extraterrestrial life antígona segura peralta penn state university, college of earth and mineral...
TRANSCRIPT
Extraterrestrial
Life
Antígona Segura Peralta
Penn State University, College of Earth and Mineral SciencesPenn State Astrobiology Research Center
They do exist!
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
Mercury Venus Earth Mars
Jupiter SaturnUranus
Neptune
Pluto
The terrestrial planets
Very near the Sun
Very hot because its atmosphere
No atmosphere, cold but…
Mercury
Venus
Mars
Mars today
Mars, an interesting past
Ancient volcanoes
Ancient rivers?
Mars might be like this
Little martian?
The giant planets
JupiterSaturn
UranusNeptune
Europa, Jupiter’s moon
Europa
Europa
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)
Extrasolar planets
The life of the stars
Yellow dwarf10 billion years
Red Giant
Panetary nebula and white dwarf
The life of the starsBlue giants
Supernova
Supernova remmanent and neutron star
100 million years
A habitable world
Characteristics:
Distance from its star, not too far, not too close
Size, not too big, not too smallAtmosphere to keep the planet warm
and water liquidWater
BiomarkersThose features whose presence or
abundance can be attributed to life
Signatures of 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 worldsKepler:
Look for terrestrial planets around 100,000 stars.
Launch on 2006.
Looking for habitable worldsTerrestrial 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 worldsEddington:
Looking for planets bigger than Mars around 500,000 stars.
Launching on 2008.
Darwin:
Look for terrestrial planets around 1,000.
Launching after 2014.
Looking for habitable worlds
Intelligent life?
Arecibo Antenna, Puerto Rico
Globular Cluster M13
The Pioneer mesage
Voyager
SETI: Search for extraterrestrial life
Allen array
Project Phoenix
A habitable world