The Solar System: Saturn's Satellites - X-ray and Gamma-ray Astronomy Appendixes Index

1068 Pages·2009·19.3 MB·English

by  David G. Fisher

Volume 1
Archaeoastronomy—Jupiter’s Ring System
Editors
David G. Fisher and Richard R. Erickson
Lycoming College
Salem Press
Pasadena, California Hackensack, New Jersey
Editor in Chief:Dawn P. Dawson
Editorial Director:Christina J. Moose Production Editor:Joyce I. Buchea
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∞ ThepaperusedinthesevolumesconformstotheAmericanNationalStandardforPermanence
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Library of Congress Cataloging-in-Publication Data
The solar system / editors, David G. Fisher, Richard R. Erickson.
p. cm.
Includes bibliographical references and index.
ISBN 978-1-58765-530-2 (set : alk. paper) — ISBN 978-1-58765-531-9 (v. 1 : alk. paper) —
ISBN 978-1-58765-532-6 (v. 2 : alk. paper) — ISBN 978-1-58765-533-3 (v. 3 : alk. paper) —
1. Solar system. 2. Astronomy. I. Fisher, David G. II. Erickson, Richard R., 1945-
QB501.S627 2010
523.2—dc22
2009013008
First Printing
printed in the united states of america
Publisher’s Note
The Solar System covers 180 features of knowledge of the solar system—from Pioneer
Earth’s solar system, including every major andVoyagertothedatafromGalileo,theHub-
bodyandphenomenon:fromtheastrophysicsof bleSpaceTelescope,Cassini-Huygens,NASA’s
theSunandthemajorfeaturesofeveryplanet, New Horizons program, and the latest Mars
theirsatellites,andsmallbodiessuchascomets rovers.
andasteroids,toscientificmethodologies,inter-
planetary phenomena, and related topics in Organization and Format
stellarastronomyandcosmology.Authoritative Coverage is presented in an A-Z format—
and essential to the core curriculum in astron- from “Archaeoastronomy” and “Asteroids”
omyandEarthsciences,thesethreevolumesof- through “Venus’s Volcanoes” to “X-Ray and
fer both students and general library patrons Gamma-RayAstronomy”—andissupplemented
detailedbasicinformationonallmajoraspects byhundredsofdiagramsandphotos.Forthose
ofEarth’ssolarsystem.Noothergeneralrefer- wishing instant access to essays grouped by
ence dedicated to the solar system is this com- planetary system, a Category List appears in
plete and up to date, incorporating the latest the front of every volume.
perspectives offered by space telescopes, inter- The set’s essays fall into one or more of the
planetary probes, and planetary missions. following categories: the Cosmological Context
(13),Earth(25),theJovianSystem(11),Lifein
Scope and Coverage the Solar System (5), Mars (11), Mercury (1),
Theessaysaredesignedtomeettheneedsof Natural Planetary Satellites (23), the Neptu-
both general readers and students enrolled in nian System (7), Planets and Planetology (62),
coursesintheEarthsciences(with25topicson the Saturnian System (8), Scientific Methods
Earth’s geology, geophysics, and astrophysics (13), Small Bodies (17), the Solar System as a
alone), as well as astronomy, planetology, and Whole(7),theStellarContext(13),theSun(20),
cosmology.Anolderedition,underSalem’sMa- the Uranian System (7), and Venus (5).
gill’s Choice imprint (1998), now more than a Every essay ranges in length from 2,000 to
decade old, here receives a complete overhaul. 5,000words(3to7pages)andoffersnotonlya
For this new edition, we have added 58 topics complete overview of the topic but also an as-
and have thoroughly expanded every essay, sessmentofknowledgegained,methodsofstudy,
from the text through the bibliographies, to or applications. Each essay displays standard
bring the coverage up to date. ready-reference top matter and subsections:
The result is the most thorough reference (cid:127) Essay Title: Topic name, from “Archaeo-
available on our expanding understanding of astronomy” and “Asteroids” through “Mars:
Earth’suniversalneighborhood.Alloftheorigi- PossibleLife”to“X-RayandGamma-RayAs-
nal 122 essays, as well as the 58 new topics, tronomy.”
