by Koh Joo Beng
Overview•   The Sun•   History of Eclipses•   Geometry•   Observing•   Phases•   Oddities•   Videos/Slideshows•   Upcoming...
The SunVolume: 1,300,000 EarthsMass: 333,000 EarthsPower: 4 x 1026 W(50,000 billion reactors)0.0005 % reaches Earth
“Parts” of the Sun
CME!7 Jun 2011
Photon’s “walk”• Photon (initially gamma ray) is  created by thermonuclear  fusion• Reaches convective region  only after ...
Brief History of   Eclipses
Geometry of EclipsesNot to Scale!
Types of Solar                                    Eclipses                                             • Total or Annular?...
A Coincidence?• Sun is 400 times larger than the Moon• Sun is 400 times farther than the Moon• Both objects subtend angle ...
Why not 13 eclipses a              year?• On Youtube at http://youtu.be/E1B3RLf1A1s• Or search Youtube for “Solar Eclipse ...
Observing an Eclipse           Never look directly              at the Sun,   Except DURING            especially with a  ...
Observing phases  of an Eclipse Shade 14 Welder’s glass
Phases of a                Total Eclipse• 4 “Contacts” depending on which “limb” or  edge of Moon-Sun is in contact.      ...
Diamond Rings &           Bailey’s Beads• Possible to see only at 2nd and 3rd contact
Oddities
The Corona!  1/64 sec           2 sec      Composite
Videos/Slideshows
China              Total Eclipse 2008• On Youtube at http://youtu.be/Gm3EVERbx_c• Or search Youtube for “Joo Beng’s Total ...
Slideshows• Kenya 2010• South America 2010
Annular Eclipse   Kenya 2010
Easter Island             Total Eclipse 2010• On Youtube at http://youtu.be/OWgOmHm6JHs• Or search Youtube for “Easter Isl...
Coming Solar                 Eclipses• 2011  – 1 Jul : Partial Eclipse – Antarctica  – 25 Nov: Partial Eclipse – Antarctic...
Total Eclipse 13 Nov 2012
Eclipse Resources• MrEclipse.com : http://www.mreclipse.com/MrEclipse.html    – Ultimate resources for eclipses• NASA Ecli...
Questions?
Thank you!!    If you have any questions,        do send an email tojoobeng@astrobargains.com
The End
Backup material
Do you want to know more                                    about Astronomy?• Basics of Astronomy                         ...
To purchase your own telescopeor other astronomy-related equipment,visit www.astrobargains.com
Other useful links• Stellarium - Planetarium program www.stellarium.org• Celestia – Space Simulation www.shatters.net/cele...
Overview• Objective: Give audience an appreciation of the beauty of Sun, and share the                             • Phase...
Upcoming SlideShare
Loading in...5
×

Heavenly shadows

551

Published on

I created and shared this presentation about Solar Eclipses at the Annual IPS-NYP Astronomy Retreat at Nongsa Point on Batam in 2011.

Published in: Travel, Technology, Sports
0 Comments
0 Likes
Statistics
Notes
  • Be the first to comment

  • Be the first to like this

No Downloads
Views
Total Views
551
On Slideshare
0
From Embeds
0
Number of Embeds
0
Actions
Shares
0
Downloads
0
Comments
0
Likes
0
Embeds 0
No embeds

No notes for slide

Transcript of "Heavenly shadows"

