National Park Service

U.S. Department of the Interior

Natural Sounds & Night Skies Division
Ask a Ranger at a visitor center if the park will have an astronomy program or telescope 

viewing while you are visiting. If they will, attend one of these programs. 

If not, make sure to do the “Take a planet walk” activity found within this book. 

How old are you? ____ That is the number of activities you must complete to become a 

junior ranger night explorer, but feel free to do more. 

Each activity is rated by difficulty:

 ages 5 and up.

 ages 8 and up.

 are the most challenging.

Look for the star ratings throughout the book and choose the activities that are right 

for you!

Also be sure to check out the bold italic words and their definitions throughout the book.

EXPLORE • LEARN • PROTECT

Night Explorer

How to become a

Junior Ranger

2009, Junior Ranger, Night Explorer. An explorer’s activity guide for ages 5 to 12.

Office of Interpretation and Education • Intermountain Region • National Park Service.

2013, Revision by NPS Natural Sounds & Night Skies Division, Fort Collins, Colorado.

Content — Claire Thoma, Chad Moore, Teresa Jiles, and Angie Richman.

Edits — Tawnya Schoewe and Cecilia Leumas.

Graphics — Chad Moore, Lisa Lynch, and Richard Kohen.

Layout & design — Richard Kohen and Angie Richman.

Cover artwork — Richard Kohen, hand model Laura Kohen, age 10. Cover photo — The Milky Way above Long’s Peak, 

Rocky Mountain National Park, by Tyler Nordgren.

Midwest Region Version Cover artwork — The Milky Way, Voyageurs National Park, by Tyler Nordgren.

Images — Courtesy NASA image archives.

Planisphere — Use of the planisphere courtesy National Research Council Canada.

Support has been graciously provided by Curecanti National Recreation Area, the National Park Service Night Skies 

Program, and the Student Conservation Association.
Exploring with your senses

The 24-hour pattern of light— day, sunset, night, and sunrise affects 

the daily rhythm of all living things. Most humans go to sleep 

when it is dark, but there are many creatures that wake up when 

we go to bed. In fact, there is an entire nocturnal ecosystem that is 

an important part of nature. These nocturnal animals have adapted to 

the night. For example, bats bounce sound waves off objects to fly in the dark and catch 

insects. Deer, owls, and mountain lions have large eyes to let in more light, and can see 

just fine by starlight.

Nocturnal 

describes an animal 

that spends its “days” at 

night.

Spend some time outside in the park during 

the day, as the sun is setting, and at night. 

Record the differences in what you see, smell, 

and hear at each time of day.

 Record one sense.

 Record two senses.

 Record three senses.

My observations NIGHT

SUNSET

DAY
Astounding Sun

Our sun, which is named “Sol,” is the 

nearest star to us and is the brightest star in 

the sky. Like all stars, Sol is a giant ball of super 

hot gas. It is so big that one million Earths can fit inside! Special telescopes and satellites 

that are made for looking at the sun show us that its surface is always 

changing. Surface explosions called prominences shoot hot 

gas into space and Sunspots appear as dark spots. Over time 

they will change places on the surface of the sun. 

Remember, never look directly at the sun!

The sun shines light in all the colors of the rainbow. 

It also shines other types of light like ultraviolet and 

infrared. Our eyes cannot see ultraviolet light, but we 

know it exists because it will burn our skin if we stay 

outside too long without sunscreen. Other types of light 

from the sun are even more harmful. Luckily for us the 

Earth is protected by an atmosphere that contains ozone, 

which blocks ultraviolet and other harmful types of light.

Prominences 

Activity on the Sun where super-hot gas is 

shooting off of the surface and then falling back down 

in an arc or loop.

Sunspots are areas where the surface of the Sun is a bit 

cooler, which will appear darker than the rest of 

the surface.

Ultraviolet 

light is light from 

the Sun or stars that we 

cannot see with our eyes 

because it is so blue. This is 

the type of light that gives you a 

sunburn!

Infrared light is light from the Sun 

or stars that we cannot see with 

our eyes because it is so red.

infrared light

visible light

ultraviolet light

 Label a sunspot, a prominence, and the ozone layer on the picture above.

