Imaging instrumentation

Nature of science:

Improved instrumentation: The optical telescope has been in use for over 500 years. It has enabled humankind to observe and hypothesize about the universe. More recently, radio telescopes have been developed to investigate the electromagnetic radiation beyond the visible region. Telescopes (both visual and radio) are now placed away from the Earth’s surface to avoid the image degradation caused by the atmosphere, while corrective optics are used to enhance images collected at the Earth’s surface. Many satellites have been launched with sensors capable of recording vast amounts of data in the infrared, ultraviolet, X-ray and other electromagnetic spectrum ranges. (1.8)

• Optical compound microscopes
• Simple optical astronomical refracting telescopes
• Simple optical astronomical reflecting telescopes
• Single-dish radio telescopes
• Radio interferometry telescopes
• Satellite-borne telescopes

Applications and skills:

• Constructing and interpreting ray diagrams of optical compound microscopes at normal adjustment
• Solving problems involving the angular magnification and resolution of optical compound microscopes
• Investigating the optical compound microscope experimentally
• Constructing or completing ray diagrams of simple optical astronomical refracting telescopes at normal adjustment
• Solving problems involving the angular magnification of simple optical astronomical telescopes
• Investigating the performance of a simple optical astronomical refracting telescope experimentally
• Describing the comparative performance of Earth-based telescopes and satellite-borne telescopes

• The use of the radio interferometry telescope crosses cultures with collaboration between scientists from many countries to produce arrays of interferometers that span the continents

Theory of knowledge:

• However advanced the technology, microscopes and telescopes always involve sense perception. Can technology be used effectively to extend or correct our senses?

Utilization:

• Cell observation (see Biology sub-topic 1.2)
• The information that the astronomical telescopes gather continues to allow us to improve our understanding of the universe
• Resolution is covered for other sources in Physics sub-topic 9.4

• Simple optical astronomical reflecting telescope design is limited to Newtonian and Cassegrain mounting
• Radio interferometer telescopes should be approximated as a dish of diameter equal to the maximum separation of the antennae
• Radio interferometry telescopes refer to array telescopes

Data booklet reference:

• Aim 3: images from microscopes and telescopes both in the school laboratory and obtained via the internet enable students to apply their knowledge of these techniques
• Aim 5: research astronomy and astrophysics is an example of the need for collaboration between teams of scientists from different countries and continents
• Aim 6: local amateur or professional astronomical organizations can be useful for arranging demonstrations of the night sky