Astronomy 1010Fall_2015Day-11

Planetary Astronomy

Course Announcements• SW chapter -2 due: Mon. 9/21; 2pm• How is the lunar observing going?• 1st Quarter night – Mon. 9/21 -7:30pm – on campus• Exam 1: Mon. Sept. 21• This Week: APSU-OUR: Research & Creative Activity

Week. Events in the library 2:30-3:30 every day.

Lecture – TutorialPredicting Moon Phases: pg 85

Work with a partner!Read the instructions and questions carefully.Discuss the concepts and your answers with

one another.Come to a consensus answer you both agree on.If you get stuck or are not sure of your answer,

ask another group.If you get really stuck or don’t understand what

the Lecture Tutorial is asking, ask one of us for help.

i_Clicker QuestionClassAction: Questions: Lunar Cycles: Identify Lunar Position from Phase

i_Clicker QuestionClassAction: Questions: Lunar Cycles: Phases Visible; option 1

Stuff in Chapter 2• Coordinates• Position• Daily Motion (spin of Earth on its

axis)• Visibility of the sky• Year Motion (Earth orbits the Sun)• Seasons (tilt of the Earth’s axis)• Precession of the equinoxes• Motion and phases of the Moon• Eclipses

Three types of solar eclipses:• Total: The Moon

completely blocks the Sun’s light.

• Partial: Only part is blocked.

• Annular: The Sun appears as a bright ring surrounding the Moon.

Solar Eclipses

Solar eclipses happen at new Moon. Moon passes between Earth and the Sun. Only a small portion of Earth can witness

each one.

The part of the Moon’s shadow you are in determines which type of solar eclipse you see.

Umbra: Total or annular. Penumbra: Partial.

Lunar eclipses happen at full Moon. Earth is between the Sun and the

Moon. Visible over a wider area of Earth. Last a lot longer than solar eclipses.

Eclipses do not occur every month because the Moon’s orbit is tilted 5.2° with respect to Earth’s orbit around the Sun.

Intersection: line of nodes.

Next one is April 15, 2014 for

North America

i_Clicker QuestionClassAction: Questions: Phase2, Eclipse2, Tides; option 1

The Saros Cycle…18 years 11.3 days

What Would You See on Mars?

Projected Eclipse Times Eclipse Path Point of Greatest Eclipse

Lat.: 36.9664° NLong.: 87.6639° W Total Solar Eclipse Duration of Totality: 2m40.1s

APSU Observatory Lat.: 36.5631° N

Long.: 87.3433° W Total Solar EclipseDuration of Totality: 2m23.4s

Projected Eclipse Times APSU Observatory

Lat.: 36.5631° NLong.: 87.3433° W Total Solar EclipseDuration of Totality: 2m23.4sMagnitude: 1.008

Event Date Time (UT) Alt Azi (C1) : 2017/08/21 16:56:59.80 62.3° 149.7° (C2) : 2017/08/21 18:25:28.70 64.2° 198.9°

Max : 2017/08/21 18:26:40.50 64.1° 199.5° (C3) : 2017/08/21 18:27:52.10 64° 200.2° (C4) : 2017/08/21 19:52:25.50 53.4° 235.2°

Projected Eclipse Weather

Clarksville, TN

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