foreign [Music] that's a great idea yeah oh hey everyone
here in the United States it's almost time for Thanksgiving that's a day when
you get your friends and family together to eat a big tasty meal so squeaks
and I are planning dinner and making a shopping list so far we have mashed
potatoes cranberry sauce turkey green bean casserole I can't wait and we're
going to have some of our favorite foods a huge block of cheese for squeaks of
course and a delicious pumpkin pie for me oh wow that
's a great idea squeaks
squeak suggested we make some of our friends favorite food too that'll
make our dinner really special okay let's see who we have on our guest
list first up is Sam the bat [Music] oh hi everyone sorry about that I got to the Fort
pretty early this morning so I'm still a little sleepy Mr Brown hey Mr Brown oh hey good morning
Sam you're here awfully early yeah it's because I've made an amazing Discovery a space Rock check
it out whoa where did you find this well I was
up late last night looking at the stars per usual
but this time there were lots of shooting stars Bright Lights streaking across the sky and then
when I went outside this morning I found this super weird rock on the ground it didn't look
anything like the Rocks around it and it looks so cool and different I had to bring it in for
you to see I think it's from space let me see you know Sam I think this could be from space
well everyone I think it's time to do some meteorite tests when we loo
k up at the night sky
we mostly just see stars but if you had a really powerful telescope you could also see that space
is full of rocks just zooming around these rocks come in all shapes and sizes and sometimes they
get into the layer of air all around earth called the atmosphere and when they do they fall really
fast towards the ground in fact the Rocks fall so fast that they start to get really hot as they
move through the atmosphere and then they burn up and when they do they can leave
a bright streak
of light across the sky sound familiar Sam that sounds like the shooting stars I saw exactly when
those rocks are burning up in our atmosphere we call them shooting stars or meteors I mean they
aren't really Stars we just call them that because they're bright lights in the night sky like real
stars are most of the time those meteors burn up nearly all the way so there's almost no Rock left
but sometimes pieces of rock make it all the way to Earth's surface if they hit the gr
ound we call
the meteorites most meteorites are small usually no bigger than my hand and they're made out of
bits of Crystal or iron crystals aren't rocks but they look a lot like them they're hard usually
have lots of straight lines and are sometimes clear or a bit see-through in places a lot like
rock candy and iron is a really hard shiny metal okay so you're saying that this could be a
meteorite it could be but let's run some tests to find out there are a lot of different rocks
here on
Earth so there are some tests you can do right at home to see if you might have found
a real meteorite the tests have to do with the properties of the rock those are things you can
observe or notice about it like it's color and shape and you've already finished the first test
Sam what do you mean well the first test is to see whether your rock is is like other rocks nearby
does it match the other rocks in the area or does it stand out so Sam compared to other nearby
rocks was this one a dif
ferent color or Texture or shape none of the other rocks nearby looked or
felt like it the other rocks were all gray or red and they were all round all right let's move on
to the second test color meteorites get to earth after burning through the atmosphere and when they
burn they normally change colors it's just like how wood or paper turns black when you burn it in
a campfire so meteorites normally have a layer of black or dark brown color on the outside my rock
is really dark brown maybe
because it was burning in space alright so far so good but let's look
at shape next meteorites usually aren't perfect circles or squares instead they have irregular or
unusual shapes like they might look really lumpy but an important thing is they also feel smooth
and don't have any holes in them well this rock is shaped like a meteorite and it doesn't have
any holes in it but it's not that smooth all right let's take a look at the next test then this
is a test to see how dense the rock is
we say an object is really dense when it's pretty small
but also really heavy for its sides if you pick up a small object and it's way heavier than it
looks that's probably a good sign that it's dense meteorites are really dense so they have a lot of
stuff packed into a small space this makes them a lot heavier than Earth rocks that are the same
size I actually brought some rocks in from the garden earlier this morning so I could learn more
about them so we can compare how heavy they feel
so how heavy does it feel compared to my rock
you know your rock does feel pretty heavy I think it's pretty dense whoa does that mean it's
a meteorite let's do one last test just to be sure we're gonna test if your rock is magnetic do you
