When was the spiral galaxy discovered?

Answer 1

It wasn't until telescopes that people realized that the band of light reaching across the sky, called the Milky Way since ancient times, was actually made of an immense number of stars. Astronomers still did not really understand what they were seeing until the 20th century, however.

Until the 1920s, astronomers thought that what we now know to be our Milky Way Galaxy to be the entire universe, and that our whole universe was a few thousand light years across. Other "spiral nebulae" had been observed, but they were thought to be new star systems forming nearby. After Hubble (the astronomer, not the telescope named for him) observed Cepheid variable stars in the Great Nebula in Andromeda, he realized that the Andromeda "Nebula" was immensley distant, and ennormous in size, and, by extension, the other "spiral nebulae" were also huge and incomprehensibly distant. He called them "island universes", and realized that we were also in one, and that the 'Milky Way' band of stars across the sky was our galaxy's disk, seen from inside. So, even though people have been calling the band of light across the sky the Milky Way for thousands of years, it wasn't until the 1920's that we understood what it was--our galaxy!

We can see only a small part of our galaxy in visible light. Since the 1960s, radio astronomers have mapped out the structure of the entire galaxy, and shown it to be a large spiral galaxy of about 100 billion stars; we are in one of the spiral arms about 8 kiloparsecs (25,000 light years) from the center of our galaxy, more or less halfway from the center to the edge.

I think Gallileo came across the milky way in the 1600's. The cloudy band we now call the Milky Way has been known since ancient times (it's referenced in various cultural mythologies, for example). However, it was only in the past few centuries that it was properly identified as a galaxy, specifically our own.

== == The Milky Way's true age hasn't been discovered. The only knowledge we have is of a meteorite which dates 4.7 billion years ago. And yes, Galileo discovered the odd colors of the Milky Way in the 1600's. If we could escape our galaxy, scientists believe it would look like M-31(The Great Galaxy of Andromeda)
I would hesitate to talk about a "discovery" of something that is in plain sight - that people have been seeing for ... well, for as long as there have been people. Like the Sun, or the Moon, or trees, or animals - or the Milky Way.

Answer 2

When man first saw the Milky Way.

Come on now...that's probably not what the questioner meant.

In 1925, Edwin Hubble discover cepheid variable(s) in what we now call the Andromeda Galaxy. From those he could tell that the group of stars was too far away to be part of the Milky Way. It was the first proof that other galaxies exist.

Answer 3

The Milky Way has been known for as long as people have looked into the night sky. It may be hard for modern people, with the prevalence of artificial light reducing the sky to a paltry few dozen visible stars, to realize this, but it's actually pretty striking from dark locations and isn't at all hard to see.

It wasn't until about 1610 that it was proven that it was made of stars (though it had been speculated this was true much earlier, at least by 500 BC).

It wasn't until about 1925(!) that it was realized that the universe was larger than the Milky Way, and it became known that it was a galaxy instead of the galaxy.

Answer 4

Our Galaxy, the Milky Way is a spiral galaxy, so it would have been the first to be discovered.

It was seen by the earliest humans, but they neither knew it was a galaxy, let alone a spiral galaxy.

Around 384-322 BCE, Aristotle first had the idea that the "Milky Band" they saw was a large collection of stars.

In 1610, Galileo Galilei actually proved that the "Milky Band" was a large collection of stars, so the "Milky Band" was a galaxy.

In 1785 ,William Herschel deduced the shape of the Milky Way

In 1920, Edwin Hubble deduced the shape of our Galaxy as a spiral galaxy.

However, in 1899 a photograph was taken of the Andromeda Nebula, clearing showing the distinctive arms but was defined as a nebula and not a galaxy.

Answer 5

Roughly 1925. Research Edwin Hubble for detailed information.

Answer 6

No date can be put on a date of discovery or by whom

Answer 7

Since God created it...He created it about 1,000,000 Years ago I think? I dont know :P

Answer 8

Our own - the Milky Way. For a while, astronomers thought it was the entire Universe.

Answer 9

by telescopes.

Answer 10

Andromeda, its a naked eye object.