Tour of the Solar System

General Properties of the Solar System There are two classes of planets:  The Terrestrial planets are small, solid bodies (rocks or iron) in the inner part of the Solar System.  The Jovian planets are hydrogen-rich gas giants in the outer part of the Solar System. Each planet (except for Pluto) is in a roughly circular (elliptical) orbit in the plane of the ecliptic, moving west-to- east in the sky.

General Properties of the Solar System There are two classes of planets:  The Terrestrial planets are small, solid bodies (rocks or iron) in the inner part of the Solar System.  The Jovian planets are hydrogen-rich gas giants in the outer part of the Solar System. Each planet (except for Pluto) is in a elliptical orbit in the plane of the ecliptic, moving west-to-east in the sky. Between Mars and Jupiter there are large numbers of small asteroids. Outside the orbit of Neptune is the Kuiper Belt of comets. Far past Pluto is the Oort Cloud of comets.

The Planets

Mercury

The Planets Name Distance (A.U.) Period Mass (M  ) Density (water) Temp (C) min/max Rotation (time) Tilt Mercury d / d 7°7°

Mercury

resonance Mercury notes: many impact craters (looks like the Moon); very dense (mostly iron); rotation period exactly 2/3 of its orbital period (a resonance); very large day/night temperature difference; no atmosphere; no moon

The Planets Name Distance (A.U.) Period Mass (M  ) Density (water) Temp (C) min/max Rotation (time) Tilt Mercury d / d 7°7° Venus d d 2°2°

Venus optical Venus notes: similar in size and mass to earth; extremely thick CO 2 atmosphere; sulfuric acid clouds; hottest planet in the Solar System; little temperature variance; evidence of volcanos on surface; rotates slowly (backwards); some impact craters; no moon

Venus and Jupiter

The Planets Name Distance (A.U.) Period Mass (M  ) Density (water) Temp (C) min/max Rotation (time) Tilt Mercury0.3988d / d 7°7° Venus d d 2°2° Earth d /+5024 h 23° Moon / d 6°6°

Earth and Moon Earth/Moon notes: double planet (Moon similar in size to earth); extremely different surface conditions; Moon keeps its same side to the earth at all times

Earth Earth notes: liquid water on surface; very dense (mostly iron); atmosphere of N 2 and O 2 (with trace amounts of CO 2 ); a few impact craters; small difference in day/night temperature; evidence of volcanos and tectonic activity; water vapor clouds

The Moon Moon notes: many impact craters; less dense than Earth (mostly rock); no atmosphere; large day/night temperature difference; evidence of past lava flows (only on side facing Earth); no present volcanos or tectonic activity

The Planets Name Distance (A.U.) Period (yr) Mass (M  ) Density (water) Temp (C) min/max Rotation (time) Tilt Mercury0.3988d / d 7°7° Venus d d 2°2° Earth1.0365d /+5024 h 23° Moon / d 6°6° Mars1.5687d /+2024 h 37 m 24°

Mars Mars notes: medium density (rocks); polar ice caps (H 2 O and CO 2 ); thin CO 2 atmosphere; moderate daytime/night temperature changes; some impact craters; large canyons and volcanos; evidence for old river beds; dust storms; two small moons

Mars

Sand Dunes on Mars

Mars moons Deimos and Phobos

The Planets Name Distance (A.U.) Period (yr) Mass (M  ) Density (water) Temp (C) min/max Rotation (time) Tilt Mercury0.3988d / d 7°7° Venus d d 2°2° Earth1.0365d /+5024 h 23° Moon / d 6°6° Mars d /+2024 h 37 m 24° Jupiter years h 50 m 1°1°

Jupiter Jupiter notes: gas giant (mostly H and He, with CH 4 and NH 3 ); strong winds; faint system of rings; rapid rotation (and slightly flattened); 4 large, many smaller moons; emits more energy than it receives from the Sun; contains more mass than all the other planets put together, red spot = Giant hurricane lasting 300 years 2 times the size of Earth.

