8 Sept 2003 Solar System - C. C. Lang 1

Surface Exploration of Mars: Past & Future

• Martian Meteorites

• Martian Moons

• Martian Surface ExplorationThe Viking Landers (early 80s)Pathfinder (1997)Current Surface Explorers (three en route!)Future of Martian Exploration (“astrobiology”)

• Review of Mars

8 Sept 2003 Solar System - C. C. Lang 2

What are these “meteorites”?

Martian Meteorites

Why aren’t they orange – the color of Mars surface?

How did they get to Earth?

How do we know these meteorites are from Mars?

Martian datawithout going

there!

Unusual rocks found in Antarctica

An impact on Mars (crater size: 10-100 km) ejectedpart of the Martian surface

Chemical composition does not match usual meteoritesOnly 1.3 billion yrs old (most asteroid-type meteoritesMUCH older); Higher content of volatile substances

Has to do with how the rocks weathered

8 Sept 2003 Solar System - C. C. Lang 3

Case Study: Martian Rock ALH84001

Mass = 1.9 kgIgneous RockDiscovered in Antarctica (easier to find) 1984Formed on Mars 4.5 Billion yr agoEjected ~16 Million yr agoLanded ~13,000 yr ago

What DO they tell us?

What DON’T they tell us?

-Physical processes on MarsCrust/core developed early in Solar System Volcanism until < 1 Billion Years ago

- Chemical compositionDifferent than normal asteroid (meteorite) comp.

Interaction with waterMartian atmosphere composition

- Location of origin (on Mars – which part of surface?)- Enough about Mars’ water & atmosphere- Need to actually RETURN ROCKS from Mars!!

8 Sept 2003 Solar System - C. C. Lang 4

Globules of carbonate minerals (the yellow-orange grains) are scattered along cracks in this small chip of ALH 84001.

The rims contain iron oxides (including magnetite) and iron sulfides--incompatible minerals that on Earth would suggest microbial action

Controversial – microbial presence in meteorites??

Close up views reveal structure similar to Earth microbes?

Astrobiology: exciting field of research – study of origin of life in the solar system,universe- LIFE IS UBIQUITOUS in the universe – we just haven’t found it- LIFE IS A SPECIAL quirk of nature and timing – very very rare!

8 Sept 2003 Solar System - C. C. Lang 5Phobos (20 km x 27 km)Comparison: Asteroid Eros

(33 km x 13 km)

Martian Moons

Deimos

Two moons: Deimos, Phobos

Small (~20km) irregularly shaped

Orbit Mars in 8hr, 30hr

Probably captured asteroids

8 Sept 2003 Solar System - C. C. Lang 6

Risks of Solar System Missions

PROS for Space Missions

Closest views of the planets

that are possible

Access to wavelengths that are unavailable on the ground

Atmospheric effects gone – get clearer views than on Earth

Development of sophisticated tech. and research

CONS for Space Missions

+ Can not fix/test equipment as easily

+ Large risk with rocket launch

+ Much much more costly! (although more costly for manned than unmanned)

+ Lifetime is usually shorter

+ Upgrades much more difficult

+ Risks from UV radiation, cosmic rays

8 Sept 2003 Solar System - C. C. Lang 7

Viking Landers 1 and 2

• Viking 1 launched in August of 1975, Viking 2 launched in Sept. 1975• Vikings arrived at Mars in June, August of 1976• Orbiter + Lander – Orbiters alone weighed close to a ½ ton each –

very expensive launch/rocket equipment !!- these days NASA’s mantra: “Faster Better Cheaper”

8 Sept 2003 Solar System - C. C. Lang 8

Viking Lander Images of Mars’ Surface

• landing site chosen from Orbiter images – two different regions in Northern Lowlands • revealed that the surface of Mars was littered with jagged rocks and fine dust everywhere• rocks were probably result of crater-forming impact (“ejecta”)• rocks resemble lava-rocks on Earth – lava flows broken up by impacts

8 Sept 2003 Solar System - C. C. Lang 9

Viking Landers: Search for Life on Mars

• Science Instruments: - chem lab to explore reactions of Mars rock with water (none detected)

- scoop arm with magnet – found that the soil was IRON-rich

• confined to study only one part of Martian surface – its landing site

• inspired NASA to propose formissions with MOVING surfacevehicles – Pathfinder 1997!

8 Sept 2003 Solar System - C. C. Lang 10

Mars has a very thin atmosphere and no magnetosphere. If humans populated the Martian surface, what environmental problems will they be concerned about?

