Spectroscopy

Spectrum of the Sun

Spectroscopy

Spectroscopy is a technique used to analyse light by breaking it apart into its component colours with a prism or grating and studying the resulting pattern, which is known as a spectrum. Dark absorption and bright emission lines that interrupt the rainbow of colours from the split-apart light allow scientists to 'fingerprint' the light's source.

By studying a star's spectrum, scientists can work out its chemical make-up and temperature. Spectroscopy also allows astronomers to work out the relative velocities of galaxies and supernovae by measuring something called red shift.

Image: A spectrum of the Sun (credit: Physics dept., Imperial College/SPL)

Watch and listen to clips from past programmes TV clips [8]

Spectrum of the Sun

Introduction

A powerful technique helps scientists 'fingerprint' starlight.

About Spectroscopy

Spectroscopy /spɛkˈtrɒskəpi/ is the study of the interaction between matter and radiated energy. Historically, spectroscopy originated through the study of visible light dispersed according to its wavelength, by a prism. Later the concept was expanded greatly to comprise any interaction with radiative energy as a function of its wavelength or frequency. Spectroscopic data is often represented by a spectrum, a plot of the response of interest as a function of wavelength or frequency.

Read more at Wikipedia

This entry is from Wikipedia, the user-contributed encyclopedia. If you find the content in the 'About' section factually incorrect, defamatory or highly offensive you can edit this article at Wikipedia.

BBC © 2014 The BBC is not responsible for the content of external sites. Read more.

This page is best viewed in an up-to-date web browser with style sheets (CSS) enabled. While you will be able to view the content of this page in your current browser, you will not be able to get the full visual experience. Please consider upgrading your browser software or enabling style sheets (CSS) if you are able to do so.