Life In The Universe Unit 3

Front 1

Problems for life on small moons, comets and asteroids

Back 1

a.Small size rules out atmosphere and liquid oceans.
b.No internal source of energy

Front 2

Mechanisms for exploring other worlds

Back 2

a.Telescopic observation
b.Robotic exploration
c.Human exploration of worlds.

Front 3

Flyby vs. Orbitor

Back 3

a.Flyby-Spacecraft goes by world just once and then flies through space. Cheaper than orbiter but you don’t get as much information.
b.Stays in orbit around world of interest. More expensive but more data collected.

Front 4

Landers and probes

Back 4

a.Enter atmosphere and possibly land on surface and send out a rover.
b.Probes look at atmosphere.

Front 5

Sample return mission

Back 5

a.Returns to earth after exploring another world, bringing back material for study.
b.Have been to the moon and a comet.

Front 6

Why is Mars Interesting to us

Back 6

•Posibility of life
•Past water flow on the surface.
•Early environment similar to earth’s

Front 7

Herschel Sibilings

Back 7

Observed icecaps, length of days.

Claimed to see and atmosphere.

Said there were inhabitants probably like ours.

Front 8

Giovanni Schiaparelli

Back 8

Saw linear features he called canals or channels.

Spawned idea of artificial water way.

Front 9

Percival Lowe

Back 9

Built Lowe observatory in Flagstaff.

Mapped out canals on Mars.

Idea discounted by Alfred Russel Wallace.

Front 10

Alfred Russell Wallace

Back 10

Discounted Percival Lowe’s idea.

Mars is too cold for liquid water.

Caps must be dry ice.

Canals should follow the counters of the land.

Front 11

Features Of Mars's Surface

Back 11

•No Plants or animals.
•Evidence of water flow
•Nothing grew but frost.
•Nothing moved but dust.

Front 12

Mars's Atmosphere

Back 12

•1/100th of Earths
•Pressure to low for liquid water
•95% co2

Front 13

Mars's temperature

Back 13

•-133-70 degrees Fahrenheit

Front 14

Lenth Of Mars's Days

Back 14

24 hrs 37 minutes

Front 15

Mars's Seasons

Back 15

A more Elliptical orbit makes seasons different then on earth

Front 16

Mars's Surface Water

Back 16

No surface liquid that we have found

Front 17

Mars's Tectonic plates

Back 17

• Meteorite dating say that Mars is still geologically active today while Craters and volcanoes say it is not.

Front 18

Mars's Volcanic Features

Back 18

Largest volcano in the solar system is Olympus Mons

No active volcanic activity

Front 19

Evidence of Past Surface Water on Mars

Back 19

River drainage systems

Craters show evidence of erosion and of recent water flow.

Flood channels flow north towards “oceans”

Blueberries

Layering suggests wave action

Front 20

Water on Mars today

Back 20

Under the surface.

Front 21

Atmospheric changes on Mars

Back 21

More co2

Co2 may have been lost from impacts

Co2 may have been lost from solar wind stripping.

Front 22

Co2 and water vapor loss from an atmosphere

Back 22

Water and co2 can be lost from impacts and solar wind stripping.

Water also could have been broken aprt by ultra violet light.

Front 23

Viking Experiment Conclusion

Back 23

No life could be found.

Front 24

Evidence of life from orbiters and landers

Back 24

Methane in the atmosphere

Front 25

How did meteors from Mars get to Earth

Back 25

Blown of Mars during massive collisions.

Front 26

Evidence of Life on Mars from ALH84001

Back 26

Alternating forms of minerals that do not form together

Contain PAH’s which are associated with decay of dead organisms.

Magnetite grain look like they were made from bacteria.

Rod shaped structures look like bacteria on a small scale.

Front 27

Alternate explanations for ALH84001

Back 27

Pulses of hot water could have made mineral layers.

PAH’s could have been created chemically

Could have been contaminated during handeling.

Things could have happened while sitting in the ice.

Front 28

ALH84001 and our view on origin of life

Back 28

Reminds us that life could be carried in from elsewhere in the solar system.

Front 29

Current mars exploration

Back 29

Mars odyssey (orbiter

Mars express (orbiter)

MER-A spirit (Rover)

MER-B opportunity (Rover)

Mars reconnaissance (orbiter)

Front 30

Contamination with exploration

Back 30

a. We could bring life to mars.
b. Life on mars could be brought back and might be harmful to us.

Front 31

Terraforming

Back 31

Changing a planet to make it more earth-like.

Is the planet really ours to change?

Front 32

Large moon formation

Back 32

Same way as the solar system. Solar nebula on a smaller scale.

Like in the solar system, moons closer to Jupiter are rock, farther are more ice.

Front 33

synchronous rotation

Back 33

Keep the same face to the planet at all times.

Front 34

Tidal forces and Heat on a moon

Back 34

Elliptical orbits cause stretch and bulge in the matter of the moon, causing friction which produces heat.

Front 35

Evidence of Liquid ocean on Europa

Back 35

Few craters means young surface.

Chaotic terrain resembles artic ice pack.

Tidal heating is sufficient to keep most heat melted.

Magnetic field evidence shows flow of current in something that contains electricity. Maybe salt water.

Front 36

Determinants for elements and molecules

Back 36

Elements=everywhere

Molecules= Need atmospheres or oceans

Front 37

Sources of energy

Back 37

Sunlight=Used if there is enough

Internal heat= used if sunlight is not enough

Front 38

Limitations of being far from a star

Back 38

Need larger surface area.

Need to be more sufficient at collecting solar energy

Need much slower reproduction or metabolism

Front 39

Why atmosphere and oceans are so essential

Back 39

Atmosphere can mix gases for chemical energy.

Water serves as a medium to mix materials for chemical energy.

Front 40

Why water is superior

Back 40

Dissolves molecules making them ready for chemical reactions in a cell.

Transports chemicals into and out of a cell.

Involved directly in metabolic reactions.

Remains liquid over large temperature range.

Expands/floats when frozen.

Polar molecule

Temperature Regulation

Surface tension

Shield against UV

Front 41

Other solvents for life

Back 41

Ammonia

Methane

Ethane

Front 42

Environmental requirements for life

Back 42

Source of elements and molecules that build living cells

A source of energy for metabolism.

A liquid medium for transporting the molecules of life.

Front 43

Why life isn't present on the moon and mercury

Back 43

Surface temperatures extreme.

No atmosphere

No liquid water

No internal heat source.

Front 44

Why life isn't present on Venus

Back 44

Dense atmosphere

No liquid water

High surface temperature

Front 45

Why life could and couldn't be present on Jupiter and Saturn

Back 45

Having life
1.Atmosphere
2.Energy available
3.Necessary chemistry should exist
4.Probably an liquid water at some layer.

Not having Life

1.Extreme turbulence in atmosphere.