Spectroscopy: Unlocking the Secret in Starlight
Spectroscopy is a key tool in astronomy. By obtaining and analysing the spectrum from a distant object astronomers can identify what type of object it is and determine a wealth of characteristics for the object. These include its effective temperature, how fast it is rotating and whether it is moving towards or away from us, how large and dense it is and what it is made of. Within the last decade planets beyond our Solar System have been discovered via their effect on the parent star's spectrum.
![Continuous spectrum](/outreach//education/senior/astrophysics/images/spectra/continuumstrip.jpg)
Syllabus Requirements
3. Spectroscopy is a vital tool for astronomers and provides a wealth of information
- account for the production of emission and absorption spectra and compare these with a continuous black body spectrum
- describe the technology needed to measure astronomical spectra
- identify the general types of spectra produced by stars, emission nebulae, galaxies and quasars
- describe the key features of stellar spectra and describe how these are used to classify stars
- describe how spectra can provide information on surface temperature, rotational and translational velocity, density and chemical composition of stars
- perform a first-hand investigation to examine a variety of spectra produced by discharge tubes, reflected sunlight, or incandescent filaments
- analyse information to predict the surface temperature of a star from its intensity/wavelength graph
Physics Stage 6 Syllabus © Copyright 2002 The State of New South Wales (Board of Studies).