Dark matter dark matter© MinutePhysics (A Britannica Publishing Partner)a component of the universe whose presence is discerned from its gravitational attraction rather than its luminosity. Dark matter makes up 26.5 percent of the -energy composition of the ; the rest is dark energy (73 percent) and “ordinary” visible matter (0.5 percent).
Originally known as the “missing mass, ” dark matter’s existence was first inferred by Swiss American astronomer Fritz Zwicky, who in 1933 discovered that the mass of all the stars in the Coma cluster of galaxies provided only about 1 percent of the mass needed to keep the galaxies from escaping the cluster’s gravitational pull. The reality of this missing mass remained in question for decades, until the 1970s when American astronomers Vera Rubin and W. Kent Ford confirmed its existence by the observation of a similar phenomenon: the mass of the stars visible within a typical galaxy is only about 10 percent of that required to keep those stars orbiting the galaxy’s centre. In general, the speed with which stars orbit the centre of their galaxy is independent of their separation from the centre; indeed, orbital velocity is either constant or increases slightly with distance rather than dropping off as expected. To account for this, the mass of the galaxy within the of the stars must increase linearly with the distance of the stars from the galaxy’s centre. However, no light is seen from this inner mass—hence the name “dark matter.”
gravitational lens: caused by a galactic clusterPhoto AURA/STScI/NASA/JPL (NASA photo # STScI-PRC96-10)Since the confirmation of dark matter’s existence, a preponderance of dark matter in galaxies and clusters of galaxies has been discerned through the phenomenon of gravitational lensing—matter acting as a lens by bending space and distorting the passage of background light. The presence of this missing matter in the centres of galaxies and clusters of galaxies has also been inferred from the motion and heat of gas that gives rise to observed X-rays. For example, the Chandra X-ray Observatory has observed in the Bullet cluster, which consists of two merging galaxy clusters, that the hot gas (ordinary visible matter) is slowed by the drag effect of one cluster passing through the other. The mass of the clusters, however, is not affected, indicating that most of the mass consists of dark matter.
matter-energy content of the universeEncyclopædia Britannica, Inc.Twenty-seven percent of the universe’s matter-energy composition is matter. Only 0.5 percent is in the mass of stars and 0.03 percent of that matter is in the form of elements heavier than hydrogen. The rest is dark matter. Two varieties of dark matter have been found to exist. The first variety is about 4.5 percent of the and is made of the familiar baryons (i.e., protons, neutrons, and atomic nuclei), which also make up the luminous stars and galaxies. Most of this baryonic dark matter is expected to exist in the form of gas in and between the galaxies. This baryonic, or ordinary, component of dark matter has been determined by measuring the abundance of elements heavier than hydrogen that were created in the first few minutes after the big bang occurred 13.8 billion years ago.
The dark matter that comprises the other 22 percent of the universe’s matter is in an unfamiliar, nonbaryonic form. The rate at which galaxies and large structures composed of galaxies coalesced from density fluctuations in the early universe indicates that the nonbaryonic dark matter is relatively “cold, ” or “nonrelativisitic, ” meaning that the backbones of galaxies and clusters of galaxies are made of heavy, slow-moving particles. The absence of from these particles also indicates that they are electromagnetically neutral. These properties give rise to the particles’ common name, weakly interacting massive particles (WIMPs). The precise nature of these particles is not currently known, and they are not predicted by the standard model of particle physics. However, a number of possible extensions to the standard model such as supersymmetric theories predict hypothetical elementary particles such as axions or neutralinos that may be the undetected WIMPs.
