The next Skeptics' Circle is coming up fairly quick. steppen wolf asked me to tell you to please get your submissions in to the Skeptical Alchemist before July 4th.
Looking forward to some good Skeptical blogging.
Saturday, June 30, 2007
Friday, June 29, 2007
This weeks Friday beautiful science comes from Eye of Science:
Scales from the skin of a shark. These sharply pointed placoid scales are also known as dermal teeth or denticles. They give the shark's skin the feel of sandpaper. The tip of each scale is made of dentine overlayed with dental enamel. The lower part of each scale, which anchors it into the skin, is made of bone. The scales disrupt turbulence over the skin, considerably reducing the drag on the shark as it swims. This design has been investigated by engineers for use on the surfaces of aircraft and boats. Coloured scanning electron micrograph, Magnification: x70.Eye of Science is a:
two-person team of photographer and biologist,
our aim is to combine scientific exactness with aesthetic
appearances, and thereby help to bridge the gap
between the world of science and the world of art.
Thursday, June 28, 2007
ERV appears to have tagged me. Thanks, ERV. I've never played one of these games before, but here goes...
Here are the rules:
- We have to post these rules before we give you the facts.
- Players start with eight random facts/habits about themselves.
- People who are tagged need to write their own blog about their eight things and post these rules.
- At the end of your blog, you need to choose eight people to get tagged and list their names.
- Don’t forget to leave them a comment telling them they’re tagged, and to read your blog.
I'm going to bast**rdize this little meme. Partly because I'm a little bit private, and partly because I'd like to write about the thing that is currently stressing me the most. I'm currently applying for my green card (I'm an alien). I thought I would reveal the 8 most ridiculous questions on the green card application (not necessarily in any particular order). But that's still following the rules, right? These questions are about me, and I will answer all of them. From the form I-485:
1. Do you intend to engage in the United States in espionage?Hmmm... you supposed a spy entering the U.S. answers this one honestly? But for me? No. I promise I won't engage in espionage.
2. Do you intend to engage in the United States in any activity a purpose of which is opposition to, or the control or overthrow of, the government of the United States, by force, violence or other unlawful means?No.
3. Have you ever engaged in genocide, or otherwise ordered, incited, assisted or otherwise participated in the killing of any person because of race, religion, nationality, ethnic origin or political opinion?No. I have not.
4. Do you plan to practice polygamy in the United States?Does hoping count? I think my wife would kill me if I took a second wife, but a guy's gotta dream, doesn't he?
5. Have you received public assistance in the United States from any source, including the United States government or any state,county, city or municipality (other than emergency medical treatment), or are you likely to receive public assistance in the future?I had a research fellowship from the American government once. Does that count?
6. Have you ever been a member of, or in any way affiliated with, the Communist Party or any other totalitarian party?No. I have not.
7. Have you ever engaged in any unlawful commercialized vice, including, but not limited to, illegal gambling?Until single-malt scotch becomes illegal, I will have to say no.
And from the medical exam:
8. (Do you have) tuberculosis? syphilis? insanity? mental defect? mental retardation? previous occurrence of one or more attacks of insanity? psychopathic personality? gonorrhea? sexual deviation?They seem to be worried that I might be insane. Hmmm. Doc says I passed that one.
I'm also going to dead-end this meme, because most of the blogs I read regularly have already been tagged, and because I'm no fun.
A central feature to believing that global warming isn't happening is a conspiracy to hide the truth. You cannot hold the belief that global warming isn't happening without also believing that the scientists who study it are either incompetent or conspiring to defraud the public or a combination of both. I think many people who hold this belief aren't aware of the vast number of people involved. This isn't 12 pointy-headed scientists that have come up with this idea. Anthropogenic global warming is supported by data gathered by a vast array of people.
So how many people are involved in this Grand Conspiracy to defraud Americans?
Let's count them:
The scientists of the International Panel for Climate Change:
2500+ scientific expert reviewers
850+ Contributing authors
450+ lead authors
Panels of the National Academies of Science of the U.S.
250+ of America's most talented and honored scientists
American Meteorological Society:
11,000 professionals, professors, students, and weather enthusiasts
American Geophysical Union:
45,000 scientists from 140 countries
This is just the scientists. From the most honored members of the National Academies, down to graduate students who are members of the American Meteorological Society. Roughly 60,000+ scientists would need to be involved. 60,000+ scientists keeping a secret that is so massive that they are able to defraud the world.