werereviewedandupdatedbyProfessorsDavid (cid:127) Categories: Lists scientific subdisciplines
G.FisherandRichardR.EricksonofLycoming relevant to standard undergraduate cur-
College’s Department of Astronomy. They not ricula.
only have added key developments of the past (cid:127) Significance: Summarizes the importance
decadebutalsohavescrutinizedandheavilyed- of the topic and current state of our knowl-
ited the existing text to ensure current accu- edge.
racy—oftenincreasingthelengthsofoldessays (cid:127) Overview: Rehearses the main facts about
bymorethanathird.Suchrevisionandexpan- the topic.
sionwereessentialinordertotakeintoaccount (cid:127) KnowledgeGainedorMethodsofStudy
the many planetary and interplanetary mis- or Applications: Headed as appropriate,
sions that have exponentially increased our this section details how the topic is investi-
v
The Solar System
gated,whatscientificknowledgewehaveac- naked eye, through a camera, or through sun-
cumulated, or the uses of the knowledge we glassesorothersuchdevices,whichoffernopro-
have gained. tectionandcancausesignificantdamagetothe
(cid:127) Context:Addressesthetopicfromthelarger eyes.
perspectiveofthehistoryofsolarsystemsci-
ence and its relevance for humankind. The Editors and Contributors
(cid:127) Byline:Allessaysaresignedbythescholars Salem Press extends its appreciation to all
whowrotethem;theseexpertsarealsolisted, involved in the development of this work. Spe-
with their academic affiliations, in the front cial thanks go to the set’s editors, David G.
matter to Volume 1. Fisher and Richard R. Erickson of Lycoming
(cid:127) FurtherReading:Anannotatedselectionof College’sDepartmentofAstronomy,alongwith
the most important print resources for fur- their assistant, graduate student Jennifer L.
ther study. Campbell, who performed much of the manu-
(cid:127) See also: Lists cross-references to other es- script editing. Professor Fisher is Professor of
says inThe Solar Systemon related topics. Physics and Astronomy as well as an accom-
plished spaceflight historian. In the latter ca-
Special Features pacity, Dr. Fisher served as co-editor of Salem
Several special resources and finding aids Press’sthree-volumeUSAinSpace,ThirdEdi-
enhance coverage and access to the set’s con- tion (2006). He has published extensively on
tents.Eachvolume’sfrontmatterincludesboth spaceflighthistory(concerningnotonlyAmeri-
an Alphabetical List of Contents (A-Z) and a canroboticandcrewedspaceprogramsbutalso
Category List of Contents (with essays ar- Soviet/Russian and other international space
rangedbyareaofthesolarsystemstudied).The projects), physics and physics education, and
setislavishlyillustratedwithphotos,sidebars, popular science topics. Professor Erickson is
diagrams, and tables. A Glossary, a General Associate Professor of Astronomy and Physics
Bibliography, a list of Web Sites, and full Sub- andDirectoroftheDetwilerPlanetariumatLy-
ject Index round out the set. coming College. Dr. Erickson has professional
interestsinandhaspublishedarticlesandpa-
Miscellaneous Notes persconcerningstellardynamics,nearbystars,
The editors have endeavored to follow stan- variablestars,galacticstructure,relativityand
dard stylistics and usage throughout, using cosmology, impacts and extinctions, and the
NASAsourcesinmostcases.Thewords“natu- modeling of the physics of impact events.
ral satellite,” “satellite” (where unambiguous The essays were written and are signed by
with technology), and “moon” are used inter- morethaneightyscientists,scholars,andother
changeably.Itisimportanttonotethatseveral experts,alistofwhomwillbefoundinthefol-
essaysrefertoobservancesoftheSuninoptical lowing pages, accompanied by their academic
(visible) light,andweremindreadersthatone affiliations.Withouttheircontributions,aproj-
should never look directly at the Sun with the ect of this magnitude would not be possible.
