Expo/Science & Industry/Whispers From the Cosmos

| Back | Up | Map | Glossary | Information |

Average Image

An average image is just that: an image produced by averaging all the channel maps together. Using the same spatial coordinate system, right ascension and declination, as channel maps, average images present an enhanced way to show the spatial distribution of material within an object. Although channel maps contain velocity information, average images do not; for it is lost in the averaging process.

This average image of M82 is a good representation of the shape and extent of the carbon monoxide gas within M82.

Bima Consortium

JPEG (23K)

The same can be shown in a contour map as well:

Bima Consortium

JPEG (21.5K)

Again, as with channel maps, the observed intensity is indicated by either a color code on a radiomap where the brightness represents the observed intensity, or by contours on a contour map where each contour represents a certain observed intensity value.

Return to Insight Through Images
Up to Computers: The Image Forming Elements

Exhibit Map
Glossary
Information Center

Copyright © 1995: Board of Trustees, University of Illinois

NCSA. Last modified, 11/13/95