Now keep in mind, to hold the position that global warming isn't occurring and isn't caused by manmade carbon emissions you must also hold that 60,000+ scientists are so conspiring to defraud Americans. (The most common accusation I have read is that they are merely in it for the grant dollars).
So either 60,000+ scientists are defrauding the world and Michael Crichton has managed to figure it out on his own, or 60,000+ scientists are actually doing their jobs, and have shown that global warming is happening and is caused my manmade carbon emissions.
Wednesday, June 27, 2007
The number of commenters here at Conspiracy Factory seems to have increased. Previously, my level of traffic was low enough that generally I could tell the difference between anonymous commenter #1 and anonymous commenter #2. Now, I get a little schizophrenic reading the replies to each other where I can't tell who is who.
That said, I've turned off anonymous commenting, and suspect I won't be turning it back on in the near future.
So go ahead, go get yourself an account. Choose a pseudonym. You still get to be anonymous. But this way, I can tell you apart from other commenters.
Edit: Nov 2007. I'm allowing anonymous commenting again, to increase the number of commenters. However, given some product spamming that I've been getting, I'm now moderating comments. If you're not selling garbage, or you're not being obnoxiously rude, your comments will get through.
"Three can keep a secret if two are dead."
How many people can really keep a secret? I mean really keep a secret. Not utter it out loud, not write about it, not bitch about it over beers, but really and truly keep it a total and utter secret, safe from the world? I think I can keep a secret. My wife claims that I keep more secrets than almost anyone she knows.
Several years ago I was shopping for a Christmas gift for my then-girlfriend. I had flown in from out of town to visit with her and her family, so I was totally without a vehicle or any form of transportation.
She had recently gotten into photography in a semi-serious way, and I wanted to buy her an SLR camera for Christmas, but I didn't have the means to get to a camera store. So I arranged with her that we would go shopping with her parents' car, and I would blindfold her a few blocks from the store, and she agreed she would keep her eyes closed (she liked surprises far more than I did) while I went shopping. It was truly a convoluted plan, and in retrospect it was doomed to failure from the start. So that morning, we were ready to head out, and I was making a verbal list of all the things she and I were going to do that day. "Go to the movies, go get a present for my brother, go for lunch with your friends, go buy your camera...." Doh. I had blurted it out, just like that. I realized immediately what I had done, and I looked at my girlfriend in horror. She just smiled and said, "I thought that's what you were getting me."
Secrets have a way of coming out, even if you've never shared them. But what about when more than one person knows that secret? How hard is it to keep? I spent some time last night looking through PsychInfo for research on the difficulty (or ease) of keeping a secret. I confess I was unsuccessful (that said, I have a hard time imagining an ethical experiment that could test how well the average person keeps a secret). Most of the literature focuses on how damaging to one's psyche keeping a family secret can be.
So let's merely think about this, and I'll pose a few more questions. Could you keep a secret about yourself? What about if that secret is one that actually affects other people? For example, what if you harbor a secret about someone who is poisoning their wife? Could you keep that a secret? Do you know ten people you could share this with that would keep a poisoning secret? What about 10,000?
At the heart of most denialism is the need for there to be a conspiracy. For example, if mercury does in fact cause autism, tens of thousands of scientists would have to know this and be keeping it secret. Robert F. Kennedy Jr. claims that the CDC and the pharmaceutical industry have conspired to keep the dangers of mercury a secret. They would have to be complicit in a scheme to poison millions of children.
So how is it exactly that one gathers together a football stadium worth of people, reveal to them a secret that is so grotesque as that of poisoning millions of children, and then demand that they all keep it a secret?
Tuesday, June 26, 2007
Monday, June 25, 2007
The Hoofnagles gave us an entertaining view of a troofer a few weeks ago. This gentleman tried to simulate the fall of the twin towers on 9/11 using office supplies. It's clearly a mess.
Researchers at Purdue University recently released a slightly higher quality simulation of the crash:
The simulation could be used to better understand which elements in the building's structural core were affected, how they responded to the initial shock of the aircraft collision, and how the tower later collapsed from the ensuing fire fed by an estimated 10,000 gallons of jet fuel, said Mete Sozen, the Kettelhut Distinguished Professor of Structural Engineering in Purdue's School of Civil Engineering.Their findings? The towers lost 25% of their core support beams:
It took about 80 hours using a high-performance computer containing 16 processors to produce the first simulation, which depicts how the plane tore through several stories of the structure within a half-second, said Christoph M. Hoffmann, a professor of computer science and co-director of the Computing Research Institute at Purdue.