vi
Contributors
Stephen R. Addison John H. Corbet Donald R. Franceschetti
University of Central Arkansas Memphis State University Memphis State University
Arthur L. Alt John A. Cramer Roberto Garza
College of Great Falls Oglethorpe University San Antonio College
Michael S. Ameigh Robert L. Cullers Karl Giberson
St. Bonaventure University Kansas State University Eastern Nazarene College
Victor R. Baker Joseph Di Rienzi David Godfrey
University of Arizona College of Notre Dame of National Optical Astronomy
Maryland Observatory
Iona C. Baldridge
Lubbock Christian University Bruce D. Dod Gregory A. Good
Mercer University West Virginia University
Thomas W. Becker
Webster University Dave Dooling C. Alton Hassell
D2 Associates Baylor University
Reta Beebe
New Mexico State University Steven I. Dutch Robert M. Hawthorne, Jr.
University of Wisconsin— Marlboro, Vermont
Timothy C. Beers
Green Bay
Michigan State University Paul A. Heckert
John J. Dykla Western Carolina University
Raymond D. Benge, Jr.
Loyola University of Chicago
Tarrant County College David Wason Hollar, Jr.
Richard R. Erickson Rockingham Community College
Alvin K. Benson
Lycoming College
Utah Valley University Earl G. Hoover
Dale C. Ferguson Science Writer
John L. Berkley
Baldwin-Wallace College
State University of New York Hugh S. Hudson
College at Fredonia David G. Fisher University of California,
Lycoming College San Diego
Larry M. Browning
South Dakota State University Richard R. Fisher Brian Jones
National Center for Atmospheric Science Writer
Michael L. Broyles
Research
Collin County Community Richard C. Jones
College Gerald J. Fishman Texas A&M University
National Aeronautics and Space
David S. Brumbaugh Pamela R. Justice
Administration
Northern Arizona University Collin County Community
Michael P. Fitzgerald College
Jessica Lynn Bugno
Vestal, New York
Lycoming College Karen N. Kähler
Dennis R. Flentge Pasadena, California
Jennifer Campbell
Cedarville College
Lycoming College Christopher Keating
George J. Flynn University of South Dakota
Dennis Chamberland
State University of New York
Science Writer John P. Kenny
College at Plattsburgh
Bradley University
D. K. Chowdhury
John W. Foster
Indiana University and Purdue Firman D. King
Illinois State University
University at Fort Wayne University of South Florida
vii
The Solar System
Richard S. Knapp Anthony J. Nicastro Charles W. Rogers
Belhaven College West Chester University of Southwestern Oklahoma State
Pennsylvania University
Narayanan M. Komerath
Georgia Institute of Technology Divonna Ogier David M. Schlom
Oregon Museum of Science California State University,
Kristine Larsen
and Industry Chico
Central Connecticut State
University Steven C. Okulewicz Stephen J. Shulik
City University of New York, Clarion University of
Joel S. Levine
Hunter College Pennsylvania
National Aeronautics and
Space Administration Satya Pal R. Baird Shuman
New York Institute of University of Illinois at Urbana-
James C. LoPresto
Technology Champaign
Edinboro University of
Pennsylvania Robert J. Paradowski Paul P. Sipiera
Rochester Institute of William Rainey Harper College
George E. McCluskey, Jr.
Technology
Lehigh University Billy R. Smith, Jr.
Jennifer L. Piatek Anne Arundel Community
Michael L. McKinney
Central Connecticut State College
University of Tennessee,
University
Knoxville Roger Smith
George R. Plitnik Willamette University
V. L. Madhyastha
Frostburg State University
Fairleigh Dickinson Joseph L. Spradley
University Howard L. Poss Wheaton College, Illinois
Temple University
David W. Maguire James L. Whitford-Stark
C. S. Mott Community College Gregory J. Retallack Sul Ross State University
University of Oregon
Randall L. Milstein J. Wayne Wooten
Oregon State University Clark G. Reynolds Pensacola Junior College
College of Charleston
Brendan Mullan Clifton K. Yearley
Pennsylvania State Mike D. Reynolds State University of New York at
University University of North Florida Buffalo
Theresa A. Nagy J. A. Rial Ivan L. Zabilka
Pennsylvania State University of North Carolina at Lexington Kentucky Public
University Chapel Hill Schools
viii
Editors’ Introduction
Sinceancienttimes,humanshavelookedup andtheirplaceinit.Howweretheheavenscon-
attheskyandfeltbothfearsomeaweandwon- structed? What kept the clockwork timing of
drous amazement. The Sun, Moon, and stars mostoftheheavenssoperfect?Whatmadethe
have been worshiped as gods. They have in- planets move so differently? How and why did
spired poets, artists, and musicians. Scholars eclipses occur? Attempts to answer questions
and“ordinaryfolk”haveponderedthenatureof liketheseledtothefirstmodelsoftheuniverse
whattheysawintheskyandourrelationshipto and theories of cosmology.
