The Solar System

Terms Ecliptic –Imaginary plane within which the 8 major planets orbit the Sun –Apparent path of Sun across the sky as seen from Earth PSCI 131: The Solar System

Terms: Ecliptic PSCI 131: The Solar System From: Wikipedia.org

The Solar System The Early Solar System Overview The Terrestrial Planets The Jovian Planets Dwarf Planets Asteroids Comets Meteoroids PSCI 131: The Solar System

The Early Solar System

PSCI 131: The Solar System – The Early Solar System From: jcconwell.wordpress.comjcconwell.wordpress.com The Nebular Theory

The Early Solar System PSCI 131: The Solar System – The Early Solar System Planets formed from collisions of smaller objects The Nebular Theory

Solar System Overview

Overview of the Solar System Sun: >99% of solar system’s mass Major planets –4 terrestrial –4 Jovian Dwarf planets –5 recognized so far by IAU PSCI 131: The Solar System – Overview

Overview of the Solar System Asteroids, comets, meteoroids –Leftover material from solar system formation –Fragments from collisions Dust, gas, radiation PSCI 131: The Solar System – Overview

The 8 Major Planets

What Is A Major Planet? Spherical Orbits Sun Not a moon Has cleared its orbital path of other objects PSCI 131: The Solar System

Major Planets and Sun PSCI 131: The Solar System – The 8 Major Planets The major planets, shown to scale

The Four Terrestrial Planets “Terrestrial”: Earth-like Mercury, Venus, Earth, Mars PSCI 131: The Solar System – Terrestrial Planets The terrestrial planets, shown to scale From: wikipedia.org

The Four Terrestrial Planets Small Rocky Dense Thin atmospheres Short years Long days Main heat source: Sun PSCI 131: The Solar System – Terrestrial Planets EARTH VENUS MARS MERCURY From: wikipedia.org

Mercury PSCI 131: The Solar System – Terrestrial Planets From: wwu.edu From: wikipedia.org Orbital period: 88 days Rotation period: 59 days Temp range: -270° F – 870° F Atmosphere: None

Venus PSCI 131: The Solar System – Terrestrial Planets Cloud cover of Venus. From: ircamera.as.arizona.edu Surface of Venus, photographed with cloud-penetrating radar. From: annesastronomynews.com Orbital period: 225 days Rotation period: 243 days Temperature: 900° F Atmosphere: 97% CO 2

Earth PSCI 131: The Solar System – Terrestrial Planets Earth from low-altitude orbit. From: astexhibits.com Earth as seen from the Moon. From: science1.nasa.gov Orbital period: days Rotation period: 23 hr 56 min Temperature: 58° F (2012 average) Atmosphere: Nitrogen, oxygen, argon, water, CO 2

Mars PSCI 131: The Solar System – Terrestrial Planets Mars from low-altitude orbit, showing atmosphere. From: wikipedia.org Orbital period: 687 days Rotation period: 24 hr 37 min Temperature: -80° F (average) Atmosphere: Thin, CO 2

Mars PSCI 131: The Solar System – Terrestrial Planets Volcanoes and water ice clouds on Mars. From: jpl.nasa.gov Olympus Mons volcano Olympus Mons. Cliff at base is 5 miles high. Inset shows height compared to Earth mountains. From: wikipedia.org

The Four Jovian Planets “Jovian”: Jupiter-like Jupiter, Saturn, Uranus, Neptune PSCI 131: The Solar System – Jovian Planets The Jovian planets, shown to scale From: cseligman.com

The Four Jovian Planets Large Gas & ice Low density Long years Short days Main heat source: internal (from gravitational compression) PSCI 131: The Solar System – Jovian Planets Jovian planets compared to the Sun and Earth (far right) Modified from: wikipedia.org

Jupiter PSCI 131: The Solar System – Jovian Planets Jupiter as it would look if it were the same distance from Earth as the Moon. From: tholtz.com Orbital period: 12 years Rotation period: 9 hr 56 min Temperature: -234° F (cloud tops) Atmosphere: Hydrogen, helium From: photojournal.jpl.nasa.gov

Jupiter’s Atmosphere PSCI 131: The Solar System – Jovian Planets Cross-section of Jupiter compared with Earth. 125°K is about -234°F; 2000°K is about 3100°F. Mostly H and He Would have become a sun if it had been bigger Pressure within atmosphere is high enough to make liquid and metallic hydrogen

Jupiter: The Great Red Spot PSCI 131: The Solar System – Jovian Planets High-res photo of the Great Red Spot, an ancient storm the size of three Earths.