 Do the above and think of another type of harmful light that the atmosphere blocks. 

 (Hint: It is used in hospitals to look at your bones!) What is it? ____________________
Stargazing is great, but it is always more 

fun when you are prepared!

• Wear warm clothes. It can get cold 

and windy at night. 

• Bring water, a snack, and a chair

to sit on.

• Use a red flashlight to move 

around at night. (White light will 

spoil your night vision.)

• Bring a starchart or planisphere 

to find the constellations.

• Use binoculars to look at 

planets and star clusters. 

• Try not to bump stargazers’ 

telescopes or touch the 

eyepieces. 

• Most importantly, bring lots 

of time and curiosity! 

Find five of the orange words in the word search puzzle. (Hint: Look for vertical, 

 horizontal, and even backwards words.)

 Find all of the the orange words in the word search. 

 Find all of the the orange words in the word search.Then look at the letters in the word

 search table that are not circled. Starting with the first letter, write each leftover letter on

 the blanks below to discover the hidden message. (Some of the letters are already 

 written for you.)

M v t 

 e 

a S ,

 t 

 t p 

 !

M A N C H A I R Y V I S B

N I G H T V I S I O N I I

T O R S T S N A C K R H N

T I W N K T T H E P E A O

E R A K E A X P E R D I C

L E R N C R E E N D F S U

E A M F T C E R T H L E L

S S C U N H G O E S A D A

C O L W N A B U T T S H R

O E O R E R I S J U H S S

P T T W A T E R A S L M U

E C H H C U R I O S I T Y

S T E O S E E I N T G H E

P A S R K A F T E R H D A

G N I Z A G R A T S T R K

Word search

Smart stargazing
Where should 

the light go?

Humans are creatures who have adapted to do most of our 

activities during the day. When we do things at night, we need 

light. But, light is a tool we must learn to use responsibly. 

Outdoor lamps are often too bright or point up into the sky. 

They add to light pollution, and when light pollution is really bad, 

we cannot see the stars and nocturnal animals may be harmed.

Light 

pollution 

is the brightening of the 

night sky by man-made 

lights.

This lamp protects the 

night sky and animals 

by only shining light 

down to the ground.

This lamp wastes light 

into the sky: it goes 

everywhere!

This lamp shines light 

everywhere except 

where it is needed: on 

the ground.

Mark an “X” over the wasteful 

lamps (left) and circle better lamps.

Draw an “X” over wasteful 

lamps and circle good ones. Draw a 

triangle around one that is like what What do the lamps at your home look like? you see at this park.

Nocturnal animals

 Draw a line from each picture to its description.

 What can you do to help the nocurnal animals where you live? _________________________________

__________________________________________________________________________________________________

I am unable to resist being drawn to a light, and may fly for 

over a mile to your porchlight.

I used to find my favorite foods- moths and gnatseverywhere I flew. But now I must commute much further 

to the city for my dinner.

Lights from tall buildings and houses confuse me during 

migration each fall. I must be careful, or I can crash into 

one of those shiny bright windows

My flickering tail will attract a mate, but only if she can see 

me among the many streetlights.

Firefly

Bat

Moths

Warbler
How dark is the sky?

The stars are always there, but we cannot always see them. The farther 

away from sources of light pollution you are, the more stars you can 

see. Astronomers measure the darkness of the sky in something called 

limiting magnitude, where 7 is the best and 0 is the worst. Follow the 

directions below to estimate how dark the sky is at this park.

Big Dipper

Magnitude 2 Magnitude 4 Magnitude 6 Magnitude 7

Limiting 

magnitude is 

a measure of the 

darkness of the night 

sky based on the faintest 

star that can be seen 

with your eyes.

Orion

 Below are pictures of how many stars you can see at different limiting magnitudes. Choose 

the picture you think best matches the sky at this park and circle it.

(Hint: If it’s summer, use the Big Dipper. If it’s winter, use Orion. Also use the star wheel in the 

center of the book to help you find these constellations.

From your home, which picture matches the sky from your backyard: __________________

Can you see more or fewer stars at your home? Why do you think this is? ______________________ 

_________________________________________________________________________________________
Telescope eyes

If possible, attend an astronomy program and telescope viewing.