remember what meteorites are made of Sam totally they're made of crystals or metal that's right
most meteorites have the metal iron in them and iron sticks to magnets when something sticks to
a magnet we call it magnetic so if this rock is a meteorite then
the iron in it should make
this magnet stick to the Rock let's try it look at that whoa It's magnetic so let's
see what we learned this is an unusual Rock and it's the right color to be a meteorite it
also has a good irregular shape like a meteorite it is a little rough but it also doesn't
have holes it's also pretty dense and is magnetic what do you think Sam hmm that sounds
like a meteorite to me you know I think you're right even if it's not super smooth it checks
all our other boxes s
o wow congrats Sam you found a space Rock whoa thanks Mr Brown I
had a lot of fun learning about my rock too meteorite testing with you is really cool and I
learned a lot actually now I want to go see if there are any other meteorites outside I'll
catch you later I'm glad you enjoyed it bye Sam bye Sam the bat loves space and I happen to
know that he loves spaghetti so what if we made him a spaghetti and meatball solar system with
different meatballs for all the planets foreign bugs so I'll
need to make mosquito meatballs
I'll need to find a recipe for that okay next up is our neighbor Mr Brown oh hi everyone
squeaks is supposed to meet me here in the lab but he's not here yet I wonder what's taking
him so long I'm super excited to see him because he promised he'd show me his new magnet oh
there you are squeaks is everything okay oh I see squeaks was trying out his new
magnet by the river and the panther is really long and windy so it took him a while
to find his way back to
the fort the Ripper is directly south of here if only you had had
a compass then you could have taken a shortcut a compass it's a tool that can tell you what
direction you're going and if you know what direction you're going you can find your way
around without getting lost people have been using compasses for thousands of years to explore the
world they can be big or small fancier plain but they have an important thing in common they have
some kind of Arrow or needle that Points North so
if we had a compass right now it's needlewood
point this way because that's North in fact we can use your magnet to make your own Compass
right here at the Fort what do you say squeaks all right let's do it you can make a compass too
just make sure you get a grown-up to help you to make a compass you'll need a sewing needle a
piece of aluminum foil and a clear container of water with a flat bottom oh yes and a magnet
thanks squeaks this is definitely where you'll want help from a grown-up f
irst carefully pick
up the sewing needle and hold it by the end that has the hole in it now drag the magnet along
the needle slowly from the end with the hole to the pointy end like this you'll need to do
this about 15 or 20 times and always make sure you're doing it the same way from the whole end
to the needle point next we'll need to fold our foil into a little boat of sorts and then poke
the needle through it again make sure a grown-up helps you with this trust me poking your finger
wi
th a needle hurts now we're ready to finish our Compass all we have to do is gently float the
foil on the water in our Bowl wait a second and look the needle turned and it is now pointing
North we did it good question squeaks but before I explain what happened in this experiment let
me explain how compasses work in general the reason why a compass Points North is really
cool it's because the pointy part inside is a magnet and magnets have two ends called poles
one end of the magnet is calle
d the North Pole and the other is called the South Pole no matter
which direction they're facing and opposite poles of two different magnets attract that means they
pull on each other meanwhile similar poles repel each other repel means push away now here's
the really awesome part our planet Earth is basically one huge magnet so it also has magnetic
poles that means the Earth's poles act the same way that a magnet's poles do they attract and
repel the poles of other magnets and they just so
happen to line up pretty well with the parts
of the planet we call the North and South Pole the Earth's magnetic poles pull and push a
compass needles magnetic poles and that's what causes the compass to Point North so why
do you think our sewing needle pointed North that's right I said the needle
of a compass is a magnet so that's it our sewing needle became a magnet
that first step we did where we rubbed the needle with your magnet actually magnetized the
sewing needle in other words it
turned it into a magnet the pointy end became the North Pole of
a magnet and the other end became the South Pole you know squeaks you're absolutely right it seems
like the North Pole of the earth should repel the North Pole of our compass needle but here's the
weird thing the Earth's north magnetic pole is actually in the South and its South magnetic pole
is in the north so the Earth's South magnetic pole is pulling the North Pole of our needle to the
