Astronomy with an online telescope
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Contents

  • Introduction and guidance
    • Telescope upgrade 2021
    • What is a badged course?
    • How to get a badge
  • Introduction
  • 1 Finding your way around the sky using Stellarium software
    • 1.1 Installing Stellarium and getting started
    • 1.2 Setting your location
    • 1.3 Controlling how Stellarium displays the sky
  • 2 The apparent motion of objects in the night sky
    • 2.1 Our changing view of the sky
    • 2.2 First observations from Tenerife – the All-Sky camera
    • 2.3 Using Stellarium to understand the apparent motion of the sky
    • 2.4 Understanding how the sky changes with the seasons
  • 3 Mapping the night sky
    • 3.1 Two coordinate systems
    • 3.2 The Altitude-Azimuth system
    • 3.3 Equatorial celestial coordinates – right ascension and declination
    • 3.4 Using equatorial coordinates to locate objects
  • 4 This week’s quiz
  • 5 Summary of Week 1
  • Introduction
  • 1 Observing with the naked eye
    • 1.1 Understanding dark adaptation
    • 1.2 Testing your own dark adaptation
    • 1.3 Observing the night sky with dark-adapted eyes
  • 2 Observing with optical instruments
    • 2.1 Binoculars
    • 2.2 Telescopes
  • 3 Observing from the Earth
  • 4 The COAST facility
  • 5 This week’s quiz
  • 6 Summary of Week 2
  • Introduction
  • 1 Brightness of the stars
    • 1.1 The magnitude scale
    • 1.2 Exploring the magnitude scale
    • 1.3 Estimating magnitudes by comparing stars
  • 2 Magnitude limits
    • 2.1 Magnitude limits and choice of observing site
    • 2.2 Estimating magnitudes from an image
  • 3 Your limits
  • 4 This week’s quiz
  • 5 Summary of Week 3
  • Introduction
  • 1 Messier objects
    • 1.1 The Messier catalogue
    • 1.2 The different types of Messier objects
    • 1.3 Messier objects in Stellarium
  • 2 Requesting your first image
    • 2.1 Planning your observations
    • 2.2 Register with COAST
    • 2.3 Requesting an image from COAST
  • 3 Collecting your first image
  • 4 This week’s quiz
  • 5 Summary of Week 4
  • Introduction
  • 1 Continue observing with COAST
  • 2 The Sun as an ordinary star
    • 2.1 The Sun – some facts and figures
    • 2.2 The energy output of the Sun
    • 2.3 The mass, composition and structure of the Sun
    • 2.4 The age of the Sun
    • 2.5 Summary – properties of the Sun
  • 3 What powers the Sun and stars?
    • 3.1 The most famous equation in the world
    • 3.2 Nuclear fusion – the source of the Sun’s energy
    • 3.3 Estimating the Sun’s lifetime
    • 3.4 Midweek summary
  • 4 Comparing the Sun with other stars
  • 5 This week’s quiz
  • 6 Summary of Week 5
  • Introduction
  • 1 Refine and edit your COAST images
  • 2 Classifying stars – the Hertzsprung-Russell diagram
    • 2.1 The differing colours of stars
    • 2.2 Building the HR diagram
    • 2.3 Understanding the main sequence
  • 3 The masses of stars
    • 3.1 Measuring the masses of stars
    • 3.2 How the mass of a star affects its luminosity
  • 4 The lifecycles of stars
    • 4.1 The main sequence
    • 4.2 Stellar lifetime as a function of mass
    • 4.3 After the main sequence
  • 5 This week’s quiz
  • 6 Summary of Week 6
  • Introduction
  • 1 Stellar evolution after the main sequence
    • 1.1 Helium as a nuclear fuel
    • 1.2 Expansion and the red giant branch
    • 1.3 Tracks on the HR diagram
    • 1.4 The instability strip
  • 2 Variable stars
    • 2.1 Pulsating variables and their light curves
    • 2.2 Eclipsing variables
    • 2.3 Supernovae and cataclysmic variables
  • 3 Collaboration in observing
  • 4 Plan your own variable star observations using COAST
  • 5 This week’s quiz
  • 6 Summary of Week 7
  • Introduction
  • 1 Retrieving your images
    • 1.1 File formats
    • 1.2 Save images in FITS format
  • 2 Measuring the brightness of your variable star
    • 2.1 Aperture photometry
    • 2.2 Reference stars
    • 2.3 Using finder charts to identify target and reference stars
    • 2.4 Aperture photometry
  • 3 Building the light curve
    • 3.1 View your results on the light curve
    • 3.2 Interpreting the light curve
    • 3.3 Request further images
  • 4 This week’s quiz
  • 5 Summary of Week 8
  • 6 Concluding thoughts
    • Tell us what you think
  • References
  • Acknowledgements

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