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MARSSTUDENT IMAGING

PROJECT

Resource Manual

Mars Education ProgramJet Propulsion LaboratoryArizona State University

Version 2.00

The Mars Student Imaging Project

Written and Developed by:

Keith Watt, M.A., M.S.Assistant Director

ASU Mars Education Program

Image Processing Curriculum by:Sara Watt, M.S.


Editing by:

Paige Valderrama, M.A.Assistant Director


Sheri Klug, M.S.Director


(C) 2002 ASU Mars Education Program. All rights re-served. This document may be freely distrubuted for non-commerical use only.

MARS STUDENT IMAGING PROJECT RESOURCE MANUAL1

with the theory, however. Careful ob-servations showed that the planets didnot quite move in perfect circles.Faced with an observation that couldn’tbe explained with current theories,Ptolemy modified Eudoxus’ theory andreplaced his simple circles with a com-plicated system of “epicycles”, circlesthat interlock like gears in a complexmachine. Ptolemy’s theory could de-scribe and predict the motions of theplanets with an accuracy never beforeachieved. For almost 1,400 years,until the 16th century, Ptolemy’stheory was considered to be the onlycorrect theory of the Universe. Thetheory was endorsed by the CatholicChurch, which declared any other ex-planation for the planets’ motions tobe heresy and punishable by death.

Ptolemy’s theory only had one prob-lem: it was wrong. One hundred yearsafter Eudoxus, the astronomerAristarchus watched the shadow of theEarth sweep across the surface of theMoon during a lunar eclipse. His ob-servations showed that the Sun hadto be much larger than the Earth, andhe felt that it was not likely that a large

In the BeginningScience and our view of the worldchange only when we are presentedwith some observation we can’t ex-plain. Early Greek scientist-philoso-phers believed that Earth was at thecenter of the Universe and all othercelestial bodies revolved around it.Eudoxus, a mathematician who livedin the fourth century B.C., was one ofthe first people to propose this theory.Eudoxus’ version of the theory was el-egantly simple: God is perfect, theonly perfect forms are circles, there-fore the Sun and planets must movein circles around the Earth. ClaudiusPtolemy, a Greek scholar who lived inAlexandria, Egypt, around 140 ADnoted that there were some problems

Chapter 1: Mars in Society and Culture

Mars has always played a significant role in human society. The early Greeksnoted that unlike the other planets, Mars sometimes seemed to reverse itsdirection across the sky. This “contrary” motion suggested disorder and anar-chy to the Greeks, which, along with its reddish color, led them to name theplanet after Ares, their god of war. The Romans later changed the planet’sname to that of their god of war, Mars, and the name has remained ever since.

The Ptolemaic UniverseCredit: University of Tennessee


Sun would rotate around the smallerEarth. He proposed instead that theEarth revolves around the Sun. Hewas condemned for heresy because ofhis theory and all of his writings wererounded up and destroyed. The onlyreason we know anything aboutAristarchus at all is because he is men-tioned in the writings of the greatmathematician Archimedes. No otherscientist was willing to risk the wrathof the Church by mentioning theastronomer’s work. In 1543, nearly2,000 years later, however,Aristarchus’ theory was taken up byPolish doctor, lawyer, and part-time as-tronomer Nicolaus Copernicus.Copernicus’ careful observations couldnot be explained by Ptolemy’s theory.Only if the Sun were at the center ofthe Solar System could his data makesense. Once again, because of newobservations, new science and a newworldview was born.

