sky maps teacher's guide

Northern Stars Planetarium, 15 Western Ave., Fairfield, ME 04937 207-453-7668Teacher's Guide for "Sky Maps" www.northern-stars.com

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Sky Maps Teacher's Guide

This Teacher's Guide will help you prepare your students for their upcoming visitto Northern Stars Planetarium when it visits your school. The show Sky Maps willexamine several basic ways of finding stars, planets, and deep sky objects in the nightsky.

We will begin with our All-Sky World Map and discover how we are able tolocate places upon the Earth using conventional maps. Using similar methods we willthen move on to the night sky. By simply pointing and trying to describe a sky object wediscover the need for a better way of finding things. Students find that using the cardinaldirections and altitude improves our ability to locate. Adding degrees of an angle makesit even more precise. We also use constellations as a means of mapping and findingobjects in the night sky. Then finally the scientific coordinate system used byastronomers worldwide shows us the level of precision needed by astronomers.

Students will see benefits and limitations to each method. They will learn to usethe different methods and discover some interesting sky phenomena along the way.

1. Synopsis and Objectives

"Star Maps" will be a live show that will examine the sky as seen with both theunaided eye and with the use of a small telescope. Emphasis will cover different ways offinding both bright and obvious sky objects as well as those that are dim and hidden.

o The main objectives will be for the students to learn different methods used tofind their way around the night sky, discover sky objects, and understand whatthey are looking at.

o The types of sky objects covered will be the Sun, stars, constellations, nebulae,planets, meteors, and the Milky Way.

o Key concepts that will be discussed will include: altitude and azimuth, coordinatesystems (latitude & longitude, declination & right ascension), constellations, theSun, stars, luminosity, clusters, galaxies, diurnal motion, and sky-lore.

o Constellations change with the seasons. Constellations covered will vary with thetime of the year of our visit. Of course, others may be shown upon request.

• Year Round constellations: Ursa Major (the big bear or dipper), Ursa Minor(the small bear or dipper), Cassiopeia (the queen).

• Autumn constellations: Aquila (the eagle), Cygnus (the swan), Lyra (theharp), Andromeda (the princess), Pegasus (the flying horse).

• Winter Constellations: Orion (the hunter), Canis Major (the big dog), CanisMinor (the little dog), Taurus (the bull), Gemini (the twins).

• Spring Constellations: Leo (the lion), Bootes (the bear chaser aka the icecream cone!), Virgo (the maiden), Corvus (the crow).


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• Summer Constellations: Scorpius (the scorpion), Sagittarius (the archer akathe teapot!), Aquila (the eagle), Cygnus (the swan), Lyra (the harp), Delphinus(the dolphin).

2. Show Outline:

o Earth from space—How do we find places?• We recognize physical geographical features that are

visible—mountains, rivers, bays, seas, oceans.• We impose political boundaries which are not actually

visible. (This is similar to the way we divide the skyinto constellations that are not really visible either.)

• We use a coordinate system to precisely locate spotson Earth (latitude and longitude).

• With this knowledge, we discover hidden spots on Earth that are worth ofinvestigation. Examples used: Grand Canyon, pyramids, Cape Canaveral.

o Starfield—How do we find places?• We note prominent stars as reference points.• We use the cardinal directions (NSEW) and altitude to find a spot. We can

also make this method more precise using degree angles.• We use constellations to divide up the sky. At this point we discover several

prominent constellations of the season, as well as a couple of deep sky objectsthat can be easily discovered with knowledge of the constellations.

o Stellar Coordinates—How astronomers locate sky objects.• Students learn the sky equivalent to latitude and longitude, which are called

declination and right ascension.• We then find the path of the Sun and planets, and why certain stars are always

visible.o Galactic Map—Where are we in the galaxy?

3. Vocabulary

Altitude is the height of a star or object above the horizon, usually measured in angulardegrees.

Azimuth is the direction of a star or object. The direction can be measured in degreesmeasured eastward from north. North being 0 degrees, east 90 degrees, south 180degrees, west 270 degrees, and 360 degrees coinciding with north at 0 degrees.Oftentimes, azimuth is generalized as simply a compass point such as north, southwest,or east for examples.

Binary Stars are stars that are gravitationally bound together. They either orbit eachother, or if one is significantly more massive than the other, the smaller star orbits thelarger one. Approximately half of the stars in the night sky are binaries. They onlyappear as single stars because of their relative proximity and their immense distancesfrom us.


