This is a list of voids in astronomy. Voids are particularly galaxy-poor regions of space between filaments, making up the large-scale structure of the universe. Some voids are known as supervoids.
In the tables, z is the cosmological redshift, c the speed of light, and h the dimensionless Hubble parameter, which has a value of approximately 0.7 (the Hubble constant H0 = h × 100 km s −1 Mpc−1). Mpc stands for megaparsec.
The co-ordinates (right ascension and declination) and distance given refer to the approximate center of the region.
Name | Coordinates | Distance | Diameter | Data | Notes |
---|---|---|---|---|---|
Local Void | 18h 38m+18° | cz=2500 km/s | 60 Mpc | [1] | |
Northern Local Supervoid | 61 Mpc | 104 Mpc | Virgo Supercluster, Coma Supercluster, Perseus–Pisces Supercluster, Ursa Major–Lynx Supercluster, Hydra–Centaurus Supercluster, Sculptor Supercluster, Pavo–Corona Australes Supercluster form a sheet between the Northern Local Supervoid and the Southern Local Supervoid. [2] The Hercules Supercluster separates the Northern Local Void from the Boötes Void. [2] The Perseus–Pisces Supercluster and Pegasus Supercluster form a sheet separating the Northern Local Void and Southern Local Void from the Pegasus Void. [2] | ||
Southern Local Supervoid | 96 Mpc | 112 Mpc | |||
Giant Void | 13h 01m+38.7° | z=0.116 | 300-400 Mpc | "Giant Void in NGH" or "AR-Lp 36"; NGH stands for "Northern Galactic Hemisphere"; discovered in 1988. [3] It is the largest void in the NGH where z<0.14. [4] | |
KBC Void | 600 Mpc | Void containing the Milky Way and Local Group [5] |
Name | Coordinates | Distance | Diameter | Data | Notes |
---|---|---|---|---|---|
Boötes Void (Great Void) | 14h 20m26° | 150 Mpc | 100 Mpc | The Hercules Supercluster separates the Northern Local Void from the Boötes Void. [2] The Hercules Supercluster thus forms part of the near edge of the Boötes Void. [8] | |
Canis Major Void | |||||
Columba Void | |||||
Coma Void | Discovered in 1975, along with the Coma Supercluster, it lies in front of the Coma Cluster. [9] It was the first void to be discovered and is approximately 1/3 as far away as the much larger Boötes Void. [10] | ||||
Corona Borealis Void | |||||
Eridanus Void | This void is separated from the Sculptor void by a sheet of galaxies. [11] | ||||
Eridanus Supervoid (Great Void) | 03h 15m 05s−19° 35′ 02″ | z=1 | 150 Mpc | The claimed Eridanus Supervoid or "Great Void", reported on 24 August 2007 by the NRAO from Very Large Array Sky Survey data. [12] This void, if real, would be much larger than the others listed here (except the Giant Void), about 300 h−1 Mpc in diameter and 1800–3000 h−1 Mpc distant (where h is the dimensionless Hubble parameter). 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. [13] 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. | |
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) 1250 km/s appears to exist. [11] | ||||
Fornax Void | |||||
Hercules Void | 15.5h+30° | cz=7000 km/s | 3100 km/s | [14] Discovered in 1979 [8] [15] | |
Hydra Void | The Hydra Void lies beyond the Hydra–Centaurus Supercluster [16] | ||||
Leo Void | 11h 30m0° | cz=4000 km/s | [16] | ||
Microscopium Void | A hole in the distribution of galaxies separating Sculptor and Microscopium voids the size of (redshift) 1250 km/s appears to exist. This is roughly 1/2 of Microscopium's diameter. [11] | ||||
