Unit 5, Topic 1For Our Eyes Only

Frame of ReferenceA frame of reference is a set of

axes of any kind that is used to describe the positions or motions of things.Latitude and longitudeMap coordinates

Basic Grade 6 Review – do not copyCelestial bodies , Constellations,

planetsOn each successive day, a given

star rises and sets four minutes earlier than the day before.

Sky Co-ordinatesAzimuth - the first angle is

measured clockwise from north.Altitude - measure the celestial

body’s angle above the horizon in degrees.

These are the altitude-azimuth co-ordinates.

Sky Co-ordinatesAn astrolabe is a device used to

measure the altitude of an object.A compass is used to measure an

object’s azimuth.

1. Look directly to the left (west). Max height is 90° - which star is about halfway up the sky? A

Astrolabe

The Earth-Centred ModelAncient peoples still

believed that the stars circle around Earth.

This led to an Earth-centred or geocentric model of the universe.

Ptolemy’s ModelPtolemy changed

Aristotle’s Earth-centred model. He added the idea of epicycles in an attempt to make Aristotle’s model work.

The Sun-Centred ModelNicholas Copernicus proposed a

sun-centered view. He thought that the Sun was the

centre of our solar system and all planets went around the sun.

The Sun-Centred ModelGalileo confirmed Copernicus’

model.He made improvements to the

telescope and was able to show that Copernicus was correct.

Brain Pop Galileo Galilei

The Sun-Centred ModelThis is known as the Sun-centred

or heliocentric model of the universe.

Moon is 140° from north. That is the azimuth.

Moon is 30° from the horizon – that is the altitude.