The researchers are analyzing how many columns were destroyed initially in the building's core, a spine of 47 heavy steel I-beams extending through the center of the structure, Sozen said.It remains to be seen if this has much effect on the troofer movement. (Don't hold your breath).
"Current findings from the simulation have identified the destruction of 11 columns on the 94th floor, 10 columns on the 95th floor and nine columns on the 96th floor," he said. "This is a major insight. When you lose close to 25 percent of your columns at a given level, the building is significantly weakened and vulnerable to collapse."
Apparently the researchers at Purdue are currently working on modeling the fall of the towers:
In the coming months, we will explore how the structure reacted to the extreme heat from the blaze that led to the building's collapse, and we will refine the visual presentations of the simulation.The video of the simulation is below. It's fascinating to watch, even if it is disturbing.
Friday, June 22, 2007
I've been following the Autism Omnibus trial in Washington D.C. (if you have time, read some of the transcripts - they're fascinating - or for an excellent summary, head over to Autism Diva) over the last 2 weeks, and it got something stirring in my head. How many people would it take to pull off the grand conspiracy that the Mercury Militia and Robert F. Kennedy Jr. are supposing?
First, an overview:
Over ten years ago now, Dr. Geier, an M.D. based out of Maryland, proposed the hypothesis that the preservative in vaccines caused autism. His hypothesis was based on two ideas. One, that many parents first noticed autism symptoms in their children shortly after their second year vaccinations. And two, that the preservative in vaccines (thimerosal) is a compound that contains mercury, and other mercury compounds are known neurotoxins. At the time, it was a shaky, but testable hypothesis.
Since then, numerous epidemiological and toxicological studies (summarized by the National Academies here) have failed to find any link between the preservative thimerosal and autism. In fact, thimerosal has been removed from most vaccines in Canada and the United Kingdom (and more recently in the U.S.) and none of those countries have seen a decrease in the level of autism, suggesting very strongly, that thimerosal does not cause autism.
Several groups and individuals (most notably Robert Kennedy Jr.) have suggested that a grand conspiracy exists that is duping the American public to prevent the truth being known (that is, that thimerosal causes autism).
So, for this to be true, who would have to be in on this grand conspiracy to dupe the American public?
-some employees of the FDA (at least a few hundred people)
-some employees at the CDC (at least a few hundred people)
-15 distinguished members of the National Academy of Sciences (NAS)
-members of the labs of those 15 distinguished members of the NAS (at least 150 people total)
-the lawyers that work at the Health and Human Services Department (<100)
-the employees at the world's vaccine companies - an incomplete list being here (with employees in parentheses):
Emergent Biosolutions (?)
Eli Lilly (44,000)
- the vast majority of academic autism researchers (~1000)*
- the vast majority of academic vaccine researchers (~10000)*
Giving a rough total of 300,000 people in on this conspiracy to poison the American people. Did I miss anyone?
* these numbers are a bit hand waving, as I get them by typing the word vaccine or autism into pubmed, and dividing the number of publications by 10
Today's Friday Beautiful Science is a depiction of the tree of life, done as a sphere. Previously, I've discussed the limitations of depicting phylogeny on a standard tree, and suggested that doing it as a circle or a sphere would be more useful. Turns out I'm not the only one who thinks that. This is one particular 3-D visualization that I've taken from Tim Hughes at the University of Bergen (he has several others at his site). Yet other 2-dimensional visualizations can bee seen here.
Thursday, June 21, 2007
Wednesday, June 20, 2007
Given the time that has elapsed since the first mention of Colony Collapse Disorder in the popular press, it's nice to finally see some scientific publications trying to address this issue.
