1. Life on Other Planets

2. http://www. businessinsider

3. Let’s take a second and appreciate our lives…
In order for life as we know it to form on Earth- we must fulfill some DIFFICULT requirements:
Liquid Iron Core
Liquid Water to be Present
Must be Tectonically Active
Must Possess Atmosphere
A large planet ‘buddy’ (to minimize asteroid impacts)
Billions of years of existence to evolve life

4. The earth fulfills ALL of these…
1. Liquid Iron Core
Creates a magnetic field called the magnetosphere
This help keeps us alive by deflecting the solar wind…

5. Liquid Iron Core (cont.)
The solar wind- High speed charged particles that the sun emits.
DANGEROUS TO US.
1. Can destroy atmosphere
2. Is harmful to humans
Without the magnetosphere to deflect these particles away, we would not be here.

6. A pretty cool thing about this…
This is the reason for the Aurora Borealis and the Aurora Australis
The Solar Wind (charged particles) react with a layer of the atmosphere to emit beautiful colors of light
Usually happens at the poles

7. Aurora Borealis

9. Doesn’t have to be night

10. 2. Liquid Water Must be Present
Habitable Zone- area in a star system in which liquid water is able to exist
Should be between K ( degrees Fahrenheit)
Different with every star
Higher mass stars = H.Z. further out
Lower mass stars = H.Z. closer in

11. Venus and Mars… Just a bit outside of the zone…
Venus to close to sun and Mars too far away

12. The Habitable Zone
Green area = the habitable zone

13. 3. Plate Tectonics
There must be a way to recycle nutrients such as Carbon, Oxygen, Hydrogen, etc.
Plate tectonics ensures Carbon is recycled in the atmosphere
No Carbon = No Carbon Dioxide = No Plants
Volcanic Activity = Helps create an atmosphere
(Let’s not get too crazy on this topic, this is for Ms. Zolynsky’s class!)

14. Just know… No plate tectonics = probably no atmosphere
Planet with most volcanoes ? Venus.
Planet with thickest atmosphere? Venus

15. Mars… Used to be tectonically active
Used to have an atmosphere of Carbon and Oxygen
Scientists think Mars looked like this back in the day

16. 4. Atmosphere Incredibly important for life Regulates heat
Blocks UV radiation (Harmful to humans)
Greenhouse Gas effect retains heat
Retains molecules essential for life

17. Greenhouse Gas Effect
Greenhouse Effect- when heat/energy is trapped by gases in our atmosphere
This is actually a good thing! Without this, we would die.

18. Without Greenhouse Effect…
Earth would be on average ZERO degrees Fahrenheit!
All water would freeze
Most life would die out

19. In all honesty…
Al Gore is probably right- humans are putting in an irregular amount of CO2 into our atmosphere- but that debate is not for this class…

20. 5. A Large Planet ‘Buddy’ Thanks Jupiter!
Actually… while Jupiter does absorb some asteroids... it also ‘flings’ some towards earth

21. 6. Billions of years for life to evolve
Remember, first hundreds of millions of years had a period of heavy bombardment
Planets still ‘accreting’
Very dynamic time
Lots of asteroids being flung around
Earth was being hit by a lot of these
Happens relatively early in formation

22. Evolution Life arose about 3.5 billion years ago
Remember: Earth is 4.5 billion years old
Many catastrophic events happened over this time
Asteroids/Comets
Massive volcanic activity
Ice Ages

23. Life as we know it (micro scale)…
1. Life as we know depends on a few other micro- level things 1. Carbon 2. Nitrogen 3. Oxygen 4. Hydrogen These create amino acids, DNA, and other essentials needed for life

24. Why these elements?
Hydrogen, Oxygen, Carbon, are very abundant in the universe
Odds are ‘they’ would use these elements before other ones
Carbon can form many bonds, meaning it can make many molecules to create life

25. NEEDS LIQUID LIQUID MEDIUM
2. Life requires molecules to ‘move around’ within cells
NEEDS LIQUID

26. Liquids NEEDS LIQUID OR GAS
Needs a way for molecules to be transported INTO and OUT of the organism
NEEDS LIQUID OR GAS

27. Which means this liquid should…
Dissolve some things (but not all)
Not react with certain compounds (to enable reactions)

28. So… life on other planets

29. Remember Life as we know it required all of the previous information
Other life may be a bit different, but we can assume it still needs much of the previous information, with perhaps some changes

30. Some examples… Photosynthesis: THE SOURCE OF ALL ENERGY ON OUR WORLD
We should all know this equation:
Photosynthesis: THE SOURCE OF ALL ENERGY ON OUR WORLD

31. Using Carbon Dioxide and Hydrogen sulfide to make a sugar (energy)
But somewhere else…
A different organism (on a different world) may make sugar (energy) differently:
Using Carbon Dioxide and Hydrogen sulfide to make a sugar (energy)

32.
This actually happens on earth, too…

33. Point being….
Organisms may adapt to drastically different ways to make energy
So organisms may use different methods to ‘live’ on other planets
Instead of oxygen, perhaps breath in hydrogen?
Instead of water, perhaps liquid methane?
Instead of carbon molecules, perhaps silicon molecules?

34. Other good molecules for life…
Instead of….. Perhaps ‘they’ use….
Oxygen to breathe Sulfur
Carbon for DNA and other life molecules Silicon
Nitrogen for life molecules (amino acids) Phosphorus

35. Some possible areas… Titan- as mentioned in The Cosmos
Atmosphere? Yes (Nitrogen)
Liquid? Yes (Methane)
Magnetosphere? Yes (Saturn’s)
Green House Yes (Methane)

36. Europa:
One of Jupiters Moons
One of Jupiter’s Moons

37. Europa
Jupiter’s Moon, believed to have a large subsurface liquid water ocean
Atmosphere? Small (Oxygen)
Plate tectonics? Maybe (some evidence)
Molecules? Yes (C, O, H, Si,)
Liquids? Yes (water)

38. Mars (Perhaps in the past)
Mars USED to… 1. Be tectonically active 2. Have an atmosphere 3. Have liquid water 4. (Probably) have a magnetosphere But that was all in the past (billions of years ago )

39. And now some cool Mars pics (and Patriotism)
(In reference to London 2012 Summer Olympics, The Mars Rover landed on Mars in Summer of 2012)

40. Mars Rover (Landed on Mars in Summer 2012)

41. Valleys thought to have been carved from water
Crazy pics of Mars…
Valleys thought to have been carved from water

42. A large lake? Perhaps a waterfall fell into a large river here?
Crazy Pics Cont.
A large lake? Perhaps a waterfall fell into a large river here?

43. More remnants from possible rivers
Cont.
More remnants from possible rivers

44. You can check out Mars on Google Earth if you have it downloaded!
Mars Ice Lake!
You can check out Mars on Google Earth if you have it downloaded!

45. Outside of the Solar System…
These are just some… They are finding more and more and more every day

46. One definition to know
Exoplanet - planet outside the solar system that revolves around a different star than our own

47. Gliese 581 A red dwarf star, much smaller than earth
22 light years from the sun (pretty close actually)
1/3 mass of sun

48. Some scale…

49. Habitable Zone of Sun and Gliese

50.
Some food for thought

51. Gliese 667 C c
This planet is part of Gliese 667, a trinary star system, thought to hold life. An artist’s impression

52. Kepler 452-b