Talk:Void (astronomy)

message: voids are approx size of superclusters, supervoids are approx size of walls... or so it seems? 70.51.11.219 (talk) 08:06, 2 August 2008 (UTC)
thread_title: size

message: A 1994 census lists a total of 27 supervoids with a distance of up to 740 Mpc.
# 	Name                     	Distance (h-1Mpc)To the center of the void	Diameter (h-1Mpc)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.
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 <---- that one has not been verified by any source other than a single webpage.
* The Eridanus Supervoid (Great Void), reported on 24 August 2007 by the NRAO from Very Large Array Sky Survey data, is much larger than these, being about 300 h-1Mpc in diameter and 1800–3000 h-1 Mpc distant. It also corresponds to a cold spot in the cosmic microwave background. "Astronomers Find Enormous Hole in the Universe". National Radio Astronomy Observatory Press release, retrieved 24 August 2007.
This was the original list on the page. 
76.66.198.46 (talk) 12:28, 15 November 2008 (UTC)
thread_title: old list

message: Wonder if the voids have a black hole at their center. If that were true someone else would have thought of it and tried to check for any form of evidence.  —Preceding unsigned comment added by 198.53.87.153 (talk) 00:19, 10 September 2009 (UTC)
replies: text: I don't think so, matter appears to leave voids for concentrations of matter. If there were black holes, they would attract matter... ofcourse this is assuming extremely supermassive blackholes are what you're referring to. There are black holes in the voids because there are galaxies in the voids. Galaxies have stars, which produce stellar mass black holes. The galaxies themselves have supermassive central black holes. 76.66.196.139 (talk) 01:29, 21 September 2009 (UTC)
replies: text:  Could it be possible that one or more blackholes sucked in pretty much everything they could, and what is left is the stuff at the borders of the void that due to the expansion of space are moving away faster than the blackholes can pull at that distance? --TiagoTiago (talk) 21:17, 7 November 2011 (UTC)
replies: text: If there was a supercluster mass blackhole in a void it would bend light and it would have a large gravitational lensing effect, which is not observed. Known dark matter is plotted in this diagram :File:COSMOS 3D dark matter map.jpg but I cannot see how it aligns with voids or clusters. Graeme Bartlett (talk) 02:35, 8 November 2011 (UTC)

text:  You should propose realistic scenarios. The only known way to make black holes is to stuff a lot of conventional matter together as in a galaxy. Such collapse is inefficient and will throw out a lot of stars and gas. That'd be easily visible. I think you have a fundamental misunderstanding of what gravity is. Gravity is a force field, not suction, and a black hole is not a giant vacuum cleaner. That means that a star falling in a gravity field will convert its gravitational potential energy into kinetic energy, speeding up. So, if it doesn't exactly hit the black hole (which is unlikely as it would take incredible aim), it will just speed past the black hole like a comet, then head back up the gravity well, losing kinetic energy as it slows down. So, no energy is actually lost anywhere, just converted from potential to kinetic energy and back. The only known way to lose the kinetic energy is to hit something on the way. That will release heat, in practice in the form of an accretion disc of a quasar. They are the brightest objects in the universe. --vuo (talk) 21:36, 29 August 2014 (UTC)
thread_title:  hmm 

message: Vuo added this: "Voids were formed by baryon acoustic oscillations" with no citation.  Surely this is only a hypothesis and not an accepted fact. How should this statement be qualified? Graeme Bartlett (talk) 08:21, 25 May 2011 (UTC)
thread_title: Baryon acoustic oscillations

message: This article only talks about what a void physically is and not about the history of a void. The history section could talk about how the idea of a void was first introduced by the atomists, turned down by Aristotle and then later accepted by Christaan Huygens and Evangelista Torricelli. I think adding this section would give the article more substance and make it more informational. What do you think? Chargerfan12 (talk) 00:50, 24 May 2013 (UTC)
thread_title: History

message: According to recent reports the local supervoid is much larger than previously thought and may be the largest known object in the universe."Cold Spot suggests largest structure in Universe: A supervoid 1.3 billion light years across"  Royal Astronomical Society (RAS) April 20, 2015 551 Mpc if my math is correct. Maybe this information should be added to this page or the list of voids? 
Grizzlebizzle (talk) 09:32, 21 April 2015 (UTC)
thread_title: Local Supervoid Update

message: *1617 print depicts nothingness prior to the universe
*Robert Fludd and His Images of The Divine
I thought that images from this work might work in this article. I do not have time to look into this just now, so I thought that I would make a note here.  Blue Rasberry (talk) 19:58, 10 October 2017 (UTC)
thread_title:  Illustration of void 

message: void: beyond the event horizon of this Universe and black holes where there is no space and no time. 2601:580:102:4DA8:D8CB:EB0A:EADC:FA44 (talk) 15:34, 11 July 2019 (UTC)
replies: text: I'm not quite sure what you're asking for here. Do you want this article to include that definition? Where did you even get that definition from? Captain Eek Edits Ho Cap'n!⚓ 20:21, 11 July 2019 (UTC)
thread_title:  Void (definion 2 - Astronomy): beyond the event horizon of this Universe and black holes where there is no space and no time  

message: The illustration of matter density in the article resembles detergent foam. With a foam all we see is the detergent but the main component (without which it could not exist) is the gas within each bubble or void. Is it possible that the voids are made of some form of dark matter exerting a force equivalent to negative gravity? Or, perhaps, they could be the home of a dark energy.
If we have some field or dark matter exerting a repulsive force on ordinary matter would we need massive dark matter at all?  — Preceding unsigned comment added by Stan staveley (talk • contribs) 17:18, 26 December 2020 (UTC)
thread_title:  Another way of looking at voids (and dark matter) 

message: calling things first, second, third class SHOULD technically be a descriptor of "well this is the first class of algorithms this is the second class, and so forth", but general english speech patterns have it that "first class " means BETTER than "second class" and "third class"
im pretty sure this article isn't trying to make a statement that any of those algorithms are somehow superior to the other 2600:6C47:A03F:C443:E534:BFCC:9963:7EBA (talk) 15:16, 22 August 2023 (UTC)
thread_title:  "first class" "second class" "third class"