The Night Sky…last time, The Horizon System

Slides:

Advertisements

Similar presentations

The path of the Moon in the sky

Advertisements

The Sun in the Sky And how it changes in the course of the year.

Geology/Physics 360 Astronomy Chapter 1: The Celestial Sphere.

PHYS 1025 – Introductory Astronomy Lecture 2, Either Semester

Apparent/Actual Motions Summary

Celestial Sphere Stars seem to be on the inner surface of a sphere surrounding the Earth.

Observing and the Sky Astronomy 311 Professor Lee Carkner Lecture 3.

Observing Astronomy 315 Professor Lee Carkner Lecture 3.

Prologue Welcome to PH109 Exploring the Universe Dr. Michael L. Cobb Fall, 2003.

The Earth Rotates.

The Sky From Earth. Let’s Step Outside Where are the stars? What direction are we facing?

Constellations. Celestial Sphere Our Point of View.

The Solar System.

Observing and the Sky Astronomy 311 Professor Lee Carkner Lecture 3.

Lecture 5 – The Night Sky What is the connection between what’s in the book and what’s in the sky?

Motion in the Sky. Discussion How do we estimate how far away things are from us in everyday life?

Patterns in the Sky (cont)

Getting Oriented: Astronomical Coordinate Systems Why are we doing this? Lecture material for next week’s lab Basis for many important technological accomplishments.

Lecture 3 -- Astronomical Coordinate Systems Constellation of the Day…Aquila Look at constellation maps on course home page.

Constellations A constellation is a region of the sky.

Our goals for learning:

AST 112 Motion of Objects in the Sky. The Celestial Sphere Imagine you’re where Earth is, but there’s no Earth. What do you see? Keep in mind: – Nearest.

Introduction to Astronomy.  Observations lead to theories and laws  Laws are concise statements that summaries a large number of observations.  Theories.

The Celestial Sphere Stars at different distances all appear to lie on the celestial sphere. The 88 official constellations cover the celestial sphere.

The sky Our place in space ConstellationsMeasurement Celestial Sphere Polaris and precession $ 200 $ 200$200 $ 200 $ 200 $400 $ 400$400 $ 400$400.

This is what it’s all about…. The Celestial Sphere Useful concept for: 1.Finding your way around the sky (astronomical coordinate system) 2.Thinking about.

Astronomical Coordinates Summary

Sept. 25, Apparent motions: Moon, Sun, stars & Orbits Review the daily (diurnal) vs. monthly (sidereal) sky How about the Moon and its phases? Celestial.

Constellations.

Last time: 2.1. Patterns in The Sky: Stars and constellations, TODAY: celestial coordinates 2.2 Seasons,…Precession 2.2 (cont.) The Moon and Eclipses.

Where is it? On the Celestial Sphere. Longitude and Latitude On Earth: Longitude is how far you are, in degrees, East or West of the “Prime Meridian”

Lines on the sky How the phenomena we see in the sky are linked to the “big picture” in the solar system.

A scientific model.  Why do we use the model of the celestial sphere when studying the night sky, even though it does not accurately represent three-dimensional.

Seasonal Motion. Axis Tilt  Ecliptic The Earth’s rotation axis is tilted 23½° with respect to the plane of its orbit around the sun This means the path.

First announcement: full moon tonight at 12:18 AM.

Announcements Clear sky patrol has not yet started We will start using PRS units this week, make sure that you have one.

Introduction to Positional Astronomy The Night Sky  Nick Devereux 2006.

Mastering Astronomy.

1 Lines in the Sky In order to use the sky to measure time you need to measure the location of objects in the sky. We will look at two methods of measuring.

Getting Oriented: Astronomical Coordinate Systems Why are we doing this? Lecture material for next week’s lab Basis for many important technological accomplishments.

EARTH IN SPACE. A reminder about earth  The earth is almost a sphere  We locate points on the sphere with 3 coordinates – Longitude (180º W º.

