Download Introduction to Constellations

Introduction to Constellations
Backyard Astronomy
The Night Sky
People have watched the night skies for
millions of years. Some just out of
curiosity. Some out of boredom. Some
looking for portents, either good or bad.
However, the one thing that they all saw
was that there was a pattern in the way
the stars revolved around the heavens.
The Night Sky
You need only to look up for a few hours to
begin to see these same patterns yourself.
Like the Sun, stars rise in the east and set
later in the west.
What is a star?
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A STAR is a large sphere of glowing gases.
Stars change over time.
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Which is the closest star to Earth?
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THE SUN!
The sun is a medium sized star
MUCH, MUCH larger than Earth
Star Finders
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When you first see the sun in the morning, your
spot on the earth as just started to face the sun.
As the day goes by, the spinning earth turns
past the sun. It’s highest at noon.
Star Finders
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Your last view of the sun comes at sunset. The
earth is turning you away from the sun. At night,
stars rise and set the same way the sun does in
the daytime because the earth is turning past
them too.
A pattern or
group of stars in
the sky is called
a constellation.
People of ancient
time saw the
constellations as
character or
animals in the sky.
They made up
stories to explain
how the object,
animal, or character
came into the night
sky.
Star Patterns
The Big Dipper and Other
Constellations
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The stars in the sky appear to be moving. If you look for
constellations, you will find that they are in different
positions at different times in the night.
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If you look closely, you will notice that the stars appear
to move around a central star. We call this star the
North Star or Polaris.
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However, it is not the stars that are moving. We are!!!
The earth is rotating. Therefore, the stars in the sky look
like they are moving to us.
Finding Polaris and Why
Polaris (or the North Star) is where you
want to start.
Because Polaris is aligned with the Earth’s
axis of rotation, it remains fixed, with all the
other planets and stars appearing to move
around it. It is the one star that remains
fixed at all times.
Why Can We Always See the North
Star?

The North Star is located almost directly
above the North Pole. The earth’s axis
points towards it.
Stars as Tools for Navigation
 The North Star is called Polaris and located directly
above the North Pole. This star appears in the same place
every night all year long.
 In the Northern Hemisphere, if you find Polaris you
will be able to tell which direction is north.
The Southern Hemisphere does not have a star to help
you find its pole. In stead it has what is known as a
Southern Cross.
 The Southern Cross consists of 4 bright stars and
some dimmer ones. All of these together point to the
south pole.
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Why Do We See Different Constellations
in the Sky?
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As the earth moves in its orbit around the sun,
the stars which we see are different.
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Constellations we see change with the seasons
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Also, as the earth rotates on its axis, the stars
which we see are different. The sky at 7pm
looks different than the sky at 10pm.
Finally, people look at the sky from different
locations on the earth see different stars.
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One Way to Find Polaris
Find the Big Dipper: The two stars that
form the front of the cup of the dipper
define a line pointing to Polaris.
The Big Dipper
The Great Bear
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Movement of the Big Dipper over
the Course of a year
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The Stars Circling Polaris
Lets try a demonstration to show
the movement.
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1. I need a volunteer to be earth
2. Everyone else is going to be a star!
We need a circle with all the stars on the
outside and the earth in the middle.
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Brainpops
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Constellations
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Telescopes
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Constellation Songs:
https://www.youtube.com/watch?v=GzaMw
oo9Ue0
How to find Constellations
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Now That You’re Oriented, It’s Time
to Explore.
You’re pointed in the right direction, but what now.
Stars and constellations move constantly and
seasonally. What am I looking for? What you need is a
star map.
STAR CHARTS
How can we identify constellations in the
night sky?
The use of a star chart can help us!
A STAR CHART is a map of the stars in
the night sky.
STAR CHARTS
On a star chart, lines often connect the
stars that might make up a constellation.
Different star charts must be used at
different times of the year and in different
places on Earth.
Many stars visible from the Southern
hemisphere cannot be seen from the
Northern hemisphere.
STAR CHARTS
Lets Make One!
http://www.skyandtelescope.com/a
stronomy-resources/video-usingstar-charts-and-star-wheels/
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Specific stars are visible
depending upon:
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· from where on the planet Earth you view
the sky.
