The Stars and the Solar System

1
The Stars and the Solar System

• What do you know about the solar system?

2
Georgia Performance Standards

• S4E1 Students will compare and contrast the
  physical attributes of stars, star patterns, and
  planets.
• Recognize the physical attributes of stars in the
  night sky such as number, size, color, and
  patterns.
• Compare the similarities and differences of
  planets to the stars in appearance, position, and
  number in the night sky.
• Explain why the pattern of stars in a
  constellation stays the same, but a planet can be
  seen in different locations at different times.
• Identify how technology is used to observe
  distant objects in the sky.

3
Essential Questions

• What is a star?
• How are stars alike and different from each
  other?
• How does the sun compare to other stars in the
  night sky?
• How are constellations alike and different?
• Why are some constellations observed during some
  seasons, but not during other seasons?
• How can technology be used to observe distant
  objects in the sky?

4
STARS

• A star is a huge ball of hot gases.
• When seen from the Earth, most stars appear as
  small points of light because they are very far
  away.
• They form fixed patterns that change position in
  the sky as Earth rotates and revolves.

5
A star as seen from Earth.
6
Star

• A STAR is a ball of hot gases that gives off
  light and other forms of energy.
• Stars have different sizes. White dwarf stars are
  about the size of Earth.
• Supergiant stars can be wider than 300 million
  miles. That is more than one thousand times the
  distance from Earth to the Moon.

7

• Dwarf star
• 
  Supergiant Star

8
How many stars are there?

• On the clearest night, you can see hundreds of
  stars.
• The universe holds many, many more stars than you
  can see from Earth.
• These stars are too far away to be seen with the
  unaided eye.

9
The Sun

• The SUN is a star.
• It is the largest object in the solar system.
• More than 1 million Earths would fit inside the
  sun.
• The sun is a medium sized star.
• It looks much larger than the stars you see at
  night because it is so much closer to the Earth.

10
Sun
11
Sun

• Living things on Earth depend on the Sun for heat
  and light.
• The Sun also emits energy in forms that would
  harm life. Fortunately, gases in the Earths
  atmosphere protect the surface from much of this
  energy.

12
Constellations

• A constellation is a group of stars that forms a
  pattern shaped like an animal, person, or object.
  
• Scientist recognize 88 constellations.

13
Constellations seen in the night sky
14
Great Bear Constellation
The Big Dipper
15

• Stars are always present, even during the day.
• You just cannot see them during the day because
  the sky is so bright.
• Each night the stars appear to move across the
  sky. This is caused by the rotation of the Earth.

16
Constellations

• As Earth rotates on its axis, the stars appear to
  rotate in the sky.
• Thus, the constellations change position in the
  night sky during the night.
• Different constellations become visible with the
  different seasons but the shape of the
  constellations DO NOT change.

17
Why do the stars in constellations stay in fixed
patterns?

• Stars are trillions of kilometers away, far
  outside the solar system.
• Even as the Earth moves through its orbit around
  the Sun, each star remains nearly the same
  distance away.

18
Seasonal Constellations

• Some constellations can only be seen on a summer
  night. Others can only be seen on a winter night.
• This is because the Earth revolves around the
  sun. As it does, the part of the night sky that
  is visible from any one place changes.

19
How were constellations used long ago?

• People depended on the constellations in many
  ways.
• Sailors studied them to find their way at night.
• Farmers used them to mark the seasons and signal
  when to plant or harvest their crops.

20
Northern Hemisphere

• Summer constellations
  Winter Constellations

21
Solar System

• The Solar System is made up of the Sun, orbiting
  planets, their moons, and other objects traveling
  around the Sun.
• The Sun is the nearest star to the Earth.

22
Planet

• A PLANET is a large body or rock or gas in space
  that moves around a star.
• A planet DOES NOT produce light of its own. That
  is why planets almost never twinkle, while stars
  do twinkle.
• You can see planets in the night sky because of
  the Suns light reflecting, or bouncing off, of
  them.

23
Solar System

• Earth is one of the eight planets that orbit the
  sun. (Pluto is now called a dwarf planet.)

24
MOON

• You can also see Earths moon in the night sky.
• A MOON is a small, rounded body in orbit around a
  planet.
• A moon does not produce its own light. It
  reflects light from the sun. Most planets have at
  least one moon.

25
Moon as seen from Earth.
26
Earths Year

• The farther a planet is from the Sun, the longer
  it takes to orbit. The time it takes to complete
  one trip around the Sun is called a YEAR.
• Earths year is about 365 days long. Mercury
  makes a complete orbit in just 88 days. Neptune
  takes about 165 Earth years to complete its orbit
  around the Sun.

27
Sun, Moon, and Sky

• For thousands of years, people have been
  observing the Sun, the Moon, and other objects in
  the sky.
• Scientists did not learn how these objects move
  until a few hundred years ago.
• Why do you think they took so long?

28
TELESCOPES

• A TELESCOPE is a tool that makes distant objects
  appear larger, brighter, and sharper.
• Telescopes help scientists study stars, the Moon,
  and the planets.
• Scientists have used telescopes to discover that
  stars have regular patterns and planets move
  among the stars.

29
Never Look at the Sun

• NEVER look straight at the Sun, especially with a
  telescope. Doing so can DAMAGE your eyes.
• It is SAFE to look at other stars, which are more
  distant.

30
OPTICAL TELESCOPE

• This telescope magnifies (or makes an object
  appear larger) by collecting light.

31
OPTICAL TELESCOPE

• Hubble Space Telescope

32
Hubble Space Telescope

• It is different from other telescopes because it
  is in space.
• It moves around the Earth every 97 minutes.
• It was launched into space in 1990.
• It is the size of a school bus.
• It takes photographs of space from beyond Earths
  atmosphere.

33
RADIO TELESCOPE

• This type of telescope collects radio waves
  instead of light.
• Computers use the radio waves to make pictures of
  space.
• As more powerful telescopes are invented,
  scientists learn more about objects in space.

34
RADIO TELESCOPE
35
Essential Questions

• What is a star?
• How are stars alike and different from each
  other?
• How does the Sun compare to other stars in the
  night sky?
• How are constellations alike and different?
• Why are some constellations observed during some
  seasons, but not during other seasons?
• How can technology be used to observe distant
  objects in the sky?