![[click for GIF movie]](movie0.gif)
![[side on veiw of velocity axis]](fornax_030.gif)
Click on the image to see the cube rotate in 3D
(1.5 MByte gif image).
axis is velocity, increasing from about 400 km/s on the right to 3700 km/s on the left. The vertical axis is RA, increasing from about RA 02:40:00 to RA 04:20:00.
|
|
|
|
Face-on view of the Fornax mosaic cube, with RA on the horizontal axis and Declination on the vertical axis. Click on the image to see the cube rotate in 3D (1.5 MByte gif image). |
Side view of the Fornax mosaic cube. The horizontal axis is velocity, increasing from about 400 km/s on the right to 3700 km/s on the left. The vertical axis is RA, increasing from about RA 02:40:00 to RA 04:20:00. |
This movie is of a mosaic of 10 standard HIPASS survey cubes, covering a region on the sky 26 x 26 degrees in size, (about 9 Mpc across at the distance of Fornax). The third dimension is velocity, in which each galaxy appears as an elongated blob along the velocity dimension. The velocity range here is about 400 to 3700 km/s, corresponding to a maximum distance of about 55 Mpc. The Fornax Cluster is about 20 Mpc away at a mean velocity of 1400 km/s. The optical extent of the cluster is about 5 degrees across, just the very centre of this field. When the movie shows the "side on" view of this large cube you can see that the Fornax Cluster is part of a much larger sheet of galaxies all at about the same distance. Many of the cluster galaxies seen in optical surveys contain very little HI and are not detected in 21cm radio surveys such as HIPASS.
