2.1 Our Solar System Flashcards
What are the gas giants?
Jupiter
Saturn
Uranus
Neptune
What are the terrestrial planets
Mercury
Venus
Earth
Mars
What is the sun the host to?
8 planets, over 160 moons, satellites, dwarf planets, asteroids
Name some dwarf planets
Ceres
Pluto
Eris
Makemake
What is an asteroid
Minor planets, small mostly less than a few hundred km but must be larger than 10m and are solid, the majority orbit the main belt between the orbits of Mars and Jupiter
Must be orbiting the sun too
What’s a comet
A relatively small nuclei of ice, dust and rock, at times active, object whose ices can vaporize in sunlight forming an atmosphere (coma) of dust and gas and, sometimes, a tail of dust and/or gas when close to the sun very elliptical orbit
What’s a centaur
Half asteroid half comet, generally orbit between Jupiter and Neptune
What’s a trans-Neptune object (TNO)
An object orbiting the sun beyond Neptune
How do we classify if an object could be a planet
Is on orbit around the sun
Is large enough to spherical
Has cleared its orbit of other objects
Name some features and describe Mercury
Mercury is Heavily cratered
Mercury has highlands
Mercury has lava filled basins
Average temp 170 degrees c
Rotation period: 59 days
Name and describe Venus
Venus is similar to earth size
Venus is backwards spinning (retrograde)
Venus has a surface temperature of 470 degrees
Venus has Dense atmosphere containing carbon dioxide - prevents IR radiation leaving so surface and atmosphere heat up
Venus has Clouds of sulphuric acid
Rotation period: 243
What’s Mars like?
Mars has iron rich rocks
Mars has seasonal ice caps
Mars has a carved canyon that’s water and 450km long stretching east to west across surface
Mars has highest volcano in solar system - Olympus mons and causes violent dust storms
Temperature : -50 degrees
Rotation period: 1 day
What’s Jupiter like?
Jupiter spins on axis in 10 hours so it has a equatorial bulge causing the atmosphere to split into a series of red-brown belts, yellow-whit zones
Jupiters Great Red Spot is a anticyclone weather system that has been happening for 350 years
Average temperature: -150 degrees c
What’s retrograde motion?
Planets appear to do a loop the loop because planets orbit the sun at different speeds - both angular and actsully with the speed decreasing distance as the distance from the sun increases, we see planets from different view points sometimes overtaking and undertaking planets making them appear to move backwards
What’s Saturn like?
No long term features
Saturn has rings built up of dust and rock
Rotation period 0.43 days
Temperature: -180
What’s Uranus like
Made up of hydrogen, helium, methane and ammonia
Spins on its side
Surface is featureless
Rotation period 0.72 days
Temperature -210
What’s Neptune like
Many surface markings
- great dark spot
Cirrus like clouds of frozen methane
Rotation period 0.67 days
Temperature; -220
What are the problems of astronauts venturing further than the moon
Space adoption syndrome, may become disorientated and suffer from poor concentration
Zero gravity environment can cause brittle bones, muscle fatigue, reduced red blood cells
Communication delays - radio signals travel at the speed of light
Radiation risk - subject to ionising radiation from sun, solar radiation can increase risk of cancer
Life expectancy
What are Mars moons
Deimos and Phobos
Name some charecreristics of Deimos
Smaller, more distant, irregular shape, Heavily cratered, density roughly half of Mars
Astronomers believe it’s captured from asteroid belt
Name some characteristics of Phobos
Irregeluar shape, heavily cratered, density half of Mars, composition similar to asteroids
Astronomers think it originates fro asteroid belt
What’s the largest moon in Neptune
Triton - neptunes moon
Name some features of Triton
Orbits Neptune
High incline orbit
Revolves around Neptune opposites way to way Neptune spins - suggest triton is a captured body but Becuase if size could be a result of a collision of Neptune or another of neptunes moons
What’s the second largest moon in Neptune
Dark proteus, neptunes moon
What’s the largest moon
Ganymede - bigger than Mercury
Diameter - 5300km
Name some features of nereid
360 days orbital period to Neptune
Most likely a captured Kuiper Belt Object
Which planets have rings
All four gas giants - Jupiter Saturn Uranus Neptune ABOVE THERE EQAUTORS
What are ring systems like
Each system divided into several distinct rings, each contagion ONG billions of individual particles of ice rock and dust that range from a few micrometres to several metres in size
How wide can ring systems be
Up to hundreds of thousands of KM
How thick can a ring system be
1.5km thick
What is the origins of rings
They are uncertain - possible they formed from debris left over of formation of the planet or large impacts between moons
Or a moon that was torn apart through tidal gravitational forces
Or material ejected from surfaces of moons by meteor impacts
What shape do the planets orbit in
Ellipses
Where do the planets appear to move through
The zodiac Band
What are the inferior planets
Mercury and Venus
What are the superior planets
Mars to Neptune
What is greatest elongation
The angle between s sun and a planet with earth as its reference point - Mercury and Venus have 90 degree angle between earth and sun
What’s the best position to observe an inferior planet
Greatest elongation
What’s inferior conjunction
a conjunction of Mercury or Venus with the sun, in which the planet and the earth are on the same side of the sun.
What’s superior conjunction
a conjunction of Mercury or Venus with the sun, when the planet and the earth are on opposite sides of the sun.
When Mercury and Venus are behind the sun
What’s transit
When a smaller body passes in front of a larger body
What’s occultation
When an object moves behind another and is hidden
When is the best time to observe a superior planet and why
At opposition Becuase they are closest to earth offering best resolution and full illuminated so visible through the night
What’s opposition
When 2 celestial bodies are in opposite ends of sky eg a lunar eclipse
What is the order of dwarf planets from sun
Closest Ceres Pluto Haumea Makemake Eris Furthest