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Circumpolar Constellations and Stars are the constellations and stars that never set. Thenumber of circumpolar constellations you see depends on your latitude. The further northor south you travel from the equator, the more stars become circumpolar. At the equator,no stars are circumpolar. At the poles, all stars are circumpolar.

Clusters of stars are found all over the sky. There are two types of clusters. Openclusters tend to be young stars that formed from the same nebula cloud. Open clustersoften contain between 250-600 stars. Globular clusters are much larger clusters ofhundreds of thousands and sometimes millions of stars. The stars in globular clusterstend to be much older. While open clusters are found throughout the galaxy, globularclusters tend to populate the fringes of the galaxy.

Constellations are groupings of stars that form a picture, similar to a dot-to-dot picture inthe stars, using stars as the dots. There are 88 constellations in the sky; 48 have theirorigins with Greek mythology. Today they are often used as a simple and effective wayof mapping the sky.

Declination measures distances north or south of the celestial equator in the sky. Thedistances are measured in degrees. It is equivalent to projecting the latitude lines fromthe Earth directly into space.

Diurnal Motion is the apparent motion of the stars moving from east to west across thesky. This motion is caused by Earth's rotation. It is the same motion responsible for therising and setting of the Sun each day.

Galaxies are large group of stars that are gravitationally bound together in space. We arein a galaxy known as the Milky Way. The Milky Way is a spiral galaxy containingapproximately 200 billion stars with an expanse of 100,000 light years from side to side.

Latitude and Longitude locates positions upon the Earth. Latitude measures distancesnorth and south of the equator in degrees. The equator is designated as zero, the NorthPole is positive 90 degrees, and the South Pole is negative 90 degrees. Longitudemeasures degrees eastward and westward from the prime meridian at Greenwich,England, which is 0 degrees. The center of Maine is situated at approximately 45 degreesnorth latitude and 39 degrees west longitude.

Light Year—is the distance a beam of light travels in one year’s time. Light travels at300,000 kilometers per second (186,000 miles per second)! Astronomers use this unit tomeasure great distances in space. One light year equals about 9.5 trillion kilometers (5.9trillion miles). For example, the closest star to the Sun is Alpha Centauri, which is 4.3light years away.

Luminosity is the brightness of a star or object. This term can refer to the actualbrightness a star might be if the stars were all the same distance from us, in which casewe call it absolute magnitude. The stars apparent magnitude is the brightness we see in


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the sky, which can be affected by distance, absolute magnitude, or obscuring clouds ofdust and gas.

Meridian—is an imaginary line in the sky that passes from due south, directly overheadthrough the zenith, to due north. It is unique to anyone's given location. It measuresaltitude with the north and south horizon points labeled zero degrees and the zenithlabeled 90 degrees.

Meteors are often called "falling stars" or "shooting stars." These streaks of light that flyrapidly across the sky are really tiny rocks falling through the Earth's upper atmosphere.Friction and compression between rock and the air create enough heat to make the objectburn. Most meteors never reach the ground. Instead, they burn up high in theatmosphere.

Nebulae are large interstellar gas clouds. There are several types of nebulae. The socalled hydrogen II clouds are regions of star formation; often such a nebula will haveenough hydrogen gas to create several hundred stars like our Sun. Planetary Nebulae arethe remains of dead and dying stars, they actually have nothing to do with planets. Thegot the name because of their appearance in early telescopes. Supernova Remnants arethe nebular remains from super large stars that explode, blowing the originating starapart. We see the aftermath of such an event.

Right Ascension measures the equivalent of east and west in the sky. R.A. does not usedegrees as longitude does; instead it measures in hours, minutes, and seconds. As thestars slowly move westward across the sky, it takes one hour for an hour of RightAscension to pass overhead on the meridian.

Sky Lore is a term that refers to the legends, stories, and mythology behind theconstellations and stars. Almost all constellations have numerous stories that accompanythem. This term can also apply to the origin of a star's name.

Zenith is the point directly overhead. It always has an altitude of 90 degrees and is themid-point of the celestial meridian.

4. Study Questions (these questions will be answered in the planetarium)

1. What are the cardinal points?2. What are latitude and longitude used for?3. How can a map help us find places on Earth?4. Why do you need to let your eyes "get used to the dark"? What is meant by

dark adaptation?5. Name three methods for locating a specific star in the sky.6. What is Right Ascension and Declination?7. Where is Zenith?8. Why are some stars red, blue, orange, and yellow? Why do most stars appear white?


