Solar system Flashcards
What planets are Gas giants?
Jupiter, Saturn, Uranus, Neptune
What are the terrestrial planets?
mercury, Venus, Earth, Mars
What is an AU?
Astronomical unit, average distance from the Earth to the Sun (150 000 000 km)
Where is the asteroid belt found?
Between Mars and Jupiter. Jupiter’s gravity disrupts the rocks orbit every time they pass stopping them forming a planet.
What is Eccentricity?
How stretched the Ellipse is.
What type of orbit do comets have?
Very Eccentric Elliptical orbits.
What is the part of a comet that surrounds the nucleus called?
Coma.
Which tail points to where the comet has come from?
Dust tail.
What direction does the Ion tail point?
Away from the sun.
How do you work out the eccentricity of a comet?
E= 1- (b^2/ a^2)
b is the radius of the vertical axis, a is the radius of the horizontal axis, The measurements have to be in AU.
Where do long period comets come from?
The Oort Cloud.
Where do Short period comets come from?
The Kuiper Belt.
What is a) more than one meteoroid b) a meteorite c) A lump of rock in space d) a Micrometeorite.
a) Meteor
b) A meteoroid when it is on Earth
c) Meteoroid
d) A mini Meteoriod also known as space dust
What is a meteor shower?
When the Earth moves into a meteor. They happen at the same time every year so the meteor shower is named after the constellation its in front of e.g. Perseid, August.
What are dwarf planets?
Small planets whih do not have a clear path in its orbit e.g Pluto, Eris, Ceres, Makemake.
What are centaurs?
size of asteroids but make-up of comets. found between Jupiter and Neptune, come from Kuiper belt.
What are TNO’s?
Trans-Neptunian- Objects e.g Pluto and 1 200 others.
What is the Kuiper belt?
Outer solar system, lots of small bodies made up of ice.
What is direct motion?
Movement of a celestial body from east to west across the sky (as seen from Earth.)
What is the Oort cloud?
Outer most reaches of the solar system.
What is the motion of an astronomical object across the sky in the opposite direction of the rotation of the sun known as?
retrograde motion.
What is stationary point?
A point in an apparent path of a planet when it reverses its direction.
What is it called when 2 major celestial bodies can be seen in two different directions in the sky?
Opposition.
What is conjunction?
2 celestial bodies appear to be close.
What is a PHO?
A potentially hazardous object, e.g. meteor, comet asteroid.
how do you work out someone’s weight?
Mass (Kg) x Gravity (N/Kg)
What do all objects have?
Gravity, but different size bodies have different amounts.
What is the inverse square law?
surface weight / distance squared
What did Kepler discover? (3)
That all objects had an elliptical orbit.
What is Brahe do? (1)
Built new instruments for observations and noticed orbital anomalies.
What did Copernicus find out? (4)
That the sun was the centre of the Solar System.
what did Galieo see? (2)
4 jupiter moon: Io, Callisto, Europa, Ganymede. He also made a new telescope.