Saturn PSCI 131: The Solar System – Jovian Planets Saturn imaged by the Cassini-Huygens spacecraft, From: nasa.gov Orbital period: 30 years Rotation period: 10 hr 30 min Temperature: -288° F (cloud tops) Atmosphere: Hydrogen, helium Saturn’s rings and Earth, taken by Cassini-Huygens spacecraft, From: nasa.gov Earth as seen from Saturn

Saturn’s Moon Titan PSCI 131: The Solar System – Jovian Planets Comparison of Titan with Earth and Earth’s moon. Atmosphere: Nitrogen, methane Only moon known to have an atmosphere Bodies of stable liquid on surface Methane, ethane Titan’s surface. From: nasa.gov

Orbital period: 84 years Rotation period: 17 hr 14 min Temperature: -357° F (cloud tops) Atmosphere: Hydrogen, helium, frozen ammonia and methane Rotates on its side: Uranus PSCI 131: The Solar System – Jovian Planets Uranus showing rings and cloud bands. From: nasa.gov Axis

Orbital period: 165 years Rotation period: 16 hr 7 min Temperature: -392° F (cloud tops) Atmosphere: Hydrogen, helium, frozen ammonia and methane Neptune PSCI 131: The Solar System – Jovian Planets Neptune with cloud bands, cirrus clouds (white) and storm systems (dark spots). From: nasa.gov

The Dwarf Planets PSCI 131: The Solar System

What Is A Dwarf Planet? Spherical Orbits Sun Not a moon Has NOT cleared its orbital path of other objects PSCI 131: The Solar System

Five Recognized Dwarf Planets (Listed in order of decreasing size) Eris Pluto Makemake Haumea Ceres All are located in “debris belts” PSCI 131: The Solar System – Dwarf Planets

Debris Belt Locations Orbit of Earth Orbit of Mars ASTEROID BELT SUN KUIPER BELT Orbit of Uranus Orbit of Neptune

Debris Belt Locations ASTEROID BELT KUIPER BELT Orbit of Uranus Orbit of Neptune OORT CLOUD

Five Recognized Dwarf Planets Eris: Kuiper Belt Pluto: Kuiper Belt Makemake: Kuiper Belt Haumea: Kuiper Belt Ceres: Asteroid Belt Oort Cloud: No recognized dwarf planets; trillions of comets PSCI 131: The Solar System – Dwarf Planets

The Smaller Objects: Asteroids, Comets, & Meteoroids PSCI 131: The Solar System

Asteroids Size: 10s to 100s of miles Shape: Irregular Composition: Rock, metal Atmosphere: None Location: Mostly in Asteroid Belt between Mars and Jupiter PSCI 131: The Solar System – Smaller Objects

(doesn’t look like this) PSCI 131: The Solar System – Smaller Objects The Asteroid Belt

What Does the Asteroid Belt Look Like? PSCI 131: The Solar System – Smaller Objects It’s mostly empty space

Asteroids: Earth Crossers PSCI 131: The Solar System – Smaller Objects

Comets Size: average diameter about 5 miles Shape: Irregular Composition: Ice, rock & metal fragments Atmosphere: None Location: Kuiper Belt & Oort Cloud PSCI 131: The Solar System – Smaller Objects Halley’s Comet, 1986 From: dailygalaxy.com

Comets PSCI 131: The Solar System – Smaller Objects Structure of a comet

Comets PSCI 131: The Solar System – Smaller Objects A comet’s coma and tail only form near the Sun. The tail always points away from the Sun.

Comets PSCI 131: The Solar System – Smaller Objects Comet Shoemaker-Levy struck Jupiter in 1994.

Meteors Size: sand grain (average) Composition: Rock, metal PSCI 131: The Solar System – Smaller Objects

Meteors Meteor: within a planet’s atmosphere Meteorite: has struck the ground Meteoroid: still in space PSCI 131: The Solar System – Smaller Objects

The Chelyabinsk “Meteor”, February 15, 2013 Approx. mass: 11K tons Approx. size: 60 ft Velocity: 41K mph Altitude of airburst: 76K feet Energy: 500K tons of TNT Injuries: 1,491 Damage: 7,200 buildings PSCI 131: The Solar System – Smaller Objects VIDEO: Chelyabinsk meteor airburst and building damageChelyabinsk meteor airburst and building damage