Void (astronomy)
In astronomy, voids are the empty spaces between filaments, the largest-scale structures in the Universe, that contain very few, or no, galaxies. Voids typically have a diameter of 11 to 150 Mpc; particularly large voids, defined by the absence of rich superclusters, are sometimes called supervoids. Voids located in high-density environments are smaller than voids situated in low-density spaces of the universe.[1]
List of voids
Supervoids
A 1994 census lists a total of 27 supervoids with a distance of up to 740 Mpc.[2]
| # | Name | Distance (h-1Mpc)[3] | Diameter (h-1Mpc)[4] |
|---|---|---|---|
| 1 | 134 | 88 | |
| 2 | 207 | 96 | |
| 3 | 216 | 72 | |
| 4 | 241 | 86 | |
| 5 | 129 | 92 | |
| 6 | 236 | 72 | |
| 7 | 248 | 100 | |
| 8 | 201 | 76 | |
| 9 | Southern Local Supervoid | 96 | 112 |
| 10 | 246 | 144 | |
| 11 | 160 | 92 | |
| 12 | 227 | 106 | |
| 13 | 246 | 94 | |
| 14 | 167 | 68 | |
| 15 | 241 | 98 | |
| 16 | 222 | 74 | |
| 17 | 216 | 94 | |
| 18 | 119 | 102 | |
| 19 | 119 | 108 | |
| 20 | Boötes void (Great Void) |
216 | 78 |
| 21 | 143 | 116 | |
| 22 | 246 | 96 | |
| 23 | 219 | 72 | |
| 24 | Northern Local Supervoid | 61 | 104 |
| 25 | 198 | 74 | |
| 26 | 246 | 80 | |
| 27 | 241 | 70 |
Not shown in the above chart:
- Capricornus Void
- The claimed Eridanus Supervoid or "Great Void", reported on 24 August 2007 by the NRAO from Very Large Array Sky Survey data.[5] This void, if real, would be much larger than the others listed here, being about 300 h-1Mpc in diameter and 1800–3000 h-1 Mpc distant. It would be associated with (and be the explanation of) a cold spot in the cosmic microwave background at the sky location.
The evidence for such a "Great Void" is disputed by Smith and Huterer.[6] They showed that the claims made of observational evidence for such a void from survey data neglected systematic effects, and did not account for a posteriori choices made in analyzing data.
Voids
| Name | Dimensions | Location | Data | Notes |
|---|---|---|---|---|
| Eridanus void | This void is separated from the Sculptor void by a sheet of galaxies. [7] | |||
| Microscopium void | A hole in the distribution of galaxies separating Sculptor and Microscopium voids the size of (redshift) 1250km/s appears to exist. This is roughly 1/2 of Microscopium's diameter. [7] | |||
| Sagittarius void | ||||
| Sculptor void | This void is separated from the Eridanus void by a sheet of galaxies. A hole in the distribution of galaxies separating Sculptor and Micrsocopium voids the size of (redshift) 1250km/s appears to exist. A hole in the distribution of galaxies separating Sculptor and Southern Eridanus voids the size of (redshift) 1250km/s appears to exist. [7] | |||
| Southern Eridanus void | The Southern Eridanus void is connected to the Eridanus void by a hole in the distribution of galaxies separating the two. A hole in the distribution of galaxies separating Sculptor and Southern Eridanus voids the size of (redshift) 1250km/s appears to exist. [7] |
Map
See also
External links
- Universe family tree: Void
- a few animated views of voids and their distribution from Hume Feldman with Sergei Shandarin, Dept. Physics and Astronomy, University of Kansas, Lawrence, KS, USA.
- Visualization of Nearby Large-Scale Structures Fairall, A. P., Paverd, W. R., & Ashley, R. P. Bibcode:1994ASPC...67...21F
References
- ^ U. Lindner, J. Einasto, M. Einasto, W. Freudling, K. Fricke, E. Tago (1995). The Structure of Supervoids I: Void Hierarchy in the Northern Local Supervoid "The structure of supervoids. I. Void hierarchy in the Northern Local Supervoid". Astron. Astrophys. 301: 329.
{{cite journal}}: Check|url=value (help)CS1 maint: multiple names: authors list (link) - ^ Einasto, M (1994-07-15), "The Structure of the Universe Traced by Rich Clusters of Galaxies", Monthly Notices of the Royal Astronomical Society, 269
- ^ To the center of the void
- ^ This is the diameter of the largest sphere one can describe inside the void that contains no superclusters. Some voids have an elongated shape, so this diameter may underrepresent the size of some voids.
- ^ "Astronomers Find Enormous Hole in the Universe". National Radio Astronomy Observatory Press release, retrieved 24 August 2007.
- ^ [1] "No evidence for the cold spot in the NVSS radio survey," Kendrick Smith and Dragan Huterer (2008).
- ^ a b c d Astronomy and Astrophysics, vol. 229, no. 1, March 1990, p. 75-79. ; "A two-dimensional sheet of galaxies between two southern voids" ; 03/1990 ; ISSN 0004-6361 ; Bibcode:1990A&A...229...75M