Extraordinary efforts are under way to detect and measure the properties of these unseen WIMPs, either by witnessing their impact in a laboratory detector or by observing their annihilations after they collide with each other. There is also some expectation that their presence and mass may be inferred from experiments at new particle accelerators such as the Large Hadron Collider.how do i delete myinbox helper How to get custom ringtones on iphone? How do you study tips or tricks or techniques? Screenwriting tricks for authors who publishes? How to talk to anyone: 92 little tricks for big success in relationships pdf? What does rainbow baby mean? Tips what you never have to share from your computer? What does a female blue jay look like? What does dominate mean? which cells produce antibodies? helper t suppressor t cytotoxic t natural killer b How to delete contacts on iphone fast? How to do funny magic tricks? How long to stay in sauna? How to lose 10 lbs in a week? How to change tips on mixoo stylus? When i heard "my finger tips and my lips they burn from the cigarettes" i was hooked? What tricks should dogs learn in order? How to refinance student loans? How long does it take pluto to orbit the sun? What is the meaning of surety? How to duplicate remembrance? What does succinctly mean? What year is it in the jewish calendar? What is the biblical meaning of 6666? What is the meaning of mama in english? How to remove nail tips at home? How to breed grumpyre? What are spoil tips? Hostel living tips for what to bring? How to make box cake better? What does battle a fashion challenger mean pokemon go? How to fix french tips nails? What are yo yo tricks string trick (1a, 3a, 5a)? How can wake up tips morning? Tips on how to level up quick in ark? What are plastids? How to clean a microwave? What does the fire emoji mean on snapchat? What are duck boots? How to witcher 3 early game tips and tricks? What are yhe? What time does outer banks come out on netflix? How to calculate rate of return? What does dense mean? How to tighten skin after weight loss naturally? What does lgbtqia+ means? who was the main helper of ramsey in the battle of the bastards How to find your moon sign? What are the factors of 36? How to make brown rice? How to get sober fast? Why is my plant have brown tips? What is the meaning of biographical sketch? What is the meaning of the name shanice? How to block scam likely calls? Tips when working for lyft in los angeles? How to help high blood pressure? How to cook crab legs in the oven? How to add airpods to find my iphone? What does smb mean in text? How to start a conclusion? How do you account for tips in quickbooks? What does defeat mean? What is quid pro quo? What is the meaning of life the universe and everything? What does a medical assistant do? How to become a notary in ohio? What does savannah mean? What is gelatin? Drip tips for vapes that make a custom sounds when smoked? What is the meaning of seeing a crow? What does epoch mean? How to lose a guy in 10 days yellow dress? What does distilled water mean? What does 🍆 mean? How to turn off low data mode? How to do dymamo magic tricks? What does versatile mean? Tips from couple who paid off debt? what is google chrome helper gpu mac How to get spray paint off concrete? Bbc how to interview tips and tricks? How to make money as a 14 year old? What is the meaning of instructor? mugen how to reverse helper projectiles How to do gun tricks rdr2 ps4? What is the meaning behind eminem's song stan? How to grill salmon? What does a rose quartz mean? How to.teach a dog tricks? What does libra mean? How long does it take to become a psychiatrist? how to use mark of the legion helper What does kimmy head mean? What does prideful mean in the bible? What kind of drug test does amazon do 2021? How to unlock a car door without a key? What is the meaning of the japan flag? How deep to plant tulip bulbs? What covid vaccine does walgreens have? Who to do card tricks? What is the meaning of revelation 13? What is a twin flame? What does d1 mean in sports? How to install butcher block countertops? What are the symptoms of diabetes? What does tone deaf mean? What is sku meaning? How to change decorating tips with a different frosting? how to make hambuger helper How to get rid of ticks in yard? How long to boil water? how to cook two boxes of philly cheesesteak hamburger helper What does amazon prime day mean? What are t cells and b cells? What does it mean when check engine light comes on? What does khair mubarak meaning in english? How to land clean tricks in tony hawk? which molecule of the surface of helper t-cells can provide signal #2 to activate b-cells? How to do the tricks hobby in sims freeplay? What is the meaning of the mexican flag eagle? What does green snot mean? What does sdn stand for? What does the suffix ment mean? What does it mean when you bite your tongue? How to protect catalytic converter? What does a beard mean? What does commotion mean? How to test a relay? How to relieve trapped gas? How to air fry potatoes? What are some tricks to play on