JUPITER CH.11 ASTRONOMY
WHAT is the surface of Europa like?
- (geologically young) surface is water ice, possibly with liquid water below •Only Earth has liquid water on or near surface •Tidal forces stress and crack ice; cracks and ridges flow (like lava flow)
Jupiter's magnetic field
- 10 times stronger than earth due to the liquid metallic region - leads to aurora like earth *Jupiter is surrounded by belts of charged particles, much like the Van Allen belts but vastly larger.*
•Great Red Spot has existed for at least ________ years, possibly much longer •____________ and energy source still not understood
- 300 years - color and energy
WHAT are the four largest moons of Jupiter called and who originally observed them?
- Galileo and that's why they're also called the Galilean moons - Io, Europa, Ganymede, Callisto
WHAT are the Galilean moons from largest to smallest?
- Ganymede - Callisto - Io - Europa
IO
- closest moon to Jupiter - Similar in size to the Moon (0.2 % of Moon) - Orange color: sulfur compounds from volcanoes in the ejecta
WHAT is the internal structure of Jupiter like?
- icy rock central core - metallic hydrogen around core - molecular hydrogen around all of it
INTERNAL STRUCTURE of Europa
- iron core - rocky mantle - possible water - icy crust
WHAT is an indication that a planet has a young or old surface?
- young surface= smoother, little to no craters - older surface= bumpy, lots of craters
JUPITER HAS the _______________ rotation rate of all planets-causing rotational ____________________.
-FASTEST -ROTATIONAL FLATTENING
WHAT is the order of the four Galilean moons from closest to farthest from Jupiter?
-Io *closest* -Europa -Ganymede -Callisto *farthest*
Comet Shoemaker-Levy 9
-a comet that broke apart July 1994 & collided with Jupiter, -providing the 1st direct observation of an extraterrestrial collision of SS objects *made everyone realize that something could hit a planet*
WHAT is Jupiter's rotation rate like?
-fastest of all planets -another reason of high magnetic field
HOW many rings does Jupiter have?
1 small ring
How big is Jupiter's magnetosphere?
30 million km across *can extend beyond the orbit of Saturn*
THE RADIUS of Jupiter is.....
71,500 km - largest of planets (112 times Earth's)
HOW many moons does Jupiter have?
79 *most of any planet*
AN IRON CORE IS sometimes a sign of....
A MAGNETIC FIELD
MAIN TAKEAWAYS about Io
Active volcanoes, due to tidal forces
___________ are seen on Jupiter just as they are on Earth
Aurora
WHAT are the major features of Jupiter?
Bands of clouds (storm); Great Red Spot
Lowest cloud layer can/cannot be seen by optical telescopes
CANNOT
Europa has few __________________.
CRATERS
WHAT happened on July 1994 regarding planet Jupiter?
Comet Shoemaker-Levy 9 hit Jupiter - in fragments, struck Jupiter, providing valuable information about cometary impacts *no one is safe from a possible comet hitting*
MAIN TAKEAWAYS about Europa
Cracked, icy surface; may be liquid water underneath
THIS GALILEAN moon has the best prospects for life. Why?
EUROPA - b/c of the amount of water
MAIN TAKEAWAYS about Callisto
Ganymede twin; rock and ice
ALL JOVIANS have mostly ____________ and ____________ in their atmosphere b/c of how big they are
HYDROGEN AND HELIUM
_____________ _______________strength is 20,000 times that of Earth
INTRINSIC FIELD
WHAT is the densest of Jupiter's moons?
IO
______ is very close to Jupiter and also experiences gravitational forces from Europa. The tidal forces are huge and provide the energy for the ___________________. (tidal tug of war causes friction)
IO - volcanoes
Most geologically active object in the solar system
IO •Many active volcanoes, some quite large
JUPITER is/is not still radiating energy from original formation
IS
ARE JOVIAN planets farther away from one another than the terrestrials?
YES
DO all Jovians have faster rotation rates than the terrestrials?
YES
DO all Jovians have rings?
YES
IS Jupiter the first Jovian?
YES
CAN you have volcanoes without plate tectonics?
YES - can be caused by tidal forces (like pumping heat)
ARE the Galilean moons tidally locked?
YES - show same face to Jupiter - similar to the Moon (luna)
JUPITER
Zeus - largest planet in the S.S.
