What do you think, Iz?

It's called disco skating.

Oh...(laughs) "disco skating."

Don't worry, I have a secret weapon.

I figured out a lighting plan to make me a star.

Tah-dah!

What do you think?

(Miranda) We went stargazing and we couldn't see many stars outside.

(Tina) Light pollution is actually a really big environmental problem.

I'm lookin' up!

Oh!

Whoa!

(all) Star party!

(Izzie) Next on "SciGirls!"

(all laugh) (Izzy) Major funding for "SciGirls" is provided by the National Science Foundation-- supporting education and research across all fields of science and engineering.

The National Science Foundation-- where discoveries begin!

(woman) Additional funding is provided by ExxonMobil.

(girls) ♪ S-C-I-G-I-R-L-S (Izzie) ♪ We need you (girls) ♪ S-C-I-G-I-R-L-S (Izzie) ♪ Come on!

♪ When I need help, and I've got a question ♪ ♪ there's a place I go for inspiration ♪ ♪ Gotta get to the Web, check the girls' investigation ♪ ♪ What girls?

(Izzie) ♪ SciGirls!

Whoo!

(girls) ♪ S-C-I-G-I-R-L-S (Izzie) ♪ I need you!

(girls) ♪ S-C-I-G-I-R-L-S (Izzie) ♪ Come on!

♪ You've gotta log on, post, ♪ upload, pitch in!

Yeah!

♪ Wanna get inside a world that's fascinating?

♪ ♪ The time is right 'cause SciGirls are waiting, ♪ (girls) ♪ S-C-I-G-I-R-L-S (Izzie) ♪ We need you!

(girls) ♪ S-C-I-G-I-R-L-S (Izzie) ♪ SciGirls!!

Ei-yi-yi-yi-yi!

What do ya think, Iz?

It's called disco skating.

Oh...(laughs) "disco skating."

Wow, that's your talent for the talent show?

Yup, I can't really skate, can't really dance, but together, it's a golden combination.

And don't worry-- I have a secret weapon.

Secret weapon?

Meet me at school, and I'll show you.

Wow!

That is not going to be a secret for long!

I don't want it to be-- I want everyone's eyes on me.

And I figured out a lighting plan to make me a star.

Tah-dah!

What do ya think?

Can't take your eyes off my board, right?

Ah, actually, I can't really see it.

Um, hang on, let me take a picture, and I'll show you.

Here, start skating again.

(click!)

See?

Hey, where did my lights go?

I can barely see 'em!

I know, it's weird!

And devastating to my chances of winning.

If the judges just judge me on my dancing, I'm in trouble.

Yeah, I've seen your dancing!

(sighs) I'll tell you what.

I'll see if the SciGirls can help.

Whoo-hoo!

(Izzie laughs) Oh, let's see.

How do I make Jake shine?

Oh!

Hey, Jake wants to be a star.

Maybe this'll help.

So why don't we decorate the table with these glow-in-the-dark stars?

Because it's fun decorating, it's fun.

My name is Miranda, and I'm 12 years old, and I also have a nickname, which is Mary.

We're taking out the constellation charts so that our friends aren't lost trying to look at the sky.

Maybe we can get out the box of stars so they can see what different constellations there are.

My name's Avianna.

I'm 12 years old.

What I want to be when I grow up is a forensic scientist.

The thing that I love most about astronomy is that we get to go outside and locate stars and constellations that you've never seen before.

We're about to prepare ourselves for our star party that we're hosting.

(Miranda) Avi and I are both part of the Science Club for Girls.

Okay, so why don't we check on the telescopes.

We need to put on the viewfinder.

I'll put the eyepiece in.

We're very excited to show all our friends what we've been doing.

Yeah, we get to show them how to work the telescopes.

(Tina) This is a 9-inch refracting telescope.

(Avianna) We get to show them what we've been doing with the light pollution.

(Miranda) We could also show them Cygnus from the summer triangle, and other constellations.

