There are ___ planets in our solar system
8
a big collection of gas dust and billion of stars
Galaxy
structure includes all matter and space that exists
The universe
When the earth sees the side of the moon that is fully lit up
full moon
This imaginary line goes from the North Pole to the South Pole
Its gravitational force holds our solar system together
The Sun
Our galaxy is this type of galaxy
Spiral
This is a star system with two stars
Binary Stars
When the moon is becoming brighter during the moon cycle, it is said to be:
Waxing
This is the spinning of a planet or other object, Earth's takes 24 hours
Rotation
This is the hottest planet in our solar system
Venus
This type of galaxy is made up of older stars, and lacks any space dust or gases
elliptical galaxy
a star and its planets is called a
star system
When the earth casts its shadow on the moon
Lunar Eclipse
This is the term for a single orbit of a planet or moon. Earth's takes 365 days
Revolution
In order for a celestial object to be considered a planet it must:
Have cleared its orbital path around the star it revolves, Be spherical due to its gravity and orbit a star
This is a younger galaxy with a large black hole in the center that emits intense radiation
Quasar
This is a group of stars that are close together
Star Cluster
This is how long the lunar cycle lasts
29-30 days
The earth is furthest from the sun during this season
summer
Our Solar System is ___ years old
4.6 billions years old
The Milky Way galaxy will be colliding with this galaxy in about 5 billion years
Andromeda
The theory that the universe inflated rapidly from an infinitely small, dense spot and the most accepted scientific explanation for the creation of the universe
The big bang
The moon only eclipses the earth during this phase of the lunar cycle
new moon
Why does earth experience seasons?
Earths axial tilt causes the northern hemisphere to get more daylight in the summer, and less daylight in the winter