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Top 10 Strangest Things in Space The universe is a weird place. Here’s a look at some of the strangest things in the cosmos. Antimatter Like Superman’s alter-ego, Bizzaro, the particles making up normal matter also have opposite versions of themselves. An electron has a negative charge, for example, but its antimatter equivalent, the positron, is positive. Matter and antimatter annihilate each other when they collide and their mass is converted into pure energy by Einstein’s equation E=mc2. Some futuristic spacecraft designs incorporate anti-matter engines. Mini-Black Holes If a radical new “braneworld” theory of gravity is correct, then scattered throughout our solar system are thousands of tiny black holes, each about the size of an atomic nucleus. Unlike their larger brethren, these mini-black holes are primordial leftovers from the Big Bang and affect space-time differently because of their close association with a fifth dimension. Cosmic Microwave Background Also known as the CMB, this radiation is a primordial leftover from the Big Bang that birthed the universe. It was first detected during the 1960s as a radio noise that seemed to emanate from everywhere in space. The CMB is regarded as one of the best pieces of evidence for the theoretical Big Bang. Recent precise measurements by the WMAP project place the CMB temperature at -455 degrees Fahrenheit (-270 Celsius). Dark Matter Scientists think it makes up the bulk of matter in the universe, but it can neither be seen nor detected directly using current technologies. Candidates range from light-weight neutrinos to invisible black holes. Some scientists question whether dark matter is even real, and suggest that the mysteries it was conjured to solve could be explained by a better understanding of gravity. Exoplanets Until about the early 1990s, the only known planets in the universe were the familiar ones in our solar system. Astronomers have since identified more than 500 extrasolar planets (as of November 2010). They range from gargantuan gas worlds whose masses are just shy of being stars to small, rocky ones orbiting dim, red dwarfs. Searches for a second Earth, however, are still ongoing. Astronomers generally believe that better technology is likely to eventually reveal worlds similar to our own. Gravity Waves Gravity waves are distortions in the fabric of space-time predicted by Albert Einstein’s theory of general relativity. The gravitational waves travel at the speed of light, but they are so weak that scientists expect to detect only those created during colossal cosmic events, such as black hole mergers like the one shown above. LIGO and LISA are two detectors designed to spot the elusive waves. Galactic Cannibalism Like life on Earth, galaxies can “eat” each other and evolve over time. The Milky Way’s neighbor, Andromeda, is currently dining on one of its satellites. More than a dozen star clusters are scattered throughout Andromeda, the cosmic remains of past meals. The image above is from a simulation of Andromeda and our galaxy colliding, an event that will take place in about 3 billion years. Neutrinos Neutrinos are electrically neutral, virtually mass-less elementary particles that can pass through miles of lead unhindered. Some are passing through your body as you read this. These “phantom” particles are produced in the inner fires of burning, healthy stars as well as in the supernova explosions of dying stars. Detectors are being embedded underground, beneath the sea, or into a large chunk of ice as part of IceCube, a neutrino-detecting project. Quasars These bright beacons shine to us from the edges of the visible universe and are reminders to scientists of our universe’s chaotic infancy. Quasars release more energy than hundreds of galaxies combined. The general consensus is that they aremonstrous black holes in the hearts of distant galaxies. This image is of quasar 3C 273, photographed in 1979. Vacuum Energy Quantum physics tells us that contrary to appearances, empty space is a bubbling brew of “virtual” subatomic particles that are constantly being created and destroyed. The fleeting particles endow every cubic centimeter of space with a certain energy that, according to general relativity, produces an anti-gravitational force that pushes space apart. Nobody knows what’s really causing the accelerated expansion of the universe, however.
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8 čuda svemira Svemir još uvijek predstavlja riznicu tajni i misterija za čovječanstvo. Neke od njih vam ipak predstavljamo Antimaterija - poput alter-ega superheroja, čestice koje tvore normalnu materiju također imaju svoje suprotne verzije. Elektron ima negativan naboj, ali njegov ekvivalent u obliku antimaterije, tj. pozitron, ima pozitivan. Materija i antimaterija se poništavaju ukoliko dođe do kolizije, a njihova masa se pretvara u čistu energiju. Neki futuristički svemirski brodovi koriste za pogon motore koji rade na ovom principu. Mini crne rupe - ukoliko je nova "brane" teorija gravitacije točna, onda je naš Sunčev sustav prepun sičušnih crnih rupa, od kojih je svaka veličine atomske jezgre. Za razliku od njihovih većih srodnika, ove mini crne rupe zapravo su ostaci Velikog praska, te utječu drugačije na prostor i vrijeme zbog svoje bliske povezanosti s 5 dimenzijom. Kozmičko pozadinsko zračenje - ova vrsta radijacije također je ostatak Velikog praska. Prvi je put otkrivena tijekom 1960-tih kao radio buka koja dolazi iz dubokog svemira. Kozmičko pozadinsko zračenje jedan je od najboljih primjera dokaza za teoretski Veliki prasak. Posljednja precizna mjerenja pokazuju da temperatura ovog zračenja iznosi -270 stupnjeva Celzijusa. Tamna tvar - znanstvenici smatraju kako je od nje sačinjen svemir, no ne može se vidjeti ili detektirati pomoću trenutne tehnologije. Kandidati za ovu tvar rangiraju od laganih neutrina, pa do nevidljivih crnih rupa. Neki znanstvenici sumnjaju da tamna tvar uopće postoji, te sugeriraju kako bi se ova misterija trebala riješiti boljim shvaćanjem gravitacije. Gravitacijski valovi - radi se o pomacima u prostorno-vremenskom kontinuumu koje predviđa Einsteinova opća teorija relativnosti. Gravitacijski valovi putuju brzinom svjetlosti, no toliko su slabi da znanstvenici smatraju kako mogu otkriti samo one koji su nastali tijekom velikih kozmičkih događaja, poput spajanja dviju crnih rupa. LIGO i LISA dva su detektora napravljena da prepoznaju ovu vrstu valova. Galaktički kanibalizam - galaksije mogu "jesti" jedna drugu i evoluirati tijekom vremena. Susjed naše galaksije, Andromeda, trenutno "jede" jedan od svojih satelita. Deseci jata zvijezda razbacani su kroz Andromedu, što su ostaci prošlih obroka. Mliječna staza i Andromeda također bi trebali doći u koliziju, što je događaj koji će se zbiti za oko 3 milijarde godina. Neutrini - radi se o električki neutralnim, gotovo bez mase, elementarnim česticama koje mogu proći kroz kilometre olova neometano. Neke prolaze kroz vaše tijelo dok ovo čitate. Ove fantomske čestice proizvode jezgre zdravih zvijezda kao i eksplozije supernova. Vakumska energija - kvantna fizika tvrdi da unatoč svojem izgledu, prazan prostor vrvi "virtualnim" subatomskim česticama koje se stalno stvaraju i uništavaju. Ove čestice ispunjavaju svaki kubni centimetar svemira određenom energijom, koja, kako navodi opća teorija relativnosti, stvara antigravitacijsku silu koja širi svemir. Untaoč tome, još se ne zna što točno uzrokuje ubrzano širenje svemira.