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Extraterrestrial Life. Antígona Segura Peralta. Penn State University, College of Earth and Mineral Sciences Penn State Astrobiology Research Center. They do exist!. Astrobiology. Astrobiology is the science that studies the origin, evolution and distribution of life in the Universe.
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Extraterrestrial Life Antígona Segura Peralta Penn State University, College of Earth and Mineral Sciences Penn State Astrobiology Research Center
Astrobiology Astrobiology is the science that studies the origin, evolution and distribution of life in the Universe
The origin of life on Earth 4 billion years ago
What does life need? • Raw materials: hydrogen, carbon, oxygen, nitrogen and minerals like iron and sulfur. • Energy: Sun, volcanoes • A liquid: Water
Planets, the perfect place • They contain raw materials • Energy sources • They can have liquid water
Our Solar System Uranus Pluto Saturn Jupiter Neptune Venus Mercury Earth Mars
The terrestrial planets Very hot because its atmosphere Mercury Mars Very near the Sun Venus No atmosphere, cold but…
Mars, an interesting past Ancient volcanoes Ancient rivers?
The giant planets Jupiter Saturn Neptune Uranus
Milky Way 100 billion of stars!
Where the stars are born Molecular cloud
Formation of stars and planets Beta Pictoris, a newborn star
Formation of stars and planets Beta Pictoris disk (artist conception)
The life of the stars Red Giant Panetary nebula and white dwarf Yellow dwarf 10 billion years
The life of the stars Blue giants 100 million years Supernova remmanent and neutron star Supernova
A habitable world Characteristics: • Distance from its star, not too far, not too close • Size, not too big, not too small • Atmosphere to keep the planet warm and water liquid • Water
Biomarkers Those features whose presence or abundance can be attributed to life
Small things can make big changes Cyanobacteria
How to find a planet? Problem: The stars emit light (a lot!) and planets doesn’t, they just reflect the light from their parent star. • How to solve it? • Cover the star!!!! • Measure the effects of the planets on the stars: • Stars wobble because of the planets • Stars dim when a planet crosses in fron of them
Looking for habitable worlds Kepler: • Look for terrestrial planets around 100,000 stars. • Launch on 2006.
Looking for habitable worlds Terrestrial Planet Finder (TPF): • Look for terrestrial planets around 100 nearby stars. • Analyze the planets to detect those that may be habitable • Launching on 2012-2015
Looking for habitable worlds • Eddington: • Looking for planets bigger than Mars around 500,000 stars. • Launching on 2008.
Looking for habitable worlds • Darwin: • Look for terrestrial planets around 1,000. • Launching after 2014.
Globular Cluster M13 Intelligent life? Arecibo Antenna, Puerto Rico
SETI: Search for extraterrestrial life Allen array Project Phoenix