(all laugh) (Miranda) Avianna and I went stargazing one day.

(both) Hercules.

Oh look, Orion.

It's easy to find.

Yeah, because Betelgeuse is very bright.

Oh look, it's the Big Dipper.

The Big Dipper is a bear?

Oh look, it's Bootes, it's your favorite one.

I know.

I Love it.

Here's Cassiopeia.

Your favorite, right?

Yeah.

(Miranda) Yeah, it looks like a lightning bolt, don't you think?

The myth is that Cassiopeia, so that she was so beautiful and that she was even more beautiful than the sea nymphs.

So then the sea nymphs complained to the god Poseidon, and to punish Cassiopeia, Poseidon put her in the sky.

I can't wait to look at some stars.

Set up the blanket so we can lay down.

Do you see anything?

What do you see?

Do you see that bright star?

We should try looking for the Big Dipper though.

Yeah, it's like, so easy to find.

Wait... can you find it?

At other places, I can just spot it out like that.

Can you find Bootes?

I can't really see it.

I can barely see it.

I think I can see that really bright star, Arcturus, yeah.

We really were looking forward to seeing all the stars, so we decided to call Tina for help.

So this is where Tina works.

Yeah.

Let's go in.

Tina is our mentor in Science Club for Girls.

Okay, so this is the last flight of stairs until we reach the roof.

Oh, there's Tina!

Hi Tina.

Hey Tina.

Hi,ladies.

(Miranda) Tina is studying at Harvard, and she getting her Ph.D. in astrophysics.

We were out stargazing, and we couldn't see any stars.

We're not that far away from the city right now, being at the Harvard Astronomy Department, so the idea of problems with lights, exactly what you guys just said, is a big issue.

I'm an astronomer, I want to look at the stars.

And you guys couldn't see that many stars at all, right?

Having too many lights around prevents you from being able to see the stars up there.

♪ ♪ Light pollution is actually a really big environmental problem, not just for astronomers.

There's a lot of inefficient lighting.

So the different types of bulbs we use, then sometimes we lose a lot of light if it's pointing upwards rather than downwards-- things like that.

That's just a waste of energy-- that's why we call it pollution, because it's actually affecting our environment even though it may not be something tangible like chemicals in the water or something like that.

When you're looking at the earth from space you'll see large pockets of light glowing from the cities.

You can map out entire city areas and streets from space based on that.

There are very few areas that are completely dark.

(Izzie) Whoa, look at that-- the east coast and the west coast-- they're so bright!

(Tina) One of the big projects this year for the International Year of Astronomy is called The Great World Wide Star Count.

"The Great World Wide Star Count?"

Oh cool!

I'm really excited you guys came to me with this problem you guys had.

So you basically count stars?

Yeah!

The Great World Wide Star Count, what it's trying to do, it's trying to measure light pollution by counting stars.

So when you were at the park you can only see the brightest stars.

So the more faint stars you can see is actually a measure of light pollution.

We're not scientists, so how can we do this?

We can figure out a method to quantify light pollution and do this variable by star count, and therefore we're scientists.

You don't have to have a degree or anything to be a scientist.

As far as I'm concerned you're doing experiments, you're investigating things-- that's the definition of a scientist.

The constellation that I've chosen to do for The Great World Wide Star Count is the constellation of Cygnus, which is inside the Summer Triangle.

The Summer Triangle is made up of these 3 stars here.

There's Vega, there's Altair, and there's Deneb.

One of those stars is actually the tip of the constellation Cygnus.

So when we talk about stars and how bright they are, we refer to a magnitude system.

When we are talking about light pollution, we're taking about a limiting magnitude, Everyone who's participating in The Great World Wide Star Count will be using the same system.

So if there's a lot of background light, then these fainter stars in this constellation are not going to be visible.

Let's say we can't see any stars except the brightest star, and one of the brightest stars in the sky is Vega, so that will be an example where light pollution is really bad.

So this would be a limiting magnitude of 1.