Changing faces of the Moon

It takes 28 days for the moon to complete an orbit around the earth. As 

it travels around our planet, different sections of it are lit up. When the 

whole face of the moon is lit, it is called “full.” When none of the moon is lit, it is called 

“new.” While the moon is growing from “new” to “full,” it is described as “waxing.”

When the moon is shrinking from “full” to “new,” it is called “waning.”

 Go outside and find the moon. Shade in the shadowed 

 part in the circle to the left.

 What phase is the moon in now? ______________

 Predict the number of days until the next full moon: _____

New Moon

Waxing 

Crescent

First 

Quarter

Waxing 

Gibbous

Full Moon Waning 

Gibbous

Third 

Quarter

Waning 

Crescent

Orbit

is the path, 

usually an oval, of a 

moon around a planet or 

a planet around a star.

 Look through a telescope. In a circle (below), draw what 

 you can see in the field of view.

 Ask the telescope operator to tell you about the object, and

 write down what you learn. 

Look at a second object in the telescope and repeat the 

 activity.

Field 

of view 

is the piece 

of sky you can 

see through a 

telescope.

Object name: _______________________

Object type: ________________________

One thing I learned about this object: ____

______________________________________

______________________________________

Object name: _______________________

Object type: ________________________

One thing I learned about this object: ____

______________________________________

______________________________________
Using a planisphere Constellations

are groups of stars that make a 

picture in the sky.

Use scissors to cut out the planisphere. Cut just outside the thick border.

 Cut out the star wheel (planisphere) below and the holder (on the 

next page). Carefully cut out the middle of the holder. Fold the flaps on the 

holder back, and insert the star wheel. Turn the wheel until the date appears 

above the time that you are out at night. The constellations visible at that time appear 

in the window.

Face South and hold the planisphere above your head and look up at it. The constellations in the middle of 

the oval should be directly above your head (at the zenith). The constellations on the left side of the oval 

should be to your left on the eastern horizon. The constellations on the right side of the oval should be to 

your right on the western horizon. The stars on the bottom of the wheel (South) should be directly in front 

of you, and those on the top of the wheel (North) should be behind you.
The stars in the upper corners change color from page to page. Stars come in 

many different colors, and their color tells us what temperature they are. Hotter 

stars are blue, while ones that aren’t so hot are red. Our star, the sun, is yellow, 

and is a medium temperature star. Really really hot stars shine in ultraviolet light, 

while those that are only warm emit energy as infrared light.

A star can change color by changing its temperature. As stars grow older they 

often cool down in temperature and thus may appear more red. By studying the 

colors of stars, astronomers learn about their birth, life, and death. Check out the 

Star Formation Jumble to learn more.

Did you notice?

Our sun is the nearest star to us. Its 

surface temperature is 10,000°F!
Planisphere activity provided courtesy of the National Research Council Canada

Use scissors to cut out the 

planisphere’s green holder.

Hint: Use a red-light flashlight

to read your star wheel in the 

dark. You can make your own 

red flashlight by covering a white 

flashlight with red cellophane or 

fingernail polish. 
Planisphere activity provided courtesy of the National Research Council Canada Earth
Solar system smarts 

 This is a picture of our solar system. Label each planet to see its location from the sun.

Not to Scale

Illustrations: NASA/XCX/M. Weiss

M ––––– –

V ––– –

E ––– –

M – – –

J ––––– –

S –––– –

U–––– –

N – – ––– –

Planets

Saturn

Uranus

Earth

Neptune

Venus

Jupiter

Mercury

Mars

 Create a mnemonic to help you remember the order 

of the planets: ____________________________________

________________________________________________

________________________________________________

________________________________________________

_________________________________________________

_________________________________________________

A mnemonic

(pronounced “ne-mon-ic”) is a 

sentence in which the first letter of each word is 

the same as the first letter of the words you are trying 

to remember. For example, to remember the first four 

moons of Jupiter (Io, Europa, Ganymede, Callisto), 

many students remember the phrase, “I Eat 

Green Caterpillars.”

Where is Pluto?

In 2007, scientists changed 

the definition of a planet, 

and Pluto ended up moving from the 

category of “planet” to the category 

of “minor planet” because:

• 1) Pluto has an irregular (not 

circular) orbit; and

• 2) Pluto did not clear its orbital 

path of debris.