Last week, PLoS Biology, the free online scientific journal, published an Unsolved Mystery. Benjamin Oldroyd, a bee entomologist at the University of Sydney, writes about Colony Collapse Disorder:
On February 22, 2007, many Americans woke up to media reports that something was awry with their honey bees. A significant proportion of American beekeepers were complaining of unusually high rates of colony loss as their bees broke from their overwintering clusters. Loss of some colonies (say 10%) in early spring is normal and occurs every year. In 2007, however, losses were particularly heavy and widespread—beekeepers in 22 states (including Hawaii) reported the problem. Some beekeepers lost nearly all of their colonies. And the problem is not just in the United States. Many European beekeepers complain of the same problem. Moreover, beekeepers and researchers do not understand the specific causes of the losses.He puts it in historical perspective:
Some winter losses are normal, and because the proportion of colonies dying varies enormously from year to year, it is difficult to say when a crisis is occurring and when losses are part of the normal continuum. What is clear is that about one year in ten, apiarists suffer unusually heavy colony losses. This has been going on for a long time. In Ireland, there was a “great mortality of bees” in 950, and again in 992 and 1443 . One of the most famous events was in the spring of 1906, when most beekeepers on the Isle of Wight (United Kingdom) lost all of their colonies . American beekeepers also suffer heavy losses periodically. In 1903, in the Cache valley of Utah, 2000 colonies were lost to a mysterious “disappearing disease” following a “hard winter and cold spring” . More recently, there was an incident in 1995 in which Pennsylvania beekeepers lost 53% of colonies .So this has been going on for some time.
Often terms such as “disappearing disease” or “spring dwindling” are used to describe the syndrome in which large numbers of colonies die in spring due to a lack of adult bees [7,8,9]. However in 2007, some beekeepers experienced 80–100% losses. This is certainly the extreme end of a continuum, so perhaps there is indeed some new factor in play.
He covers several possible causes, but zeroes in on two:
We have seen that a large number of factors can produce CCD-like symptoms. We have also seen that CCD is not new: CCD-like symptoms have been known to beekeepers for more than a hundred years but are sufficiently infrequent that when symptoms are severe, beekeepers become concerned that there is something new afflicting their bees.And he provides tests for his hypothesis. Brilliant!
Clearly CCD is a multifactorial syndrome. Some researchers have suggested that the bees are suffering immunosuppression. Certainly, expression of immune genes in insects is costly [56–58], and if bees are stressed by other causes, they may be less able to mount an effective immune response to pathogens [see Box 1]. This idea is now eminently testable, because the honey bee genome has been sequenced , and this provides researchers with new tools to tackle problems like CCD. A microarray of honey bee immune genes and genes from their pathogens is available , and this could be used to determine if the known immune genes are underexpressed in colonies suffering from CCD.
I suggest that another possible cause of CCD might simply be inadequate incubation of the brood. Thus any factor—infections, chronic exposure to insecticides, inadequate nutrition, migration in adult population, and inadequate regulation of brood temperature might cause CCD-like symptoms.
My hypothesis could be easily tested by removing brood from several colonies and incubating some of it at optimal temperature and some at suboptimal temperature. The brood would then be used to constitute new colonies in which some colonies comprise workers raised at low temperature and some comprise workers raised at optimal temperature. I predict that the colonies comprising workers reared at suboptimal temperature will show signs of CCD. Moreover, I would not be surprised if they showed higher levels of stress-related viral infections. These effects could act synergistically—more virus leads to shorter-lived, less efficient workers, that in turn leads to suboptimal temperature regulation, and more short-lived bees.
Tuesday, June 19, 2007
ERV wrote yesterday about a cool, new genetically-modified food that has the potential to act as a vaccine against cholera. The basic idea is that they are expressing a gene from cholera in rice. When you eat the rice, you are exposed to the fragment of a protein from cholera and will make antibodies to it. That way when you are exposed to cholera in the future, you will be immune to it. What are the advantages of this approach? From ERV:
So really this rice is going to be ground up and put into pill form, which is fantastic on so many levels!I thought I would write about another super cool approach to vaccines of the 21st century, and this one is a little closer to home as my wife and I both work on things that are indirectly related to this. (Though I confess, I'm a little worried that this post will attract the anti-vaccination mob along with the anti-genetic-engineering crowd).
1. Dont need a needle. Ive said over and over and OVER (are you listening, HIV-Circumcision 'researchers'??) its really damn hard to make sure your needles/equipment is appropriately sterilized in the third world. I dont care how many seminars youve had on how to sterilize needles. It doesnt always get done. Plus, I dont think youll hear any kids complaining about a lack of needles ;)
2. Can be kept at room temperature. No refrigeration. Aint gonna always have that in the third world either. Sure you might have a fridge, but it might not have power. And they tested batches that were left at room temp for 1.5 years-- Still worked. AWESOME!
3. Introducing the antigen through the intestinal mucosa. These folks found that introducing the cholera antigen orally works great because cholera normally infects through your digestive tract! Convinces lots of sentinel immune cells to hang out in your intestine and wait for another cholera bug to float by!
