prof. d. l. depoy fall 2013fall 2013people.physics.tamu.edu/depoy/astr111tr/notes/lecture1a.pdf ·...
TRANSCRIPT
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Astronomy 111:Astronomy 111: Overview of Modern Astronomy
Prof. D. L. DePoyFall 2013Fall 2013
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Course DescriptionCourse Description
• This course will cover the roots of modern astronomy, the scientific method, fundamental physical laws, the nature and formation of p ys ca a s, t e atu e a d o at o oplanets, stars, and galaxies, and an introduction to cosmology. The course includes an integrated laboratory that reinforcesan integrated laboratory that reinforces concepts learned in lecture and includes supplemental information related to the lecture topics, including hands-on experience withtopics, including hands on experience with telescopes and digital imaging of celestial objects. This course is not open to students who have taken ASTR101 or ASTR314.
ASTR111 Lecture 1
who have taken ASTR101 or ASTR314.
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Course ObjectivesCourse Objectives
• Explain the scientific process and how scientific theories are developed and tested.
• Recall basic physical concepts such as gravitational and ti l d h li ht d tt i t tconservation laws, and how light and matter interact.
• Describe the general characteristics of our solar system and the universe.
• Apply scientific thinking to the natural world to understand• Apply scientific thinking to the natural world to understand, e.g. what powers the sun, why galaxies differ, and how the universe began.
• Formulate a scientific hypothesis, identify a testableFormulate a scientific hypothesis, identify a testable prediction, verify by carrying out an experiment, and assess the results.
• Work effectively in a laboratory group.
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Class websiteClass website
• Class Website:– http://faculty.physics.tamu.edu/depoy/astr111.html/
Contents• All course handoutsAll course handouts• Online lecture notes
Links for further exploration• Links for further exploration
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Online lecture notesOnline lecture notes
• Outlines of the electronic overheads shown in class
• Posted to the website each week in advanceadvance
• Includes lecture graphics & computer animationsanimations
• They’re free...
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TextbooksTextbooks
• Textbooks: – “The Essential Cosmic Perspective” byThe Essential Cosmic Perspective by
Bennett et al– “Astronomy 111 Handbook” (available at y (
Notes & Quotes)
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TextbookTextbook
Suggested readings will be from Essential Cosmic Perspective• Will be skipping some extraneous or overly
detailed sections.• Readings are assigned by topic rather than
by lecture• Lecture sequence may not follow book
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Office hoursOffice hours
• On demand:On demand: – Please email me to request an appointment at any
time.– I have two offices
• Munnerlyn 204y– Building is locked and generally inaccessible
• Mitchell Institute 240I ill b th TTh i d ft– I will be there TTh mornings and afternoons
– Email is by far the best way to contact me!
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TAsTAs
• Brett Salmon and others• Office hoursOffice hours
– ???• Email to arrange meetings• Email to arrange meetings
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Lab CoordinatorLab Coordinator
• Dr. J. Marshall• Email to arrange meetingsEmail to arrange meetings
– Only if necessary
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GradingGrading
• On-line Pre-lectures and In-Class Exercises (10%)
• Three Mid-term Exams (45%): multiple choice• Three Mid-term Exams (45%): multiple choice • Final Exam (20%): multiple choice • Laboratory (25%): 10 labs completed over the
course of the semester
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GradingGrading
• Approximate Grading Scale:A (>90%) B (80–89%) C (70–79%) DA (>90%), B (80 89%), C (70 79%), D (60–69%), F (<60%)
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Pre-lecturesPre-lectures
• Weekly videos to watch and answer questions aboutq
• Exercises in class about material• Starts next week• Starts next week• All will be available on eCampus
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Mid-term examsMid-term exams
• Three mid-term exams• Multiple choice questionsMultiple choice questions• Worth 45% of final course grade
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Final ExamFinal Exam
• Comprehensive & cumulative• Multiple choicep• Worth 20% of final course grade
N M k Fi lNo Makeup Finals
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LabLab
• 10 labs completed over the course of the semester.
• Lab sections meet the first week of class in MPHYS 331
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LabLab
• Bring lab handbook (from Notes & Quotes), a sturdy lab notebook, and a ), y ,writing implement with you to each lab
• Lab will be graded on attendanceLab will be graded on attendance, completion of labs in your lab notebook, and short weekly quizzesand short weekly quizzes
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ASTR111 Lecture 1
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In class assessmentIn class assessment
• Astronomy Concept Inventory• Will not be gradedWill not be graded• For my benefit to determine what you
already knowalready know• Helps to decide if class has been
ff tieffective
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ASTR111 Lecture 1
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What is Astronomy?What is Astronomy?
