Other Planetary Systems

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Other Planetary Systems
Over 130 extrasolar planets have been discovered
since 1995 The Extrasolar Planet Encyclopedia
Stars are too far away from the Sun, and direct
imaging cannot detect planets near them Current
strategy involves watching for the small
gravitational tag the planet exerts on its
star The tag can be detected using the Doppler
effect
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Planet Transits
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The Nature of Extrasolar Planets
The discovery of extrasolar planets gives us an
opportunity to test the solar system formation
theory
Most of the discovered planets are different from
those of our system They are mostly Jupiter-size
and located closer to their stars But possible
planet migration discovered planets are
exceptions
The Kepler Project will look for terrestrial
planets around other stars
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Life outside the Solar System
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NASC 1100

• Our Physical World
• The Course Overview

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Course structure

• Methodology of Science (lecture 1)
• Overview of our place in the Universe (lecture 2)
• Physics (August 27 ? October 1)
• Chemistry (October 4 ? October 22)
• Earth Science (October 27 ? November 12)
• Astronomy (November 15 ? December 8)
• The Course Summary (December 10)
• Final Exam (December 16)

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The Scientific Method
The Scientific Method is a general scheme for
looking at the Universe
The 4 major steps of the scientific method

• Formulating a problem
• Observation and Experiment
• Interpreting the Data
• Testing the Interpretation by further Observation
  and Experiment

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Main Laws of Physics
Newtons Laws Keplers Laws Conservation of
Energy Conservation of Momentum (angular
momentum) Coulombs Law Ohms Law Laws of Ideal
Gas The Doppler Effect (types of
waves) Electromagnetic Waves (spectral
regions) Energy is directly proportional to
frequency
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Atomic Physics
Models of Atom (Rutherford, Bohr) Chemical
Elements (isotopes) Concept of Binding
Energy Fusion and Fission Elementary
Particles The Periodic Law
10
Inorganic Chemistry
Elements, Mixtures, and Compounds Chemical Bonds
(covalent, polar covalent, ionic) Electronic
Shells (open and closed) States of Matter (solid,
liquid, gas, plasma) Crystalline and Amorphous
substances Electron gas in metals Van der Waals
forces Solutions (saturated and
unsaturated) Liquids (polar and
nonpolar) Dissociation (acids, bases, salts, pH
scale) Chemical Energy (electron potential energy)
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Organic Chemistry
Carbon bonds Alkanes (organic compounds
containing C and H) Petroleum Structural Formulas
(H ? C ? C ? H) Saturated and Unsaturated
hydrocarbons Functional Groups (hydroxyl,
carbonyl, carboxyl) Monomers and
Polymers Carbohydrates, Lipids, Amino Acids
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Earth Sciences
Atmosphere and Hydrosphere Atmospheric
composition (N, O, CO2, noble gases) Clouds
(saturated and unsaturated air) Winds (Coriolis
Force) Weather Systems (cyclones and
anticyclones) Climate Ocean Currents Rocks
(igneous, sedimentary, metamorphic) Rock Cycle,
Minerals Earths structure
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Astronomy
Solar System Stars Galaxies The Universe
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The Solar System
Creation from one molecular cloud Central star
(the Sun) Two families of planets (terrestrial
and Jovian) Small objects - asteroids (rocky
leftovers) and comets (icy leftovers)
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Stars
Objects that emit radiation in whose interiors at
some point fusion reactions H -gt He takes place
. Masses 0.08 - 100 Msun. Lifetimes few
million - few billion years Low-mass,
intermediate-mass, and high-mass stars. The
Hertzsprung - Russell diagram.
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Galaxies and Universe
Huge stellar systems (up to 1 trillion
stars) Spiral, elliptical, and irregular
galaxies Hubbles Law - universal
expansion Quasars - early galaxies with
extremely luminous nuclei (perhaps, due to
supermassive black holes) Dark matter ?
invisible mass that explains galactic rotation
laws and formation of galaxies
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The Universe
The Big Bang theory ? the theory of the
universes earliest moments. It predicted the
cosmic microwave background (radiation from the
moment when the Universe became transparent for
photons, T 2.7 K) and the proportion of the
primordial He to H (1/3). Age of the Universe
is approximately the inverse Hubble constant (14
billion years)
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Sample Questions for the Final Exam
Definition questions
What is a scientific theory? Types of mechanical
waves How does the force of gravity depends on
the distance between the objects? What is
chemical energy? What are igneous rocks? What is
weight?
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What Happens to Saturated Air if
it cools?
Saturated air cannot take more moisture. At
higher temperatures air can get more
moisture. Thus, if saturated air cools, water
has to condense out.
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Stellar Luminosity
Luminosity is the total amount of power the star
radiates into space. It is measured in power
units (Watts).
Brightness of a star in the sky depends on the
distance towards a star and its luminosity.
The apparent brightness is the amount of light
reaching us per unit area.
Apparent brightness obeys an inverse square law
with distance.