HOW do auroras form?
anything with a magnetic field+ disturbance in atmosphere= aurora
WHY is Callisto Ganymede's twin?
b/c it's similar in size but it's a bit smaller
WHY IS JUPITER flattened?
b/c of the really fast rotation rates and centripetal force
VALHALLA
due to impact of something on Jupiter and frozen before it could disperse
WHAT is the magnetic field of Jupiter like?
highest of all planets (14 times the Earth (surface))
Galilean moons have similarities to.....
terrestrial planets
DOES the composition of Jupiter's atmosphere account for the color?
the elements cannot account for color; probably due to complex chemical interactions
MAGNETOSPHERE
the magnetic field of a planet
WHAT is the internal structure of Callisto like?
•Internal structure difference - icy-rock mixture throughout
WHAT is the internal structure of Ganymede like?
•Iron core - gives small magnetic field (1% of Earth - like Mercury) •Rocky mantle •Thought to have layers of liquid water beneath icy surface - icy crust
WHAT is the interior of IO composed of?
•Iron core - magnetic field 1/40th of Earth - too small •Rocky mantle - similar to Ganymede
JUPITER CENTRAL CORE
•ice and rock •10,000 km thick - 2 times size of Earth •Highest density of planet
WHAT is Jupiter's orbital period?
12 years
WHICH DIRECTION does most solar wind blow?
AWAY
First moon discovered to have magnetic field (1996)
GANYMEDE
THIS moon has had early plate tectonics - stopped 3 billion years ago - shown by grooves and ridges
GANYMEDE
WHAT is the albedo of Jupiter like?
It has the 2nd highest albedo
JUPITER HAS THE ______________ magnetic field - due to rotation and metallic (conductive) H interior
LARGEST
Observations of these moons give info about Jupiter's.....
MASS
WHAT part of internal Jupiter is a good conductor?
METALLIC HYDROGEN
WHAT is unique about Jupiter's mass?
Mass: 1.9 × 1027 kg (twice as much as all other planets put together)
JUPITER has ________________ and ______________ lights
NORTHERN AND SOUTHERN LIGHTS
SINCE Jupiter is does not have a solid surface... where do they measure the troposphere at?
No solid surface; take top of troposphere to be at 0 km
____________ ________________________ can weaken a magnetic field.
SALT WATER
Jupiter has been found to have a ____________, ________ ring
SMALL AND THIN RING Discovered in 1979 Lies 50,000 km from cloud tops Tens of km thick
Great Red Spot is a very ___________ storm
STABLE
EUROPA
Smallest of Galilean Moons •Weak magnetic field - small core and conductive liquid (salt water) 100 km deep •Ocean under icy crust (62 miles deep ocean)
GANYMEDE
largest moon in the solar system and Jupiter's largest moon - Has dark and light regions *larger than the planet Mercury*
MAIN TAKEAWAYS about Ganymede
largest moon; only moon with magnetic field
All planets with appreciable ___________ ___________ have Aurora
magnetic field
EJECTA
material that is forced or thrown out, especially as a result of volcanic eruption, meteoritic impact, or stellar explosion.
JUPITER Rotates ______________: ________________ in the S.S.
rapidly/fastest
JUPITER has a relatively small ___________ core (but still about 10x size of Earth)
rocky
HOW do magnetic fields form?
speed+conductivity (conductive materials in core)
dynamo effect
the model that explains the Earth's and other planets' magnetic fields as being due to electric currents flowing within molten iron cores.
DIFFERENTIAL ROTATION
the rotation of a star or planet at different speeds at its equator and poles *something the jovians go through b/c they're not solid, so they have to measure the rotation at different spots, rather than a whole body*
WHY does IO not crater?
they fill in too fast -youngest surface of any solar system object
JUPITER MOLECULAR HYDROGEN
•20,000 km thick
JUPITER METALLIC HYDROGEN
•40,000 km thick •good conductor - one reason for high magnetic field
CALLISTO
•Furthest from Jupiter •Ganymede Twin; no evidence of plate activity •Valhalla - 3000 km in size - due to impact and frozen before it could disperse - has dark and light regions
WHAT is the composition of Jupiter's atmosphere?
•H - 86.1% •He - 13.8 % •Methane, ammonia, water vapor - 1% *Mostly H and He - like the Sun*