Rings, Moons and Pluto, Schemes and Mind Maps of Astronomy

Download Rings, Moons and Pluto and more Schemes and Mind Maps Astronomy in PDF only on Docsity!

Rings, Moons and Pluto

September 30, 2002

Introduction

2) Rings 3) Moons 4) Pluto

Review

„

Outer Planets

„ Interior/Exterior „ Gas Giants „ Jupiter & Saturn „ Ice Giants „ Uranus & Neptune „

Tides

„ Forces „ Tidal Resonances

Saturn’s Rings

„

Complicated, intense ring system

„ Ring A – bright, narrow, with gaps „ Ring B – very wide with no gaps „ Rings C&D – close to the planet „ Rings E&G – very large, diffuse outer rings „

Cassini Division – separates the A&B rings

Other Rings

„

Jupiter

„ best seen lit from behind „ diffuse „

Uranus

„ 10 narrow rings „ one wide ring close to planet „

Neptune

„ 3 narrow, 3 wide „ arc-like segments within rings

Ring Stability

„

Rings want to spread out and disappear

„

Can be held together by gravity andcollisions

„ Temporary „

Can be held together by moons

„ Remember shepherd moons in

To Boldly Go

Moons

„ There are more than 90 moons – mostly in theouter Solar System „ Only 3 around the inner planets, Earth & Mars (2) „ Wide range of sizes „ Generally low mass and little or noatmosphere „ Categories – Geological Activity „ Currently active (confirmed) „ May be active „ Probably was active at one time „ Dead Moons

„

Moon of Jupiter

„ Very close to Jupiter „ Tidal forces heat the interior „

Very volcanically active

„ Most volcanically active object in the SolarSystem „ Several plumes observed by Voyager „ More than 300 volcanic sites have beenidentified „ Probably has turned itself inside out at leastonce

Io

May Be Active

„ No observed activity, but evidence of activity atone time „ less craters, more smooth surfaces „ Europa (Jupiter) „ rock with icy crust „ may contain liquid water below surface „ evidence of internal heating „ Titan (Saturn) „ dense atmosphere (35% denserthan Earth’s) „ evidence of water ice and liquidmethane

Dead Moons

„

No signs of geological activity sinceformation

„ lots of craters „

Include:

„ irregular moons „ often captured or remnants of older moons „ Callisto (Saturn) „ confusing data on formation/history „ Umbriel (Uranus) „ why wasn’t it active?

Pluto

„ Farthest of the planets (most of the time) „ Occasionally is closer than Neptune (elliptical orbit) „ Orbit takes 248 Earth years „ Charon „ Moon with 1/2 mass of Pluto „ Pluto and Charon are tidal locked „ Mass of Pluto + Charon is 1/ th that of Earth „ Rock, ice and methane „ Similar to Europa „ Like other objects in Kuiper Belt… „ Today, would not be classified a planet

Meteors

„

Parts of the Solar System that come tous

„ some of the moststudied astronomicalobjects „

Categories

„ stony meteorites „ iron meteorites „ stony-iron meteorites „ category depends upon source of meteor

Asteroids

„

Classification depends upon formation

„

C-type

„ cooled without differentiation „ snapshot of material of early Solar System „

S-type

„ differentiated – iron core, silicate crust „

M-type

„ iron core without crust