Tully Galaxy Catalog
Tully Galaxy Catalog
| Group Name | Tully |
| Reference | Tully 8,000 km/s Galaxy Catalog (Brent Tully, U Hawaii) The Galaxy Catalog (Zsolt Frei and James E. Gunn) National Optical Astronomical Observatory |
| Prepared by | R. Brent Tully (U Hawaii)
Stuart Levy (NCSA/U Illinois) |
| Labels | Yes |
| Files | tully.speck, tully.label |
| Dependencies | Various images (sgi format) |
| Census | 28,364 galaxies |
The Tully Galaxy Catalog is an extension of the Local Galaxies (local) data group. While local has only about 250 galaxies, the full Atlas has about 30,000 galaxies. The two remain separate because the local data group is more complete than this larger data set and includes smaller, dimmer galaxies.
Many details of the Tully galaxies are described in the local galaxies section. Please see that section for a description of the data variables for this data group.
Size and Scale of the Data
This data group differs from the local galaxies in that it provides coverage over a larger volume of the Universe. The 28,364 points are distributed over about 2.7 x 1025 cubic light-years. The data are distributed in a cube that is about 300 million light-years per side. Because this is all observed data, the Milky Way, of course, lies at the center of this cube. The cube shape of the entire data group is completely arbitrary and has no physical significance.
Colors
The colors of the data points are based on galaxy membership to various structures. All galaxies that belong to dense clusters are colored red. Beyond this, galaxies that belong to a grouping, whether it is a smaller cluster or a strand of galaxies, get one color to signify their membership. For example, the line of galaxies that extend up from the Virgo Cluster (according to our 2-D view in the sky) belong to the Ursa Major Filament and are all colored blue. The galaxies in each structural part of the Universe have received a color based on what element they belong to.
Galactic Census
The following table is equivalent to the census table in the previous section, except we have updated the numbers for the larger data set. Please see an explanation of this table in the previous section.
| Galaxy Morphology Codes and Census | |||
| Number | Hubble Type | Galaxy Type | Census |
| -5 | E | Elliptical | 990 |
| -3 | E/SO | Elliptical/Lenticular (classification uncertain) | 652 |
| -2 | SO | Lenticular | 1439 |
| 0 | SO/a | Lenticular/Spiral | 9132 |
| 1 | Sa | Spiral | 1314 |
| 2 | Sab | Spiral | 1629 |
| 3 | Sb | Spiral | 2046 |
| 4 | Sbc | Spiral | 2332 |
| 5 | Sc | Spiral | 3323 |
| 6 | Scd | Spiral | 2284 |
| 7 | Sd | Spiral | 581 |
| 8 | Sdm | Spiral | 498 |
| 9 | Sm | Spiral/irregular | 311 |
| 10 | Irr | Irregular | 481 |
| 12 | S | Spiral/irregular (classification uncertain) | 0 |
| 13 | P | Peculiar | 0 |
The census reveals the differences between the local data group and this data group. In the local data group, most of the galaxies are irregular, while here irregulars make up fewer than 2% of the total. The bulk of the galaxies in this catalog are spirals. This is just the opposite of the local galaxies, where most of the galaxies are irregular or dwarf galaxies. We cannot see dwarf galaxies out this far, so their numbers are artificially reduced by this observational limitation. The observational bias leans toward the big, bright galaxies, so spirals dominate the population in this data group.
Galaxy Images
Each galaxy in this data group is represented by a point and a polygon. These polygons are properly sized and have an orientation matching that of the galaxy. Placed upon each polygon is an image representing its galaxy type (spiral, elliptical, etc.). Most of these come from The Galaxy Catalog hosted by Princeton.
A handful of images for nearby galaxies were taken from the National Optical Astronomy Observatory (NOAO). These include the Large and Small Magellanic Clouds (NOAO/AURA/NSF), the Andromeda Galaxy or M31 (Bill Schoening, Vanessa Harvey/REU program/NOAO/AURA/NSF), M33 [T.A.Rector (NRAO/AUI/NSF and NOAO/AURA/NSF) and M.Hanna (NOAO/AURA/NSF)], M81 (N.A.Sharp/NOAO/AURA/NSF), M101 (George Jacoby, Bruce Bohannan, Mark Hanna/NOAO/AURA/NSF), M51 (Todd Boroson/NOAO/AURA/NSF), and Centaurus A (Eric Peng, Herzberg Institute of Astrophysics and NOAO/AURA/NSF).
Each of these images has been altered from its original state. Of course, these images were taken from Earth on some of the world's largest telescopes, so foreground stars from our own Galaxy appear in each. We are representing galaxies in extragalactic space, where stars would not appear as large, bright objects. So, we have removed the stars from each image from NOAO.
For a description of the cluster, filament, and void structure in these data, we direct you to the associated tutorials: “Local Large-Scale Structure” and “Tully's Nearby Galaxies.”
© 2002-2005 American Museum of Natural History
Last Modified: 2007-12-19 by Brian Abbott