ACTIVITY 1: INTRODUCTION TO ASTRONOMYAstronomy is the scientific study of celestial objects — e.g. Planets, Stars, Galaxies, and the Universe as a whole.Astronomy tools - telescopes, spacecraft, internet, computers, laboratoriesMoon phases repeat in about a month because the moon's orbital period about the earchThe moon can only be full (or close to it) because if it is high int he skyu at midnight it is roughly opposite wherethe sun is and so will be fully illuminatedWhen venus is at a full phase how are the venus, eartha dn sun positioned, in line with venus and earth onopposite sides of the sun.AstrophysicsThe study of the physics of celestial objects. These days the bulk of astronomy isastrophysics and most professional astronomers would also considerthemselves astrophysicists.AstrobiologyThe study of the origin, evolution and distribution of life in the universe. This isa relatively recently introduced term, and something that we will be studying inparticular in this course.AstrometryThe science of measuring the positions of celestial objects such as stars andplanets. Positions can be measured to great accuracy and provide valuableinformation about the motions of the objects in the solar system and galaxy.Astrometry is a technique used within astronomy and astrophysics.AstronauticsThis is the study of space flight. It is a branch of engineering (compare with theterm Aeronautics).Ancient Greek Astronomy●Geocentric Model●Earth centre and concentric spheres carrying the sun, moon and planets, and an outers●1.4 Ptolemaic System: catalogue of stars, believed to be based on the earlier work of Hipparchus, model for theplanetary motions which is based on the geocentric model, and an even more elaborate system of circles oncircles (or "epicycles"). Tables predicting the positions of the Sun, Moon and Planets which at that time were thebest available.