Jupiter’s Rings

Jupiter and Io

Jupiter’s Galilean Moons Io: density of 3.5; many volcanos; no impact craters Europa: density of 3.0; smooth icy surface; few impact craters Ganymede: density of 1.9; grooved surface; many impact craters Callisto:density of 1.8; covered with craters IoEuropa GanymedeCallisto

Europa

The Planets Name Distance (A.U.) Perio d (yr) Mass (M  ) Density (water) Temp (C) min/max Rotation (time) Tilt Mercury0.3988d / d 7°7° Venus d d 2°2° Earth1.0365d /+5024 h 23° Moon / d 6°6° Mars1.5687d /+2024 h 37 m 24° Jupiter years h 50 m 1°1° Saturn years h 39 m 2°2°

Saturn Saturn notes: gas giant (mostly H and He, with CH 4 and NH 3 ); strong winds; bright complex system of rings; rapid rotation (and flattened); 1 large moon (Titan) with atmosphere plus many smaller moons; density less than water (it floats)!

Saturn and Titan

Saturn’s Tethys

Saturn’s Moons Titan: thick atmosphere of mostly CH 4 and NH 3 ; other moons are mostly icy, but show a wide variety of properties

The Planets Name Distance (A.U.) Period (yr) Mass (M  ) Density (water) Temp (C) min/max Rotation (time) Tilt Mercury0.3988d / d 7°7° Venus d d 2°2° Earth1.0365d /+5024 h 23° Moon / d 6°6° Mars1.5687d /+2024 h 37 m 24° Jupiter y h 50 m 1°1° Saturn y h 39 m 2°2° Uranus19.284y h 14 m 98°

Uranus Uranus notes: gas giant (mostly H and He, with CH 4 and NH 3 ); discovered by Herschel (with telescope) in 1781; tipped 98° from ecliptic plane; moderately complex ring system; many icy moons with odd features

Uranus’ Tilt Miranda Moons of Uranus include: Belinda, Rosalind, Portia, Bianca, Cressida, Juliet, Desdemona, Puck, and Miranda

The Planets Name Distance (A.U.) Period (yr) Mass (M  ) Density (water) Temp (C) min/max Rotation (time) Tilt Mercury0.3988d / d 7°7° Venus d d 177° Earth1.0365d /+5024 h 23° Moon / d 6°6° Mars1.5687d /+2024 h 37 m 24° Jupiter y h 50 m 1°1° Saturn y h 39 m 2°2° Uranus19.284y h 14 m 98° Neptune y h 03 m 29°

Neptune Neptune notes: gas giant (mostly H and He, with CH 4 and NH 3 ); existence and position predicted mathematically in 1843 by John Couch Adams and Urbain LeVerrier; moderately complex ring system; many icy moons

Name Distance (A.U.) Period (yr) Mass (M  ) Density (water) Temp (C) min/max Rotation (time) Tilt Mercury0.3988d / d 7°7° Venus d d 2°2° Earth1.0365d /+5024 h 23° Moon / d 6°6° Mars1.5687d /+2024 h 37 m 24° Jupiter y h 50 m 1°1° Saturn y h 39 m 2°2° Uranus19.284y h 14 m 98° Neptune y h 03 m 2°2° Pluto y d 9 h 122°

Pluto- the “ex-planet” Pluto notes: double planet (with Charon); very small; discovered in 1930 by Clyde Tombaugh (if discovered today, would not be called a planet); orbit around the Sun is very elliptical, and is sometimes closer than Neptune); icy, similar to moons of outer planets

Pluto

Asteroids Asteroid notes: most asteroids are small iron bodies; most are between Mars and Jupiter (where Bode’s Law predicts a planet); a few (called Apollo asteroids) cross the Earth’s orbit; the total mass is less than M 

Comets Kuiper belt Oort Cloud Comets notes: composition similar to dirty iceballs; many are in the Kuiper belt, outside the orbit of Neptune; most are in the Oort Cloud between 20,000 and 100,000 A.U. from the Sun; the comets we see are in highly elliptical orbits

Message to outer space