Ophiuchus Void | near 17h−25° | < 5000 km/s (the outer limit) | perhaps 0–5000 km/s | 25% of average universe density is the void density of matter. The far end of this void is defined by the Ophiuchus Supercluster. [17] | |
Pegasus Void | 22h+15° | cz=5500 km/s | 40 Mpc | [18] The Perseus–Pisces Supercluster and Pegasus Supercluster form a sheet separate the Northern Local Void and Southern Local Void from the Pegasus Void. [2] | |
Perseus–Pisces Void | 1h+10° | cz=8000 km/s | 3000 km/s | Discovered in 1980, [15] it is also called the Perseus Void | |
Sagittarius Void | |||||
Sculptor Void | 23h 48m−24° 39′ | 34.8 Mpc/h | Corresponds to SRSS1 Void 3 and SRSS2 Void 5 [19] This void is separated from the Eridanus Void by a sheet of galaxies. A hole in the distribution of galaxies separating Sculptor and Southern Eridanus Voids the size of 1250 km/s appears to exist. [11] The Sculptor Void lies next to the Southern Wall or Southern Great Wall. | ||
Taurus Void | 30 Mpc | The Taurus Void appears large and circular, and has walls of galaxies surrounding it. It lies next to the Perseus–Pisces Supercluster, and is the most visually identifiable. Several galaxies have been found to reside in the void, such as UGC 2627 and UGC 2629, both approximately 185 million light years away. [20] | |||
[6] [7] |
Designation | Location | Coordinates | Distance | Diameter | Dimensions | Notes |
---|---|---|---|---|---|---|
Bahcall & Soneira 1982 void | z = 0.03 – 0.08 |
| [21] This suspected void ranged 100 degrees across the sky, and has shown up on other surveys as several separate voids. |
In 1985, Tully determined a local dominant supercluster plane, and found the Pisces–Cetus Supercluster Complex. [22]
# | Coordinates | Distance | Diameter | Notes |
---|---|---|---|---|
(h−1 Mpc) | ||||
1 | 17.0h80° | 90 | 140 | |
2 | 21.0h−7° | 100 | 136 | |
3 | 8.6h+13° | 150 | 150 | |
4 | 21.5h+5° | 170 | 173 | |
5 | 14.3h+52° | 180 | 158 | Boötes Void |
6 | 23.0h−16° | 190 | 171 | |
7 | 12.8h+14° | 190 | 174 | |
8 | 10.0h+35° | 250 | 170 | |
9 | 2.6h−11° | 280 | 229 | |
10 | 8.7h+58° | 310 | 243 | |
11 | 16.8h+5° | 310 | 270 | |
In a 1985 study of Abell clusters, 29 voids were determined, in the sphere z<0.1 around Earth. [23]
# | Coordinates | Distance | Diameter | Notes |
---|---|---|---|---|
(h−1 Mpc) | ||||
1 | 0.0h+20° | 293 | 100 | |
2 | 0.3h0° | 276 | 100 | |
3 | 0.7h+10° | 284 | 100 | |
4 | 2.0h−13° | 275 | 150 | |
5 | 8.0h+60° | 300 | 100 | |
6 | 9.0h+18° | 220 | 100 | |
7 | 9.0h+67° | 180 | 120 | |
8 | 9.2h+26° | 137 | 140 | |
9 | 9.5h+45° | 262 | 200 | |
10 | 9.8h0° | 285 | 110 | |
11 | 9.8h+35° | 219 | 110 | |
12 | 10.8h−10° | 293 | 120 | |
13 | 12.0h+14° | 206 | 110 | |
14 | 12.3h0° | 276 | 100 | |
15 | 12.4h−12° | 272 | 150 | |
16 | 12.5h+32° | 237 | 100 | |
17 | 12.9h+64° | 105 | 110 | |
18 | 13.6h+35° | 154 | 200 | Boötes Void |
19 | 13.8h+20° | 297 | 110 | |
20 | 14.2h−4° | 265 | 210 | |
21 | 14.7h+70° | 283 | 160 | |
22 | 15.2h+42° | 286 | 140 | |
23 | 16.0h+7° | 295 | 110 | |
24 | 16.4h+41° | 291 | 130 | |
25 | 16.5h+59° | 110 | 100 | |
26 | 17.2h+58° | 237 | 100 | |
27 | 22.2h−2° | 155 | 130 | |
28 | 22.5h5° | 284 | 160 | |
29 | 23.5h−7° | 203 | 120 | |
A redshift survey of galaxies in the southern sky in 1988, out to a distance of 120 Mpc/h, revealed some voids. [24]
