Chapter 1 & 2 Flashcards
How old is the universe?
14 billion years old.
What is an expanding universe?
The idea that space between a galaxies or clusters of galaxies is growing with time.
What is an astronomical unit?
The average distance between Earth and the sun (150 million km).
What is a light year?
The distance that light can travel in a year, which is about 9.46 trillion km.
What is a rotation?
The spinning of an object on it’s axis.
What is an orbit/revolution?
The motion of one object around another.
What is a constellation?
The region of the sky with well defined borders.
What is the brightest star?
Sirius.
What is the closest star?
Centauri.
What is the pole star?
Polaris; the star that is aligned with the earth’s axis of rotation.
What causes the seasons?
The tilt of the Earth’s axis causes sunlight to fall differently on Earth during different times of year.
When is the summer equinox?
Around June 21st.
When is the spring equinox?
Occurs around march 21st.
When is winter solstice?
Around December 21st.
When is fall equinox?
Around September 22nd.
What is a lunar eclipse?
When the Earth lies directly between the Sun and the moon, so that the earths shadow falls on the moon.
What is a solar eclipse?
When the moon lies directly between the sun and earth, so that he moons shadow falls on Earth. People living within the area covered by the moons shadow will see the sun blocked or partially blocked from view.
What phase of the Moon is this?
Waning crescent
Rise: 3 AM
Highest: 9 AM
Set: 3 PM
What phase of the moon is this?
Third Quarter
Rise: Midnight
Highest: 6 AM
Set: Noon
What phase of the moon is this?
Waning Gibbous
Rise: 9 PM
Highest: 3 AM
Set: 9 AM
What phase of the moon is this?
Full moon
Rise: 6 PM
Highest: Midnight
Set: 6 AM
What phase of the moon is this?
Waxing Gibbous
Rise: 3 PM
Higest: 9 PM
Set: 3 AM
What phase of the moon is this?
First Quarter
Rise: Noon
Highest: 6 PM
Set: Midnight
What phase of the moon is this?
Waxing Crescent
Rise: 9AM
Highest: 3 PM
Set: 9 PM
