MARS EDUCATION PROGRAM DavidHardy A. Impact Cratering MARS EDUCATION PROGRAM Meteorites onMars • Craters asdating tools • How docraterscan changeovertime • Different parts ofacrater • Formation ofcraters • cratersinoursolarsystem Impact • meteorites! Causes ofimpacts- • willlearnaboutimpactcraters What we Impact cratering overview: cratering Impact today: MARS EDUCATION PROGRAM Shower Leonid Meteor November 2002 Spain

Juan Carlos Casado MARS EDUCATION PROGRAM Sophie DesRosiers, Planétarium de Montréal Montréal de Planétarium DesRosiers, Sophie planet’s atmosphere. by aobjectfromspace asittravelsthrougha Meteor r“hoigsa”isthevisiblepath made or “shootingstar” MARS EDUCATION PROGRAM StarChild, NASA are neededtoseethispicture. YUV420 codecdecompressor Bill Menke QuickTime™ anda Meteor ormeteorite? .Eichmiller S. Peekskill, NewYork October 9,1992 Peekskill Meteorite through theatmosphere Meteorite breakingup asittravels MARS EDUCATION PROGRAM Dutch Meteor Society Uganda, Africa Boy hitbyameteorite mtood)ta ec a planet’ssurface. (meteoroids) thatreach Meteorites r objectsfromspace are uofReiser Rudolf Namibia, Africa Largest meteorite discovered on Earth R.A. Langheinrich Meteorites Collection Meteorites Langheinrich R.A. Arizona Iron meteorite MARS EDUCATION PROGRAM dust Space NASA/JPL éieEngrand Cécile r atce frc,metal are particlesofrock, What aremeteoroids? and/or ice inspace. Asteroids Meteoroids NASA/JPL Comets planets other Pieces of Rudolf Reiser MARS EDUCATION PROGRAM Don Dixon years ago! 4.5billion the formationofoursolar system Most meteoroidsarematerialsleftoverfrom MARS EDUCATION PROGRAM NASA/JPL Asteroid Belt Ida from? Where domostasteroidscome MARS EDUCATION PROGRAM Max-Planck-Institut furAeronomie Max-Planck-Institut Halley’s comet come from? comets domost Where NASA/JPL MARS EDUCATION PROGRAM Andrew C. Stewart hthappenswhen a large What meteoroid hits aplanet? MARS EDUCATION PROGRAM Why arethey important? Meteor Crater, Arizona Crater, Meteor o ocraters form? How do Impact cratersareformed!

USGS THEMIS Image, Mars

NASA/JPL/ASU MARS EDUCATION PROGRAM Earth’s Moon NASA/JPL MARS EDUCATION PROGRAM Mercury NASA/JPL MARS EDUCATION PROGRAM OAtopographic map MOLA Mars NASA/JPL MARS EDUCATION PROGRAM Mimas, moonofSaturn Crater Herschel giant impacts! Evidence of NASA/JPL MARS EDUCATION PROGRAM Sophie DesRosiers, Planétarium de Montréal Montréal de Planétarium DesRosiers, Sophie r hr impactcratersonEarth? Are there MARS EDUCATION PROGRAM

David McKinnon etr utai,Australia Western Australia, Wolf CreekImpactCrater

Google Earth India Lonar ImpactCrater N Impact CratersonEarth Ronald W. Hayes, USGS Quebec, Canada Manicouagan ImpactCrater MARS EDUCATION PROGRAM Holsinger meteorite (1400lbs) Best preservedimpactcrater

Geoscience Research Institute on Earth! Impact 50,000 yearsago Winslow, Arizona Meteor Crater atnHellman Martin MARS EDUCATION PROGRAM AA/LI/VL Sharpton / LPI / NASA V.L. Gravitational anomaly map Impact 65millionyears ago Yucatán Peninsula Chicxulub impact crater Sophie DesRosiers, Planétarium de Montréal Montréal de Planétarium DesRosiers, Sophie MARS EDUCATION PROGRAM

Lunar and Planetary Institute MARS EDUCATION PROGRAM How doimpactcratersform? Flagstaff, Arizona Cinder Lakes Meteorites impact on Mars!

MARS EDUCATION PROGRAM

Contact - Compression Sophie DesRosiers, Planétarium de Montréal Montréal de Planétarium DesRosiers, Sophie Shock waves Planet surface Ejecta Meteoroid Planet surface Crater Formation: 2. Shockwaves compressthe .Meteoroidtraveling10-15 1. meteoroid isvaporized rocky surface andthe the surfaceofaplanet kilometers/second strikes MARS EDUCATION PROGRAM

Excavation Sophie DesRosiers, Planétarium de Montréal Montréal de Planétarium DesRosiers, Sophie Shock waves Shock waves Planet surface Ejecta Vapor Crater Formation: Crater Ejecta curtain Molten rock .Crater isformedasshock 4. 3. Intenseshockwaves travel rock up andmeltingsurrounding through theground,breaking outward waves and ejecta expand MARS EDUCATION PROGRAM

Modification Ejecta blanket Sophie DesRosiers, Planétarium de Montréal Montréal de Planétarium DesRosiers, Sophie Fractured rock Fractured rock Fractured rock Breccia Crater Formation: Ejecta rim Uplifted 5. Shock waves die outand die 5. Shockwaves .Cae sflyfre n is 6. Crateris fullyformedand rim blanket aroundthecrater ejecta settlesforming a geologic time. and sedimentation over gravity, erosion modified by MARS EDUCATION PROGRAM surface crust