The New ScientistsMars played a major role in the con-troversy. Even Copernicus’ theorycould not explain the strange motionsof Mars. In 1600 Tycho Brahe had un-dertaken the careful study of Mars’ or-bit. Tycho was perhaps the greatestobservational astronomer the worldhas ever known. We can make moreaccurate observations today only be-cause we have more accurate instru-ments. Tycho was world famous, arock star of science who toured thepalaces of kings and other nobility allover Europe. Tycho had given his stu-dent, a German mathematician named

Johannes Kepler, the task of creatinga mathematical description of Mars’ or-bit. Tycho, however, was very protec-

tive of his data,

Johannes Kepler (1571-1630)Credit: University of St Andrews, Scotland

the table. When Tycho finally died sev-eral years later, Kepler broke intoTycho’s safe and stole all of his data.Tycho’s family demanded the docu-ments be returned, and Kepler did so– but only after he had made exactcopies of all of the precious data.Kepler, like most of his fellow scien-tists, felt certain that the planets trav-eled in perfect circles. After years ofstruggling with Tycho’s observations ofMars, however, he finally reached theinescapable conclusion that all thework done before him was wrong: theplanets move in ellipses, not circles.In addition, he discovered two otherlaws of planetary motion that he pub-lished in 1609. Thanks to Mars, wenow understood not only its motion,but the motion of the entire Solar Sys-tem as well.

In 1634, Kepler published a book calledThe Dream, in which he described afanciful flight from the Earth to the

as are many sci-entists today.He would throwout an observa-tion over dinnerin casual con-versation, whichKepler wouldf r a n t i c a l l yscrawl down in anotebook thathe kept under


Moon. It was one of the first works ofscience fiction. Science fiction bookshave spurred generations of people towonder about the stars and the plan-ets that travel through the heavens.By the end of the 19th century, how-ever, improved telescopes showed thatthe Moon was a barren, desolate place,a place where no life could possiblyexist. Mars, however, was still a fuzzydisk in even the best telescopes. Sci-ence fiction authors, scientists, and theimaginations of the general publicturned away from the Moon and lookedinstead to the Red Planet. In 1877,Italian astronomer GiovanniSchiaparelli observed a series of linesthat seemed to cross most of the sur-face of Mars. In his notes, he calledthese lines canali, an Italian word thatmeans “channels”. American amateurastronomer Percival Lowell, however,translated the word as “canals”, a verysimilar meaning, but one that has verydifferent implications: “canals” impliesintelligence. Lowell believed thatSchiaparelli had discovered the engi-neering works of a dying Martian so-ciety desperately trying to bring wa-

ter from theMartian icecapsto the equatoriallands. Lowellwas so excitedby the discoverythat he had astate-of-the-arto b s e r v a t o r ybuilt in Flag-staff, AZ, spe-

cifically to study Mars. His writingsignited the imagination of generationsof people around the world, includinggreat science fiction authors such asEdgar Rice Burroughs (the Barsoomseries of 11 novels), Ray Bradbury(The Martian Chronicles), and H.G.Wells (The War of the Worlds). Wells’work was made even more popularwhen Orson Welles (no relation to H.G.Wells) and his Mercury Theater on theAir performed the most famous radioplay in American history. To celebrateHalloween of 1938, Welles adaptedThe War of Worlds, a tale of a Martianinvasion of the Earth, into a radiobroadcast. Story events were pre-sented as “news broadcasts” report-ing New York City in flames and un-stoppable aliens destroying everythingin their paths. Millions of people, whotuned in to the play late, thought thebroadcasts were real and fled theirhomes in terror of the “invasion”. Mosthad taken to the streets in panic andnever heard the play’s end and Welles’wish for them to have a happy Hal-loween. NBC issued a public apologythe next day; Welles became one ofHollywood’s most successful actors.Mars, and the possibility of life there,was so firmly ingrained in the mindsof the public that no one questionedthat the events of that night might nothave actually been real. Mars has al-ways had this power over us.

Today scientists know that Mars in itscurrent form probably cannot supportlife as we know it. Spacecraft sent toLowell’s drawing of Mars

Credit: The Wanderer Project


Mars have found no trace of Lowell’s“canals” or of his dying civilization. Butwas Mars always as it is now? Datareturned from our Mars spacecraftshow us that it almost certainly wasnot. At some time in the past, Marswas much warmer and wetter than itis today. What happened to Mars? Did

it once have life? Where did all thewater on Mars go? Could Earth alsochange as Mars has? These are just afew of the questions scientists hopeto answer, important questions thatyou will also help to answer as youbegin your exploration in the Mars Stu-dent Imaging Project.

