lecture 27, december 9, 2010 astr 101, section 3 instructor, jack brandt [email protected] 1astr...
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LECTURE 27, DECEMBER 9, 2010
ASTR 101, SECTION 3INSTRUCTOR, JACK BRANDT
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a) planets in the Milky Way Galaxy.b) planets with life in the universe.c) stars with planets like Earth.d) civilizations in our Galaxy.e) terrestrial planets with water.
Question 1
The Drake equation attempts to define the number of
a) planets in the Milky Way Galaxy.b) planets with life in the universe.c) stars with planets like Earth.d) civilizations in our Galaxy.e) terrestrial planets with water.
Question 1
The Drake equation attempts to define the number of
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a) temperatures on a planet are reasonable.b) terrestrial planets can form around a star.c) terrestrial planets could have liquid water on their
surfaces.d) liquid water can condense into rain in the
atmosphere.e) Sun-like stars can exist in the Milky Way Galaxy.
Question 4
The habitable zone is the area where
a) temperatures on a planet are reasonable.b) terrestrial planets can form around a star.c) terrestrial planets could have liquid water on their
surfaces.d) liquid water can condense into rain in the
atmosphere.e) Sun-like stars can exist in the Milky Way Galaxy.
Question 4
The habitable zone is the area where
Stellar habitable zones
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a) in radio light where natural emissions from our Galaxy are minimal.
b) on Mars where liquid water has been proven to exist in the past.
c) on the Moon where water is believed to exist under ice in a deep crater.
d) in the Oort cloud where comets rich in water are formed.
Question 6
The “water hole” is a region
a) in radio light where natural emissions from our Galaxy are minimal.
b) on Mars where liquid water has been proven to exist in the past.
c) on the Moon where water is believed to exist under ice in a deep crater.
d) in the Oort cloud where comets rich in water are formed.
Question 6
The “water hole” is a region
The “water hole” may be the best part of the
electromagnetic spectrum for intelligent civilizations to
communicate across the vast reaches of space.
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TEST NO. 4
• TIME: Tuesday, December 14, 2010, 12:30 PM
• PLACE: Regener 103
• MATERIAL: Topics covered since Test No. 3
• NO. 2 PENCIL: Bring one!
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REVIEW, CHAPTER 14THE MILKY WAY GALAXY
• Milky Way Galaxy-Basic structure (disk, halo, bulge), type, motions, Sun’s location, formation
• Important variable stars-RR Lyrae stars, Cepheids
• Spiral arms-Winding problem, density wave theory, 21-cm line
• Rotation curve and dark matter• Central region-Sgr A*, star orbits, black hole
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REVIEW, CHAPTER 15NORMAL AND ACTIVE GALAXIES
• Types of galaxies(spirals, barred spirals, ellipticals), Hubble’s classification
• Irregular galaxies, Magellanic Clouds• Distance ladder, Standard Candles (Tully-Fisher
relation, Type I supernovae)• Clusters of galaxies• Hubble’s Law, Hubble’s constant, red shifts• Active galaxies, time variations, colliding galaxies• Quasars-distances, central engines, and massive
black holes
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REVIEW, CHAPTER 16GALAXIES AND DARK MATTER
• Dark matter clues– rotation curves, clusters of galaxies, Head-Tail galaxies, gravitational lensing, Bullet Cluster
• Look-back time• Galaxy formation and evolution, starburst
galaxies, central black holes• Galaxy surveys, large-scale structure of the
universe• Matter in the universe is mostly dark
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REVIEW, CHAPTER 17-1COSMOLOGY
• Cosmological principle, Olbers’ paradox• Big Bang, expansion of the universe, Hubble
time, fate of the universe• Curvature of space• Cosmic acceleration, dark energy, mass-
energy composition of the universe
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REVIEW, CHAPTER 17-2COSMOLOGY
• Cosmic Microwave Background (CMB), origin, Penzias and Wilson
• Element formation in the Big Bang• Inflation, horizon problem, flatness problem• Large-scale structure formation
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REVIEW, CHAPTER 18LIFE IN THE UNIVERSE
• Necessary chemical compounds are wide-spread in the cosmos
• Miller-Urey experiment, amino acids• Drake equation, habitable zones, estimated
number of advanced civilizations in our Galaxy• Extra-terrestrial communication, “Water-Hole”