Then going onward, other features become visible.

(Izzie) Hmm... 1, 2, 3, 4, 5.

Got it!

Eventually there's this interesting s-shaped pattern that happens in the middle of the cross.

If you can actually see that, then we're in good shape.

Then you get to a point when you really can't-- just too many stars to figure out anything.

(Izzie) Let's see a SciGirls profile!

Hi.

My name is Miranda.

I'm 12 years old.

I enjoy playing piano.

(plays ragtime-- "The Entertainer" by Scott Joplin) Reading...

I love this book!

Drawing...

Here's my mom, and she's drawing.

Hi, how are you?

And a lot more.

"Ferocious kitty" is the lair of Oreo.

There he is!

So here's my room.

There's the wall things, my desk, my family.

Well, I had a great time.

Hasta pronto!

Bye.

(Izzie) Hasta pronto!

(Miranda) Avi and I have just stopped at my house...

So what do we need?

Telescopes.

...to pick up some supplies that we need to do the star count; the star charts, flashlight, red lights, maps.

If you zipper it, I got the jackets.

Why don't we locate ourselves.

How far away should we go to take our data?

Well, near the country where it's last light where we can really see the stars and do the star count.

Why don't we start 50 miles away?

Then we can have like, 10-mile intervals so that we can see the difference as we get closer into the city?

Well, we'll start in Westminster.

We'll end in like, Harvard Square.

Tina!

Tina!

Hi ladies.

We called Tina so we could go somewhere darker to see the stars.

Great to see you!

(SciGirls) You too!

You too!

(Tina) Are you excited?

(SciGirls) Yeah.

(Tina) All right, let's go.

♪ ♪ Thank you Tina, for helping us find what we are looking for.

Yeah, we're so excited.

We're on the road at last.

We're ready to go to our first site.

Whoo-hoo!

Headed out to the country!

(Miranda) I love Tina, she's my favorite mentor teacher.

(Tina) Have you seen all the stars before, or is this going to be something new for you?

Well, we both went camping... Yeah, in Gloucester.

...Gloucester, yeah, it's full of stars.

Did you know any of the constellations at that time?

Could you pick anything out?

The Big Dipper.

Yeah, Big Dipper and the Little Dipper.

(Tina) As we go out to the darker sites, there's going to be less buildings around, so there should be a lot less background light.

The thing with astronomy when you're looking for stars, it's all about contrast.

You're comparing a bright point in the sky, and it stands out more if the background around it is just darker, right?

So what happens is that there's all these buildings around, then it sends up all this light, and that's the background light.

So the difference between the bright point and the background light if there's a lot of buildings around is less.

So it's harder to see the faint things because of that.

So you want to decrease the background light as much as possible so that these things stand out more.

Ah-ha!

I got it!

Contrast!

Now I know how to fix Jake's skateboard!

Hmm, but this light bulb over my head might just cause a problem.

(Avianna) Tina, do you guys think we're there?

Are we there?

'Cause it's really dark.

(Tina) We're pretty close.

All right guys, we're here.

(Avianna) Wow!

There's so many stars!

(Miranda) There's so many stars.

It's like, unbelievable.

(Avianna) I know.

It's like I'm in a movie just watching it.

It's a lot different than the playground.

A lot.

It's like 20, 30 times better.

It's like we can see the brighter ones, and then if you look closely you can see the smaller ones.

I found Cassiopeia, it's pretty exciting.

Really?

Yeah.

(Tina) It's pretty fascinating, it's really overwhelming when you realize just how many stars there are out there.

Most of the stars we see in the night sky are actually all part of the Milky Way, so they're part of our own galaxy.

We're in the Milky Way, so we're seeing stars that are near us or farther away, but I guess the number of stars in the Milky Way itself is something on the order of 10 billion, maybe even a bit more that that.

so we're talking about a lot of stars-- it's far, far more than you can count.

Can you find it, the Summer Triangle?

Well, maybe we might need help from our constellation chart.