(1) Global Warming

(2) Solar flare particles and ultraviolet radiation

(3) Nitrogen poisoning

(4) Lead contamination from volcanoes

(5) Magnetic anomalies in the interior causing brain disorders

8 Sept 2003 Solar System - C. C. Lang 11

Mars Pathfinder Mission – landed on Mars 4 July 1997

Demonstration mission for“Faster Better Cheaper” NASA mantra

• used lightweight airbagsto land

• small, efficient roboticvehicle

• 10x as many images asprevious missions (computers)

• landed 500 miles from Vikings – flood plain area(volcanic rocks with silicon)

8 Sept 2003 Solar System - C. C. Lang 12

Panoramic View from Mars’ Pathfinder’s Sojourner Rover

8 Sept 2003 Solar System - C. C. Lang 13

ATHENA: MARS EXPLORATION ROVERSOpportunity & Spirit (or MER A and MER B)

• Launched in June and July of 2003

• arrival at Mars – January 2004

• Each Rover weighs 180 kg, is ~5 ft high

• surface exploration: travels 100m per day

RoverRover

8 Sept 2003 Solar System - C. C. Lang 14

ATHENA: MARS EXPLORATION ROVERATHENA: MARS EXPLORATION ROVER

Mars Rover Entry Sequence

Mars Rover Entry Sequence

8 Sept 2003 Solar System - C. C. Lang 15

cartoon of the “airbag” landing of the Mars Exploration Rovers on surface

8 Sept 2003 Solar System - C. C. Lang 16

Choosing a site to land on Mars

Can not just land anywhere – need to consider the safety of the vessel!- previous missions have landed in the northern lowlands

8 Sept 2003 Solar System - C. C. Lang 17

Mars Landing Considerations

• terrain- altitude (impossible climbs, falls)- slopes (use too much energy)- rockiness (protect airbags)

• solar panel heating – keep rover operable

• dust- solar panels clear- RAT tool works more in thick dust

8 Sept 2003 Solar System - C. C. Lang 18

Science Objectives of the MER mission

• Characterize a variety of rocks and soils that hold clues to past water activity – i.e. try to identify carbonates (indicate water-volcano cycles)

• Distribution and composition of minerals, rocks, and soils near sites

• Determine geologic processes have shaped the local terrain

• Perform "ground truth" – calibration and validation –of surface observations made by Mars orbiter instruments.

8 Sept 2003 Solar System - C. C. Lang 19

Mars Exploration Rover: Science Instruments

Pancam- Stereo camera

IR Spectrometer - rock composition

X-ray Spectrometer - soil and rock chemistry

RAT - rock abrasion tool

Microscopic imager (search for fossils?)

8 Sept 2003 Solar System - C. C. Lang 20

Landing Sites on Mars: 1. Gusev Crater - morphological- 15 degrees South of Mars’ equator- large crater feature with several ‘channels’ leading into it- water may have pooled in crater during first 2 billion years

“channel”

8 Sept 2003 Solar System - C. C. Lang 21

Landing Sites on Mars: 2. Meridiani Planum - mineralogical- 2 degrees South of Mars’ equator- other side of planet from Landing Site 1- place where hematite has been found (rust-like mineral) – indicates that

it is a former dried lake bed

8 Sept 2003 Solar System - C. C. Lang 22

Mars Express – European Effort

8 Sept 2003 Solar System - C. C. Lang 23

MARS EXPRESS

• Launched June 2003

• Radar instrument (MARSIS) built at University of Iowa (Prof. D. Gurnett, P.I.)

• other instruments, including a small rover called “Beagle 2”

8 Sept 2003 Solar System - C. C. Lang 24

MARS EXPRESS: Radar Experiment

• Radar reflection signal of water is very different from rock

• Echoes can differentiate between rock and ice or water

• Radar transmitter operates at 1-2 MHz and penetrates ground to several km depth

• Probably cannot distinguish between CO2 and H20.

8 Sept 2003 Solar System - C. C. Lang 25

8 Sept 2003 Solar System - C. C. Lang 26

Mars Surface Exploration – the Future!

8 Sept 2003 Solar System - C. C. Lang 27

Mars Surface Exploration – the Future!

8 Sept 2003 Solar System - C. C. Lang 28

Future Mars Exploration: “Scout Missions”

• lightweight/efficient ballons • fleet of small aircraft to explore Mars • develop new technology• also SAMPLE RETURNS

8 Sept 2003 Solar System - C. C. Lang 29

Martian Outpost: 2030

8 Sept 2003 Solar System - C. C. Lang 30

8 Sept 2003 Solar System - C. C. Lang 31

This powerpoint was kindly donated to www.worldofteaching.com

http://www.worldofteaching.com is home to over a thousand powerpoints submitted by teachers. This is a completely free site and requires no registration. Please visit and I hope it will help in your teaching.