[♪ INTRO]
[Sam] So this one’s Ursa Major, and the smaller one over here, that’s Ursa Minor.
[Jessi] Wow, those are really beautiful.
Hey there! Sam the Bat is showing me some constellations using his telescope.
Constellations are groups of stars that look like shapes or pictures in the night sky.
Here's a constellation you might have heard of before.
It's called "the Big Dipper" and it gets its name
because when you draw lines between each of its stars, it looks like a big soup ladle!
[Sam] Kind of like playing connect the dots!
[Jessi] Yes, exactly. The stars in constellations are actually really far apart from each other,
but from here on Earth, they look much closer together.
So when people look up, they make these pictures and share them with each other,
and sometimes they even tell stories about the things they see.
They might see a bear, or a spoon, or a….goat fish thing.
[Sam] I want to get a good look at this season’s constellations before we move away from them.
[Jessi] Oh, that’s right! Depending on what season it is, spring, summer, autumn, or winter,
people on different parts of the Earth get to see different stars and constellations.
Which constellations are you looking for, Sam?
[Sam] Pegasus! That’s the flying horse constellation!
[Jessi] That’s a great one - I think I see it right up there.
We can also look for Casseiopeia, or “The Big W”, or even The Dragon’s Head.
And you at home can see those constellations, too, if you’re in the Northern Hemisphere.
If you’re in the Southern Hemisphere, you might get to see Aquarius,
which looks like a man pouring water!
[Sam] Hey Jessi, do you know why you can’t see all the constellations all the time?
[Jessi] That is a great question, Sam!
The Earth moves around our Sun in a big loop throughout the year.
As that happens, we get the chance to look at different parts of space.
It’s like when you’re driving around the block in a car or a bus.
As you look out the window, you get to see different buildings that seem to move past you.
Because you’re moving, you get a different view of the space around you,
even though the buildings out there are actually staying still.
Earth is like our bus, and all of the stars and constellations stay in the same place,
but we move and see different ones throughout the year.
[Sam] Yeah! And what part of space you see can changes depending on what time of year it is.
As the Earth moves around the sun, we have a different view of space,
so we can see different stars and constellations.
Like, I’ve been looking at the constellation Orion.
Orion is easy to see from November to February here in the Northern Hemisphere,
because we’re facing it at night time.
But by June, our planet has moved to a place where we’re facing Orion during the daytime,
and the Sun is too bright for us to see it then.
So at night, Orion is completely out of view, and we see other stars.
[Jessi] Constellations are so fascinating! And these star pictures aren’t just for fun.
Some stars and the constellations that help us recognize them are really important
for helping people find their way.
[Sam] That’s so cool! But how can a star help someone find their way?
[Jessi] Let me show you. This is Polaris, the brightest star in the constellation Ursa Minor.
Some people call Ursa Minor the Little Bear, or the Little Dipper.
[Sam] Oh, I know about Polaris! It has another name, too. Some people call it the North Star.
[Jessi] That’s right! When we look up into the sky, the North Star is always north of us.
That means that if you can find the North Star, you know how to go north!
[Sam] But what if you don’t need to go north? What if you need to go a different direction?
[Jessi] That’s a good question. Let’s say there’s a ship full of people
who need to get to an island that they know is south of where they are.
If they look up and find the North star,
they just need to sail in the opposite direction of that star.
Even if they have a map to tell them where to go,
they can always check Polaris to make sure they’re on track.
As people got better at navigating and finding their way with the stars,
they designed special tools that helped them to use Polaris to guide them,
even across the ocean.
[Sam] It’s amazing that a star can be so helpful, even though it’s super far away.
Oh, hey Jessi! Do you want to look and see if we can find a bat-shaped constellation?
[Jessi] We can certainly try!
Before we go, do you want to answer a question from one of our viewers?
[Sam] Sure, that sounds fun!
[Jessi] Ok! Today’s question comes from Gemma, age 8.
Gemma asks “Why do I get side-aches when I run?”
Well, side-aches, or side-stitches, are common for many people
when they run, swim, and exercise.
Side-stitches can hurt, like you’ve pulled a muscle in your side.
Doctors don’t actually know for certain what causes them yet, but scientists have some ideas.
There are a few body parts near where people feel side-stitches that could be causing the pain.
First, it could be your diaphragm.
The diaphragm is a special muscle under your lungs that helps with breathing.
When you run, you have to breathe more heavily, and your diaphragm has to work harder.
Side-aches could be caused by your diaphragm getting sore from working so hard.
Another idea is that the pain could come from the ligaments near your diaphragm.
Ligaments are special body parts inside that help hold your body parts together.
If the ligaments get jolted around and aren’t used to working hard to hold things together
while you run, they could get sore, too.
While we don’t yet know exactly what causes side-stitches,
doctors know some ways to help avoid them.
[Sam] You could wait a little while after you eat before you go run and play,
instead of getting up right after.
And make sure to stretch your sides and your middle before doing a lot of running around.
And keep growing stronger!
As you practice things like running more, your muscles and ligaments can grow stronger,
and won’t get tired and sore as easily.
Thank you for your awesome question, Gemma, and good luck with your running!
[Sam] Meanwhile, I think we’ll exercise our eyeballs looking at space.
[Jessi] Looking at how the night sky changes through the seasons
and over big chunks of time can be really fun!
The more I learn about constellations and navigating by stars, the more I want to know.
What constellations have you seen in the night sky?
Have they seemed to move with the seasons?
What do you think it would be like to find your way using the stars?
Be sure to hit the subscribe button to keep exploring with me,
Sam the Bat, Squeaks, and all of our other friends!
And we’ll see you next time, here at the Fort.
[Sam] Bye!
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