Learning about the Milky Way is something everyone should do. The Milky Way is one galaxy in the universe, and there are many more galaxies out there like it. And within the Milky Way is the solar system, and within the solar system is.. us! So, this really shows just how massive the Milky Way is. Let’s have a look at some interesting facts about it.
Milky Way Galaxy Facts
- If you look up at the night sky, everything that you see is within our galaxy the Milky way. The only thing that you can see outside of our galaxy without a telescope is the Andromeda galaxy.
- Our galaxy has an estimated radius of 52,850 light years.
- It is part of a group of galaxies which is called the “Local Group” – there are more than 30 galaxies in this group.
- The Milky Way is only the 2nd largest galaxy in our group of galaxies, after the Andromeda galaxy. In comparison to other galaxies, it is actually relatively small though – the IC 1001 is more than 50 times the size of the Milky Way.
- Although some people think that the Milky Way is an irregular galaxy, this isn’t the case. It is actually classified as a barred spiral galaxy due to it’s structure.
- We usually credit Galileo Galilei with discovering the Milky Way – of course, people before him had theorized it, but Galileo was the first person to use a telescope and see the thousands of stars up there in the night sky.
- Although many people think we are in the center of our galaxy, this actually isn’t true. We are more than 25,000 light years away from the center of our galaxy.
- We know of more than 500 different solar system in our galaxy already, with astronomers estimating that there could be billions more out there.
- However, don’t know exactly how many planets there are in the Milky Way, but some astronomers suggest that there are hundreds of billions of planets. It’s even said there a billions of planets like Earth, that have the potential to support life.
- We know that more than 95% of our galaxy is made up of dark matter.
- Our solar system orbits around the center of the Milky Way. It takes around 230 million years for it to make one full rotation.
The Structure of the Milky Way
The main components of the Milky Way are it’s central black hole, which is located at it’s Galactic center. This is bordered by the Galactic bulge, which is a lot of stars all grouped up together.
At the edge of this, you have the spiral arms of the Milky Way, which is split into four different segments – this makes up the “spiral” element of the Milky Way.
More Facts about the Milky Way
- In comparison to the rest of the Milky Way, our solar system is actually quite young. There are exoplanets that are 12-13 billion years old, in comparison to our solar system which is 4.5 billion years old.
- Whilst for many years astronomers thought the Milky Way was flat like a disc, it is actually quite warped – we’re still not sure what the definitive cause of this is.
- It’s estimated that anywhere between 10 and 15% of the Milky Way is made up of interstellar gas.
- We think that for the Milky Way to be the size that it is, it must have collided with another galaxy in it’s near 14 billion year lifespan.
- The Milky Way does not stay still – it’s actually continuously moving at a speed of more than 1,000,000km/h.
- The Milky Way actually has a halo made up of old stars.
- Although I’d love to be able to show you a true picture of the Milky Way, this isn’t possible as we can’t get far enough away to get one! All the images you see of the Milky Way are actually artists concepts.
- The Milky Way has many different smaller satellite galaxies that are bound to it by gravity. The largest of these is the Large Magellanic Cloud (or the LMC).
Common Questions about the Milky Way
What is in the center of the Milky Way?
Finding out what was the “center” has been a question for astronomers since well.. forever! Originally the Earth was the center of the universe, then the Sun.. now we know that we are merely a small part of a galaxy quite far away from the Universe’s center! So as I’ve mentioned, we are actually not anywhere near the center of our galaxy. But what is at the center of the Milky Way? Well we now know that at the center of our Milky Way is actually a supermassive black hole.
Why is it called the Milky Way?
A common question people have is just why it’s called the Milky Way. Well, it takes it’s name from the Greek Galaxios Kyklos, which literally means the “Milky Circle”. It is named this because of it’s milk-like textured appearance in the night sky.
Can I see the Milky Way?
When you’re trying to see the Milky Way, you need to look for it during the summer time, anytime between midnight and morning. However, it’s worth knowing that more than 30% of people will not be able to see the Milky Way from their location much of the time. This is due to light pollution. So if you live in a city, then you might have difficult even seeing the Milky Way.
What is the closest galaxy to the Milky Way?
Many people think that the Andromeda galaxy is the closest galaxy to the Milky Way. And whilst it’s true that it’s the closest big galaxy, it isn’t the closest galaxy overall. The closest galaxy to us is actually the Canis Major Dwarf Galaxy, which is around 25,000 light years from our solar system.
How many stars are in the Milky Way?
It would be impossible to tell just how many stars there are in the Milky Way, however experts say that there are likely more than a few hundred billion (remember, our Sun is nothing more than an average sized star!).
Our Milky Way is just one of the many galaxies out there, which is kind of crazy when you think about it. There’s the possibility that there are billions of other planets in different galaxies out there just like ours, however due to our distance from them, we’ll never know! I guess we’ll just have to be happy in our own Milky Way.