it. A few hundred years b.c.e., Greek philoso-
Probablythefirstthingtobenoticedwasthat pher-scientistsdeterminedthatEarthmustbe
the celestial bodies moved across the sky from spherical,andtheycalculatedaremarkablyac-
east to west, suggesting the Earth was at the curatevalueforitscircumference,usinggeome-
centeroftheuniverseandeverythingrevolved try and a few simple observations. They cor-
around us. Most cultures recognized that the rectlyexplainedwhytheMoonwentthroughits
stars maintained the same patterns, moving phases and how eclipses of the Sun and Moon
acrosstheskyasgroups.Manydevelopedgrand occurred. They even deduced that the Moon is
stories about these patterns or constellations smaller and the Sun is larger than Earth.
which became part of their creation mytholo- MostGreekmodels,likethoseofmostother
gies. cultures, placed the Earth at the center of all
Intime,itwasnotedthatsomeofthepoints things. Not that some Greeks did not consider
oflightinthenightskydidnotmovequitethe the possibility that Earth moved, but such an
same as most stars did; they “wandered” ideaseemedtocontradicteverythingtheycould
against the background patterns of the so- perceive.Manycenturieswouldpassandmuch
called “fixed stars” that remained together in intense scientific debate would occur before it
thesameconstellation.These“wanderingstars” was accepted that while our existence in the
orplanets(fromtheGreekwordfor“wanderer”) universe may be special, our position is not.
acquiredspecialsignificanceinmanycultures. The transformation from an Earth-centered
Forexample,theMayanswereparticularlyin- universe to our present picture involved many
terested in Venus and kept meticulous records steps.Thefirststep,ledbythelikesofCoperni-
of where it was seen in the sky—sometimes in cus, Galileo, and Kepler during the 1500’s and
the east before sunrise and other times in the 1600’s,wasrecognizingthatEarthisoneofsev-
west after sunset. Some cultures developed eral planets orbiting the Sun. It was not until
ritesofworshipandbuilttemplesdevotedtothe the 1830’s that F. G. W. Struve, F. W. Bessel,
planets. Some regarded the planets and their and Thomas Henderson independently made
movementsasportentsordivinesignsofwhat the first measurements of stellar parallaxes
would happen here on Earth. (which is the only direct way to determine the
Eclipses and comets also evoked feelings of distancesofstars)andtherebyconfirmedwhat
fear and wonder. Because these visually spec- many had suspected, that stars really are
tacular events occur only occasionally, those thingsakintotheSunbutmuchfartheraway.
who successfully predicted them could acquire UltimatelytheSunwasfoundtobearatherav-
respectandpower.Thereisevidencethatoneof eragestar.ThelocationoftheSunandsolarsys-
Stonehenge’sfunctionsmighthavebeentopre- temintheouterpartoftheMilkyWaygalaxy’s
dict eclipses; if so, its builders had determined disk was determined by Harlow Shapley in
the pattern of eclipses several thousand years 1917.Afewyearslater,EdwinHubbledemon-
ago. stratedthattheso-called“spiralnebulae”really
Manyculturestriedtoexplainthenatureof are galaxies outside the Milky Way. He then
theuniverse(atleastwhattheycouldseeofit) discovered that most galaxy spectra are red-
ix
The Solar System
shifted, which led to the idea of an expanding turesshowedtheringsofSaturnandthecraters
universe. At the end of the twentieth century, of the Moon. Venus was perhaps a planet
the expansion of the universe was found to be warmerandwetterthanEarth,enjoyingalush,
accelerating, instead of slowing down as was swampy ecosystem filled with plant life. Mars
expected. Today, there is serious speculation was probably cold and dry, but some form of
by some scientists that our universe might be primitive microbes or plant life might have
just one of a multitude in a multidimensional adaptedtoliveintheharshenvironmentthere.
