Helioseismology - depends on the temperature, density, and...

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
Helioseismology Another probe of the Sun's interior uses the pulsating motions of the Sun. The pulsations are too small to be seen just by looking at the Sun. But the pulsations can be seen if the doppler shifts are measured across the face of the Sun. Some parts of the Sun expand towards the Earth and adjacent regions contract away from the Earth. These regions are several thousands of kilometers across and the pulsation periods are just a few minutes long. Different types of oscillating waves combine to produce the complicated patterns of pulsation seen. One type of pulsation is shown here. The blue regions are approaching and the red regions are receding from you. The pulsations are thought to extend far into the Sun's interior (courtesy of the National Solar Observatory ). If you disentangle the different oscillation modes from each other, you can use these waves to probe the solar interior. How those waves propagate through the Sun and interact with each other
Background image of page 1
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: depends on the temperature, density, and composition of the material they pass through. By observing the effects of these waves on the photosphere of the Sun, you can determine the temperature, density, and composition of the different layers inside the Sun. Geologists on the Earth use similar techniques to study the interior of our planet from earthquake waves in the research field called seismology. Modifying the name for solar studies, the study of the Sun's interior using the solar oscillations is called helioseismology . Solar astronomers have set up a global network of stations to continuously monitor the Sun's pulsations. This network is called the Global Oscillations Network Group (GONG). Links to web sites describing GONG and other helioseismology sites are given below. Instruments to detect solar oscillations have also been placed on satellites. Check the links below for more information about them....
View Full Document

Ask a homework question - tutors are online