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
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
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
Our Physical World
The Course Overview
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)Course structure
The Scientific Method is a general scheme for looking at the Universe
The 4 major steps of the scientific method
Conservation of Energy
Conservation of Momentum (+angular momentum)
Laws of Ideal Gas
The Doppler Effect (types of waves)
Electromagnetic Waves (spectral regions)
Energy is directly proportional to frequency
Models of Atom (Rutherford, Bohr)
Chemical Elements (isotopes)
Concept of Binding Energy
Fusion and Fission
The Periodic Law
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)
Alkanes (organic compounds containing C and H)
Structural Formulas (H C C H)
Saturated and Unsaturated hydrocarbons
Functional Groups (hydroxyl, carbonyl, carboxyl)
Monomers and Polymers
Carbohydrates, Lipids, Amino Acids
Atmosphere and Hydrosphere
Atmospheric composition (N, O, CO2, noble gases)
Clouds (saturated and unsaturated air)
Winds (Coriolis Force)
Weather Systems (cyclones and anticyclones)
Rocks (igneous, sedimentary, metamorphic)
Rock Cycle, Minerals
Creation from one molecular cloud
Central star (the Sun)
Two families of planets (terrestrial and Jovian)
Small objects -asteroids (rocky leftovers) andcomets (icy leftovers)
Objects that emit radiation in whose interiors at some point fusion reactions H -> 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.
Huge stellar systems (up to 1 trillion stars)
Spiral, elliptical, and irregular galaxies
Hubble’s 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
The Big Bang theory the theory of the universe’s 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)
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?
… 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.
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.