Transcript PH1600: Introductory Astronomy

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PH1600: Introductory Astronomy
Lecture 14: Stars: Single and Binary
PH1600: Introductory Astronomy
Lecture 14: Star: Single and Binary
Study: Chapter 11 in The Cosmos book
Next Lecture: Star Clusters
School: Michigan Technological University
Professor: Robert Nemiroff
Book: The Cosmos by Pasachoff & Filippenko
Online Course WebCT pages:
http://courses.mtu.edu/
This class can be taken online ONLY, class
attendance is not required!
You are responsible for…
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Reading the book
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APODs posted during the semester
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One chapter per “quiz period”
Anything from that chapter can appear on
quizzes or tests, even if I never mention them
during my lecture(s)
This quiz period covers Chapter 11
APOD review every week during lecture
Completing the Quizzes
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Chapter 1, 2, 4, 6, 7, 8, &10 quizzes already
due
Chapter 11 quiz due next
See WebCT at http://courses.mtu.edu/ for
details
Henrietta Leavitt Calibrates the Stars
Credit: AAVSO
APOD: 2000 September 3
Stars: Distant Suns
Stellar Spectral Types: OBAFGKM
Credit & Copyright: KPNO 0.9-m Telescope, AURA, NOAO, NSF
APOD: 2004 April 18
http://upload.wikimedia.org/wikipedia/en/4/44/HRDiagram.gif
http://abyss.uoregon.edu/~js/ast122/lectures/lec11.html
http://abyss.uoregon.edu/~js/ast122/lectures/lec11.html
http://abyss.uoregon.edu/~js/ast122/lectures/lec11.html
Orion Star Colors
Credit and Copyright: David Malin
APOD: 1998 August 29
Famous Stars
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Sun
Polaris
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North star
Sirius
Betelgeuse
Alpha Centauri
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Proxima Centauri
Polaris: The North Star
Credit & Copyright: Wally Pacholka
APOD: 1999 October 6
Sirius: The Brightest Star in the Night
Credit & Copyright: Juan Carlos Casado
APOD: 2000 June 11
X-Rays From Sirius B
Credit: NASA/ CXC/ SAO
APOD: 2000 October 6
Resolving Mira
Credit: M. Karovska (Harvard-Smithsonian CfA) et al., FOC, ESA, NASA
APOD: 2001 January 21
A Giant Starspot on HD 12545
Credit & Copyright: K. Strassmeier (U. Wien),
Coude Feed Telescope, AURA, NOAO, NSF
APOD: 2003 November 2
Betelgeuse, Betelgeuse, Betelgeuse
Credit: A. Dupree (CfA), R. Gilliland (STScI), NASA
APOD: 1999 June 5
Simulated Supergiant Star
Credit: B. Freytag, (U. Uppsala)
APOD: 2000 December 22
Why Stars Twinkle
Credit: Applied Optics Group (Imperial College), Herschel 4.2-m Telescope
APOD: 2000 July 25
Inverse Square Law of Brightness
http://en.wikipedia.org/wiki/Image:InverseSquareLaw.png
Example
Stars A and B are identical. Star B
is at twice the distance of star A.
How much brighter does star A
appear than star B?
 Use inverse square law: lA =k/rA2
Also, lB=k/rB2. Therefore lA/lB=(rB/rA)2
= 22 = 4.
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Proxima Centauri: The Closest Star
Credit & Copyright: David Malin, UK Schmidt Telescope, DSS, AAO
APOD: 2002 July 15
Alpha Centauri: The Closest Star System
Credit: 1-Meter Schmidt Telescope, ESO
APOD: 2003 March 23
Binary Stars
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Visual Binaries
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Spectroscopic binaries
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Doppler color changes
Eclipsing Binaries
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Can see two or more
Dark times
Astrometric Binaries
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Wobble
Albireo: A Bright and Beautiful Double
Credit & Copyright: Richard Yandrick (Cosmicimage.com)
APOD: 2005 August 30
http://en.wikipedia.org/wiki/Image:Orbit5.gif
The Big Dipper Cluster
Credit & Copyright: Noel Carboni
APOD: 2006 March 17
Mizar Binary Star
Credit: J. Benson et al., NPOI Group, USNO, NRL
APOD: 1997 February 19
http://csep10.phys.utk.edu/astr162/lect/binaries/spectroscopic.html
http://en.wikipedia.org/wiki/Eclipsing_binary
Mira: The Wonderful Star
Illustration Credit: M.Weiss(CXC)
APOD: 2005 May 5
NGC 3132: The Eight Burst Nebula
Credit: Hubble Heritage Team (AURA/STScI /NASA)
APOD: 2003 September 13
An Intermediate Polar Binary System
Illustration Credit & Copyright: Mark Garlick (Space-art)
APOD: 2003 November 10