North and the Earth's north magnetic p
ole is pulling the South Pole of our needle to the South
which is weird and confusing I know but hey I didn't name these things exactly squeaks since the
Earth's magnetic poles are always pulling on the poles of other magnets all we had to do to get our
magnetized needle to Point North was let it freely spin about in response to those forces which is
what the foil and water were for cool huh [Music] oh whoa look at the time we told Jesse we'd
meet her in the garden to help pull weeds so we
better get going and we'll look into
getting you a compass that's a bit easier to carry around than this bowl that way you can
make your way to and from the river a little quicker next time Mr Brown loves camping and
roasting things over the campfire like hot dogs and marshmallows so even though they aren't
really traditional Thanksgiving Foods let's make Mr Brown a whole bunch of hot dogs and we can
have a fire in the backyard after dinner and make s'mores for dessert what do you think all
right next up are Bill and Webb the duck twins what's going on what's all this quacking about
well we were in Sam the bat's Observatory and there was a button really high up on the wall that
we really wanted to push to see what it would do yeah and neither of us could reach it but I told
Bill about something called engineering that could help us wow that's a great idea engineering
is how people develop solutions to problems first Engineers identify a situation they want to
change and then
they design and test solutions to the problem yeah it sounded cool so you identified
the problem you couldn't reach the button and you decided to approach the problem using engineering
what happened next well we each designed a high up button Pusher to help us try to reach the button
but I think the web site all right settle down YouTube I bet both of you came up with some
great designs why don't you show me what you made I have my design right here you can you can
eat that I nailed severa
l long pieces of lumber together I can reach some high buttons wow bill I
can see that your design is very strong and stiff it would be great for reaching things that are far
away like that button but it also looks very heavy I can imagine it might be hard for you to lift
this one up yeah it was a little little hard to handle when I was testing it in the observatory
well look at mine it's nice and lightweight just taping a stick at the end web yours does look
very light which would make it
very easy for almost anyone to use but it's a little bit
floppy don't you think it was very easy to do well you know the best part about engineering
is that there can be more than one way to solve the same problem you both came up with solutions
to the problem and both of them had strengths and weaknesses when you tested them out let's think
about what those were bill yours was strong but hard to use Webb yours was easy to use but super
flimsy but that's okay because finding a really good s
olution to a problem sometimes takes a few
tries even Engineers have to test their designs to see what's working and what's not working
and make them better Orville and Wilbur Wright were two brothers who made the first airplane
to fly in the sky but before that they tested many designs first they made gliders that could
only glide through the air instead of flying then they added engines so those gliders could stay
up in the sky and they had an airplane maybe we can take a little bit from
each of your designs
and make an even better high up button pusher what if we use the tape from mine to tape small
lightweight pieces of wood together yeah then it would be strong like mine but lightweight
like Webb's design great ideas you two let's build a new design that combines a little bit
from each and see how it does wow look at this great design that you worked together to make yeah
it's still made of strong wood just smaller pieces the small pieces of wood help make it lightweight
so anyone can lift it up great work you two using your engineering and teamwork skills to create an
excellent solution to a problem let's head to the observatory to test it out yeah if there's one
thing I know about Bill and Webb aside from that they love to argue is that they have two favorite
foods the first one is gummy worms and the second one is earthworms so I'll make a big bowl of each
oh good thinking I better get them each their own bowls or else they'll spend all of dinner fighti
ng
over them next is Dino the cuckoo bird hey there squeaks and I are here with our friend Dino and
our library just got a new book that has pictures of all the different kinds of dinosaurs that used
to live on earth and it tells a little about them too like what they ate this page says that some
dinosaurs like stegosaurus and triceratops ate plants so I was thinking that they must have
been friends who hit up the salad bar together uh do you know but they definitely weren't friends
with t
he meat eaters like Allosaurus and T-Rex I bet they had amazing dinosaur races as they ran
to catch the best food Dino yes Jesse what what do you think I think think that it's fun to
