Space Flashcards
What is a moon?
A natural satellite that orbits any object (mostly planets) other than a star
How many hours does it take the earth to rotate?
24 hours
How long does it take the earth to orbit the sun
1 year / 365.25 days
What type of orbit do the planet and the moon perform?
Elliptical
What was the first model of the solar system called?
Aristotle’s Model (2300 years ago)
What was the second solar system model called?
Ptolemy’s Model (2000 years ago)
What was the third solar system model?
Copernicus Model (500 years ago)
He was the first person to put the sun at the centre of the solar system instead of the earth
What is the most modern solar system model called?
Kepler’s Model
What is the definition of a planet?
A celestial body moving in an elliptical orbit round a star
What is the definition of a comet?
A celestial object consisting of a nucleus of ice and dust and, when near the sun, a tail of gas and dust point away from the sun.
What is the definition of an asteroid?
A small rocky body orbiting the sun. Mostly found in the asteroid belt.
What is mass measured in?
Kilograms
What is weight measured in?
Newtons
What is the word equation for weight?
Weight = Mass x Gravitational field strength
It’s summer in the UK. Is the North Pole tilted towards or away from the sun?
Towards
It is summer. Will the days be long or short?
Long
It is summer. Will the sun be low or high in the sky?
High
It is winter in South Africa. Will the sun feel very warm?
No
Why will the sun not feel very warm?
Its rays are more spread out
How long does it take the moon to orbit the earth?
28 days
How long does it take the moon to rotate on its axis once?
28 days
How long does it take for the phases to restart?
1 month
What are the four phases called?
First quarter, full moon, last quarter, New moon
When does a lunar eclipse occur?
When the moon is in the earth’s shadow
What is the definition of an eclipse?
The movement of one solar system object into the path of another.
What is a solar eclipse?
The moon blocks the light from the sun, meaning that a small part of earth is in the moons shadow
What is a lunar eclipse?
The earth’s shadow completely or partially covers the moon.
Why does the moon turn red during a lunar eclipse?
The red wavelengths around our planet are being bent by our atmosphere and hit the moon, making it appear red
What is a galaxy?
A system of millions or billions of stars, together with gas and dust, held together by gravitational attraction.
What is our home galaxy called?
Milky Way
Why do we use light years?
We use them to measure something that is too big to measure in metres or kilometres
How wide is our galaxy?
105,700 light years across
How thick is our galaxy?
1000 light years
What is the closest star to the sun?
Proxima Centauri
How long would it take humans to travel to Proxima Centauri?
Over 70,000 years (4.3 light years)