(Avianna) Good idea!

The star charts are like the map of the sky.

They just help you know which star is part of which constellation, so that you don't get lost.

But remember, it's dark outside, so...

So we need our... headlights.

(Miranda) We use red lights when we're stargazing because our eyes aren't as sensitive to the red lights as it is to the white lights.

(both) Bidle-bidle- bidle-dah!

(laughter) (Tina) When you have a map of the ground, you hold it on the ground, then you look in your directions-- not at the sky.

What do you do?

You can't look at it this way.

You have to point it upwards.

Oh, that makes sense.

That makes sense.

We're going up.

Okay.

Yup, I'm lookin' up.

Whoa!

Whoa!

Ah, I'm okay.

(Tina) So now you got 1, 2, 3.

Does that match?

(Avianna) Yup.

We looked for the Summer Triangle because it's very easy to find.

And there's one bright star right there.

So we can find the brightest star to the left.

(Avianna) Yeah, west.

(Miranda) I think I found it.

(Avianna) Yeah, I found it.

(Miranda) So that's Vega.

(Avianna) Look, there's all Altair.

And there's Deneb.

(Izzie) Yeah, I can see that!

Wow!

(Miranda) Once we find the Summer Triangle, we see Deneb, then we know that Deneb is part of Cygnus, so we can already start the star count.

Limiting magnitude 1.

"No stars in the cross are visible."

I say I can see more than that.

Yeah, me too.

Limiting magnitude 6.

"S-shaped curve of stars visible."

(Avianna) Then you could see this "s." See the long tail.

Yeah, you can see how faint the star is.

You can see a star.

(Tina) So you got this s-shape, so past limiting magnitude 6.

So then we must be on 7.

(SciGirls) "Too many stars to count."

(Izzie) Too many!

Does that look like the situation we've got here?

(SciGirls) Yeah.

(Tina) All right, so I think we really got to a dark location, right?

(SciGirls) Yeah.

It says the latitude, it's 42.54.

After we saw what the limiting magnitude was, we took out the Smartphone that had a GPS coordinates of the site.

So then we wrote them down on the notebook.

We're right there.

So next time, why don't we do it near North Leominster?

♪ ♪ I was freezing at the last place.

I was like an icicle.

All right, we're here ladies, come on out.

There's Deneb.

There's Vega.

(Avianna) It's a lot more clear than the "s" for the magnitude size.

(Miranda) Yeah, the "v" is a lot clearer than the "s" because we can only see 1 or 2 stars near the 3rd point, 3rd star down.

Yeah.

So I think...

I think it's a magnitude 5, right?

(Miranda) Yeah.

(Izzie) Yeah, 5.

Check!

(Tina) Ready to go to site number 3?

(both) Yeah.

(Tina) Perfect, let's go.

(Avianna) I wonder what we're going to get for our next site.

Okay, so we're about 30 miles away from the city.

We need help finding the Summer Triangle.

Yeah, we having a bit of...

Difficulties.

Me and Miranda had trouble seeing Cygnus at one of the locations, which was 30 miles away from the city.

The Summer Triangle was where above us?

It was right above us.

Exactly!

It was right above us, right?

But it's no longer there.

So what's happening as the night progresses?

The sky moves?

The earth slowly turns, right?

That's right-- the earth is rotating.

Oh wait, I knew that, but I didn't know how it applied to stars.

Now I know!

(Tina) From our vantage point we don't necessarily feel the earth moving, but what do we see moving?

(SciGirls) The sky.

(Tina) Right, the sky changes as the night goes on.

The constellations that were overhead earlier on the night are not going to be overhead anymore.

There going to be closer to the horizon.

So the fact that we're not seeing them probably just means we're not looking in the right spot, right?

So that's why we've gotta move.

(SciGirls) Okay.

I can only see the first top 2.

(Miranda) Yeah.

If we can only see 2, the whole "v" doesn't really count.

(Avianna) Yeah, it doesn't exist to us.