Live-vector vaccines are what a lot of folks are hoping will be the vaccines of the future. How do they work? Over the last 30 years, we've learned an awful lot about how several different bacterial pathogens work. Pathogens like Salmonella and Listeria actually enter your cells and express their genes inside you (these are not viruses, mind you, but bacteria that go intracellular). We also know an awful lot about how to stop pathogenesis at certain steps. There are all kinds of mutants that are able to go intracellular, but are blocked at later stages of pathogenesis, so are unable to spread, or unable to express certain toxins, or otherwise unable to complete the disease process.
How does this help us build vaccines? These mutants that are blocked at later stages of pathogenesis actually elicit an immune response from the host. That is, when your body sees foreign bacteria in their cells, you are able to mount a potent immune response to it, so the second time you see Salmonella or Listeria, you are able to fight it off (though given that Salmonella has so many different varieties, it is quite difficult to vaccinate against all of them). It also allows you to mount both an antibody response and a cell-mediated response (these are two different immune responses that I will write about later). The long and the short of it is that most vaccines only elicit an antibody response, which doesn't protect well against pathogens that climb inside your cells to evade the antibodies.
Well, these days it is rather trivial to genetically engineer Salmonella. And Listeria is also able to be genetically engineered. So it's easy to put genes from another pathogen into them. (And before you cry, "What?! You're building a superbug?!! - it takes hundreds of genes working in concert to create a pathogen. One or two genes does not a pathogen make). One example of a live vector vaccine is here. Folks at the Center for Vaccine Development put part of the tetanus toxin into Salmonella. They then gave the Salmonella to mice, and found that the mice made antibodies to tetanus that have been previously shown to be able to protect them from infection.
So, big fat hairy deal. They've built a vaccine for an infection that there is already a potent vaccine available. Well, this is a potent demonstration that this technology is viable. There are a bunch of labs working to build vaccines against disease in a similar manner (including for diseases that don't currently have available vaccines).
What are the advantages of this approach? It's similar to the rice vaccine above:
1. You can get both cell-mediated and antibody immune responses, whereas most subunit vaccines that are available only give an antibody response. In non-science language: your immune system responds in a way that's more likely to prevent disease.
2. No needles! (You can just drink this).
3. Easier shipment and administering of the vaccine. And shipping to remote locations (think parts of Africa & Asia) is much simpler. That, and you don't need to have anyone who is highly trained giving the vaccine. Merely an eyedropper and a bottle to drop it into a glass of water will do.
4. Cheap. Growing Salmonella is easy. And building genetically modified Salmonella is infinitely easier than genetically modified plants or animals.
5. Generalizable. It is easy to imagine building multiple different vaccines in this manner, and then administering them simultaneously (either as a single organism, or a cocktail of several different bugs).
But what is the downside? The upfront costs will be high. New vaccines are expensive as the manpower to make them is highly skilled, and the number of tests that they have to undergo to demonstrate safety is high.
The other major downside is the PR side. The public at large is so woefully uneducated about basic science issues, and even conventional vaccines have been controversial in the public arena. I can only imagine the anti-vaccination folks now:
Genetically modified pathogens! *gasp* You're playing God!Yep, every time you save a kid from a disease you're playing God. Some people think that's okay. I think that the time is right to start telling people about these vaccines so that when they do start to become commercially available that there isn't a visceral, knee-jerk reaction against them. When I tell people about what I do, they say, "You genetically engineer bacteria? Why would you want to do that?". If they're calm enough to sit down for a few minutes and talk to me about it, they often ultimately agree that it is a good idea.
Monday, June 18, 2007
I've been a little quiet lately. Here's something that got me interested in posting: What are the sickest searches that people have done to find your blog? Let me clarify. These are searches that people did in Google that gave them a link for me (and on the ones I checked, I showed up in the first or second page). I've listed them below, including links so that you can see the context that those words came up in my blog (that said, a couple of them came up on keyword search pages combining multiple posts).
Well, I confess there aren't that many sick searches being done for my blog (should I be disappointed?). But the few disturbing ones that I did have were extremely disturbing:
"want to hurt your baby"
broken baby bones conspiracy
homeopathic remedy for autism son that likes mother's butt
Happily there are also some funny ones. Try:
can i own a howitzer??
alcohol consumption before getting the hpv shot
moon colony conspiracy
global infertility conspiracy (actually, add conspiracy to anything, I get a lot of hits that way)
ld50 of water
factories allow bugs in food
what does you worries about genetically food <-- this one just makes me laugh because of the grammar
hat tip: Pharyngula
Update: There's a funny post written to Google searchers here. Check it out.
