March 24, 2020

The Milky Way: Our Home Galaxy

Galaxies are huge collections of stars that are held together by gravity, which is the very same force that keeps you from flying off the face of the Earth.

Our Sun is a star, like the ones you see twinkling overhead at night. The Sun, all the planets, and everything else in the solar system is part of the Milky Way Galaxy, which looks something like the picture you see here. The Milky Way Galaxy is a big spinning spiral that contains billions of stars.

Generally speaking, astronomers know what the Milky Way looks like, but they don’t have an actual picture of it. Why? Because it would take a space ship millions of years to get far enough away from the galaxy to snap a photo! So the picture you see here is an artist’s idea of what our home galaxy looks like.

Today's Podcast

Podcast #5: The Amazing Milky Way

More Fun Facts about the Milky Way

Fun Fact: If you happen to be in a very dark place, far away from city lights, you might be able to see the Milky Way in the nighttime sky. It looks like a faint, milky band across the sky.

Fun Fact: The Milky Way, which is our home galaxy, contains billions of stars. All but a few thousand of those stars are too far away to see unless you’re looking through a telescope.

Fun Fact: Light travels at 186,000 miles per second. So it takes about 8 minutes for light to travel from the Sun to the Earth. But, the Milky Way is so big that it would take that same beam of light 100,000 years to go from one side of our galaxy to the other side.

Fun Fact: A black hole is an area of space where gravity is so strong that even light can’t escape it. There’s a huge black hole is at the center of our galaxy, but that’s not unusual because most galaxies have black holes at their centers.

Fun Fact: The Milky Way has too many stars to count! But astronomers think that there are somewhere between 100 billion and 400 billion stars in the Milky Way. That’s billion with a “b” which is a lot of stars.

Fun Fact: Even though the Milky Way is loaded with stars, most of our galaxy is actually empty space between those stars. In fact, stars are so far apart that they almost never bump into each other. For example, the nearest star to our Sun is 4 light years away. That means that if you aimed a beam of light at our nearest star, it would take 4 years for the light to get there. But a regular spaceship, slow-poking along at a mere 17,600 miles per hour, would take about 165,000 years to get there!

Just for fun, see what you learned on the

Just for fun,
see if you can answer these questions.
Does the Milky Way contain millions of stars or billions of stars?

It contains billions of stars. By the way, one billion is equal to one thousand millions. 

How long does it take light to travel 186,000 miles? Is it one second, one minute, or one hour?

Light travels about 186,000 miles in just one second! That’s fast!

How long does it take light to travel from one side of the Milky Way to the other? Is it 100 year, 1,000 years, or 100,000 years?

It takes a beam of light 100,000 years to go from one side of the Mikly Way to the other side.

Are the stars in the Milky Way bunched closely together, or are they far apart?

They’re far apart. In fact, the stars in our galaxy are so far apart that they almost never bump into each other.

Quotes About Space

“Space is for everybody. It’s not just for a few people in science or math, or for a select group of astronauts. That’s our new frontier out there, and it’s everybody’s business to know about space.”
Christa McAuliffe

“Space isn’t far away at all. It’s only an hour’s drive away, if your car could go straight upwards.”
Fred Hoyle

“Astronomy compels the soul to look upward.”
Plato

“Forty years as an astronomer has not lessened my enthusiasm for lying outside after dark, looking up at the skys.”
Frank Drake

“The sky is the ultimate art gallery just above us.”
Ralph Waldo Emerson 

A Fun Fact: A black hole is an area of space where gravity is so strong that even light can’t escape it. There’s a huge black hole is at the center of our galaxy, but that’s not unusual because most galaxies have black holes at their centers. 

Well, you’ve amost reached the end of today’s Homeschool Express. But before you go, here’s something for you: a riddle.

Today's End-of-the-Line Riddle:
Where do astronauts keep their lunch?

In a launch box!

If you like the Homeschool Express, you should take a look at The Mystery Ryders, a series of chapter books about a homeschooling family that lives on a train, at least some of the time.