Astronomy 1010-H
Planetary Astronomy
Fall_2015
Day-8
Course Announcements
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Read Chapter 2
How is the lunar observing going?
How is the sunset/sunrise observing going?
1st Quarter night – Mon. 9/21 -7:30pm – on campus
Exam 1: Fri. Sept. 18 or Mon. Sept. 21
This weekend: Thurs. - Sat. – Riverfest
This week: National Adopt a pet week
Next Week: APSU-OUR: Research & Creative Activity
Week. Events in the library 2:30-3:30 every day.
Astro-group meeting today 2:30pm, E109
Spacecraft Reports
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Chantal H. – New Horizons
Ashley G. – Dawn
Mahalia S. – NuStar
Tristan C. – Mangalyaan
Spencer B. – Voyager
Arielle P. – Curiosity Rover
Lars A. – Cassini
Sarah E. – Mars Odyssey
John M. – Mars Phoenix
Jordan T. – Galileo
Rashun B. – Apollo Missions
Definitions & Terms -1
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Season: A time of year characterized by a general weather
pattern (meteorological) or a location of the Earth in its orbit
around the Sun (astronomical).
Solar Day: 24 hours. The average time between successive
meridinal transits of the Sun.
Sidereal Day: 23h 56m. The time between successive
meridinal transits of a star.
Stuff in Chapter 2
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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
So, the Earth moves in two
ways that affect what we see
Orbital motion around the sun
causes seasonal changes in the
constellations
Rotational motion around the polar
axis causes changes over the course
of the night
Lecture – Tutorial
Solar vs Sidereal Day: pg 11
 Work with a partner!
 Read the instructions and questions carefully.
 Discuss the concepts and your answers with each
other.
 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.
Why does the sky change
during the course of a night?
The Earth rotates about its’ polar axis so the
stars make circles around the celestial pole
over the course of a night
Why does the sky change with
your location?
As you move away from the pole your horizon moves with you but the
locations of the celestial poles and celestial equator remains the same
Stuff in Chapter 2
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•
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•
•
•
•
•
•
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
Why does the sky change over
the course of a year?
As we orbit the sun the direction opposite the sun changes and we only see
the stars when the sun is not up
Lecture – Tutorial
Seasonal Stars: pg 7
 Work with a partner!
 Read the instructions and questions carefully.
 Discuss the concepts and your answers with each
other.
 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.