Astronomy: images of the Universe

Modern astronomy utilises a range of techniques across the electromagnetic spectrum that allow astronomers to measure the brightness, size and shape of astronomical objects, as well as their structure in many cases. This free course enables you to explore multiwavelength images of the Universe and make your own measurements of stars, nebulae and galaxies using online tools and databases. You will explore the different types of nebulae in the Messier catalogue, considering their sizes and distances using an interactive Scales tool, and use a web tool called Chromoscope to survey the Milky Way in different wavebands.This free course is an adapted extract from the Open University course S284 Astronomy.

• 1 Images and measurements
• 1.1 Understanding brightness
• 1.2 Measuring brightness
• 1.3 Measuring sizes
• 1.4 Measuring shapes
• 2 Structure in images
• 2.1 From point-like stars to diverse nebulae
• 2.2 Exploring the Messier catalogue
• 2.3 Types of extended objects
• 3 Colour in astronomy images
• 3.1 Broadband images
• 3.2 Multiwavelength images
• 3.3 Narrow-band images
• 4 Mapping the sky
• 4.1 The Milky Way and the Galactic plane
• 4.2 Surveying beyond the Milky Way
• 4.3 Surveying the variable Universe