Week 9: Jupiter

Jupiter facts:

  • largest planet from our solar system

  • 5th planet from the Sun

  • Jovian planet

  • Jupiter: King of the Gods

  • first telescopically observed by Galileo in 1609

  • distance from the sun: 480 million miles or 5.2 au

    • more than 5.2x distance from earth to sun

      • au = distance from earth to sun

  • Diameter: 88,000 miles or 11 Earth diameters

    • can fit 11 earths side by side to be same size and Jupiter

    • more than 1,300 Earths in volume!

      • 1300 earths’ can fit inside Jupiter

      • Largest planet in entire solar system!

  • mass: 318 Earth masses

  • Axial Tilt: 3 degrees

  • Density: 1.3g/cm3

    • less than 1/4th Earth’s density!

      • not very dense compared to earth

  • Composed of gas and liquid, mostly hydrogen (around 85%)

    • similar to the sun

  • Surface Gravity = 2.5 g

    • don’t have solid surface, measured from top of cloud

Jupiter’s Rotation and Revolution

  • Rotation rate: 9 hours 50 minutes

    • fastest of all the major planets

      • spins faster due it being formed by bigger cloud than earth, causing angular momentum

        • gravity pulled the vast cloud of gas and dust inward to form Jupiter, the planet shrank in size, causing its rotation rate to accelerate

          • similar to a spinning ice skater pulling in their arms. 

  • Exhibits differential rotation (not all parts of Jupiter rotates at same speed)

    • poles (top and bottom of planet) rotate 5 minutes slower than the equator (middle)

  • Revolution period: about 12 years

    • revolution period: how much time it takes to orbit the sun

Jupiter Clouds

  • Temperature at cloud tops: around 166 degrees F

    • reddish bands = belts

      • combination of ammonia, hydrogen, and sulfur

        • called ammonia hydrosulfide

      • lower altitude

      • belts move faster than zones

    • Whiteish bands = zones

      • frozen ammonia

      • higher altitude

      • zones move faster than belts

        white dots at bottom are called pearls

  • gas goes up in atmosphere (from red to white) then freezes, turning white

    gas is going up in atmosphere (from red to white) then freezes, turning white

Great Red Spot

  • giant storm (winds, similar to hurricane)

    • 2-3 Earth diameters! (can fit 2-3 earths inside of it! but getting smaller)

      • rotates once every 6 days

      • formed by winds blowing opposite direction and interacting

        • driven by internal heat

      • at least 200 years old

Jupiter’s Interior

  • layers are NOT distinct

    • more of gradual change between layers

    • as you move in towards center of Jupiter, becomes denser and thicker gases, then liquid hydrogen, until you reach solid core

      no distinct layers like looks like in photo

Jupiter’s Opposition

  • opposition: when a planet is on the direct opposite side of Earth from the sun

    • during this time, Jupiter will be closest it can get to Earth

    • occurred December 7th, 2024

      • next one occurs around January 2026

Is Jupiter a Brown Dwarf?

  • Brown Dwarf: failed star

  • Jupiter has a very similar to a chemical composition to typical stars

    • but not enough mass

      • needs to be 70-80x more mass to be a star

    • Jupiter is not a brown dwarf

      • needs to have at least 10x more mass to be a brown dwarf (failed star)

Magnetic Field of Jupiter

  • Jupiter’s magnetic field is 19,000x stronger than Earth’s

    • has a very very strong magnetic field

      • can fry our electronics when we send spacecraft near the planet, making it crucial to design probes with robust shielding to withstand the intense radiation.

Jupiter’s Auroras

  • Auroras are created as solar wind interacts with magnetic poles

    • solar wind (charged particles) slam into magnetic field

      • causes gases in these areas to get excited and glow

Jupiter has Rings!

  • Jupiter has tiny rings

    • ring system discovered as Voyager 1 in 1979

      • (all of jovian planets have rings)

Galileo (the spacecraft)

  • launched in 1989

  • orbited Jupiter from 1995- 2003

  • first spacecraft to orbit an outer planet

  • dropped a probe that fell through Jupiter’s atmosphere, sending back data

    • only lasted an hour due to being crushed by all the pressure in Jupiter’s atmosphere

Juno Spacecraft

  • launched in 2011

    • arrived in 2016 and is still operating

  • most recent spacecraft at Jupiter

Jupiter’s Natural Satellites

  • 95 official natural satellites, but likely more!

  • 4 Galilean Moons:

    • io

    • Europa

    • Ganymede

    • Callisto

      • discovered by Galileo

Io (spelled io)

  • few impact craters

  • continually resurfaced by volcanic activity

  • most volcanically active body in the solar system!

    glow on top is volcano blowing gases upward

Europa

  • surface composition: water ice

  • scientist think there is a liquid water ocean below the icy surface

  • interior warmed by tidal stretching, like io

    • warm salt water = possibility of life??

Ganymede

  • solar system’s largest satellite

    • larger than Mercury and Pluto!

      • but does not orbit the sun (orbits Jupiter) so it is not a planet

  • only satellite with its own magnetic field

  • named after Jupiter’s eagle bird friend / servant

Callisto

  • ancient surface: 4 billion years old!

  • most heavily created object in the solar system

    line = crater chain, caused by Jupiter's strong magnetic field ripping up comet but Callisto got in the way and took the impact

Comet Shoemaker-Levy 9

  • comet that passed within the Roche limit and was ripped apart

    • stretched into a string of 23 fragments

  • first impact with Jupiter was July 16th, 1994

    purple dots = big impact zones of Comet Shoemaker-Levy 9

Jupiter’s Impacts

  • Jupiter takes a lot of hits

  • we think it could be responsible for absorbing / deflecting objects that could head towards Earth

Jupiter’s Trojans

  • Jupiter’s strong magnetic field causes little planets / astroids to stay within its orbits

    • Lagrange points: weird point of gravitational stability where objects (planets / astroids) can remain stable near a massive body like Jupiter

      green dots = Jupiter's trojans

VIDEO NOTES

  • largest planet of solar system

  • Jupiter is called '“gas giant”

  • one day on Jupiter is mere 10 hours long

    • thats the fastest spin in the solar system

  • brightest planet in the solar system

  • jupiter’s atmosphere is banded, with multiple stripes running parallel to its equator

  • belts = lighter colored stripes

  • zones = darker colored stripes     

    • belts and zones formed due to convection in jupiter

  • radiates more heat than received from the sun