(Miranda) Yeah, so we'll have to go with limiting magnitude 4.

(Avianna) Yeah.

♪ ♪ What are you going to look at?

That star.

(Avianna) Yeah.

We're very interested.

♪ ♪ Oh, wait, it looks... A small white dot surrounded by other little dots.

Yeah, it's like this, then the little one.

Oh!

Oh!

Oh!

I just thought it was Jupiter for a second, just because it has like, moons.

Jupiter-- Galileo, when he looked through his telescope, one of the first things that he observed was Jupiter, and he saw that Jupiter was a circular sphere with a few other small things around it.

(Avianna) So I was right?

So that's Jupiter?

(Miranda) I was right?

(Tina) It's Jupiter.

Yea!

(Avianna) It sort of feels like New Year's Eve or Christmas because you always stay up late.

So it's kind of weird staying up past my bedtime.

I think that astronomers keep up their energy by drinking a lot of coffee.

Also I'm really tired.

I'm very tired.

(Izzie) And here's Avianna!

Hi, my name's Avianna, and this is my life.

I love to swim and play soccer.

I'm on a swim team that's called the Sea Dogs.

These are my trophies.

And I'm on a soccer team called Bays.

It's very fun.

A friend got me this for my birthday.

Actually, Miranda got me this on my birthday.

That's my karate medal.

I won first place.

Hi...ya!

(Izzie) And here we go-- on the move again!

(Miranda) When we got to site number 4, we got to see a lot of stars, but not as much as our darkest site.

(Avianna) When we looked at our data, at that point it kind of evened out.

We felt that it would be going down even lower as we got closer to the city.

(Tina) What did you guys find out?

(Avianna) We think that it's... (Miranda) Limiting magnitude 5.

Now that we finished site number 4, we're going to our last site in the city.

♪ ♪ (Miranda) So now that we're back in the city, I realized that there's a lot of lights on.

A lot of people are asleep at night, businesses are already closed, and still there's so many lights on that it's like, a waste of light and energy.

This is a very wasteful light.

It's like blinding yourself just by looking at it.

The good lighting that we saw was at the fire station.

It's shielded, and it's used downward like it's supposed to be used.

Let's go!

(laughter) ♪ ♪ Heading back into the city was very surprising.

(Tina) So already, how does the sky compare to our last location?

(Miranda) It's not as many stars, but...

I see the Summer Triangle.

It would be limiting magnitude 4, which is kind of weird because that's what we got before.

Here we got limiting magnitude 4.

After being in all these dark sites, all of a sudden we see all these lights.

It's very bright, and it's surprising.

We could actually see the sky glow.

Look-- all that sky glow.

Sky glow is a type of light pollution that you can see this little bubble across the city that is lighter than the whole other sky.

Oh look where's there's all those lights-- you can't see any stars.

Yeah, but if you go up, you can.

(Miranda) Yeah.

So I guess that that shows how much light pollution affects us.

(Avianna) Miranda and I, we were so bummed out that when we looked around, there was so much bad lighting, so we thought we could make a difference, so we went back to Miranda's house and made our own light shield.

Now we take off this part.

We can take this off.

Let's turn this on.

Okay, you obviously see that this is horrible.

We need to plan it.

How do you want the design to be?

It has to be curved down.

So you mean something like those cones that dogs wear?

It should be something like funnel-looking, cone.

We need to find the circumference.

7-- it says 7.

So it's kind of projecting it like that.

We are trying to make it shine on where you actually want it so that it doesn't have excessive light going everywhere.

If we tape it like this, right?

(Avianna) Yeah, and then we can cut around.

We used Miranda's constellation on her ceiling, so we turned off all the lights.

(Miranda) So why don't we just try our first one?

♪ ♪ Now you can't see any stars.

So if you had one like this, I mean, it would block some of the light, but you still can't see any of the stars, right?

Too bad.

What else could we use to make it not shine through like.

We can't use plastic because that doesn't work with heat.