imagine what these animals might have done if they'd met and I also think we need to remember
that stegosaurs and Triceratops weren't around at the same time wait wait what I'm sorry dino
but the same is true for Allosaurus and T-Rex these dinosaurs lived in different times from one
another I don't get it they
all lived back at the time of the dinosaurs right yep you're right
about that but the time of the dinosaurs was a very long time it lasted millions of years
so all dinosaurs didn't live at the same time oh good point squeaks we build a pretend time
machine to imagine what it would be like to travel back in time and see living things from the past
but to see all of these dinosaurs we would have to make more than one trip so if we took your time
machine back to the time of the dinosaurs we'd
actually have to go to lots of different times
exactly scientists divide dinosaur time into three parts called periods there's the Triassic period
which started over 200 million years ago some small dinosaurs like Eoraptor lived then next came
the Jurassic period Allosaurus and stegosaurus were alive during this period the Jurassic period
lasted over 50 million years it was after that that dinosaurs like triceratops and T-rex came
along in a Time called their Cretaceous Period oh you're rig
ht squeaks it can be pretty hard
to think about long periods of time like that but I have an idea we can use to show how long
ago dinosaurs lived we can use our bodies as a model we use models to help us understand or
explain something in the world around us by using our bodies as a model of dinosaur time
we can get a better picture of just how long ago those different periods were it won't
be perfect but it will be a way for us to think about things that happened a long time
ago now let's
say the bottom of your shoes is the bottom of our model when the very first
dinosaurs appeared that's the beginning of the Triassic period about 245 million years ago okay
stegosaurus and Allosaurus didn't show up until the Jurassic period about 50 million years
later that means that these dinosaurs would have lived in the time that starts somewhere
below your knee and ends somewhere around your hips that disc on your body represents about
56 million years then it was T-Rex time the Cretac
eous Period was about 74 million years
long that means if it starts at your hips it should end at about your chest and the time
of the dinosaurs ended about 65 million years ago so everything from your chest to the top of
your head represents the last 65 million years good question squeaks humans and their ancestors
have only been on Earth for about 6 million years so in our model that would be only the last
couple centimeters of your body maybe from the top of your forehead up wow so peopl
e haven't
been around for very long at all no life on Earth was around a long time even before there were
dinosaurs and I mean a long time and over that time the way Earth looked and the plants animals
and other kinds of life that lived here changed a lot some of these changes happened very fast
like volcanic eruptions but others happened very slowly so slow that we wouldn't have noticed
they were happening even if people had been around oh great question squeaks wants to know how we
know
plants and animals lived during different times if no one was there to see them I think I
know this one is it because of fossils good job Dino we found fossils bones Footprints and other
things left behind by ancient animals plants and other kinds of life we use these fossils as Clues
to try and figure out how long ago they might have lived oh well one way we can tell which fossils
are older and which are newer is by How Deeply they're buried think about paper in a recycling
bin the paper t
hat you put into the empty bin last week is on the very bottom of the can and it
gets buried by the paper you throw in later the very top layer of paper in the recycling bin is
the paper you put in there today this morning or even a few minutes ago oh I see so the fossils
that are deep in the ground like stegosaurus are older than the ones closer to the top of the
ground like the T-Rex that's right T-Rex is pretty young well in dinosaur Years anyway yes now let's
see what else we can learn
about in this new book this is an easy one Dino loves dinosaurs more than
anything else in the world so we'll make him some of my famous bird seed cookies and cut them into
the shapes of dinosaurs oh don't worry squeaks I'll make some chocolate chip cookies too and last
is our friend Grady the tardigrade hi everyone I was just working in the fort's greenhouse and
squeaks I have some good news the plants are doing really well pretty soon we should be able
to make a yummy salad out of the veg
etables we're growing gardening can be a bit dirty but it's
worth it as I was cleaning up I started thinking that maybe we should take a closer look at the
dirt our plants grow in what we often think of as just dirt especially when we have to clean up
is really interesting scientists would actually call the dirt in our Gardens soil and it's
home to an incredible number of living things oh that's right squeaks we can see a few animals