# | Coordinates | Distance (V) | Dimensions W × H × D (h−1 Mpc) | Constellation | Notes |
---|---|---|---|---|---|
1 | 1.5h−50° | 3000 km/s | 30 × 30 × 40 | Phoenix / Eridanus | Located just behind the galaxy concentration in Eridanus-Fornax-Dorado |
2 | 21h−25° | 5000 km/s | 30 × 30 × 30 | Capricornus / Microscopium | |
3 | 23.5h−35° | 6000 km/s | 70 × 30 × 50 | Sculptor / Grus | |
4 | 4h−40° | 9000 km/s | 50 × 100 × 50 | Horologium / Eridanus |
In 1994, a redshift survey in the southern sky identified 18 voids, 11 of which are major voids. [19]
# | Coordinates | Distance (r) | Diameter (h−1 Mpc) | Constellation | Notes |
---|---|---|---|---|---|
1 | 1h 33m−16° 45′ | 85.7 | 54.3 | Cetus | major void |
2 | 3h 34m−28° 50′ | 99.7 | 56.2 | Fornax | major void SRSS1 Void 4 |
3 | 22h 25m−14° 46′ | 107.2 | 60.8 | Aquarius | major void |
4 | 21h 43m−14° 40′ | 66.7 | 35.6 | Capricornus | major void |
5 | 23h 48m−24° 39′ | 53.0 | 34.8 | Aquarius / Sculptor | major void SRSS1 Void 3 (Sculptor Void) |
6 | 3h 56m−20° 11′ | 56.5 | 32.0 | Eridanus | major void |
7 | 3h 17m−11° 40′ | 77.2 | 25.5 | Eridanus | major void |
8 | 23h 20m−12° 32′ | 83.9 | 27.8 | Aquarius | major void |
9 | 3h 06m−13° 47′ | 114.6 | 39.0 | Eridanus | major void |
10 | 0h 26m−9° 17′ | 104.7 | 34.8 | Cetus | major void |
11 | 0h 21m−29° 43′ | 112.8 | 42.9 | Sculptor | major void |
12 | 23h 03m−32° 35′ | 74.8 | 25.0 | Piscis Austrinus / Sculptor | |
13 | 1h 23m−19° 36′ | 31.0 | 22.1 | Cetus | SRSS1 Void 1 |
14 | 21h 28m−29° 28′ | 87.2 | 21.3 | Piscis Austrinus / Microscopium | |
15 | 21h 24m−33° 17′ | 116.1 | 27.3 | Microscopium | |
16 | 21h 43m−18° 41′ | 36.5 | 20.3 | Capricornus | |
17 | 3h 42m−21° 21′ | 32.1 | 19.0 | Eridanus | |
18 | 4h 18m−8° 42′ | 85.9 | 21.1 | Eridanus |
A 1994 census lists a total of 27 supervoids within a cube of 740 Mpc a side, centered on us (z=0.1 distant sphere). [25]
# | Coordinates (B1950.0) | Distance (Mpc/h) | Diameter (Mpc/h) [Note 1] | Notes |
---|---|---|---|---|
1 | 19.0° −57.1° | 134 | 88 | |
2 | 28.2° −12.3° | 207 | 96 | |
3 | 34.8° −61.9° | 216 | 72 | |
4 | 36.6° −33.5° | 241 | 86 | |
5 | 37.8° −36.1° | 129 | 92 | |
6 | 46.0° −21.4° | 236 | 72 | |
7 | 62.0° −8.0° | 248 | 100 | |
8 | 71.2° −38.3° | 201 | 76 | |
9 | 121.7° −1.5° | 96 | 112 | Southern Local Supervoid |
10 | 130.0° +49.3° | 246 | 144 | |
11 | 140.4° +10.5° | 160 | 92 | |
12 | 146.9° +27.4° | 227 | 106 | |
13 | 153.1° −11.4° | 246 | 94 | |
14 | 159.9° +1.2° | 167 | 68 | |
15 | 161.6° −32.2° | 241 | 98 | |
16 | 167.4° +22.8° | 222 | 74 | |
17 | 186.9° −15.6° | 216 | 94 | |
18 | 196.8° +9.5° | 119 | 102 | |
19 | 204.8° +35.7° | 119 | 108 | |
20 | 214.6° +13.6° | 216 | 78 | Boötes Void (Great Void) |
21 | 216.7° +56.5° | 143 | 116 | |
22 | 219.8° +57.9° | 246 | 96 | |
23 | 220.2° +33.9° | 219 | 72 | |
24 | 256.1° −4.8° | 61 | 104 | Northern Local Supervoid |
25 | 353.0° −59.4° | 198 | 74 | |
26 | 356.6° +22.2° | 246 | 80 | |
27 | 358.9° −33.1° | 241 | 70 |
In a 1995 study of IRAS data looking for large-scale structure in the Galactic Anticenter in the Zone of Avoidance, four voids were discovered. [26]
# | Coordinates (B1950.0) | Distance (km/s) | Dimensions | Notes |
---|---|---|---|---|
V0 | 5.2h+18° | 1000 | 96°×36°×2000 km/s | |