The Inner Solar SystemCredit: Keith Watt


The Mars RaceOn October 4, 1957, the Soviet Unionlaunched Sputnik 1, the first man-made object into space. In doing so,they did more than launch a space-craft, they launched a race that wouldultimately end with the United Stateslanding a total of 12 astronauts on thesurface of the Moon. While manypeople are familiar with the MoonRace, not many people realize thatthere was a “Mars Race” as well. In1960, the Soviet Union attempted tolaunch two robotic space probes toMars. Both exploded at launch. In

1962, however,they successfullylaunched theirMars 1 probe andput it on coursefor the RedPlanet. Allseemed to be go-ing well until thespacecraft wasabout halfway toMars. Suddenly,all contact with

Chapter 2: Mars Exploration Background

As mentioned in Chapter 1, Mars has attracted the attention and imaginationsof observers for thousands of years. The first serious observations of the Mar-tian surface were conducted by Schiaparelli in 1877, whose work was expandedupon by Lowell in 1890. Until the dawn of the space age in the early 1960’s,telescopic observations were the only way we could study Mars. Even the besttelescopes, however, must still look up through the Earth’s atmosphere in orderto see out into space. It’s a lot like trying to watch clouds from the bottom of aswimming pool: the objects are there, but they are fuzzy, wavering, and hardto make out. If we want to conduct serious observations of another planet, weneed to go there.

the probe was lost. No one has everdetermined what happened to theprobe, but its loss gave the Americanteam another chance to be the first toMars.

Thrilled with the success of Mariner 2,the first unmanned mission to Venus,NASA began its program of Mars ex-ploration, hoping to be the first coun-try to explore Mars as well. Approxi-mately every two years the planets arein just the right position for an Earth-Mars trip that requires the leastamount of fuel. In 1964, NASA pre-pared to launch Mariner 3 and Mari-

SputnikCredit: NASA

Mariner 4Credit: NASA/JPL


ner 4 to Mars. During the launch ofMariner 3, the spacecraft’s protectivelaunch shroud collapsed, destroyingthe spacecraft. With only three weeksremaining in the low-fuel launch win-dow, NASA engineers scrambled to getMariner 4 ready to take the place ofits sister spacecraft. On November 28,1964, Mariner 4 launched successfullyand put onto the path to Mars. TheSoviet Union was not far behind, how-ever. Two days later, on November30, they launched Zond 2 and put iton course to Mars as well. There wasnow a literal race to the Red Planet.Two spacecraft were headed to Mars.Which would get there first?

The race stayed close for the firstmonths of the trip, but just as Zond 2reached the point near where Mars 1vanished, it too lost all communica-tions. NASA engineers joked about a“Great Galactic Ghoul” that ate Marsspacecraft. They stopped laughingwhen Mariner 4 began having commu-nications difficulties in the same area.Unlike Zond 2, however, Mariner 4 re-

solved its difficulties and sailed on toMars. On July 15, 1965, Mariner 4became the first spacecraft to visitMars. The spacecraft returned 21 im-ages that revealed the dry, crateredsurface of Mars. Dreams of a gardenplanet were laid to rest forever, butthe data showed that Mars was a fas-cinating planet in its own right.

Missions to Mars continued with Mari-ner 6 and Mariner 7 in 1969, both per-forming flyby missions similar to Mari-ner 4. Mariner 6 performed flawlessly,but Mariner 7, during its mission, sud-denly lost contact with Earth. Engi-neers were afraid the “ghoul” had re-turned, but they managed to re-es-tablish contact and determined that abattery on board had exploded duringthe pass behind the planet. The con-trollers instructed Mariner 7 to shutdown its damaged systems and con-tinue the mission. The two spacecrafttogether returned 58 pictures of theMartian surface taken from a distancehalf as far from the planet as Mariner4. The images, and particularly thosefrom Mariner 7’s flight over the Mar-tian polar caps, once again changedthe way we view Mars. Mariner 7 car-ried an infrared spectrometer on boardthat was able to analyze the composi-tion of the ice. The spacecraft discov-ered that the south polar cap of Marsis not water ice at all, but is insteadcomposed almost entirely of frozencarbon dioxide, or “dry ice”.