Yeah, plastic will melt.

Wait, tinfoil.

The tinfoil basically is just going to lock in all the light so that it won't leak.

(Avianna) So, test it, Miranda.

Leaker!

Unleaker.

Yeah, this one is going to be a lot better.

So that's the...

Mall, it's the mall.

Let's just call it the mall.

(Avianna) Oh cool.

♪ Hallelujah.

♪ It's directed.

♪ Hallelujah!

Hallelujah!

♪ ♪ Wow!

(Miranda) Yeah, so if everybody shielded their lights... (Avianna) We would still be able to see some stars.

(Miranda) Yeah, but it's still good because we can actually... (Avianna) I love this light!

(Miranda) Avi and I are at our house.

We're just looking over our data and trying to figure out what it means.

71.70 degrees west.

So at our first location, we got limiting magnitude of 7.

And for the 2nd location, it was limiting magnitude 5.

One thing that Avi and I did notice is that if you have lights around you, you can't see stars.

So the less lights that you have around you, the more stars you can see, and the more lights that you have around you, the less stars you can see.

(Izzie) Got it!

So now I'm ready to help Jake.

What constellation did we see?

Cygnus, right?

Yeah.

Uploading our data was very rewarding.

(both) Latitude was... (Miranda) Everybody can do this.

I just got to help scientists all over the world.

So yeah, it was very cool.

(both) Star party!

(laughing & playful screaming) Welcome to our star party.

Yeah, welcome.

This is the pizza, people.

(Avianna) When I finished my roadtrip, I felt like a real astronomer, and I just felt so amazing and excited.

Before I entered the star count, I didn't realize how much light pollution was affecting the whole world, and now I know that I have to do something to change that.

Look, there's Jupiter!

(Tina) Oh my gosh.

Hey ladies!

Hi Tina!

Hi Tina!

Are you guys ready to look at more telescopes?

(all) Yeah!

Ooh, red lights!

I see Jupiter.

(Miranda) It was a great experience to do all this and have our friends here and share what we did.

(both) We finished!

♪ ♪ (din of the audience talking) Okay, so all you gotta do is skate and dance and leave the rest to me.

Oh man, your board is gonna shine!

Are you sure about that?

Oh, I am totally sure-- just trust me.

I do.

Good.

Then trust me about this too.

This move?

The bobblehead!

I made that up!

Yeah... don't use it.

(cheers & applause) Go, go, go go!

You're on!

No, trust me.

(click!)

Whoo-hoo!

(loud cheers & applause) Oh man!

Iz, thank you so much!

You're a real star.

So are you, Jake!

(loud cheers, whistles, & applause) Hey, I think they want an encore.

Whoa, ah, what should I do?

(both) The bobblehead!

(both laugh) This is a type of telescope called a Dobsonian scope.

It's a bit different from what you've been using before.

Those used a lens to focus the light.

I'll put the barrel down.

It's not a lens, right?

What is it?

(SciGirls) A mirror?

Mirror.

The mirror is not a normal flat mirror, it's actually concave, slightly curved.

This is a viewfinder through which we look at the objects in the sky.

Aim it, the telescope, looking through here first.

Where you want it?

Exactly, where you want to go, then you'll look through the eyepiece.

(SciGirls) All 4 of us love to cook.

The menu is collard greens and peach cobbler.

You guys, this is awful for you.

Our goal-- to make them more nutritious.

That was good!

The 4 of us have been in the May Day Parade every year.

This year we wanted to do a huge group puppet together.

And we could sort of engineer it to move.

Whoa!

Whoa, whoa, whoa!

I think I want a calm horse.

We're trying to figure out which horse would be best, scientifically, to be the smoothest ride.

Oh!

I love the one on the ground!

(Izzy) Major funding for "SciGirls" is provided by the National Science Foundation-- supporting education and research across all fields of science and engineering.

The National Science Foundation-- where discoveries begin!

(woman) Additional funding is provided by ExxonMobil.

♪ ♪