Download - Exoplanets and Extraterrestrial Life
EXOPLANETSAND E.T. LIFE
OUTLINE•Introduction: The Solar System•Exoplanets•Exoplanet Detection•Planetary Habitability•A Glimpse on the Drake Equation
Intro: The Solar System•the Sun•Planets•Dwarf Planets•Asteroids•Meteoroids
•Comets•Dust•Gas
Intro: The Solar System
Exoplanets•from Ancient Greek exo—”outer, external” + planet•planets outside the solar system that orbit around a star•a.k.a. extrasolar/exosolar planets
Exoplanets •Mercurian•Subterran•Terran•Superterran•Neptunian•Jovian
Exoplanets•51 Pegasi b is the first planet found orbiting around another Sun-like star. (1995)• There are 1894 confirmed exoplanets as of March 2015.
Exoplanets: Detection•Ground-based telescopes
Hobby-Eberly Telescope
Exoplanets: Detection• Space telescopes
Hubble Space TelescopeKepler Space Telescope
Exoplanets: Detection•Method 1: Transit Method
--detecting a drop in a star’s brightness as a planet transitsacross its disk.
Exoplanets: Detection•Method 2: Wobble Method
--detecting a slight change in a star’sposition while a planet orbits around it.
Exoplanets: Detection•Method 3: Direct Imaging
--taking a direct picture of an exoplanet.
Can life existon exoplanets?
Criteria for life: a ChecklistAdequate Star Size
Criteria for life: a ChecklistAdequate Star Size
• the Life Zone
Criteria for life: a ChecklistRight planetary characteristics
• Terrestrial type
• Massive
Criteria for life: a ChecklistPresence of essential elements• SPONCH CaFe S- Sulfur
P- PhosphorusO- OxygenN- NitrogenC- CarbonH- Hydrogen
Ca- CalciumFe- Iron
Criteria for life: a ChecklistPresence of water
Potentially Habitable Exoplanets
•The current number of confirmed potentially habitable exoplanets as of Mar. 2, 2015 is 29. (Planetary Habitability Laboratory)
• 10 are Earth-sized and 19 are Super-Earths.
Potentially Habitable Exoplanets
Potentially Habitable Exoplanets
Kepler-22 b
Potentially Habitable Exoplanets
Kapteyn b
Potentially Habitable Exoplanets
tau Ceti e
Is there intelligent life elsewhere in our Universe?
The Drake equation• The Drake equation was
made by Dr. Frank Drake of the Search for Extraterrestrial Intelligence (SETI) Institute.• it estimates the number of
probable intelligent and active civilizations throughout our home galaxy
The Drake equation
The Drake equationPessimist
R* 5 per yearfp 0.05fl 0.5ne 1fi 0.01fc 0.01L 1,000 years
OptimistR* 10 per yearfp 0.2fl 1ne 2fi 0.1fc 0.1L 10,000 years
N = 0.0125 N = 400
Final thoughts“ Our Sun is one of 100 billion stars in our galaxy. Our galaxy is one of billions of galaxies populating the universe. It would be the height of presumption to think that we are the only living things in that enormous immensity.”
--Wehner von Braun
Final thoughts“Really, it’s okay to reserve judgment until the evidence is in.”
--Carl Sagan
Thank you, Earthlings!