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9. Are most stars really white?10. What is a nebula? Can you find one in the sky?11. Why are some constellations seasonal?12. What do we call constellations that are visible year round?13. What is the Milky Way?14. Are the stars of Ursa Major (the Big Dipper) part of the Milky Way?15. Which star is nearly directly above the North Pole?16. How many planets can you see without a telescope? Name them.17. Which planets are only seen in the early evening or early morning but never at

midnight?18. Why do planets all move through the same general constellations of the night sky?19. Name three reasons that one star might appear brighter than another star.20. Why does the Sun appear to move through the same set of constellations as the

planets?21. Describe what a meteor is and why it lights up as it moves across the sky.22. Why do you think there are so many stories and legends associated with the stars and

constellations?23. Are there any stars that are not in constellations?24. In the course of a year, can you see all the constellations from Maine?25. Why do we measure Right Ascension in hours and minutes rather than degrees?26. How many constellations can you name? How many can you recognize in the sky?27. How can you identify a planet from a star?28. Why are some stars in clusters?29. What is the most distant object that you can see without a telescope?30. Why can you see more stars overhead than near the horizon?

5. Sky Legends

A fascinating aspect of the history of constellations is the fact they are intricately woveninto storytelling traditions from around the world. The following two stories are bothfrom North American traditional cultures:

The Legend of the Great Bear: An Iroquois Legend

Long ago there was a great hunter named Long Sash. Long Sash loved to hunt.And there was one hunting ground that he liked better than all others. He liked thispart of the forest because in this area there was a clearing on the edge of a small pond.The pond had crystal clear water. And Long Sash knew that early every morningmany animals came to this clearing to drink water. But he never killed any animals inthis place. That was strictly forbidden because the clearing was a sacred place. Tokill something there would bring great evil to the entire tribe. Yet, he still liked towatch the animals to learn what animals were in the woods that day and decide howto hunt later in the day.

On this one day Long Sash got up about two hours before Sunrise. It was a verydark night. There was no moon. He had to walk very slowly so that he wouldn't tripon a root or a rock. When he finally got close to the clearing, the Sun was just


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beginning to rise in the east. He knew that there might already be animals drinking atthe pond. Not wanting to scare anything away, he became very, very quiet. Shhhhh.And sure enough, when he got close to the clearing he could hear something upahead. He could hear lots of ……GROWLING!

When he peeked into the clearing he saw a giant bear. And the bear was growlingand drooling. But the bear had not seen Long Sash, instead he was staring across theclearing. When Long Sash followed the bear's gaze he saw a small boy sitting on alog and crying. Obviously, the bear wanted to eat the boy and Long Sash couldn't letthat happen. But he had a big problem. He couldn’t kill the bear because it wasforbidden to do so in the clearing--no matter what! He didn't know what to do.

Then all of a sudden, the bear stood up on his hind legs and started walkingtoward the boy. Long Sash knew he had to do something and do it fast. So hejumped into the clearing and grabbed the bear to stop him. But all he could grab wasthe bear's short stubby tail. Long Sash was so mad that he began spinning the bear bythe tail, around in a circle, over his head. He spun him around and around andaround. And as the bear spun out of control, what do you think happened to his shortlittle tail? Why, it stretched of course and became very long.

Long Sash threw that bear high into the sky and he became a constellation. That'show the great bear came to be in the sky. Now you know why that bear in the sky hassuch a long tail. You might also notice that he’s very skinny too, that's because henever got to eat that little boy. Besides, this is a very old story and that bear has beenup there a very long time without anything to eat.

The Boy Hunter and the Polar Bear: An Inuit Story Illustratedin the Stars

Once there was a father who had two sons. They lived at the edge ofthe sea where the father and the older boy hunted seals on the sea ice. The younger sontried hard to be like his father and big brother, but they made him feel like a little boy.His father said that he should just enjoy being a boy and his big brother always justsmiled an annoying know-it-all smile.

One night the young boy lay awake in his bed. His father and brother snored acrossthe room of their tiny cabin. How could he ever prove that he was a good hunter too?His father and brother hunted seals, but he knew that if he really wanted to impress them,he'd have to do better than hunt a seal. The most dangerous animal to hunt, and the mostimpressive to kill, was the polar bear. If he could just kill a polar bear his father andbrother would know that he was a great hunter too.

Quietly, the boy rose from bed, dressed, then took his father's best spear and creptout the door. He hooked up the three dogs to the sled and headed far out onto the sea icein search of a polar bear. He knew that the polar bears were far out on the very edge ofthe sea ice hunting seals. He drove the dogs on and on. The sea ice seemed to go onforever.

