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## Middle school Earth and space science - NGSS

### Course: Middle school Earth and space science - NGSS>Unit 2

Lesson 2: The moon and its motions

# Phases of the moon

A moon phase is the shape of moon's sunlit portion as seen from Earth. There are a total of eight moon phases: new, waxing crescent, first quarter, waxing gibbous, full, waning gibbous, third quarter, and waning crescent. These phases repeat every 29.5 days. Created by Khan Academy.

## Want to join the conversation?

• what would happen if we had rings on our earth
• According to Cornell’s “Ask an Astronomer”, Earth (and all of our the planets) had rings at some point. The more massive a planet is, the greater the difference in its gravitational field will be at two points the same distance apart. This difference in gravity can actually pull things like moons apart, making the rings like we see on Saturn. Because our gravity isn’t as strong as the gas giants’, it isn’t as easy for a planet like Earth to make rings or hold onto them.
• Why does the moon have a affect on the tides?
• Because the Moon has a gravitational pull, when the Moon orbits around the Earth the gravity from the Moon pulls the water on Earth causing a tide. Hope this helps you.
• what would happen if we were inside of the sun
• we would burn to death
• could earths rotation cycle ever flip and go the opposite way ?
• It is highly unlikely that Earth’s rotation cycle would ever flip and go the opposite way. The Earth rotates on its axis due to the conservation of angular momentum, which is a fundamental principle of physics. This means that once an object starts spinning, it will continue to spin at the same rate unless acted upon by an external force.

However, scientists have modeled what would happen if Earth were to spin backward (retrograde instead of prograde). They used the Max Planck Institute Earth System Model to flip the sun’s rotational path and found that reversing Earth’s spin would dramatically change familiar landscapes across multiple continents. Deserts would cover North America, arid sand dunes would replace expanses of the Amazon rainforest in South America, and lush, green landscapes would flourish from central Africa to the Middle East.
• is the moon made of cheese
• no it is not this is a myth that most people belive but is sadly not true
• What would happen if the earth had many moons
• Tides would work differently.
• Why does the moon sometimes appear yellow and sometimes appear white? Why not one color?
• it depends on the lighting the sun's light reflecting off the moon
• what would happen if we had 3 sun's?