like earthworms when we're digging in the garden and they
're super important they help the plants
in our garden to get the air and food they need to grow but there are other living things in the
soil that we can't see with our eyes we need tools like this microscope to see them let's give it
a try howdy up there I had a feeling I was being watched oh hi we didn't mean to startle you I'm
Jesse and this is squeaks we're hoping to learn more about the kinds of living things in soil well
you sure have come to the right place name's Grady glad to meet
you I'm what's called a tardigrade
some people like to call my family and I water bears or Moss piglets but we're our own little
group of living things emphasis on the little most of us are only half a millimeter long about
the size of a period at the end of a sentence so we tend to get overlooked a lot well I'm sure glad
we didn't Overlook you would you mind telling us a little bit about your neighborhood well it would
be my pleasure the soil I live in is a mixture of things like water sm
all pieces of rock and air
it also has a lot of what we call organic matter that's our fancy term for things that either
were alive like the remains of dead plants and animals or are alive like me I'm one of billions
of Critters that can be found in a single spoonful of soil wow that's a lot of living things in such
a small space there are about seven billion people but they're living on the entire planet and not
only are there a lot of us in the soil there's also a lot of different kinds o
f living things we
call the different living things in an area it's biodiversity the bio part of the word means living
and the word diversity means different things and soil has a whole heap of biodiversity there are
more different kinds of living things beneath your feet in the soil than there are above the ground
that's amazing what's even more amazing is how the living things in the soil and life above the soil
are are connected take the plants in your garden for example they're stuck in
the ground by roots
and those roots also help them slurp up things they need like water but they also release stuff
into the soil like sugar microscopic living things called bacteria can use this sugar to grow and in
return some kinds of bacteria release things that the plants need well that's a win-win and that's
only one example other living things called fungi also work together with plant roots fungi is
a science word for the group of living things that includes mushrooms it's kind of
like how we
talk about plants or animals there are actually millions of different kinds of fungi including
the ones we see growing out of rotten logs when we hike or the tasty mushrooms we like to eat just
talking about fungi makes me hungry for some yummy mushroom soup exactly though these fungi I'm
talking about in the soil don't look like the ones you put on your plate they grow in super
thin strands that extend outward from a plant's roots in fact they kind of act like extra roots
that
help the plant pull things from the soil it is kind of nice of them isn't it of course
they benefit too in return for helping out the plant gives the fungi some of the food it
makes and other useful things it's a sweet little partnership though not all soil fungi and
bacteria hitch themselves to Roots some get energy by breaking down the dead plants and animals I
mentioned earlier they're what we call decomposers you can think of decomposers as the soil version
of the workers that pick up
the recycling in your neighborhood think about what would happen if
no one was ever there to pick up recycling oh it would pile up and so would dead plants and
animals if decomposers weren't around I agree squeaks that would be terrible decomposers sound
super important they sure are they also matter because lots of soil dwell in animals eat them so
in addition to cleaning up our neighborhood the decomposers that live in soil are an important
source of food for Critters like worms and and t
ardigrades like me then after we eat them the
waste we produce acts as a fertilizer helping plants above the soil stay healthy wow I didn't
know that our garden owes so much to all the tiny things that live in the soil thanks Grady don't
mention it now if you'll excuse me it's supper time and I had my eye on some tasty fungi so y'all
have a nice evening thanks you too bye squeaks how about we go ahead and put our soil back in the
greenhouse and then we can have our dinner too tardigrades ar
e Hardy microscopic animals that eat
all kinds of microscopic stuff like bacteria so I guess add bacteria to the list and we'll figure
that one out later okay sweets it looks like our shopping list is ready I can't wait to surprise
our friends with all of their favorite foods even if some seem a little weird to us I'm sort of
excited to try a mosquito meatball thanks for joining us today if you'd like to keep learning
and having fun with me squeaks and all of our friends make sure to hit th
e Subscribe button and
we'll see you next time here at the fort [Music]
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