V1 | 3.5h+18° | 3750 | 15°×36°×3500 km/s | V1 and V2 are connected, and block the Perseus–Pisces Supercluster from traversing the Zone of Avoidance. |
V2 | 3.5h+29° | 8000 | 25°×14°×2000 km/s | V1 and V2 are connected, and block the Perseus–Pisces Supercluster from traversing the Zone of Avoidance. |
V3 | 8.0h+10° | 7000 | 30°×20°×2000 km/s | This void lies in front of the CfA2 Great Wall. |
Analysis of the IRAS redshift survey in 1997 revealed 24 voids, 12 of which were termed "significant" [27]
# | Supergalactic Coordinates (r,X,Y,Z) | Diameter (h−1 Mpc) | Data | Notes |
---|---|---|---|---|
1 | (55.2,-10.4,-53.8,6.1) | 51.0 | significant void | |
2 | (49.6,-25.3,31.4,-28.9) | 43.8 | significant void | |
3 | (46.0,-24.8,26.7,28.1) | 44.5 | significant void | |
4 | (46.5,8.7,24.7,38.4) | 45.0 | significant void (Local Void) | |
5 | (32.0,-13.0,-23.9,-16.9) | 36.0 | significant void | |
6 | (51.5,17.0,-32.2,36.4) | 41.4 | significant void | |
7 | (57.1,31.2,44.9,16.5) | 43.5 | significant void | |
8 | (60.4,-25.8,-22.7,-49.7) | 39.5 | significant void | |
9 | (49.8,35.9,-25.6,-23.0) | 36.0 | significant void | |
10 | (63.3,-48.0,-40.9,6.0) | 33.6 | significant void (Sculptor Void) | |
11 | (48.6,11.8,46.6,-6.9) | 32.0 | significant void | |
12 | (49.9,-15.6,-35.7,31.3) | 31.5 | significant void | |
13 | (62.8,14.2,29.3,-53.7) | 40.3 | ||
14 | (19.0,0.7,-16.4,9.6) | 28.8 | ||
15 | (37.6,32.4,-17.0,8.6) | 30.4 | Perseus–Pisces Void |
A supercluster is a large group of smaller galaxy clusters or galaxy groups; they are among the largest known structures in the universe. The Milky Way is part of the Local Group galaxy group, which in turn is part of the Virgo Supercluster, which is part of the Laniakea Supercluster, which is part of the Pisces–Cetus Supercluster Complex. The large size and low density of superclusters means that they, unlike clusters, expand with the Hubble expansion. The number of superclusters in the observable universe is estimated to be 10 million.
The Local Supercluster is a formerly defined supercluster containing the Virgo Cluster and Local Group, which itself contains the Milky Way and Andromeda galaxies, as well as others. At least 100 galaxy groups and clusters are located within its diameter of 33 megaparsecs. The Virgo SC is one of about 10 million superclusters in the observable universe and is in the Pisces–Cetus Supercluster Complex, a galaxy filament.
The Great Attractor is a region of gravitational attraction in intergalactic space and the apparent central gravitational point of the Laniakea Supercluster of galaxies that includes the Milky Way galaxy, as well as about 100,000 other galaxies.
The observable universe is a spherical region of the universe consisting of all matter that can be observed from Earth or its space-based telescopes and exploratory probes at the present time; the electromagnetic radiation from these objects has had time to reach the Solar System and Earth since the beginning of the cosmological expansion. Assuming the universe is isotropic, the distance to the edge of the observable universe is roughly the same in every direction. That is, the observable universe is a spherical region centered on the observer. Every location in the universe has its own observable universe, which may or may not overlap with the one centered on Earth.