Celestial Navigation Celestial Motion 1. General Organization Original “celestial sphere” model devised by the Greeks is still used –Greeks saw the Earth.

Chapter 1 Charting the Heavens: The Foundations of Astronomy.

The Daily Motion As the Earth rotates, the sky appears to us to rotate in the opposite direction. The sky appears to rotate around the N (or S) celestial.

1.Stars move from east to west over the course of the night 2.Change slightly from one night to the next 3.However, their relative positions remain.

Constellations come, and climb the heavens, and go, And thou dost see them rise, Star of the Pole! and thou dost see them set, Alone,

Unit I - Lesson I “Foundations of Astronomy” Astronomy.

Seasonal Motion. Daily and yearly motion intertwined Solar vs Siderial Day –Earth rotates in 23 h 56 m –also rotates around sun  needs 4 min. to “catch.

Chapter 2 Celestial Motions. Fig. 2.1 The Celestial Sphere To understand the idea of the celestial sphere first think of the earth in space. The stars.

Daily and yearly motion intertwined Solar vs Siderial Day –Earth rotates in 23 h 56 m –also rotates around sun  needs 4 min. to “catch up” Consequence:

AstroLab-2 Locating Stars in the Sky Merav Opher-Fall 2004.

MOTIONS OF SKY. Goals To identify the different parts of the celestial sphere model To understand how to express the location of objects in the sky To.

Chapter 4: Rising & Setting Stars © BRIEF

Observational Astronomy Mapping the Heavens Coordinate Systems We have two different ways to locate objects in the sky: Celestial equatorial system -Right.

The equatorial coordinate system a system like latitude and longitude for the celestial sphere.

Motion in the Sky. Discussion What is a year? Discussion What is a day?

Lecture 3 -- Astronomical Coordinate Systems Constellation of the Day…Aquila constellations.

Phases of the Moon Lab The Celestial Sphere Model One way the celestial sphere model is used explains positions in the sky as seen from YOUR position.

The Celestial Sphere Model describing the sky. (Glass bowl over the Earth) Pretend that the stars are attached to it Celestial Meridian: Line North to.

Goal: To understand the very basics of Astronomy. Objectives: 1)To understand how the night sky is set up 2)To be familiar with some useful Astronomy terms.

Research Experiences for Undergraduates (REU)

The Appearance of the Night Sky

Rotating Earth Sunlight animations © Swinburne.

Motions in the sky: The celestial sphere

I think: ______________

Celestial Motions Chapter 2.

The Sky (Celestial Sphere)

ASTRO UNIT 1 REVIEW.

Celestial Motions Chapter 2.

Astronomy notes for Phys/Geog 182

Presentation transcript:

The Night Sky…last time, The Horizon System The Sun rises in the east, transits, sets in the west. The Moon…. The stars …. The moon changes position against the stars from night to night The sky changes with the seasons (“parade of the constellations”) ?

“Different Seasons, Different Constellations” The Earth orbits the Sun We see the Sun projected against background stars Earth moves in a plane, Sun projected onto a line on the sky

The Moon and the major planets also move along the celestial line (ecliptic or zodiac) This demonstrates and important fact: major solar system bodies are orbiting the Sun in the same plane Astronomical basis for the origin of astrology

Seasonal Variations in the Position of the Sun (back in horizon system)

Explanation of Seasonal Variations: tilt of the Earth’s axis: obliquity of the ecliptic

Obliquity of the Ecliptic and the Altitude Angle of the Sun

Two Lines on the Sky The ecliptic The celestial equator See Figure 2.4

Conclusion: seasons are due to tilt of Earth’s axis and motion of Earth about the Sun Not changing distance between the Earth and Sun

A New Coordinate System: Celestial Coordinates The stars “stick together” and define their own reference system. The planets move with respect to them Celestial coordinates are Right Ascension and Declination Right Ascension ….. Longitude Declination ….latitude http://sohowww.nascom.nasa.gov/ See SC1 chart for illustration

Map of the Sky