“multi-verse.” Earth’smoonwascoveredwithcratersprobably
Observationsofplanetarymotionsledtothe created by volcanic action. The moons of the
development of heliocentric models and Sir otherplanetswereprobablyuninterestingballs
Isaac Newton’s theory of gravity. Early ad- of ice (with the anticipated exception of Titan
vancesintelescopedesignandconstructional- about Saturn). Pluto was a small planet, per-
lowedintriguingbutuncleardetailstobeseen haps with some terrestrial characteristics, al-
on the planets. However, by the middle of the though the planet would be extremely cold. A
twentiethcentury,solarsystemstudieshadbe- very peaceful and safe solar system was de-
come a backwater of astronomy. Few astrono- scribed, in which nothing very dramatic hap-
mersthenwereactivelyengagedinanysortof pened. All of this was about to change, and a
planetaryorminorbodyresearch.(Anotableex- more dynamic solar system soon would be re-
ception was the Dutch-American astronomer vealed.
Gerard Kuiper.) When one of the editors Thedawnofthespaceagesparkedrenewed
(Erickson) was an undergraduate at the Uni- interestinthesolarsystem.EarlyLuna(Soviet)
versity of Minnesota in the early 1960’s, the and Pioneer (American) flyby missions at-
textbookusedinhisfirstastronomycoursehad tempted to reach the Moon in 1959. Only two
onlytwochaptersconsistingof85pages(outofa years after Fisher received All About the Uni-
total of 536) that dealt with the planets, their verseandAllAboutRockets,aspacecraftnamed
satellites, the asteroids, comets, and meteor- Mariner2flewrelativelyclosebyVenusandde-
oids. (In contrast, current introductory astron- termined that Venus was extraordinarily hot.
omytextbookstypicallydevoteaboutone-third No lush swamps existed, the surface tempera-
of their pages to these topics.) turewashotenoughtomeltlead,andtheatmo-
When the other editor (Fisher) was just five spherewasthickwithcarbondioxide.Then,in
years old, he received two cherished books as 1965,ourideasaboutMarschangeddrastically
Christmas presents. Both were from Random whenMariner4flewbytheRedPlanetandpro-
House, two selections from the “All About” se- ducedasmallsetofgrainypicturesrevealinga
ries. All About Rockets and All About the Uni- dry,crateredsurfacemuchmoreliketheMoon
versewerereadoverandoveragain.Thesebooks than a planet where life might exist.
describethestatusofsolarsystemunderstand- Rapidlythespaceprogramgrewincapability
ing at the start of the 1960’s. The books told and complexity. Now (as of 2009), spacecraft
about a coming age when humans would send havevisitedandstudiedatcloserangeallofthe
spacecraftoutintothesolarsystemtotakepho- planets in our solar system from Mercury to
tographsandmakedirectmeasurementsofthe Neptune, many of their satellites, and several
knownplanetsfromMercurytoPluto,andalso asteroids and comets. More information has
examinetheirmoons.Thebooksforetoldthead- beengainedaboutthesolarsysteminafewde-
venture of trying to unlock the secrets of the cades by robotic explorers and space-based ob-
planetsandofthegreatmissionstocomewhen servatoriesthanhadbeenlearnedfrommillen-
humans would extend their reach from the nia of observations from Earth’s surface, first
Earthtotheplanets,maybeevensendingpeo- withtheunaidedeyeandlaterwithtelescopes.
pletomakediscoveriesoutinspacethemselves. Muchofwhathadbeenbelievedaboutsolarsys-
The book All About the Universe painted a tembodiesandtheprocessesofphysicalevolu-
pictureofbeautyandserenityinboththesolar tionthroughoutthesolarsystemturnedoutto
system and the universe around it. Pretty pic- be wrong. Craters on the Moon were created
x