Based on these definitions, scientists 

either had to demote Pluto or add 

several more planets to our solar 

system.

Take a planet walk Start at a trailhead and pretend you 

are starting at the sun. While you walk, the 

planets’ distances from the sun would be the 

number of steps you take. Place a rock or 

other object in the location of each planet. 

This walk is a total of 484 steps. The sun 

would be the size of an apple and the earth 

the size of the point of a pin on this scale.

4 steps: you are at Mercury 

4 steps: you made it to Venus

4 steps: you have reached Earth

6 steps: you are at Mars

45 steps: welcome to Jupiter

54 steps: you have arrived at Saturn

118 steps: you are at Uranus 

134 steps: you have reached Neptune

115: you made it to Pluto!
Navigating at night

For over a thousand years, sailors have used the stars to 

find their way across the ocean on long voyages. As the 

earth rotates, all of the stars appear to spin around a point 

called the Celestial Pole. Because the star Polaris (also called the 

North Star) is very close to the Celestial Pole, it is the only star that 

does not appear to move during the night. Its altitude is equal to the observer’s latitude

(these distances are measured in degrees). Sailors could find their latitude by measuring 

how far above the horizon the North Star appeared. To test your own skill at navigating 

by the stars, go outside at night, and use the chart below to find Polaris. 

Now hold your arm out straight and level to the ground. Make a fist with 

your thumb resting on top of your first finger. Starting with the base of 

your fist straight out in front of you, count how many fists you need to 

reach Polaris.

 Look for the 

North Star in the sky. 

Did you find it? 

______________

 Estimate your 

latitude using the 

North Star. Remember 

that one fist is 

about 10 degrees. 

______________

 Look at a map 

or ask an adult to help 

you find your exact 

latitude.

How close were you? 

______________

The Big Dipper

The Little Dipper

Cassiopeia

North Star

(Polaris)

follow the pointer stars

or look for the ‘W’

This side up for winter evenings

This side up for summer evenings

This side up for spring evenings

This side up for fall evenings

Latitude

is the 

distance from 

any point on the 

Earth to the equator. 

The equator has 

a latitude of zero 

degrees, and the 

North Pole has a 

latitude of 90 

degrees. 

Altitude

is the height that 

an object appears above 

the horizon. An object on the 

horizon has an altitude of zero 

degrees, and an object directly 

overhead has an altitude of 90 

degrees. 
Constellation riddles

 Draw the shape of each constellation by connecting the numbered stars in order.

 Connect the stars and write the name of each constellation next to its story below.

1

2

3 4

5

6

7

8

9 10

13 12

11SUMMER

I am a mighty hunter. I hunt with a bow and carry a sword in my belt. I am usually 

seen during the winter because I stay away from my enemy, the scorpion, who is 

visible in the summer. Who am I?....

I am a lion with a bright heart. Although I am lying down right now, I am still a 

fearsome beast seen during the spring and summer. Who am I?....

I am the scorpion whose powerful claws and stinger chase the hunter across the 

sky. I am on a mission to chase him forever. I am seen in the southern sky during the 

summer. Who am I?....

I am a beautiful queen whose pride almost killed my daughter, Andromeda. I can be 

seen sitting in my “W”-shaped throne in fall, but as punishment for my pride I hang 

upside down half of each night. Who am I?....

I am half horse and half man, although now people often refer to me as a “teapot.” I 

tutored the great heroes Achilles and Hercules. I guard the southern sky in summer. 

Who am I?....

I am a swan, and I gracefully glide down the Milky Way during summer and fall. I am 

sometimes known as the “Northern Cross.” Who am I?....

n

p

c

g

c

1

2

3

4 5

6

8

9

10

11

12

13

14

7

WINTER

1

2

3

4

5

6

7

8

9

SUMMER

10

1

2

3 4

5

6

7

8

9

10

SPRING

1

2

3

4

5 6

7

8

SUMMER

1

2 3

4

5

FALL

Cassiopeia

Scorpius

Leo

Orion Cygnus

Sagittarius
Same stars, different stories

People around the world make up different 

stories about the shapes they see in the stars. 