ZondCredit: Lunar and Planetary Institute


Mariner 9NASA engineers quickly realized thatin order to carefully study a planet,you have to not only go there, youhave to stay. What was needed was aspacecraft that would travel to Marsand place itself in orbit around theplanet. The United States was notalone in this assessment. The SovietUnion designed three spacecraft thatwould travel to Mars during the nextlaunch window. In 1971 they were tojoin the American Mariner 8 and Mari-ner 9 probes on the long journey tothe Red Planet. The Soviets, however,were attempting to leapfrog the UnitedStates: each of their spacecraft con-tained not only an orbiter, but also alander designed to descend and sendback the first pictures from the sur-face of Mars. The American Mariner 8spacecraft died when the second stageof its Atlas-Centaur booster rocketfailed to ignite. The Soviet Cosmos419 made it into space, but never leftEarth orbit because the ignition timerfor its last stage had been mistakenlyset for 1.5 years rather than 1.5 hours

after launch. The fleet of spacecraftheaded to Mars had been reduced fromfive to three in just a few weeks.

The three remaining craft, the SovietMars 2 and Mars 3 and the AmericanMariner 9, were all launched in May of1971. Once again, the race to Marswas on. The race was won by Mariner9, which was on a slightly faster coursethan its Soviet counterparts. On No-vember 14, 1971, Mariner 9 becamethe first artificial satellite of anotherplanet. Mars 2 arrived two weeks laterand Mars 3 shortly after that. Unfor-tunately, when the three spacecraft ar-rived at Mars, there was nothing muchto see. In September of 1971 a duststorm, visible from Earth, began whicheventually covered the entire planet.Nothing of this scale had ever beenobserved on any planetary body. TheSoviet Mars 2 dispatched its landeranyway, as it programmed to do, butthe lander crashed on the surface,sending back no data. Mars 3’s landerfaired a bit better, sending back a fewseconds of data before it was blownover and destroyed by the raging Mar-tian winds. Still, the Soviet Union hadbecome the first nation to land aspacecraft on another planet – even ifit didn’t do much once it got there.The Soviet orbiters snapped feature-less pictures of the dust-enshroudedplanet until their batteries died. Noth-ing could be seen through the dust onany of the images. Mariner 9, how-ever, had been designed with an on-board computer that could be repro-Mariner image of cratered area on Mars

Credit: NASA


grammed from Earth. NASA control-lers instructed the spacecraft to shutitself down and conserve power untilthe storm passed. By December of1971, the storm was over and NASAwoke up the sleeping spacecraft, whichreturned the highest resolution pic-tures of Mars that had ever been ob-tained.

Once again, new observations com-pletely changed everything we thoughtwe once knew. Observations of Marsby previous spacecraft had led us tobelieve the surface of Mars was acratered, dead landscape, not muchdifferent from Mercury or the Moon.All of those spacecraft, however, hadflown past only the southern hemi-sphere of Mars. The northern hemi-sphere of Mars is made up of smoothplains and lava basins, totally unlikethe cratered south. Mariner 9 alsosolved the mystery of the “seasonalvariations” Mars seems to display.These dark areas on the surface seemto change location with the seasonsand were thought to be indications ofplant life growing during the warmerMartian summers. Mariner 9 foundthat the dark areas were just hugeareas of dark rock exposed when thebright red Martian dust was blownaway by surface winds. As the sea-sons changed, so did the direction ofthe winds, uncovering new dark re-gions. The three previous Marinerspacecraft sent to Mars had shown noindication of volcanic activity. Mari-ner 9 discovered Olympus Mons, thelargest volcano in the Solar System,

