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The Great Tennessee Eclipse 2017

MTSU Department of Physics & Astronomy

www.mtsu.edu/eclipse

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Goals for today

1) We convey our excitement for the eclipse2) You learn a little about how eclipses occur, and achieve a level of confidence for discussing eclipses with your students

Before August, we will supply you with curriculum to use in the classroom.

•How many have witnessed a total lunar eclipse?

•How many have witnessed a total solar eclipse? 

Why do we care so much?

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Lunar Phases

Lunar Eclipse Geometry

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Solar Eclipse Geometry

Galileo spacecraft, 1992

The last Middle TN total solar eclipse?

65 million years ago

20,000 years ago500 years ago

65 years ago

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Last occurrence: 1478 

• In 15 years Columbus will land in the Caribbean

• In 25 years  Leonardo will paint Mona Lisa• In 120 years Shakespeare will write “Romeo and Juliet”

Next opportunity: 2566

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WHY is it so rare?

•Compare relative sizes of  the Sun, Earth, and the Moon.

•Put them at the proper distance for our scale.

Geometry

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The Moon’s orbit is tilted

Sun

EarthMoon

Syzygy – a 3-Body AlignmentUnique geometryLunar orbit - orbit plane- orbit shape- lunar phase

Earth- rotation- spin-axis variations- orbit shape

Shadows- shape- size- duration

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Eclipse CyclesSolar Eclipses 1996-2020

Saros Cycle 18.03 years

Eclipse Path

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Eclipse Path90 min of totality across the US

shadow moves at average speed near 1500 mph

(Mach 2)

Eclipse Path

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Maps Where will you be on August 21 at 1:28 pm?

Maps Where will you be on August 21 at 1:28 pm?

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A Once-in-a-Lifetime DayAugust 21, 2017 Schedule at MTSU:

11:00 am: Campus festivities begin11:59 am: First contact! The moon begins to

pass in front of the sun.

1:29:08 pm- Totality!1:30:17 pm: Darkness falls across campus

2:55 pm: Last contact3:00 pm: Campus festivities end

We will have solar glasses …

astronomers …telescopes …

What’s it like?

Credit: Rick Fienberg

August 21, 2017

Changing daylightTwilight at 90% eclipseDiamond rings and beads Awesome Darkness!

… and celestial crownsTemperature feel differentChanges in nature

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You Might See …

How many stars and planets will you see?

Mercury

Sun

Arcturus

Jupiter

MarsVenus

Procyon

Sirius

Regulus

Ecliptic Plane

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Solar Eclipse Images

Pictures

http://www.zam.fme.vutbr.cz/~druck/Eclipse/Ecl2008m/Tse2008_200_mo1/0‐info.htm

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Videos

Credit Ken Offit, Rice UniversityDiamondRingfirst2012_KOffit_Rice_Univ

Other Videos

Australia, 2012 (3:39)https://www.youtube.com/watch?v=KZ2npH7zZ4A

2017 Simulation from Hopkinsville, KY (1:31)https://www.youtube.com/watch?v=vzJqeyxye_E

2016 Solar Eclipse (3:42)http://space.rice.edu/eclipse/solar_eclipse_2016/reiff_video/totality_253_Masked.mp4

2012 Solar Eclipse (0:31)http://space.rice.edu/eclipse/solar_eclipse_2012/Ken_Offit/

11 July 2010 Solar Eclipse (10:12, best part is 3:00 – 4:00)http://space.rice.edu/eclipse/solar_eclipse_2010/videos/

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ScienceSolar CoronaLunar Orbit correctionsGeneral RelativityTesting new instruments

A solar eclipse taken in Svalbard on March 20, 2015. Credit: Miloslav Druckmuller, Peter Aniol and Shadia Habbal

Safety1. Solar Eclipse Glasses2. Telescope with solar filter3. Pinhole projection4. Welders’ goggles (#14 or darker)5. Stand under a tree

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More Informationwww.mtsu.edu/eclipsehttp://www.visitmusiccity.com/eclipsehttps://eclipse2017.nasa.gov/

www.mtsu.edu/eclipse

Let’s go outside and SAFELY look at the sun!

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Basketball =  9.55” diameter (Earth)Baseball =  moonBasketball court = Sun

Lunar distance = 24 ftSolar distance = 1.8 miles

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Closing ThoughtWhy is the guy standing the closest to the empty beer bottles looking the wrong way?