Solar system and orbits Flashcards
What are the eight planets in the solar system in size order? (smallest first)
Mercury, Mars, Venus, Earth, Neptune, Uranus, Saturn, Jupiter
What are the eight planets in the solar system starting with the closest to the sun?
Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune
What are the three requirements for something to be a planet?
A planet has to orbit a star, be massive enough to be rounded by its gravity, and have cleared its orbit of other debris (with gravity)
What is a dwarf planet?
A dwarf planet is a plant-like object, but has not cleared its orbit fully of debris.
What is an example of a dwarf planet in our solar system?
Pluto
What are the four inner planets?
Mercury, Venus, Earth, Mars
What are the properties of the four inner planets?
They are relatively small and made of rock.
What are the four outer planets?
Jupiter, Saturn, Uranus, Neptune
What are the properties of the four outer planets?
They are large and made up of gas, making them gas giants.
What is a moon?
A moon is a natural satellite of a planet or dwarf planet.
What galaxy do we belong to?
Our solar system belongs to the milky way galaxy.
How many stars are in the milky way? (approximately)
Billions
How are the stars in the Milky Way held together?
The stars in the Milky Way are held together by gravity
What is a satellite?
A satellite is an object that orbits a second, more massive object.
What is an orbit?
An orbit is the curved path an object follows around a star, planet, or moon due to gravity.
What provides the force that create orbits?
Gravity provides the force that creates orbits.
How do the planets move around the sun?
The planets move around there sun in almost circular orbits.
What forces change and don’t change in an orbit?
An object in an orbit is constantly changing velocity but not speed, this means it is accelerating.
What is the difference between velocity and speed?
Speed measures how fast something is moving, velocity measures the speed and direction of something moving.
What is centripetal force?
Centripetal force is the force that pulls an object toward the centre of its circular path.
What is the centripetal force for our planets?
Gravity is the centripetal force of our planets, meaning it pulls the planets to the sun and keeps it in its orbit.
What is always at a right angle in an orbit?
In an orbit, the velocity is always at a right angle to the centripetal force (gravity).
What happens if the speed of an object in an orbit is wrong?
If the speed of an object in an orbit is wrong, it will either fly out of its orbit or crash into the object its orbiting.
How does the size of an orbit depend on the objects speed?
The smaller the orbit, the faster the speed.
Why does the size of an orbit depend on the objects speed?
The stronger the force (gravity), the faster the orbiting object needs to travel to remain in orbit and not crash.
What is an artificial satellite?
An artificial satellite is a man-made object that orbits around Earth or another planet.
What is the use of an artificial satellite?
An artificial satellite is used for communication, weather forecasting, navigation, and scientific research.
What type of wave does an artificial satellite use to communicate?
Artificial satellites typically use radio waves to communicate.
