Transcript PH1600: Introductory Astronomy

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PH1600: Lecture 1
A Grand Tour of the Universe
PH1600: Introductory Astronomy
Lecture 1: A Grand Tour of the Heavens
School: Michigan Technological University
Professor: Robert Nemiroff
TAs: Ashley Ames & Martin Boluyt
Term: Fall Semester 2008
No formal book: Only lectures, Wikipedia pages, & APOD pages
Good background reading book:
The Cosmos by Pasachoff & Filippenko
Online Course WebCT pages: courses.mtu.edu
Physical Class Time: Monday & Wed 10:05 – 10:55 am
Physical Class Location: Rekhi G005 (Basement)
This class can be taken online ONLY, class attendance is not
required!
Goal:
A Beautiful & Free Astronomy Course
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Beautiful space pictures are used to
liberally illustrate space themes
All course material is freely
available over the Internet
Still, this course is rigorous, collegelevel, accurate and up-to-date
Beautiful Space Pictures
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Usually chosen from the daily
updated Astronomy Picture of the
Day (APOD: apod.nasa.gov)
Includes the most recent astronomy
images, not yet available in printed
text books
Includes the most beautiful
astronomy images, which help
define our time
Free Astronomy Course
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Text taken from freely available
wikipedia.org
In astronomy, wikipedia is often
more up-to-date than textbooks
Information is free, but diplomas
cost money
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to receive college credit, you need to
register at a university and pay money!
You are responsible for…
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Lecture material
Wikipedia pages (cited in lectures)
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APODs posted during the semester
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Anything on those pages can appear on
quizzes or tests, even if I never mention them
during my lecture(s)
Use only wikipedia.org pages as they appeared
on September 1, 2008
September 1 – December 15 inclusive
APOD review every week during lecture
Completing the Quizzes
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Chapter 1 quiz now online
Wikipedia entries of today
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Universe
Electromagnetic Spectrum
Light Year
Cosmic Questions
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What does “universe” mean?
How big is the universe?
What is the largest thing in the universe?
What is the smallest thing in the
universe?
How old is the universe?
These will all be addressed during this
course! Here, though, are some quick
answers:
Cosmic Answers:
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There are many definitions to “universe”
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Earth, visible universe, causally connected brane,
etc.
Wikipedia entry: Universe
http://en.wikipedia.org/w/index.php?title=Universe
&oldid=235892226
Size of visible universe: 13.7 billion light years in
radius
Largest thing: Superclusters (100 million light
years across
Smallest thing: electron, photon, neutrino, other
fundamental particles
Universe Age: 13.7 Billion light years
Light Year:
Slow Light is a Time Machine
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“Light year” is a unit of distance
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An object one light year away is seen as it
was one year ago. Etc!
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The distance light travels in one year
You can only see the past
We can almost see back to the beginning of
the universe
Light could circle the Earth about 7.5
times in one second
Wikipedia entry: light year
Speed of light: example calculation
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c = speed of light = 3 x 108 meters/sec
Q: The sun is (about) 8 light minutes
away – how far is that in meters?
A: distance = velocity x time
d=ct
= (3 x 108 m/sec)x(8 min)x(60 sec/min)
= 1.44 x 1011 meters
Light is more colorful than we can see.
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Visible light: red to blue
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Almost visible light: infrared to ultraviolet
Entire Electromagnetic Spectrum:
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ROY G BIV
Radio waves, microwaves, infrared, visible
(red, blue), ultraviolet, X-rays, gamma-rays
Different animals perceive light differently
The Sun is green
Wikipedia entry: Electromagnetic
Spectrum
Array of Radio Telescopes
ley, AUI, NRAO, NSF
y 14
Jets from Radio Galaxy 3C296
Credit & Copyright: AUI, NRAO
APOD: 2002 February 26
A Year of Resolving Cosmology
Credit: WMAP Science Team, NASA
APOD: 2003 December 31
The Galactic Center in Infrared
Credit: 2MASS Project, UMass, IPAC/Caltech, NSF, NASA
APOD: 2006 July 16
The Coma Cluster of Galaxies
Credit & Copyright: Jim Misti (Misti Mountain Observatory)
APOD: 2006 March 21
Dark Sun Sizzling
Credit: TRACE Project, Stanford-Lockheed Inst., NASA
APOD: 2006 July 12
SN 1006: Supernova Remnant in X-Rays
Credit: J. Hughes (Rutgers) et al., CXC, NASA
APOD: 2005 December 26
Fermi's First Light
Credit: NASA, DOE, International LAT Team
APOD: 2008 August 28
The Sky at Night
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All stars seen are in our Milky Way
Galaxy, most are near our Sun
Stars
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Constellations
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Big Dipper, Little Dipper, etc.
Planets
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Orion, Ursa Major (Big Bear), etc.
Asterisms
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Sirius, Polaris, etc.
Venus, Jupiter, etc.
Central Plane of our Galaxy
Sirius: The Brightest Star in the Night
Credit & Copyright: Juan Carlos Casado
APOD: 2000 June 11
Ceci n'est pas un Meteore
Credit & Copyright: Laurent Laveder (PhotoAstronomique.net)
APOD: 2006 August 19
Dusk of the Planets
Credit & Copyright:
Jerry Lodriguss
APOD: 2002 April 29
Raining Perseids
Credit & Copyright: Fred Bruenjes
APOD: 2007 August 12
Astronomy Pictures of the Day
(APODs) from the past week…
APODs reviewed today:
Monday, 2008 September 1 through
Wednesday, 2008 September 3
Web site: apod.nasa.gov