderstanding
Which other galaxies are named after milk?
The word galaxy itself comes from the old Greek word for milk, so all galaxies are named after milk.
Cool. I was trying to figure out if there was a bovine with the root word Andromeda in it. Because there are dromedary animals. But even do that only got me as far as one Galaxy.
The same way as I can see most of my body even though I am inside it. Indeed, without a mirror I cannot check whether I got a drunk tramp stamp tattoo last night, but I can still see most of my body and get a decent idea on the shape it as, especially when comparing with other’s people bodies
Epic Spaceman made a video about it where he showed how it looks from an outside perspective and our point of view while explaining a bunch of other things.
In case you mean pictures like this; http://upload.wikimedia.org/wikipedia/commons/8/82/Milky_Way_Galaxy.jpg - they are not actually images of the Milky Way. As you’ve guessed, we can’t directly see it in its full spirally goodness from the inside. Instead, these pictures are either artist’s impressions based on scientific understanding, or pictures of different galaxies that are reckoned to be pretty similar to the Milky Way.
Though someday we may find a gigantic space mirror that allows us to see our own galaxy by zooming in on it enough.
The space mirror will be formed by some weird gravitational pattern that happens to send light back the way it came. Not like literal glass floating in space. Just some kind of optical distortion that acts as a mirror.
But we’ll be looking at our galaxy a long time ago.
The same way I see the hood of my car while sitting inside of it.
With our eyes, duh!?
Same way you can see your living room
Because we are inside it. You can literally just look up at the sky and there it is! It does help that we are more toward the edge of it, than towards the center.
As for like a zoomed out image of the entire thing? Math as well as microwave and other radiation maps taken with powerful telescopes and instruments either on Earth or in orbit. Most of the images of space you might see are doctored in a way to make them look better to human eyes; they were actually constructed from data that wasn’t necessarily visual. All the different colors of a rainbow nebula, for example, mean something, and the nebulas do not actually look that cool when seen with the naked eye.
If you’re standing inside a cloud you can still see the cloud.