NA SA/JPL/ASU Satellite View ej Impact cratermorphology: crater onMars Visible THEMIS Image impact ieVe faCrater Side Viewof a w cp f r debris canfalltothefloor Wall (w) or getupliftedduringtheimpact or can rebound ofthecrater thefloor craters, Central Peak(cp) collect debrisfrom thesides ofthecrater Floor (f) htgt honotdrn impact that getsthrown out during Ejecta (ej) surface Rim (r) : where rock is foldedaboveoriginal : whererock : the bottom of the crater whichcan the bottomofthecrater : : the steepest part, whereloose the steepestpart, : : materialfrominside the crater : visibleinmostlylarge MARS EDUCATION PROGRAM MOLA map Mars Where dowefindcraterson Mars? 2,100 kilometer diameter crater insolarsystem! Largest Hellas Planitia NASA/JPL MARS EDUCATION PROGRAM Craters uniquetoMars:Rampart itraCae,Mars Victoria Crater, (“splosh”) craters NASA/JPL Mars Tooting Crater, ejecta Lobate MARS EDUCATION PROGRAM August 2004 August Opportunity’s Landingsite Mars Exploration Rover Endurance Crater,Mars

NASA/JPL

N

A

S

A

/

J

P

L NASA/JPL MARS EDUCATION PROGRAM

THEMIS images

N

A

S

A

/

J

P

L

/

A

S

U Craters arewindowsintoaplanet’s

N

A

S

A

/

J

P

L geologic past

N

A

S

A

/

J

P

L

/

A

S

U of craterduring impact). impact breccia Victoria Crater; notethe layersof Opportunity examinedtherim of MarsExplorationRover NASA's NASA/JPL-Caltech/Cornell/U.S. GeologicalSurvey scientists tostudy for rock layers Craters expose (fragments thrownout HiRISE mosaic MARS EDUCATION PROGRAM Lonar Crater,India • Covered orfilledin Covered • Eroded • tectonism, andvolcanism) ejecta) and landslides, lava, vegetation, sediments, How areimpactcratersmodified (wind, water, on EarthandMars? (water, Victoria Crater, Mars matcrater,Mars Impact

N Tiku Ravat

A

S

A

/

J

P

L MARS EDUCATION PROGRAM HMS1N,70E THEMIS Wind streaks Martian craters:Modificationbywind HMS44N,38.3E THEMIS

NA SA/JPL/ASU Sand dunes (dark areas) HMS19N,284.9E THEMIS

NASA/JPL/ASU Yardangs (ridges)

NA SA/JPL/ASU MARS EDUCATION PROGRAM HMS43.6N, 296.4E THEMIS sediments deposition of Channels and Martian craters:Modificationbywater sediments

NAS A/JPL/ASU HMS16N,329.6E THEMIS Islands Streamlined HMS36.3N, 292.8E THEMIS NASA/JPL/ASU Gullies

NA SA/JPL/ASU MARS EDUCATION PROGRAM THEMIS 12.6N, THEMIS 83.8E ata rtr: oiiainb gravity Martian craters:Modificationby Slumps (slumping andlandslides)

NASA/JPL/ASU THEMIS 0N, THEMIS 313.4E rim crater Landslides

NASA/JPL/ASU MARS EDUCATION PROGRAM THEMIS 0N, 0E .Cross-cuttingrelationships 1. feature cutisolderthan whatcutit.” Using cratersasdatingtools

NASA/JPL/ASU THEMIS 29.7N, 1.7E -“The

NASA/JPL/ASU 288E THEMIS -54N, 3 2 1

NASA/JPL/ASU MARS EDUCATION PROGRAM THEMIS 14.1N, THEMIS 287.9E .Crateringrate 2. h le the surface. the older there areona surface, craters Using cratersasdatingtools

NASA/JPL/ASU THEMIS 36.8N, THEMIS 42.7E Which issurface themore - is older?

NAS A/JPL/ASU 0N 70N 70S 0E

N

A

S

A

/

J

P

L MARS EDUCATION PROGRAM .Cratermodification 3. HMS69.1N, 273.6E THEMIS modified acrater,the older itis. Using cratersasdatingtools

NA SA/JPL/ASU generally, themore - craters appear older? Which HMS44N, 38.3E THEMIS

NASA/JPL/ASU MARS EDUCATION PROGRAM Preserved Determining theageofacrater Modified

Destroyed no modification Well definedcraterwith littleto and ejecta are stillvisible floor, centralpeak,rim, walls, Partially modifiedcrater, but etrsdifficult tosee features covered crater; Mostly eroded or NASA/JPL/ASU MARS EDUCATION PROGRAM r hr eertso Mars? Are theremeteoriteson NASA/JPL

N

A

S

A

/

J

P

L Iron meteorite found on Mars! By Mars Exploration Rover Opportunity in January 2005

“Heat Shield Rock” NASA/JPL MARS EDUCATION PROGRAM Impact cratershelp usunderstand: h motneo mat nplanetary The importanceofimpacts in • geologicprocesses workon How • The geologichistory andageofa • formation andevolution different worlds,and planet’s surface