Eventually, he came to the edge of the ice. Small icebergs were floating in thewater. Far out on a point of the ice floe he spotted the shape of a chunk of ice slowlymoving about. It was no moving chunk of ice, it was a polar bear! The wind blew in off


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the ocean. What luck! That meant that the bear could not smell him. This was hischance to prove his manhood.

He told the dogs to stop and lie down. Taking his father's spear, he slowly crept outonto the ice floe to get close enough to throw the spear and kill the great beast. Finally,when he dare get no closer, with the bear staring into the water watching for a seal, theboy quickly stood tall and proud. Using all his strength, he threw the spear high into theair. When it came down, it pierced the polar bear’s white fur covered paw. The bearthen reared up onto its hind legs and looked toward the boy with fierce anger in its eyes.

Suddenly, the boy’s pride disappeared. He realized his mistake. He had onlybrought one spear. He had no other weapon. It had never occurred to him that he mightnot kill the bear with just one throw. Now he knew he was in big trouble.

Actually the bear couldn't see very well, but when the boy started to run, the bearsaw the motion and began chase. Just before the boy reached the sled the ice brokebeneath his feet. Luckily he was moving so fast he made it to the sled without falling in.The ice broke up around them. The boy, dogs and sled went floating away on one chunkof ice, the bear on another.

So there were two small icebergs floating out to sea. One had a wounded polarbear upon it who was wearily watching the nearby iceberg with a sled, three dogs and aboy upon it. The dogs were so frightened that they started digging into the ice with theirclaws. Bits of the iceberg began to brake off and the sled slipped off the edge into thewater. Then the dogs had to dig their claws into the ice and hold on so the sled wouldn'tpull them into the cold water too. The boy hid behind the dogs out of sight of the polarbear. Slowly the two icebergs with their frightened riders drifted out to sea.

When the boy's father awoke and found his son gone--along with his best spear, hisdogs and his sled--he knew where the boy went. Without the sled and dogs, the fathercould not catch up with the boy. So he built a great fire to cast light upon the sky to showhis son the way home. The man was so heartbroken at the loss of his son he vowed neverto put the fire out until his son returns home. Today, when you visit the far north youoften still see the sky aglow with the light from the father's fire. Just watch for colorfuldancing lights in the sky, which some call the aurora borealis—the northern lights, but weknow it’s the glow of the man’s fire as he still waits for his son’s return.

This story is found today illustrated in the sky within the group of stars you might callOrion. In Inuit lore, Orion was not a character, it was seen as a story in the sky. The redstar Betelgeuse represents the wounded polar bear. The three stars of Orion's beltrepresent the three dogs. The sword is the sled that has slipped off the ice and isdangling in the water. The blue star Rigel represents the boy, hiding behind the dogs tostay out of sight of the wounded bear. And, of course, the lights of the father's fire thatglow in the sky are the lights of the aurora borealis. It was also noted that the stars ofthis story slowly drift around the sky, just as an iceberg will drift about in the sea.


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Uranus Rotates: 16 hrs. 48 min. Revolves: 84 yrs. Cloud topTemp: -346°F (-210°C). Diameter: 31,600 mi. ((50,800 km.).Gravity: 0.93 X Earth’s. Composition: Mostly Hydrogen, Helium,some Ammonia, and Methane. 27 moons, about a dozen thin rings.Uranus is tipped on its side. Visited by Voyager 2 in 1986.

Neptune Rotates: 16 hrs 3 min. Revolves: 164.8 yrs. Cloudtop Temp: -364°F (-220°C). Diameter: 30,200 mi. (48,600km.). Gravity: 1.23 X Earth’s. Composition: MostlyHydrogen, Helium, some Methane and Ammonia. 13 moons,3 thin rings, 2 broad rings. Visited by Voyager 2 in 1989.

Pluto Rotates: 6 days, 9 hrs. Revolves: 248 yrs. Temp: -400°F (-238°C). Diameter: 1900 mi. (3,000 km.). Gravity: 0.03 X Earth’s.Has a very thin atmosphere. 1 moon, no rings. The moon, Charon, ishalf the size of Pluto, some scientists refer to Pluto & Charon as a“Double Planet.” Pluto’s orbit is very elliptical and tilted; it actually

crossed inside Neptune’s orbit from 1979-1999.

Quaoar & The Kuiper Belt Quaoar Diameter: 800 miles (1,290km.) and is slightly farther away from the Sun than Pluto. It is madeprimarily of ices. It is the largest known object in the Kuiper Belt(other than Pluto!). The Kuiper Belt is a band of icy objects justbeyond the orbit of Neptune; similar to the Asteroid Belt, the KuiperBelt is made of objects too small to be labeled as planets. BothQuaoar and Pluto reside within the Kuiper Belt.

