Lecture 4: The Sun

Further reading

There is a truly enormous number of excellent web sites about the Sun. I can't possibly list them all here, but here are a few to get you started:

• Check out Galileo's drawings of sunspots at "The Galileo Project", http://galileo.rice.edu/index.html; look in Science > Sunspots > Galileo's Sunspot Drawings
• NASA's Heliophysics page: http://science.nasa.gov/heliophysics/
• The Stanford Solar Center, http://solar-center.stanford.edu, has lots of useful stuff, including current solar images
• The Solar Dynamics Observatory is at http://sdo.gsfc.nasa.gov/
• The SOHO web site is at http://sohowww.nascom.nasa.gov/, where you can find all SOHO's amazing images
• The STEREO web site is at http://stereo.gsfc.nasa.gov/
• There's a good introduction to the Sun at http://www.solarviews.com/eng/sun.htm
• You can hear the Sun singing (actually, solar oscillation data converted to sound and scaled up to human hearing range) at http://soi.stanford.edu/results/sounds.html
• A NASA article about the Quebec blackout: http://www.nasa.gov/topics/earth/features/sun_darkness.html
• You can find current solar images from a huge number of sources and wavelengths at 
http://umbra.nascom.nasa.gov/images/latest.html
• There's a marvelous series of images of the Sun published in the Boston Globe http://www.boston.com/bigpicture/2008/10/the_sun.html
• The World data center for the Sunspot Index is at the Royal Observatory of Belgium http://sidc.oma.be/index.php

Sources for images used:

