In the night sky: Orion

From the basics of astronomy and stargazing, to the science behind the birth of a star, this four-week course will change the way you see the night sky. You’ll examine one of the most famous constellations, Orion, who the Ancient Greeks believed was a huntsman placed among the stars by Zeus himself.Starting with its famous nebula where new stars and planets are being formed, you’ll take a look at the seven brightest stars that make up this constellation, including the supergiants Rigel and Betelgeuse, using high-quality images from telescopes such as the Hubble Space Telescope.You’ll find out about exoplanets, planets that orbit other stars just as we orbit the Sun and may hold the secrets to life outside of the solar system. Finally you’ll think about the Milky Way, the galaxy of which our solar system is but one small part, and consider the history of the universe from the Big Bang to the present.RequirementsYou do not need a professional telescope for this course, but you may find at least a pair of binoculars extremely useful.No prior experience of the subject is required.This OpenLearn science course is produced with the kind support of Dangoor Education, the educational arm of The Exilarch's Foundation.

• Week1Week 1: Beginning the journey
• Introduction
• 1.1 Map of the night sky
• 1.1.1 Meeting Orion
• 1.1.2 Where is Orion?
• 1.1.3 Finding Orion
• 1.1.4 Who was Orion?
• 1.2 What are constellations?
• 1.2.1 Patterns in the sky
• 1.2.2 Orion in 3D
• 1.2.3 Moving constellations
• 1.2.4 Signs of the Zodiac
• 1.2.5 Name a constellation
• 1.2.6 Navigating by the stars
• 1.2.7 Finding your longitude
• 1.3 Mapping the stars
• 1.3.1 Gaia mission
• 1.3.2 Behind the scenes with Gaia
• 1.4 Week 1 quiz
• Summary of Week 1
• Further reading
• Acknowledgements
• Week2Week 2: Travelling from star birth to star death
• Introduction
• 2.1 What is a star?
• 2.1.1 Luminosity of a star
• 2.1.2 What is a nebula?
• 2.1.3 How far away is the Orion nebula?
• 2.1.4 Size of a nebula
• 2.1.5 Trapezium cluster
• 2.1.6 Birth of a star
• 2.1.7 The Orion nebula
• 2.1.8 Protostar
• 2.1.9 Photographing Orion
• 2.2 The life of a star
• 2.2.1 Types of star
• 2.2.2 Mass, luminosity and temperature
• 2.2.3 Nuclear fusion
• 2.3 The death of a star
• 2.3.1 Planetary nebula
• 2.3.2 Supernovae
• 2.3.3 Beautiful supernovae
• 2.3.4 Cosmic onion
• 2.3.5 Supergiant stars
• 2.3.6 Exploding supernova
• 2.3.7 The final remnants
• 2.3.8 Neutron stars
• 2.3.9 Black holes
• 2.3.10 Black hole cannibal
• 2.4 Week 2 quiz
• Summary of Week 2
• Acknowledgements
• Week3Week 3: From the beginning
• Introduction
• 3.1 The Big Bang
• 3.1.1 Open or closed universe
• 3.1.2 Particle formation
• 3.1.3 Evidence of expansion
• 3.1.4 Hubble Ultra Deep Field
• 3.1.5 Photographing Orion
• 3.2 What is a galaxy?
• 3.2.1 Different types of galaxy
• 3.2.2 Merging galaxies
• 3.2.3 Colliding and merging galaxies
• 3.2.4 Galaxies gone wild!
• 3.2.5 The Milky Way
• 3.2.6 The Local group
• 3.2.7 Galaxy Zoo
• 3.2.8 Dark matter
• 3.2.9 Dark energy
• 3.3 The electromagnetic spectrum
• 3.3.1 Objects at different wavelengths
• 3.3.2 Observing the stars
• 3.3.3 Telescopes in space
• 3.3.4 Behind the scenes with Monica Grady
• 3.4 Week 3 quiz
• Summary of Week 3
• Further reading
• Acknowledgements
• Week4Week 4: Our place in the Universe
• Introduction
• 4.1 Habitable zone
• 4.1.1 The right type of star
• 4.1.2 Lifetime of a star
• 4.1.3 The right type of galaxy
• 4.1.4 Where we are
• 4.1.5 Photographing Orion
• 4.2 Protoplanetary discs
• 4.2.1 Protoplanetary disc formation
• 4.2.2 Collapse of a nebula
• 4.2.3 Planetesimals
• 4.2.4 The Solar System
• 4.2.5 The asteroid belt
• 4.2.6 Comets
• 4.2.7 Philae lander
• 4.2.8 A comet’s tail
• 4.2.9 Where do comets come from?
• 4.3 What is an exoplanet?
• 4.3.1 Exoplanet encyclopedia
• 4.3.2 Planet hunting – identification and observing techniques
• 4.3.3 Gliese 581
• 4.3.4 Transit experiment
• 4.3.5 Other information from transits
• 4.3.6 Protoplanetary disc example
• 4.3.7 Life beyond the Solar System
• 4.4 Week 4 quiz
• End-of-course summary
• Tell us what you think
• Where next?
• Acknowledgements