· the position of the Earth in its yearly
journey around the Sun.
· stars on the opposite side of the Sun are
not visible from the Earth.
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What other tools can help us identify
constellations?
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STAR CHARTS are the BEST for
identifying a constellation in the sky.
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A COMPASS is the BEST for locating
DIRECTION (North, South, East, and
West) You need to know direction before
you can use a star chart correctly.
What other invention helps us view
items in space?
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A telescope!
NOTES:
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Star- large __________ of glowing
_________
Constellations- a _________ or group of
______ in the sky
Star Chart- _______ of the ______ in the
night sky
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used as a way to identify constellations
Compass- used to locate _________ in
order to use a star chart _________
Telescope- used to see ______ away
________ in ________ up-close
NOTES:
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Star- large sphere of glowing gases
Constellations- a pattern or group of stars in
the sky
Star Chart- map of the stars in the night sky
used as a way to identify constellations
Compass- used to locate direction in order
to use a star chart correctly
Telescope- used to see far away objects in
space up-close
Other Cool Things
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As seen from the Earth, the sun appears
projected against the fixed background
stars. As the Earth revolves around the Sun
during the year, the sun will appear to
move through the stars, making one
complete circuit of the sky in 365 days.
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The stars through which the sun moves are
located along the Ecliptic and comprise the
12 constellations of the Zodiac.
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The sun spends about one month in each
sign of the zodiac.
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The stars opposite the sun make up our
night sky. Because of the Earth’s revolution
around the sun, the night sky constantly
changes as well.
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With each season having its distinctive
grouping of constellations. The stars that
are in the daytime sky or winter, for
example, will be the nighttime stars of
summer.
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A Few Constellations...
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Circumpolar Constellations
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- Ursa Major – The Big Bear - This is the
constellation that houses the ever famous
Big Dipper!
- Ursa Minor – The Little Bear
- Cassiopeia – The Queen of Ethiopia
- Cepheus – The King of Ethiopia
- Draco – The Dragon
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Ursa Minor
Once you’ve located Polaris, you’re ready
to identify your first constellation. Polaris
is the last star located in the handle of the
asterism, the Little Dipper. The name of
the constellation that contains the Little
Dipper is Ursa Minor or Little Bear.
Ursa Minor
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Ursa Minor, also called the Little Dipper, is a
circumpolar constellation. This means it never
sets in the northern sky. The true figure
represented by the stars is the Little Bear.
There are several mythological stories behind
these famous constellations. In Greek myth, Zeus
was having an affair with the lovely Callisto.
When his wife, Hera, found out she changed
Callisto into a bear. Zeus put the bear in the sky
along with the Little Bear, which is Callisto's son,
Arcas.
Ursa Minor
Ursa Major
Ursa Major is probably the most famous constellation, with
the exception of Orion. Also known as the Great Bear, it has
a companion called Ursa Minor, or Little Bear. Everyone
living in the Northern Hemisphere has probably spotted the
easily recognized portion of this huge constellation. The body
and tail of the bear make up what is known as the Big
Dipper.
Several different cultures saw a big bear in the sky. The
ancient Greeks had a few different stories to explain how the
animal ended up there. In one story, Hera discovered Zeus
was having an affair with Callisto and turned her into a bear.
Zeus put her in the sky along with her son, Arcas, who
became the Little Bear.
Ursa Major
Draco
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Draco the dragon, is only present in the Northern
Hemisphere, so those living in the Southern Hemisphere will
never see this long constellation.
The easiest way to spot Draco is by finding his head. It
consists of four stars in a trapezoid, burning brightly just
north of Hercules. From there, the tail slithers through the
sky, eventually ending between the Big and Little Dippers. It
can be difficult to trace Draco in the night sky. From the
head, follow the body north towards Cepheus. It suddenly
shifts south and west, ending up between the two dippers.
The end of the constellation is held by Thuban, which was
the pole star over 4,000 years ago.
Draco
Orion’s Belt
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The constellation Orion is in the south.
Look for the three bright stars in a row that
make up Orion’s belt.
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