“astron” = starastron = star“nomos” = law
Astronomy is the science of stars andAstronomy is the science of stars and clusters of stars, galaxies and clusters of galaxies, planets, “dwarf planets” and g , p , ptheir satellites, asteroids and comets, interstellar gas and dust, and everything else in the Universeelse in the Universe
A lot to cover in one semester…
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“The most incomprehensible thing about the Universe is that it is comprehensible ”it is comprehensible.
Albert Einstein
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Three Questions:Three Questions:
1) What is it?– Describe it: how bright, far, energetic, etc.Describe it: how bright, far, energetic, etc.
2) How does it work?)– Underlying Physics (testable theories)
3) How does it evolve?– How does it form, develop & end its
ASTR111 Lecture 1
o does o , de e op & e d sexistence?
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ASTR111 Lecture 1
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Main Topics:
• The Night SkyHistory of Astronomy & Science• History of Astronomy & Science
• Light and Matter• The Solar System• Structure and Evolution of Stars• Structure and Evolution of Galaxies• Structure and Evolution of the Universe• Frontiers of Modern Astronomy
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The Night Sky
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The Night SkyThe Night Sky
• Observed motions of the sky• Definitions of day year etcDefinitions of day, year, etc.• Seasons
N i ti• Navigation• Long term changes
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The History of AstronomyThe History of Astronomy
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The History of AstronomyThe History of Astronomy
• Ancient Observatories and Measurements• Tycho, Kepler, Copernicusy p p• Galileo• Newton• Development of the Scientific Method
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Light and MatterLight and Matter
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Light & MatterLight & Matter
• Light– PhotonsPhotons– Wavelengths and energies
• Matter• Matter– Fundamental particles
F• Forces– Four fundamental forces
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The Solar SystemThe Solar System
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The Solar SystemThe Solar System
• Terrestrial planets• Jovian planetsJovian planets• Other stuff
A t id– Asteroids– Comets
D f l t– Dwarf planets• Formation of the Solar System
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The Structure and
Evolution of
Stars
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The Structure & Evolution of Starsof Stars
• Observed properties of stars– distances, motions, brightness, temperature, etc.g p
• Physics of stars– internal structure– sources of energy
• Stellar EvolutionStellar Evolution– formation, development, and final states
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The Structure and Evolution of
Galaxies
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The Structure & Evolution of GalaxiesEvolution of Galaxies
• Observed properties of Galaxies– distances, sizes, shapes– constituents (stars, gas, and dark matter)
• Physics of Galaxiesy– structure and dynamics
• Evolution of GalaxiesEvolution of Galaxies– star formation histories– interactions with other galaxies
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The Structure and Evolution of
the Universe
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The Structure & Evolution of the UniverseUniverse
• Observed Characteristics– size, age, constituentssize, age, constituents
• Physics of the Universespace time and gravitation– space, time, and gravitation
• Evolution of the Universeorigin of the Universe– origin of the Universe
– development (Big Bang theory)– fate of the Universe
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fate of the Universe
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Frontiers of ModernFrontiers of Modern Astronomyy
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Frontiers of Modern AstronomyAstronomy
• What is Dark Matter and Dark Energy?
• Are there other planets in the Galaxy?
• Are there giant Black Holes in galactic
nuclei?nuclei?
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The Challenges of AstronomyThe Challenges of Astronomy
• We can’t “touch”, we can only observe.• Vast, unbridgeable distancesg
– hard to measure distances accurately– sometimes hard to measure distances at
all!all!• Long times (millions & billions of years)
properties of “populations” of objects– properties of “populations” of objects– cosmic “lookback”: distance=time
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Planet: The EarthPlanet: The Earth
13 000 kil t
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13,000 kilometers across
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Satellite: The MoonSatellite: The Moon
380,000 kilometers away
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3,500 kilometers across
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Star: The SunStar: The Sun
150 million kilometers away
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1.4 million kilometers across
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Cluster of Stars: The PleiadesCluster of Stars: The Pleiades
430 light-years away
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430 light years away15 light-years across
1 light year = 9.4605284 × 1012 kilometers
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Gas & Dust: The Lagoon NebulaLagoon Nebula
5000 light-years away0 li h
ASTR111 Lecture 1
50 light-years across
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Galaxy: The Andromeda GalaxyGalaxy: The Andromeda Galaxy
2,200,200 light-years away80 000 li ht
ASTR111 Lecture 1
80,000 light-years across
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Cluster of Galaxies: ComaCluster of Galaxies: Coma
320 million light-years away10 illi li h
ASTR111 Lecture 1
10 million light-years across
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ASTR111 Lecture 1