• Solar Dynamics Observatory image of the Sun: from http://sdo.gsfc.nasa.gov/gallery/main/item/151
• Solar interior: from "The solar interior", http://solarscience.msfc.nasa.gov/interior.shtml
• Photon transport: from http://solarcellcentral.com/sun_page.html
• Solar granulation movie: from Peter Brandt, http://www.kis.uni-freiburg.de/~pnb/granmovtext1.html (broken link)
• Helioseismology: from Stanford's Helioseismic and Magnetic Imager (HMI) page http://hmi.stanford.edu/Description/hmi-overview/hmi-overview.html
• Refraction of waves: after Fig. 5.3 from "Journey from the Center of the Sun" by Jack Zirker
• Travelling waves in the Sun: from Helio- and Asteroseismology, http://solar-center.stanford.edu/helio-ed-mirror/english/engrays.html
• 1D vibrations: from PIRA Physics Test/Lecture Drawings, http://www.wfu.edu/physics/pira/PhysicsDrawings.htm#waves
• 2D vibrations: from Chladni Plate Mathematics by Paul Bourke, http://astronomy.swin.edu.au/~pbourke/modelling/chladni/. Used with permission.
• 3D vibrations: from Graphical representations of surface harmonics, http://gong.nso.edu/images/harmonics.shtml
• Vibrating Sun: from The Singing Sun, http://solar-center.stanford.edu/singing/singing.html
• Doppler imager and velocity fields: from Helio- and Asteroseismology, http://solar-center.stanford.edu/helio-ed-mirror/english/engdop-obs.html
• GONG sites: from http://gong.nso.edu/sites/
• SOHO orbit: from http://www.esa.int/esapub/bulletin/bullet86/huber86.htm and http://spaceguard.rm.iasf.cnr.it/NScience/neo/neo-what/ast-trojans.htm
• MDI/SOHO power spectrum: from http://solar-center.stanford.edu/art/lnu.html
• Resuts from MDI/SOHO: from Helioseismology, http://soi.stanford.edu/results/heliowhat.html
• Sunspot: from Some images of a medium size sunspot by Peter Brandt, http://www.kis.uni-freiburg.de/~pnb/spottext1.html
• Sunspot group AR 2192, from APOD 2014 October 24, http://apod.nasa.gov/apod/ap141024.html
• Galileo's sunspot drawings: from http://galileo.rice.edu/sci/observations/sunspot_drawings.html
• Sunspot numbers: from http://www.sciencedirect.com/science/article/pii/S1364682612000648
• SOHO continuum and magnetogram images: from SOHO Latest Images, http://sohowww.nascom.nasa.gov/data/latestimages.html
• Structure of a sunspot: from D. A. Gough, "Vainu Bappu Memorial Lecture: What is a sunspot?", Fig, 9, http://arxiv.org/abs/0909.5338
• Polarity of sunspots: from Nature of the Universe, Chapter 11: The Sun, http://www.physics.hku.hk/~nature/notes/lectures/chap11.html; magnet picture from http://www.windows2universe.org/sun/atmosphere/sunspot_magnetism.html
• Cycle 24 sunspot numbers: from "Solar Cycle #24: On Track to be the Weakest in 100 Years" http://www.universetoday.com/103803/solar-cycle-24-on-track-to-be-the-weakest-in-100-years/
• Solar cycle observed by SOHO: from APOD 2007 December 3 http://apod.nasa.gov/apod/ap071203.html
• Solar magnetic fields: from 15-Phys-121: Astronomy and the Nature of the Universe by M. Hanson, http://www.physics.uc.edu/~hanson/ASTRO/LECTURENOTES/W03/Lec4/Page8.html
• Solar spectrum: by Nigel Sharp (NSF,NOAO), from APOD 2006 April 23 http://apod.nasa.gov/apod/ap060423.html
• Chromosphere: from Astr 1010: Survey of Astronomy, http://www.physics.utoledo.edu/~lsa/_a1010/mod25.htm
• Chromosphere features: from Evans Solar Facility Images, http://nsosp.nso.edu/esf/pics.html
• Solar spicules: from APOD 2008 November 2 http://apod.nasa.gov/apod/ap081102.html
• Earth compared to prominence: from SDAC, http://umbra.nascom.nasa.gov/sdac.html. Prominence: SOHO EIT image from 2005 July 29 at 18:24 UT, same site.
• Corona during an eclipse: from Astr 1010: Survey of Astronomy, http://www.physics.utoledo.edu/~lsa/_a1010/mod25.htm
• TRACE movie of coronal loops: from Solar Physics: Coronal features, http://science.nasa.gov/ssl/PAD/SOLAR/feature3.htm
• Solar flare: from Solar Physics: Solar flares, http://science.nasa.gov/ssl/PAD/SOLAR/flares.htm
• Flare from AR2192, from APOD 2014 Nov 22 http://apod.nasa.gov/apod/ap141122.html
• Animation of solar flare: from Best of SOHO Movies, http://sohowww.nascom.nasa.gov/
• LASCO movie of coronal mass ejection event: from Best of SOHO Movies, http://sohowww.nascom.nasa.gov/
• Magnetic loop and Yohkoh image: from Yohkoh Public Outreach Project: The Magnetic Sun, http://solar.physics.montana.edu/YPOP/Spotlight/Magnetic/loops.html
• Sequence of CME images from 5 Nov 1998: from Best of SOHO images Part 1, http://sohowww.nascom.nasa.gov/
• Animation of a CME impacting the Earth: from Best of SOHO Movies, http://sohowww.nascom.nasa.gov/
• Aurora over Alaska, image by Jan Curtis, from Astronomy Picture of the Day 2000 May 19, http://apod.nasa.gov/apod/ap000519.html
• Aurora over volcano: photo by Lucas Jackson http://blogs.reuters.com/photo/2010/04/26/luck-is-a-funny-thing/
• Richard Kerr: "Space Weather Forecasting: Are We Ready for the Next Solar Maximum? No Way, Say Scientists", Science 324 1640
• STEREO concept and orbit: from http://stereo.jhuapl.edu/gallery/images/artConcepts.php
• STEREO current location: from http://stereo-ssc.nascom.nasa.gov/where.shtml
• All STEREO movies from the STEREO Gallery http://stereo.gsfc.nasa.gov/gallery/stereoimages.shtml
• SDO movie: from SDO First Light Movies http://sdo.gsfc.nasa.gov/gallery/firstlight/
• The heliosphere: from The Galactic Environment of the Sun by Priscilla Frisch, American Scientist Jan-Feb 2000, http://www.americanscientist.org/template/AssetDetail/assetid/21173
• Voyagers entering the solar heliopause: from " Voyager Enters Solar System's Final Frontier", http://www.nasa.gov/vision/universe/solarsystem/voyager_agu.html

Last updated 7 December 2016