| Back | Up | Map | Glossary | Information |
Caption and Credits
This movie presents a series of channel maps of M82 one after the other, according to the velocities of gas. However, it is important to grasp that as the animation plays, it is not depicting time-dependent evolution as such; rather the animation is stepping through each of the velocities for which the channel maps were constructed.
The first channel map shows the distribution of carbon monoxide (CO) gas moving at the slowest velocity. The next channel map at a slightly greater velocity and so on. Thus the movie offers a means to quickly compare all the channel maps in rapid successi on.
The velocities here refer to the motion of CO gas towards or away from Earth only, not across the sky. To determine the full range of motion of the CO gas, astronomers look at how its radial velocity changes across M82. Notice the brightly emitting materi al that appears to travel across the movie frame as the animation unfolds. This pattern indicates that the position of the gas in M82 is changing. Spectral line graphs reveal that the gas is rotating clockwise, with the plane of ro tation facing us edge-on.
Back to Insight through Images
Up to Computers: The Image Forming Elements