Friday, June 15, 2007
Today's Friday beautiful science focuses on the work of Felice Frankel. She's a photographer at MIT who works with scientists to take cool photos of their work. The photo above was taken of a ferromagnetic fluid on a glass slide with seven magnets underneath. There are several other of her photos displayed in a recent New York Times profile of her. She has one book of photos (On the Surface of Things) that's out of print, and another (Envisioning Science: The Design and Craft of the Science Image) that is intended for photographers.
If anyone can point me towards a source for her prints, I would appreciate it.
Thursday, June 7, 2007
Today's Friday beautiful science was posted recently on Pharyngula. I've already watched it about 15 times, it's very cool. This video shows a small cephalopod un-camouflaging itself and fleeing from a diver. Very cool, it manages to change the color of its skin in just over 2 seconds.
PZ Myers has an interesting discussion about the ability of cephalopods to camouflage themselves so quickly. Read it here.
Here's another video where you can get a really good idea of how quickly they can change color. In this case, it appears the cephalopod is dead, and yet it continues to change color.
Wednesday, June 6, 2007
It came to my attention today that whether or not the brain is important to the human organism is still an open question. No, really.
Denyse O'Leary, a frequent intelligent design advocate at Uncommon Descent writes in her post entitled Brain: Do you really need a brain?:
Recent research has cast doubt on just how neurons transmit information in the brain, and some wonder just what role the brain as a whole plays in thinking.Beg pardon? What role the brain plays in thinking? I thought this problem had been solved quite some time ago... But no, she presents this anecdote from Richard Milton:
In 1970, a New Yorker died at the age of 35. He had left school with no academic achievements, but had worked at manual jobs such as building janitor, and was a popular figure in his neighbourhood. Tenants of the building where he worked described him as passing the days performing his routine chores, such as tending the boiler, and reading the tabloid newspapers. When an autopsy was performed to determine the cause of his premature death he, too, was found to have practically no brain at all.What, no data? Watch, I can do that too. I knew a guy in college. He doesn't have a liver. Or a heart. Nice guy. I wonder what role the heart plays in pumping blood... Apparently not an important one. (hint: I'm lying).
But wait, Mr. Milton has more to contribute to this important topic:
what on earth is the brain for? And where is the seat of human intelligence? Where is the mind?Watch for it. Next you'll be hearing demands for medical schools to teach the controversy.
Update: Thanks to Paul for pointing me towards the original proprietor of this anecdote: John Lorber. An brief news report was published about him in Science over 20 years ago. Nonetheless, in the intervening period, apparently he has never published proof of his brainless wonder.
Tuesday, June 5, 2007
... that I could some day publish a paper that has as cool a title as this:
Threatening a rubber hand that you feel is yours elicits a cortical anxiety response
Monday, June 4, 2007
Friday, June 1, 2007
Although astronomers cannot see dark matter, they can infer its existence in galaxy clusters by observing how its gravity bends the light of more distant background galaxies, a powerful effect called gravitational lensing. The blue streaks near the center of another Hubble image of the cluster are the distorted shapes of more distant galaxies, whose light was bent and magnified by the powerful gravity of Cl 0024+17.This photo is a map of the dark matter that they found, superimposed on a photograph taken by the Hubble space telescope. What is dark matter?
[Dark matter] is an invisible substance composed of atoms that are far different from those that make up the universe’s normal matter, such as stars and galaxies.
In fact, if you drove into a wall made of dark matter, you wouldn’t crack a headlight or inflate an airbag. You wouldn’t even know it happened. But what happens to dark matter during a collision?
Astronomers using NASA’s Hubble Space Telescope got a first-hand view of how dark matter behaves during a titanic collision between two galaxy clusters. The wreck created a ripple of dark matter, which is somewhat similar to a ripple formed in a pond when a rock hits the water.
The ring's discovery is among the strongest evidence yet that dark matter exists. Astronomers have long suspected the existence of the invisible substance as the source of additional gravity that holds together galaxy clusters. Such clusters would fly apart if they relied only on the gravity from their visible stars. Although astronomers don't know what dark matter is made of, they hypothesize that it is a type of elementary particle that pervades the universe.