The constellation we know as the Big Dipper 

was known to both Native Americans and 

Greeks as a big bear. To farmers in England, 

it was known as a plow, and to fishermen in 

Australia, it was known as a canoe. Germans called it a big 

wagon, Arabians saw a coffin followed by three mourners, 

and the Chinese knew it as a grain measure. People see 

objects that are important to their way of 

life in the stars.

 Make 

up a story 

about your 

constellation.

Grain measure

Canoe

Plough Bear

 Using 

the starfield 

to the left, 

connect some 

stars to make 

your own 

constellation.

MY STORY
Deep-sky match

Scavenger hunt

tic-tac-toe

Draw a line from each picture to its description.

Many galaxies living in the same 

neighborhood

Ball of ice and dust that passes

by Earth and often has a “tail”

of gas streaming out behind

Group of tightly packed old, yellow stars

Two stars that orbit each other

Gas left behind when a star’s core 

collapses (through old telescopes, it 

looked round like a planet)

Thick cloud of gas from

which new stars can form

Gas, dust, and billions of stars in a 

flattened shape with spiral arms

Chunk of rocky debris usually found 

between the orbits of Mars and Jupiter

Galaxy cluster Binary star system

Star-forming nebula Comet

Globular cluster Spiral galaxy

Asteroid Planetary nebula

 3 matches

 5 matches

 8 matches

Go out at night, let your eyes adjust 

to the darkness, and look around. 

Cross off everything that you find!

 Three objects

 A line of three objects

 Two lines of three objects

Planet Star cluster Shooting star

Star Night animal Moon

Man-made light Milky Way Satellite
Star formation picture jumble

Stars have life cycles just like plants and animals! All stars begin from thick clouds of 

gas and dust. In their first stage, they are called protostars and are surrounded by a 

disk of gas and dust. The size of the star determines what type of life it will lead and how 

long it will live. Red dwarf stars are smaller than our Sun. Because they live for so 

long, they have not yet evolved past their first life stage. A Sun-like star spends most of 

its life as a yellowish ball of gas with burning hydrogen in its core. Once it uses up 

all its hydrogen, it evolves into a red giant before its core collapses and leaves the gas 

behind to form a planetary nebula . Its core then becomes a white dwarf and 

slowly cools. A star a bit larger than the Sun will live as a white giant and evolve into 

a red supergiant , and may explode in a supernova . A star much larger than a 

white giant will spend its short life as 

a blue supergiant that evolves 

into an even bigger red supergiant. 

 It finally collapses into a powerful 

black hole . All of the gas that gets 

sent out into space by supernovae 

and planetary nebulae eventually 

forms clouds of gas and dust that 

become nurseries for new stars, and 

the cycle continues.

 In the picture jumble on the left, 

find the sequences that represent the 

life cycles of each of the four types of 

stars. The sequences may be vertical, 

horizontal, or diagonal. Write the number 

found in the corner of each picture in the 

blanks below and do 

the math (addition and 

subtraction) to discover 

how many millions or 

billions of years the star 

will live.

Red Dwarf: ___ + ___ = ___ billion years

Sun-like Star: ___ + ___ + ___ - ___ - ___ = ___ billion years

White Giant: ___ + ___ + ___ + ___ = ___ million years

Blue Supergiant: ___ + ___ - ___ - ___ = ___ million years
A-Mazing galaxy

Our solar system and all of the stars that we can see with our eyes are part of a spiral 

galaxy named the Milky Way. The Milky Way can only be seen when it is really dark. 

Have you ever seen the Milky Way? It got it’s name because the ancient Greeks thought it 

looked like spilled milk flowing across the sky.

An artist’s idea of the Milky Way. The Milky Way as seen from Earth.

 Can you find your 

way from the outer 

edge of the galaxy all 

the way to the giant 

black hole in its 

center?
As a Junior Ranger – Night Explorer, I promise to enjoy and protect 

the night sky by exploring my nighttime environment, not disturbing 

anything wild and using light responsibly. 

Junior Ranger Signature _________________________ Date ____________

Park Ranger Signature __________________________ Date_____________

Junior Ranger

Night Explorer

EXPLORE • LEARN • PROTECT