Astrobiology: an Introduction

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Astrobiologyan Introduction

• Georgia Tech Astronomy Club
• October 23, 2006

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Talk Objectives

• Introduction to Astrobiology
• Brief History
• Current Projects and Missions
• The Future of the Field

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What is astrobiology?
Introduction

• Astrobiology is the study of life in the
  universe. It investigates the origin, evolution,
  distribution, and future of life on Earth, and
  the search for Life Beyond Earth.
• -NASA astrobiology headquarters

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What is astrobiology?
Introduction

• Astrobiology is an interdisciplinary field
• Microbiology
• Astronomy
• Climate and Earth Science
• Evolution

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When did astrobiology begin?
History

• Questions about life beyond our planet have been
  around for a while in science and pop-culture.
• The term astrobiology first surfaced around
  1960 in scientific literature mostly speculation
  until the 1990s.

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The start of quantitative research
History

• In 1992, NASA funds the Exobiology Branch of the
  Space Science Division.
• Program expanded in 1996 to the Astrobiology
  program, which remains today.

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Microbiology of Extremophiles
Current Research

• The study of extreme organisms on
• earth can lead to a
  better
• understanding of
  how
• life may
  survive in
• other
  environments.

Thermophiles are heat-loving organisms that can
be found at temperatures as high as 177C (338F)!
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Microbiology of Extremophiles
Current Research

• Types of Extremophiles
• Ice lovers
• Thermophiles (land and ocean)
• Rock dwellers
• Acidophiles
• Alkaliphiles
• Halophiles
• Time travelers

Bacillus subtilis survived 6 years in a vacuum
similar to space.
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The role of Astronomy in Astrobiology
Current Research
Search for extrasolar planets Learning more
about possible life- accommodating
places in our solar system (Europa, Titan,
Mars?) Defining and discovering potential
habitable planets

• Dark Globule in IC 1396 (Spitzer Space Telescope)

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The role of Astronomy in Astrobiology
Current Research

• Current Research
• The possibility of life in the oceans below
  Europas thick ice crust
• Past/present life on Mars?
• Titans organic gases and continent could
  harbor life

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Climate and Earth Sciences
Current Research

• Gives an idea
• of how organisms
• are capable of altering the climate.
• Understanding Earths climate helps identify
  potential habitable planets and moons.
• From everything weve seen, Earth is a unique,
  very special case!

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Climate and Earth Sciences
Current Research

• Climate studies can also help with
• Self-sustaining systems for extended space travel
• The futuristic (and somewhat taboo) idea of
  terraforming

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Evolution and the Origin of Life
Current Research

• An important part of finding life elsewhere in
  the solar system is having an idea of how life
  forms.
• What is involved and necessary in the creation of
  life?
• How did life on earth form and evolve?

Stromatolites- algae fossils from 3.5bya
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Evolution and the Origin of Life
Current Research

• Panspermia or exogenesis- the idea that life came
  to earth from somewhere else in the universe
• RNA World theory- RNA able to store genetic
  information and self-replicate

Millers classic experimental setup.
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Evolution and the Origin of Life
Current Research
Would life evolve similarly on different planets
or moons? What selection pressures would be most
important? How does the common ancestor
influence the most highly evolved organisms?
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The Future of Astrobiology
Increasing funding cuts at NASA continue to make
headway difficult Many unanswered questions
Climate change and destruction,
overpopulation, or national conflicts may drive
humans to space exploration the last
resort Astrobiology is important for both
fundamental academic understanding of our origins
and our future and for practical reasons of space
exploration and resource management
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• And now a message from the President of the
  United States, George W. Bush...