The Hydra–Centaurus Supercluster, or the Hydra and Centaurus Superclusters, was a previously defined supercluster in two parts, which prior to the identification of Laniakea Supercluster in 2014 is the closest neighbour of the former Virgo Supercluster. Its center is located about 39 Mpc (127 Mly) away, with it extending to a maximum distance of around 69 Mpc (225 Mly).
The Las Campanas Redshift Survey is considered the first attempt to map a large area of the universe out to a redshift of z = 0.2. It was begun in 1991 using the Las Campanas telescope in Chile to catalog 26418 separate galaxies. It is considered one of the first surveys to document the so-called "end of greatness" where the Cosmological Principle of isotropy could be seen. Superclusters and voids are prominent features in the survey.
The Sloan Great Wall (SGW) is a cosmic structure formed by a giant wall of galaxies. Its discovery was announced from Princeton University on October 20, 2003, by J. Richard Gott III, Mario Jurić, and their colleagues, based on data from the Sloan Digital Sky Survey.
The Pavo–Indus Supercluster is a neighboring supercluster located about 60–70 Mpc (196–228 Mly) away in the constellations of Pavo, Indus, and Telescopium. The supercluster contains three main clusters, Abell 3656, Abell 3698, and Abell 3742.
In cosmology, galaxy filaments are the largest known structures in the universe, consisting of walls of galactic superclusters. These massive, thread-like formations can commonly reach 50/h to 80/h megaparsecs —with the largest found to date being the Hercules-Corona Borealis Great Wall at around 3 gigaparsecs (9.8 Gly) in length—and form the boundaries between voids. Due to the accelerating expansion of the universe, the individual clusters of gravitationally bound galaxies that make up galaxy filaments are moving away from each other at an accelerated rate; in the far future they will dissolve.
The Hercules Superclusters refers to a set of two nearby superclusters of galaxies.
The Huge Large Quasar Group, is a possible structure or pseudo-structure of 73 quasars, referred to as a large quasar group, that measures about 4 billion light-years across. At its discovery, it was identified as the largest and the most massive known structure in the observable universe, though it has been superseded by the Hercules–Corona Borealis Great Wall at 10 billion light-years. There are also issues about its structure.
Cosmic voids are vast spaces between filaments, which contain very few or no galaxies. In spite of their size, most galaxies are not located in voids. This is because most galaxies are gravitationally bound together, creating huge cosmic structures known as galaxy filaments. The cosmological evolution of the void regions differs drastically from the evolution of the universe as a whole: there is a long stage when the curvature term dominates, which prevents the formation of galaxy clusters and massive galaxies. Hence, although even the emptiest regions of voids contain more than ~15% of the average matter density of the universe, the voids look almost empty to an observer.
Abell 2162 is a galaxy cluster in the Abell catalogue located in the constellation Corona Borealis. It is a member of the Hercules Superclusters, the redshifts of the member galaxies of which lie between 0.0304 and 0.0414. The cluster hosts a massive Type-cD galaxy called NGC 6086.
The Taurus Void is a vast, near-empty region of space situated between the Perseus–Pisces Supercluster and the Virgo Supercluster. The Taurus void is unique because of its relatively close proximity to Earth, and because it helps to define the edge of latter's home supercluster, the Virgo Supercluster. Despite its close proximity to Earth, the Taurus Void is not well-studied because it is partially obscured by the Milky Way when viewed from Earth. In contrast to its ambiguous boundary in the section of sky obscured by the Milky Way, the Taurus Void has a very well-defined boundary with the Perseus–Pisces supercluster.
The Southern Supercluster is a nearby supercluster located around 19.5 Mpc (63.6 Mly) in the constellations of Cetus, Fornax, Eridanus, Horologium, and Dorado. It was first identified in 1953 by Gérard de Vaucouleurs.
The NGC 4065 Group is a group of galaxies located about 330 Mly (100 Mpc) in the constellation Coma Berenices. The group's brightest member is NGC 4065 and located in the Coma Supercluster.
Draco Supercluster (SCL 114) is a galaxy supercluster in the constellation Draco. It is located at a distance of 300 Mpc h−1 on a side of a void of diameter of about 130 Mpc h−1. The near side of the void is bordered by the Ursa Major supercluster. The estimated size of the supercluster reaches 410 million light years and a mass of 1017 M☉, making it one of the largest and most massive superclusters known in the observable universe.