  1. 1. by Koh Joo Beng
  2. 2. Overview• The Sun• History of Eclipses• Geometry• Observing• Phases• Oddities• Videos/Slideshows• Upcoming Eclipses• Resources
  3. 3. The SunVolume: 1,300,000 EarthsMass: 333,000 EarthsPower: 4 x 1026 W(50,000 billion reactors)0.0005 % reaches Earth
  4. 4. “Parts” of the Sun
  5. 5. CME!7 Jun 2011
  6. 6. Photon’s “walk”• Photon (initially gamma ray) is created by thermonuclear fusion• Reaches convective region only after 20,000~100,000 yrs!• Collides with others along the way and loses energy to become visible light photon• Radiates away at the surface of the Sun• Takes only 8 minutes to get to Earth
  7. 7. Brief History of Eclipses
  8. 8. Geometry of EclipsesNot to Scale!
  9. 9. Types of Solar Eclipses • Total or Annular? Is due to the elliptical orbit of the Moon (and also the Earth) – Moon at apogee = Annular Eclipse.Not to Scale! – At perigee = Total Eclipse • Total Eclipse over a particular city is once in 370 years! Total Annular Partial
  10. 10. A Coincidence?• Sun is 400 times larger than the Moon• Sun is 400 times farther than the Moon• Both objects subtend angle of 0.5 degrees!• Is physics involved? Or just pure luck?• Moon is receeding 4cm/yr.• 100 million years ago, no annular eclipses• 100 million years later, no more total eclipses!• Can’t see a total eclipse on any other planet.
  11. 11. Why not 13 eclipses a year?• On Youtube at http://youtu.be/E1B3RLf1A1s• Or search Youtube for “Solar Eclipse Educational Video”• Or click here.
  12. 12. Observing an Eclipse Never look directly at the Sun, Except DURING especially with a moment of telescope TOTAL ECLIPSE Instant and irreparable eye damage can occur.
  13. 13. Observing phases of an Eclipse Shade 14 Welder’s glass
  14. 14. Phases of a Total Eclipse• 4 “Contacts” depending on which “limb” or edge of Moon-Sun is in contact. 1st Contact 2nd Contact 3rd Contact 4th Contact
  15. 15. Diamond Rings & Bailey’s Beads• Possible to see only at 2nd and 3rd contact
  16. 16. Oddities
  17. 17. The Corona! 1/64 sec 2 sec Composite
  18. 18. Videos/Slideshows
  19. 19. China Total Eclipse 2008• On Youtube at http://youtu.be/Gm3EVERbx_c• Or search Youtube for “Joo Beng’s Total Solar Eclipse 2008”• Or click here.
  20. 20. Slideshows• Kenya 2010• South America 2010
  21. 21. Annular Eclipse Kenya 2010
  22. 22. Easter Island Total Eclipse 2010• On Youtube at http://youtu.be/OWgOmHm6JHs• Or search Youtube for “Easter Island Solar Eclipse 2010”• Or click here.
  23. 23. Coming Solar Eclipses• 2011 – 1 Jul : Partial Eclipse – Antarctica – 25 Nov: Partial Eclipse – Antarctica• 2012 – 20 May : Annular Eclipse – USA-Japan-Fuzhou – 13 Nov : Total Eclipse – Pacific-Australia (Cairns)• 2013 – 10 May : Annular Eclipse – Pacific-Australia – 3 Nov : Hybrid Eclipse – Africa
  24. 24. Total Eclipse 13 Nov 2012
  25. 25. Eclipse Resources• MrEclipse.com : http://www.mreclipse.com/MrEclipse.html – Ultimate resources for eclipses• NASA Eclipse website : http://eclipse.gsfc.nasa.gov/eclipse.html – For lots of Technical Data• Java Solar Eclipse Explorer : http://eclipse.gsfc.nasa.gov/JSEX/JSEX-AU.html – Calculator to determine eclipses viewable from Singapore (or any other city) – Previous Total Eclipse on 4 Mar 1821! – Next Annular Eclipse on 26 Dec 2019! – Next Total Eclipse on 5 Jul 2168!• Eclipse in a Different Light : http://sunearthday.nasa.gov/2006/multimedia/storyteller.php – Eclipse stories, folklore
  26. 26. Questions?
  27. 27. Thank you!! If you have any questions, do send an email tojoobeng@astrobargains.com
  28. 28. The End
  29. 29. Backup material
  30. 30. Do you want to know more about Astronomy?• Basics of Astronomy • Astronomy Equipment – Astronomical vocabulary, distance units, parsec, – Refractors, Reflectors, Cassegrains and other light year telescope designs – The motion of the planets, elliptical orbits, – Telescope mounting systems, Alt-Az vs Keppler’s laws. Equatorial. – Seasons, and why they occur, Earth’s tilt. – Astrophotography, Polar alignment, Focusing in – The Lunar Cycle the dark, CCD, Image processing – Eclipses, how they occur, differences between – Telescopes in Space, Hubble, Chandra. Lunar and Solar eclipses – Large telescopes of the World, Keck, VLSI, VLT, – Local coordinates, Celestial coordinates, Galactic ELT, coordinates, • Solar system overview and Birth Theory. – Newton ’s Laws – Earth – Nature of light – The Moon• History of Astronomy – The Sun as a star. – The Scientific Method – Mercury, Venus, Mars – Ancient astronomers, Galileo, Copernicus, Tycho – Jupiter, Saturn, Uranus, Neptune Brahe – Pluto, discussion of Pluto being a minor planet. – Archaeastronomy – Comets and asteroids, Meteorites.