1. Class 10:
Water/Life on
Other Planets

2. Astrobiology

3. Life’s Sequence on Earth
3.75
Billion
years ago
1.7
Billion
years ago
4.5
Billion
years ago
600
Million
years ago
500
Million
years ago
225
Million
years ago

4. Life As We Know It

5. Conditions for Life (I)
Liquid water

6. Conditions for Life (II)
Carbon

7. Conditions for Life (III)
Energy

8. Conditions for Life (IV)
Stable Environment

9. Life on Mercury? Moon?

10. Life on Venus? Earth? Mars?

11. Life on the Gas Giants?

12. Life on Europa?

13. Life on Titan?

14. Life on Mars?

15. The Habitable Zone

16. Searching for Life: Biomarkers

17. The Drake Equation Nc = N* x fp x nLZ x fL x fI x Fs
= # of communicative civilization in galaxy
Pessimistic
Estimate
Optimistic
Estimate
N*= # stars in galaxy x x1011
fp = fraction of stars w/planets
nLZ = number of planets in habitable zone
fL = fraction of planets where life could begin
fI = fraction of life forms that evolve to intelligence
Fs = fraction of star’s life where life communicates
Nc = 2x x106
• Pessimist: we are alone
• Optimist: many civilizations

18. Search for Extraterrestrial Intelligence
(SETI)
Search for Extraterrestrial
Intelligence
SETI Institute
Aricebo

19. SETI Projects nonprofit, $20M astronomy data - 2.3 million users,
• Project Phoenix: primary search,
nonprofit, $20M
SETI Projects
• SERENDIP: piggyback search of ordinary
astronomy data
Jill Tarter •
- 2.3 million users,
yrs computer
time each day

20. SETI Telescopes Effelsberg Big Ear Haystack Square Kilometer Array
Arecibo
Square Kilometer Array

21. The hmmmm….. Factor