Topic 2.1 - Our Solar System Flashcards
How many known satellites, or moons, of planets are there in our solar system?
160 and this number keeps on growing
Name all 5 dwarf planets in our solar system.
Ceres, Pluto, Haumea, Makemake and Eris
What is an asteroid?
A small (mostly less than a few hundred km in size but larger than 10 m) solid bodies, with the majority orbiting in the Asteroid or Main Belt between the orbits of Mars and Jupiter
What is the name of the brightest asteroid?
Vesta
What is a comet?
Nuclei of ice, dust and rock that develop gaseous coma and tails when relatively close to the sun
What is a centaur?
These show similarities to both asteroids and comets and are named after the mythological half-man, half-horse race of centaurs; they generally orbit the Sun between the orbits of Jupiter and Neptune and include Chiron, Hidalgo and Asbolus
What are Trans-Neptunian Objects (TNOs)?
Objects orbiting the sun beyond Neptune
Name 7 types of object that the sun is host to in our solar system?
- 8 planets
- Satellites of planets
- Dwarf planets
- Asteroids
- Comets
- Centaurs
- TNOs
What do the International Astronomical Union define a planet as?
A body that:
•Is in orbit around the sun
•Is large enough to be spherical
•Had ‘cleared its orbit’ of other objects
What is the mean distance to the sun for each planet in our solar system in AU?
Mercury - 0.38 Venus - 0.72 Earth - 1 Mars - 1.5 Jupiter - 5.2 Saturn - 9.5 Uranus - 19.1 Neptune - 30
What is the diameter of each planet in our solar system in km (rounded)?
Mercury - 4,800 Venus - 12,100 Earth - 12,800 Mars - 6,800 Jupiter - 143,000 Saturn - 121,000 Uranus - 51,000 Neptune - 50,000
Name 4 facts about Mercury
- Heavily cratered
- Contains highlands
- Lava-filled basins
- Many parts of the surface appear to be almost identical to that of the moon
Name 5 facts about Venus.
- It’s backwards spinning
- Similar to Earth in size
- Clouds of sulphuric acid
- Surface pressure 90 times greater than that on Earth
- Dense atmosphere containing Carbon Dioxide which prevents infra-red radiation from leaving Venus making the surface and lower atmosphere so hot - a ‘runaway greenhouse effect’ with a temperature of 470℃
Name 5 facts about Mars.
- Has iron-rich rocks
- Has seasonal ice caps
- A 450 km-long water-carved canyon called Valles Marineris stretching east-west across its surface
- Contains the highest volcano in the solar system - Olympus Mons
- Has violent dust storms rage across its surface
Name 3 facts about Jupiter.
- Rotates on its axis in only 10 hours
- ^Producing an equatorial bulge and causing dynamic wind that split the atmosphere into a series of red-brown belts and yellow-white zones
- Jupiters Great Red Spot is an anticyclone system larger than Earth
Name 4 facts about Uranus.
- It spins almost on its side.
- It’s almost featureless.
- The blue-green colour is a result of the amount of methane in its mostly hydrogen and helium atmosphere.
- 80% or more of its mass is made up of a fluid mix of water, methane and ammonia iced.
Name 4 facts about Neptune
- There is a great dark spot.
- Has cirrus-like clouds of frozen methane at high altitudes.
- It’s atmosphere also contains gigantic storms.
- It also has a faint system of rings.
Name the Galilean moons of Jupiter.
Io, Europa, Ganymede and Callisto
Talk about Mars’ moons
Mars has two all moons Deimos (the smaller and more distant moon) and Phobos. Both are irregular in shape, only tens of km in size and heavily-cratered. Their densities are roughly half of that of Mars, and there composition is similar to that of typical asteroids. For these reasons most astronomers believe that Deimos and Phobos are captured bodies from the Asteroid Belt.
Talk about Neptune’s moon Triton.
Triton is Neptune’s largest moon (only slightly smaller than our moon) and has a highly-inclined orbit and revolves around Neptune in the opposite sense to that in which Neptune spins. This suggests that Triton is a captured body, but because of its relatively large size and mass, astronomers believe that Triton’s collision might be as a result of a collision with Neptune or another of its moons.
Which planets have ring systems?
All 4 gas giants- Jupiter, Saturn, Uranus and Neptune
Describe ring systems.
Each ring system is divided into several distinct rings, each containing billions of individual particles of ice, rock and dust that range from a few micrometers to to several metres size
What’s the difference between Saturn and Jupiters rings?
Jupiter has very dusty, dark rings whereas Saturn’s are icy and highly reflective
How thick are ring systems?
1.5 km thick
How wide are ring systems?
Up to hundreds of km wide
Name the 2 inferior planets.
Mercury and Venus
Name the 5 exterior planets.
Mars, Jupiter, Saturn, Uranus, Neptune
Diagram of inferior planet at superior conjunction.
☀️=The Sun
🌍=The Earth
🌑=Inferior Planet
🌍 ☀️ 🌑
Diagram of inferior planet at inferior conjunction.
☀️=The Sun
🌍=The Earth
🌑=Inferior Planet
🌍 🌑 ☀️
What is occultation?
When an inferior planet is close to superior conjunction, it may disappear for a short while behind the Sun; this event is known as occultation. Generally speaking, an astronomical body is occulted when it passes behind another and is temporarily hidden from view
Diagram of superior planet at opposition.
☀️=The Sun
🌍=The Earth
🌕=Superior Planet
🌕 🌍 ☀️
Diagram of superior planet at conjunction.
☀️=The Sun
🌍=The Earth
🌕=Superior Planet
🌍 ☀️ 🌕
Where do the planets appear to move through?
The zodiac band
What’s the largest moon in our solar system?
Ganymede
What is greatest elongation?
The angle between the 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 transit?
When a smaller body passes in front of a larger body?
When is the best time to observe a superior planet and why?
At opposition because they are closest to earth offering best resolution and full illuminated so visible through the night
What are the problems of astronauts venturing further than the moon?
Space adaption syndrome
Psychological problems
Communication delays
Radiation risk
What are the problems of astronauts venturing further than the moon?
Space adaption syndrome
Psychological problems
Communication delays
Radiation risk