Sedna Revolves: 10,500 years. Diameter: 1000 mi. (1613 km.) Sednais the most distant object yet discovered in the solar system. It wasdiscovered in 2003, it is roughly three times further away than Pluto,well outside the Kuiper Belt. Currently, scientists have not officiallyclassified it as a planet. If they do, Sedna would become the smallestplanet, the coldest planet, and the most distant planet! Sedna was named

after an Inuit Goddess of the Sea.

2003 UB 313 Announced in August 2005, this may be a new planet inour solar system! Revolves: 557 years. Its orbit is tilted 45 degrees. Itwas first photographed in October 2003, but was not detected untilJanuary 2005. This object is larger than Pluto and currently about threetimes farther away from the Sun than Pluto. It may soon be officiallyclassified as the 10th planet. It does not yet have an official name—thatwill come soon. It is made of ices, much like Pluto.


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7. True or False

1. Half of all the stars we see in the night sky are binaries. (True)

2. All the stars we see in the night sky with our eyes alone are part of the Milky Waygalaxy. (True)

3. It’s impossible to see artificial satellites in the night sky. (False)

4. Only 5 of the 9 planets in our Solar System can be seen in the night sky without atelescope. (True: Mercury, Venus, Mars, Jupiter and Saturn)

5. Open star clusters contain between 500,000 and 1,000,000 stars each. (False:Globular clusters have this many stars. Open clusters average only 200-600 stars.)

6. Night vision is obtainable after approximately 3 minutes. (False: 10 minutes is amore reasonable amount of time.)

7. Galileo invented the telescope. (False: He was the first to point it towards space,but most historians believe the inventor was Jan Lippershey of Holland.)

8. The first planet discovered with a telescope was Uranus. (True: Uranus wasdiscovered with a telescope by William Hershel in 1781. He originally named it“Georgium Sidus” for King George III of England.

9. Telescopes make objects look brighter. (True)

10. Telescopes help us see very tiny objects like germs and bacteria. (False: That’sa microscope.)

11. A pair of binoculars is simply two small telescopes attached together, one foreach eye. (True)

12. With binoculars you can see more than twice as many stars as you can see withjust your eyes. (True)

13. Polaris (the North Star) is a circumpolar constellation. (True)

14. The Diurnal Motion of the stars is caused by the rotation of the stars around thegalaxy. (False: it is caused by the rotation of the Earth.)

15. The most distant object that you can see without a telescope is the AndromedaGalaxy. (True)

16. A red star is hotter than a blue star. (False)


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17. Meteors are burning rocks orbiting the Sun. (False: the are only on fire whenfalling through a planet's atmosphere.)

18. The height of Polaris above the northern horizon measured in degrees is alwaysequal to you latitude (within a degree of accuracy). (True)

19. The constellation Orion is visible in the early evening sky throughout the monthof October. (False: Orion rises late at night in October.)

20. The "Summer Triangle" of stars is visible in the fall. (True)

8. Web Site Informationhttp://www.northern-stars.com

Northern Stars Planetarium offers an extensive web site forteachers and students to use. It offers information on planets,telescopes, meteor showers and comets. You will find star charts,bibliographies, web links to many great astronomy sites, and amonthly article covering what is visible each month.


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Planetarium Program Evaluation for Sky Maps

After the Northern Stars Planetarium has visited your class, please take a moment to fill out thisevaluation. Your suggestions are very valuable to us!

Mail the completed evaluation to :......................Northern Stars Planetarium 15 Western Ave.

Fairfield, Maine 04937Or Email To :............................................…[email protected]

1. Group grade/age level:___________________________________________________

2. Was the material presented at an appropriate level for your class? ______________________________________________________________________________________

3. Was the amount of material discussed: Enough Overwhelming Not Enough

4. Should any parts of the presentation be developed further? ______________. If so,which parts?

5. Was there sufficient time for questions and answers? Yes No

6. Were you studying astronomy or another related subject at the time of theplanetarium’s visit? Yes No

If so, was the planetarium visit helpful? _______________________________________

7. Was the Teacher’s Guide helpful in preparing your class for the planetarium visit?Yes No

Which parts were most helpful? ____________________________________________

Which parts were least helpful? ____________________________________________

8. Did the presenter present the material in a clear and understandable fashion?_____________________________________________________________________

9. How would you rate the overall program given to your class in the planetarium?_____________________________________________________________________

10. (Optional) Your name & school:_________________________________________

Thank you for your time! Your Comments Make a Difference!

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