Stars & the Sun
What is a star?
A giant ball of hot gas that produces its own light.
What is a constellation?
A pattern of stars as seen from Earth.
What is rotation?
Earth's spinning around its axis.
What causes day and night?
Earth's rotation.
What makes a star visible to us?
Light from the star reaches our eyes.
What star is closest to Earth?
The Sun.
True or False: The stars in a constellation are necessarily close together in space.
false
About how long does Earth take to complete one rotation?
about 24 hours
True or False: When your part of Earth is facing away from the Sun, it is nighttime.
True
A student sees a group of stars in the eastern sky at 8:00 p.m. Where might those stars appear later in the night?
Farther west
True or False: The Sun is a star.
True.
Why might people in different parts of Earth see different stars?
Their locations on Earth give them different views of the sky.
what is revolution (revolving, orbiting)?
Earth's movement around the Sun.
Why can't we see many stars during the daytime?
Sunlight makes the sky much brighter, making most stars difficult to see.
A student says, "The stars move across the sky because they are orbiting Earth." Is this the best explanation? Why or why not?
No. Earth's rotation causes the stars to appear to move across the sky.
Which object gives off its own light: the Moon, Earth, or Sun?
The Sun.
Why can different constellations be seen at different times of the year?
Earth's position changes as it travels around the Sun.
About how long does Earth take to make one revolution around the Sun?
About 365 days, or one year.
Why does the Sun appear to move across the sky during the day?
Earth rotates on its axis.
What evidence could a scientist collect to show that Earth's rotation affects what we see in the sky?
Observe and record the positions of stars over several hours and look for a predictable change in their positions.
Why does the Sun appear much bigger and brighter than other stars?
Because the Sun is much closer to Earth than other stars.
Why is observing the sky over many nights more useful than observing it only once?
It allows scientists to identify and study predictable patterns in the sky.
Which motion of Earth helps explain why we see different constellations during different seasons?
Earth's revolution around the Sun.
A student says, "If I can't see a star, it must not be there." What is wrong with this reasoning?
A star can still be present even if we cannot see it; bright sunlight, Earth's position, or the star being below the horizon can prevent us from seeing it.
Explain why we see different stars at different times. Use at least TWO scientific ideas in your answer.
Earth rotates, changing which part of the sky we can see during a night, and Earth revolves around the Sun, changing our view of space throughout the year.