Composed mainly of Helium and Hydrogen (along with carbon, oxygen, and iron).
What is the Sun?
100
All the objects we can observe in the sky.
What is celestial bodies?
100
Someone who knows and studies the sky.
What is an astronomer?
200
Approximately December 21 (in the Northern Hemisphere).
What is the winter solstice?
200
When none of the sunlight reflected by the Moon can reach Earth.
What is a new moon?
200
The northern hemisphere is tilted toward the Sun.
What is summer?
200
An astronomical body that orbits one or more stars and is capable of forming into a spherical shape under its own gravitational force.
What is a planet?
200
About 150 million km.
What is an astronomical unit (AU) or about the distance from the Sun to Earth?
300
A body of electrically charged gas, that emits energy from nuclear reactions in its core.
What is a star?
300
Why do we see only one side of the Moon at all times?
This is because it rotates at the same rate it revolves around Earth.
300
This is a cloud of dust and gas in space (believed by scientists to be an area of star formation).
What is a nebula?
300
Often called Earth's twin.
What is Venus?
300
This is measured from the horizon (0 degrees) to the point directly overhead (90 degrees).
What is altitude?
400
This takes 24 hours on Earth.
What is a rotation?
400
This moon phase occurs after the last quarter.
What is the waning crescent?
400
A constant flow of particles streaming out of the Sun's surface in all directions.
What is the solar wind?
400
Pluto
What is a dwarf planet?
400
Approximately March 21.
What is the spring equinox?
500
Smaller recognizable star patterns within a larger constellation.
What is an asterism?
500
This takes 27 days, 7 hours, and 43 minutes to complete.
What is one revolution of the Moon around Earth?
500
This take place in the Sun, causing a rapid release of energy.
What is nuclear reactions?
500
What is the difference between a star and a planet?
Star - body of gases that undergoes nuclear reactions and radiates energy. Planet - a body that orbits a star (or stars) and is capable of forming into a sphere with its own gravity.
500
Describe how Auroras are formed.
Particles from solar winds are trapped in Earth's magnetic field; they are swept toward the North and South Poles.