and the three Tharsis Montes volca-noes, each larger than any volcano onEarth. The spacecraft also discoveredValles Marineris, the largest canyonsystem in the Solar System, formedwhen some cataclysmic event causedthe crust of Mars to bulge so much itcracked. The canyon is so huge, ifplaced on the Earth it would extendfrom San Francisco to Washington,D.C. The entire Grand Canyon wouldfit in one of its side canyons. Mostsignificantly, Mariner 9 discovered longchannels that look unmistakably likedry riverbeds – indicating that Marsmay have once had liquid water. Theseand other wonders were returned toEarth in the 7,329 images sent backto Earth during the course of Mariner9’s year-long mission. The spacecraftran out of fuel on October 27, 1972,and went forever silent.

The Viking MissionsNASA missed the next launch windowin 1973 because it was preparing foran even more ambitious mission: alarge-scale lander that would carry a

Viking orbiterCredit: NASA/JPL


complete laboratory to the surface ofMars. The Soviet Union was not idle,however, using the 1973 launch op-portunity to send four spacecraft to theRed Planet. None were successful. By1975, the American Viking 1 and Vi-king 2 spacecraft were launched andheaded to Mars. Like their Sovietcounterparts, each Viking spacecraftcarried both an orbiter and a lander.The landers carried no less than 14different experiments, most of whichwere designed to detect life on the sur-face. The trouble was that no two sci-entists agreed upon a definition of life,much less the means to test for it.Both landers touched down safely, Vi-king 1 on July 20, 1976, and Viking 2on September 3, 1976. The landersimmediately began the tests for lifethat were finally worked out as thebest that could be done. The experi-ments initially caused great excite-ment when they indicated they mighthave actually found biological activityin the Martian soil. Later analysis ofthe results, however, indicated that theexcitement was misplaced. Today,most scientists believe that the Viking

experiments did not in fact detect lifeon Mars. The question still remains,however: even if there is no life onMars now, did life ever exist there inits past? The question is still unan-swered.

With the end of the Apollo lunar pro-gram, NASA’s shrinking budget forcedit to concentrate on the Shuttle Trans-portation System, better known as theSpace Shuttle. As a result no Ameri-can spacecraft visited Mars for nearlytwenty years. The Soviet Union (whichwould simply become Russia the fol-lowing year) launched Phobos 1 and 2in 1988 to study the moons of Mars,but the “Great Galactic Ghoul” struckonce again: Phobos 1 was lost en routeto Mars just one month after launch.Phobos 2 arrived near Mars and man-aged to perform, among other things,important studies of the solar windnear Mars before a computer failurecaused controllers to lose contact withthe spacecraft just before reaching itsdestination. Neither mission wascounted as a success.

Viking landerCredit: NASA

Mockup of PhobosCredit: High Energy Astrophysics Science Archive Research Center


In 1992, the United States decided toreturn to the Red Planet and renew itsstudies of this fascinating world. Aswith the Russian spacecraft, Mars Ob-server lost contact with Earth a yearlater just as it was about to enter or-bit around Mars. The Mars Observermission cost nearly one billion dollars.It would be the last of the “old-style”planetary explorers.

Faster, Better, CheaperUnder the leadership of its new ad-ministrator, industrialist Dan Goldin,NASA decided to try a new approachdubbed “faster, better, cheaper”. Theidea was to use many, smaller space-craft, instead of one huge expensivespacecraft. In this way, the loss ofone craft would not doom an entireexploratory mission. The first in thisseries of “Discovery missions” wasMars Pathfinder. In contrast to thebillion-dollar Mars Observer mission,Pathfinder was designed, built andlaunched for only 250 million dollars,one-fourth the cost of Observer. LikeViking, Pathfinder included a lander,

