Download Purpose of Astro 102/104 Perfect timing

Astronomy 102/104: Our Solar System
Lecture #1: Introduction & Outline
Prof. Jean-Luc Margot & Prof. Steve Squyres
• Course Goals--why take Astro 102/104?
• Our philosophy, and a promise.
• Rules of the Road:
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Logistics
Expectations
Responsibilities
Communication
• Detailed Syllabus.
Astro 102/104
Purpose of Astro 102/104
Perfect timing
• To learn about our origins and our connection to
the universe. To develop an appreciation for Earth
as a fragile planetary body in a vast cosmos.
• To understand key principles and processes that
govern the natural world. What is the solar system
like today? Why? How did it get that way?
• To become familiar with the scientific process.
To acquire tools for further inquiry and learning.
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• This is a "Golden Age" of exploration!
• Spacecraft are exploring the planets now!
– MESSENGER (’04-now): Mercury.
– Magellan (’90-’94): Venus.
– Mars Pathfinder ((’97)
97), MGS (’97
( 97-’06)
06), Mars Odyssey
(’02-now), MER (’04-now), MRO (’06-now): Mars.
– NEAR (’97-’01), Hayabusa (‘05): asteroids.
– Deep Impact (’05), Stardust (’04-’06): comets.
– Galileo (’95-’03): Jupiter, satellites.
– Cassini/Huygens (’04-now): Saturn, satellites.
– Voyager (’80s): Jupiter, Saturn, Uranus, Neptune.
– AND MORE PAST, PRESENT, AND FUTURE!
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First flyby of Mercury in 30+ years
reveals astonishing landforms!
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Lakes and rivers of methane on Titan!
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Astonishing worlds: Iapetus & Hyperion
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New Discoveries Being Made!
• Observations of asteroids:
– Many are highly porous. WHY?
– Some have satellites! HOW?
• Satellites of Jupiter
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and Saturn:
– Europa may have an ocean!
– Titan has hydrocarbon rain and rivers!
• Many objects discovered beyond Neptune.
– Hundreds of trans-Neptunian objects.
– Pluto demoted! Can they do that?
• Many Sun-like stars have planets!
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Methods
Will there be math?
• Discover and Explain important patterns and
trends in the data.
• GOAL is to UNDERSTAND these patterns, NOT
memorization of facts or numbers.
numbers
• At a lower level than
what’s in the get rich book.
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• Will concentrate on patterns and processes, but
some knowledge of facts will be needed.
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some geometry
some algebra
smidgen of trigonometry
no calculus
no logarithms
no differential equations
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Some Obvious Patterns
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Some Striking Differences
• Example: Our Moon vs. Jupiter’s moon Io.
– Rocky worlds, about the same size.
Inner Planets
• Io:
– Volcanic.
V l i
– Covered with orange sulfur.
differ from
• Moon:
– Geologically dead.
– Covered with gray rock.
Outer Planets.
• WHY?
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• WHY?
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Many Obvious Questions
Timescales
• Why do outer planets have rings?
• How and when did the solar system form?
– (Answer: ~4,600,000,000 years ago!)
• What are rings, anyway?
• How do we know that??
• Are they permanent or temporary?
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Why Understand the Past?
How Has the Solar System Evolved?
• Extrapolation in time
predictions about the future.
– How will Earth's atmosphere change?
– How will our climate change?
– Will objects strike the Earth? When?
• Extrapolation in space
inferences about other places.
– Many other stars have planets.
– Could some of them be Earthlike?
– Could there be life??
• Everything changes (Why? How? How Fast?)
• Examples:
– 4 billion years ago the Earth's atmosphere was
very different than it is today (little or no oxygen)
oxygen).
– 4 billion years ago there may have been rivers or
lakes on Mars (today it is a cold, bone dry desert).
– Mars has 2 moons today, but in 1 billion years it
will have only 1 moon.
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Major Course Topics
Some Philosophy
• Our goal is to help you learn how to distinguish
solid science from nonsense.
• For example:
(1) General Solar System Concepts.
(2) The Inner Solar System.
(3) Small Bodies and the Outer Solar System.
(4) Origins.
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Planets around other stars.
Repeated massive mass extinctions due to impacts.
Evidence of ancient life on Mars.
Ice at the poles of the Moon and Mercury.
• Which of these are TRUE, POSSIBLY TRUE,
EXAGGERATIONS, OR EVEN NONSENSE?
• Use Carl Sagan’s baloney detection kit.
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A Promise from us...
And from you...
• We will work hard to help you learn.
• Our Responsibilities:
– Clearly present the information.
– Provide opportunities for questions, discussion.
– Be prepared for lectures, sections, labs.
– Provide fair and consistent grading.
– Make astronomy matter!
• But you must work hard too!
– Come to Lecture:
• Be here on time: prompt 11:15 start.
• Class will end at 12:05 (not 12:00…)
– Go to Section.
– Do the reading.
– Turn in assignments on time.
– Ask Questions!
• Absolute academic integrity expected at all times.
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Lecture Style
Handouts:
Syllabus
and
Ground Rules
• Follows the textbook, but not verbatim.
• More information provided only in lecture.
• Other lecture features:
– "The
" h Main
i Point"
i " hi
highlighted
hli h d for
f eachh class.
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– Active learning.
– Group activities.
– Demonstrations.
– Discussions: Astronomy in the News, etc.
– Mars rover mission updates.
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Astro 102/104
Your Weekly Section Meeting
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Lab: Astro 104
Your chance for more personal contact.
Weekly quizzes or problem sets assigned.
Detailed discussion of reading, lectures.
Detailed discussion of homework.
Critical preparation for prelims & final.
You will get a better grade if you attend lectures
and sections.
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• Astro 104 has an additional lab component.
• Four classroom lab activities (in Clark 132):
– Radioactive Dating.
– Planetary Orbits.
– Impact Cratering.
– Rotation of Saturn and its Rings.
• One on-campus observatory activity (at Fuertes
Observatory, weather permitting).
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Observing the Sky
Additional Resources
• On clear Friday evenings, the Cornell
Astronomical Society holds open-house observing
at Fuertes Observatory on north campus, from
8:00 pm to midnight.
midnight
– Check http://astro.cornell.edu/facilities/fuertes
• You are strongly encouraged to go out and see the
planets with your own eyes! Dress warmly.
• Planetarium program (SkyGazer) comes with your
textbook.
• Course website:
http://www.astro.cornell.edu/courses/a102
– Lecture notes, homeworks, links, etc.
• Textbook publisher website:
http://www.masteringastronomy.com
– Animated figures, tutorials, quizzes, etc.
• Numerous planetary data archives:
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– Header graphic based on images from
http://www.solarviews.com © Calvin J. Hamilton
For Additional Help
Next Lecture...
• Office Hours:
– Prof. Margot: MF 3:00-4:30 (but call ahead).
– Prof. Squyres by appointment only (due to
continuing
i i Mars rover operations).
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• Each TA has his/her own office hours:
– Consult the handout or web site for details.
• Any of us are available at other times by
appointment, with advance notice.
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• The Sky.
• Historical Overview of Planetary Science.
• Reading this week:
– Preface and Chapter 1.
– Chapter 2.1, 2.4.
– Chapters 3, 4.
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