senior adults for halloween? How to unlock my phone? What is tylenol? How to take a screenshot on desktop? How to increase your metabolism? What are the benefits of elderberry? How to make free call with out using app need tricks? What is the meaning of fourth of july? What noise does a bunny make? What is the symbolic meaning of an owl? Guy who does magic tricks on vine? How to report tips for self employed income? What does bios stand for? How to make myself sneeze? How to make buttermilk substitute? What are the 10 safety tips for swimming? How to make books in minecraft? how to get rid of coogle chrom helper How to find average velocity? Unite the right charlottesville how to dress tips? How to regain sense of smell and taste? How to mark all emails as read gmail? How can you enter sales tips when you are not tipping your employees? What is abs? how to install wii u usb helper youtube Tips and tricks on how to beat heroine undertale? How to grow rhubarb? What does lol dolls stand for? What does an all black american flag mean? How to get thicker thighs? How long to smoke whole chicken? but if you touch my hamburger helper i don't know what i might do What are the free masons? Why are the tips of my fingernails cracking? What does pull out mean? How in tarnation meaning? What maiden name meaning? What is the meaning of into the unknown? Who are you song meaning? What size ear tips should i use? How to style curly hair men? What does it mean when a dog eats grass? How to transfer money from bank to bank? Yale resume tips for when you are creating a job for yourself? How to play sudoku? How to become a twitch affiliate? How to record cash tips in quickbooks payroll? How to share my google calendar? What level does vulpix evolve? What does frost do in elden ring? What does begotten mean? How long to cook steak tips in the oven? What is a ssn? Amazing tricks for your girl when you eat her pussy? Where is greenwich mean time? How to tell if a cut is infected? How to get global entry? what goes with hamburger helper what is web helper and why does it use so much data What does it mean when you smoke a cigarette and your finger tips start tingling? how to make imitation hamburger helper beef noodles What does apres ski meaning? what is the term bird dog name for helper What are bifocal glasses? what does a driver helper do for ups How to craft a saddle in minecraft? Tricks to try when the lower right side of a kitchen cabinet is sagging lower? What is the meaning of microwave oven? What does surreal mean? How to get free stuff on amazon? How to skate tricks? When my heart is overwhelmed lead me to the rock that is higher than i meaning? How long to recover from wisdom teeth removal? What age to teach a puppy tricks? What is the meaning of case study? How to gain weight with fast metabolism? How to make breakout rooms in zoom? What is shake it about? What is the equation for photosynthesis? How to buy a house with bad credit? how to get tutu helper on my mac What does tsundere mean? What are you up to today meaning? What happened to jack halford in season 9 new tricks? what is the lowest level of t helper cells a person can have before being diagnosed with aids? What are tips in restaurants? what everyday tasks can helper monkeys halp with What does covered mean? How many freeestyle tricks did kevin jones invent? How to make an ender chest? How to connect chromecast to wifi? What is the meaning of intuitive? How to clean a record? How to buy solana? How to read auras? How to take baseball tips off football cleats? When a woman cuts her hair meaning? What does a yellow light mean? How to use google pay? What does it mean to be vain? How to get your teeth white? How to make gluten free bread? what is the file helper on wechat What does rosacea look like? What is the metal clip puzzlwith vinyl tips in a puzzle? How to get free spins on coin master? What does the red flag mean? What is the meaning of percentage? What does reset encrypted data mean? How to grow raspberries? What does it feel like to be pregnant? How to eat sunflower seeds? How to get a second phone number? What stage of cancer does techno have? How to reset password? Dark souls 3 guy who tricks you? How to teach guinea pigs to do tricks? What is the meaning of cultural competence? What does bipolar look like? What are some tips for adhd people to study for a & p? mother's little helper what a drag it is growing old What does proposition mean? What does a low standard deviation mean? How to do black panther tricks? Counseling tips for someone who wants to transition? How to the clairvoyants do the tricks? What does blowjob mean? What does otw mean? What does renovated mean? What does poco mean in spanish? What is one way that congress has clarified the meaning of the constitution? What does afk? What does nuclear high alert mean? How many hat tricks does drogba have? What is the meaning of this meme?
What astronomical evidences exist to disprove dark matter theory?
There is currently much ongoing research by scientists attempting to discover exactly what dark matter is.