but it also included something neverbefore attempted: an independentrover, named Sojourner, capable oftraveling up to ten meters (32 feet)away from the lander. The missiontested a number of new technologies.Instead of using a Viking-styleretrorocket, the Pathfinder lander wasencased in four large six-chamberedair bags. Upon entering the Martianatmosphere, the lander parachutedmost of the way to the surface, thendeployed and inflated its air bags forlanding. The spacecraft bounced 15to 20 times, sometimes as high as 50feet. The landing went exactly asplanned. On July 4, 1997, Pathfinderopened its landing petals, and beganits science mission while sending theSojourner rover on its way. The mis-sion was a complete success. Thelander returned over 16,500 images,some in 3D. The rover returned over550 images but, more importantly,sent back over 15 chemical analysesof rocks and soil, as well as data onMartian winds and weather. On Sep-tember 27, 1997, the Pathfinderlander, now called Sagan MemorialStation, failed to answer a routine sta-tus check. Controllers tried for sev-eral months to reach the silent craft,but finally gave up on March 10, 1998,officially ending one of the most suc-cessful Mars missions in history.

Although launched a month earlierthan Mars Pathfinder, an orbiter calledMars Global Surveyor actually arrivedat Mars after Pathfinder. Mars GlobalSurveyor was designed to use a tech-Pathfinder Lander and Rover

Credit: NASA/JPL


nique called “aerobraking”, in whichthe spacecraft dips into the Martian at-mosphere to slow down and place it-self in Mars orbit. Aerobraking is adelicate maneuver. If the spacecraftenters too low into the atmosphere, itwill burn up. The spacecraft spent al-most a year and half slowly modifyingits orbit around Mars until it was in anearly circular polar orbit. This orbitwould allow Global Surveyor to imagevirtually the entire planet during thecourse of its two-year science mission,which began in March of 1999. LikePathfinder, Global Surveyor has beena phenomenal success, returning moredata about the Martian surface and at-mosphere than all previous Mars mis-sions combined. The spacecraft car-ried not only a camera (the Mars Or-biter Camera, or MOC), it also carriedan infrared spectrometer (the ThermalEmission Spectrometer, or TES) de-signed to search for minerals and mea-sure the temperature of Mars, as wella laser altimeter (the Mars Orbiter La-ser Altimeter, or MOLA) which providedthe first accurate measurement of the

topography – terrain heights – of Mars.The spacecraft completed its primarymapping mission on January 31, 2001,but was in such good health, missionmanagers decided to extend the mis-sion and to continue gathering data.It was fortunate that they did so, ason June 15, 2001, Global Surveyorscientists detected the beginnings ofwhat would become the largest globaldust storm since the Mariner 9 mis-sion almost exactly thirty years prior.

Flush from the successes of Mars Path-finder and Global Surveyor, NASA com-missioned two more spacecraft for the1998-99 launch window. Mars ClimateOrbiter was to function as a Martianweather satellite and as a communi-cations relay satellite for the othercraft, Mars Polar Lander. Polar Landerwas to land near the south polar icecap of Mars and dig under the surfacein search of water ice. It also carriedtwo “penetrators”, called Deep Space2 (Deep Space 1 was a probe designedto study comets using an experimen-tal ion propulsion unit). Unfortunately,

Mars Global SurveyorCredit: NASA/JPL

Mars Polar LanderCredit: NASA/JPL


Climate Orbiter suffered from human-caused failure, similar to that whichstruck the Soviet Cosmos 419 in 1971.Navigation parameters were fed to thespacecraft in English units, when theprogram was designed to use metricunits. The spacecraft disappeared be-hind Mars on September 23, 1999, andnever reappeared. The fate of PolarLander is still unknown. The space-craft seemed to be functioning nor-mally as it entered the Martian atmo-sphere, but no signal from the surfacewas ever received. Theories includethat Polar Lander burned up on entry,crashed into the surface, or perhaps

it simply landed in rough terrain andwas unable to point its antenna atEarth. This last theory is particularlyironic: the spacecraft could have beencompletely healthy, it just neededsomeone to kick it back upright.Strangely, though, nothing was heardfrom the Deep Space 2 penetrators ei-ther, even though they were deployedearly in Polar Lander’s descent. Wemay never know what happened toMars Polar Lander – at least not untilwe are able to go there and look atthe crash site ourselves.

Mars Global Surface MapCredit: NASA

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