• Intermediate Astronomy • Cosmology – Colour of Stars, Relationship of Colour to – The Big Bang, Big Crunch temperature – Einstein’s Theory of Relativity, Special, General – Spectral lines and chemical composition – Relativistic Doppler Shift – The Inverse square law of brightness, H-R – Cosmological Constant Diagram – The Doppler effect – Hubble’s Law – Multi-wavelength astronomy, Radio, X-ray, – Expansion of the Universe Infrared, Gamma-ray. – Cosmic Microwave Background – Black Holes, Quasars and Active Galaxies, – COBE, WMAP Neutron stars, Pulsars, White Dwarfs • And much much more.... – Galaxies, The Milky Way
  31. 31. To purchase your own telescopeor other astronomy-related equipment,visit www.astrobargains.com
  32. 32. Other useful links• Stellarium - Planetarium program www.stellarium.org• Celestia – Space Simulation www.shatters.net/celestia• Singastro – Singapore’s astronomy forum www.singastro.org• Singastro Wiki - Wiki for Astronomy Beginners in Singapore www.singastro.org/web/mediawiki• Astronomy.sg – Singapore astronomy portal www.astronomy.sg• Printable Sky Charts – Cartes du Ciel www.stargazing.net/astropc• Interactive Sky Charts – From Sky & Telescope : http://www.skyandtelescope.com/observing/skychart/ – Astronomy Magazine : http://www.astronomy.com/asy/stardome
  33. 33. Overview• Objective: Give audience an appreciation of the beauty of Sun, and share the • Phases of the eclipse thrill of a total solar eclipse • 1st to 4th contacts• Format : Slides, videos, with narration. Use Starry Night to show. Minimal • Diamond ring, Bailey’s Beads interaction. • Corona • Oddities of eclipses• Overview of Sun – parts of the Sun • Shadow bands – light through fluid. • Photosphere, Chromosphere, Corona – thin hot atmosphere of Sun. Shaped by • Solar crescents magnetic field. • Shadow racing from West to East • Prominences – plumes of gas, Sunspots, Filaments, • Twilight effect – setting sun colours. • How long it takes photon to emerge – solar walk • Videos of eclipses• Stories of eclipses • Mongolia • Dragon eating Sun • Easter Island • Sun-Moon lovers fighting • Kenya • Sun-Moon Lovers hiding in darkness • Coming eclipses • Sun angry, hiding for a while • Annular eclipse – May 2012, USA • 585BC – Central Turkey Meades and Linions, battle of 5 yrs, was predicted by • Total eclipse – Nov 2012, Fiji astronomers, but soldiers didn’t know. Eclipse was sign that they should not fight. Cemented bond with double marriage. • Solar eclipse resources • 1919 Evidence for General Theory of Relativity – Arthur Eddington, • Mr Eclipse – Fred Espenak• Geometry of eclipses • Eclipse path maps • Sized by chance? Moon receeding…4cm/yr. 100m yrs no more eclipses. 100m yrs • Total and annular path forecasts ago, no annulars. Can’t even see corona, so not as fun. No other planet can ever see a total eclipse (e.g. Mars moons too small, Jupiters too big) • Omitted: • New Moon. • Planning the eclipse • Partial, Annular vs Eclipse, Hybrid • Prioritize one feature to look at. • Orbit is elliptical – variation of Moon at Apogee (smaller) and Perigee (larger) • Earth’s orbit also elliptical • Don’t photograph • Hybrid eclipse – Annular-Total-Annular • Enjoy • Video – why eclipses don’t occur 13 times a year • Timing, practice practice practice. • Timing of eclipses – few seconds – max 7.5 min. Mostly 2min. • Solar photography/videography • 1 in 360 yrs eclipse is over a city. So have to travel to see it. • Built-up corona – insufficient dynamic range in cameras• Observing eclipses • Eclipse sequencing - photoshop • Warning - Power of the Sun. Do not look at the Sun without protection. Melted • Equipment eyepiece cap? • Zoom • Filters, not during totality • Camera • Always before the objective, never at the eyepiece. • Exposure settings • When telescopes pointed at Sun, must be attended. • Focus • Solar glasses • Creative eclipse photos • Shade 14 Welder’s glass • Name eclipse – Singapore? • Telescope projection - refractors • Pin-hole projection • • Sunspotter • Bucket of water?

×