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Dark Energy, Dark Matter

Dark Energy, Dark Matter
Dark Energy, Dark Matter In the early 1990s, one thing was fairly certain about the expansion of the Universe. It might have enough energy density to stop its expansion and recollapse, it might have so little energy density that it would never stop expanding, but gravity was certain to slow the expansion as time went on. Granted, the slowing had not been observed, but, theoretically, the Universe had to slow. The Universe is full of matter and the attractive force of gravity pulls all matter together. Then came 1998 and the Hubble Space Telescope (HST) observations of very distant supernovae that showed that, a long time ago, the Universe was actually expanding more slowly than it is today. Eventually theorists came up with three sorts of explanations. What Is Dark Energy? More is unknown than is known. One explanation for dark energy is that it is a property of space. Another explanation for how space acquires energy comes from the quantum theory of matter. What Is Dark Matter?

http://science.nasa.gov/astrophysics/focus-areas/what-is-dark-energy/

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CoP - Using Astronomy as an aid to teaching STEM The idea for this CoP, simply called “Using Astronomy as an aid to teaching STEM”, came from many interactions with schools and their teachers and culminating in the inGenious astronomy chat that involved 35 schools from across Europe in December 2012. Astronomy is a great way to “package” ideas, and understanding the universe naturally requires teachers and students to ask questions that involve all the STEM subjects, and even some non-STEM subjects. This CoP will encourage teachers to look at new ways to present some old ideas, using the fast-changing face of astronomy to provide the context.

Dark Energy: The Biggest Mystery in the Universe Twice a day, seven days a week, from February to November for the past four years, two researchers have layered themselves with thermal underwear and outerwear, with fleece, flannel, double gloves, double socks, padded overalls and puffy red parkas, mummifying themselves until they look like twin Michelin Men. Then they step outside, trading the warmth and modern conveniences of a science station (foosball, fitness center, 24-hour cafeteria) for a minus-100-degree Fahrenheit featureless landscape, flatter than Kansas and one of the coldest places on the planet. They trudge in darkness nearly a mile, across a plateau of snow and ice, until they discern, against the backdrop of more stars than any hands-in-pocket backyard observer has ever seen, the silhouette of the giant disk of the South Pole Telescope, where they join a global effort to solve possibly the greatest riddle in the universe: what most of it is made of. But what if some portion of a galaxy’s mass didn’t radiate light?

Dark matter Dark matter is invisible. Based on the effect of gravitational lensing, a ring of dark matter has been detected in this image of a galaxy cluster (CL0024+17) and has been represented in blue.[1] Dark matter is a hypothetical kind of matter that cannot be seen with telescopes but accounts for most of the matter in the universe. The existence and properties of dark matter are inferred from its gravitational effects on visible matter, radiation, and the large-scale structure of the universe. Other than neutrinos, a form of hot dark matter, it has not been detected directly, making it one of the greatest mysteries in modern astrophysics. Astrophysicists hypothesized dark matter because of discrepancies between the mass of large astronomical objects determined from their gravitational effects and the mass calculated from the observable matter (stars, gas, and dust) that they can be seen to contain.

Meet Joe Incandela, Higgs boson Physicist Joe Incandela announced the discovery of the Higgs boson on July 4, 2012. The mosaic of photos of colleagues spells "CMS," which stands for Compact Muon Solenoid. CMS is one of the experiments at the Large Hadron Collider that detected the particle. The Large Hadron Collider is located at CERN, the European Organization for Nuclear Research, near Geneva, Switzerland. Martin White: Dark Matter We believe that most of the matter in the universe is dark, i.e. cannot be detected from the light which it emits (or fails to emit). This is "stuff" which cannot be seen directly -- so what makes us think that it exists at all? Its presence is inferred indirectly from the motions of astronomical objects, specifically stellar, galactic, and galaxy cluster/supercluster observations. It is also required in order to enable gravity to amplify the small fluctuations in the Cosmic Microwave Background enough to form the large-scale structures that we see in the universe today. For each of the stellar, galactic, and galaxy cluster/supercluster observations the basic principle is that if we measure velocities in some region, then there has to be enough mass there for gravity to stop all the objects flying apart. When such velocity measurements are done on large scales, it turns out that the amount of inferred mass is much more than can be explained by the luminous stuff.

Kepler: Educator Web Links Educator Web Links Oct 2011: Agent Exoplanet—Astronomers at Las Cumbres Observatory are investigating exoplanets and you can too. Through Agent Exoplanet you use images taken by Las Cumbres Observatory Global Telescope Network (LCOGT), measure the brightness of a star while a planet moves between it and our viewpoint (exoplanet transit event), and contribute to understanding the properties of each exoplanet. Things to put on your computer to stay up-to-date on exoplanet discoveries: NASA Sites Spacemath@NASA introduces students to the use of mathematics in relation to scientific discoveries announced in NASA press releases and other articles, Created and maintained by Dr.

Dark matter Dark matter is invisible. Based on the effect of gravitational lensing, a ring of dark matter has been inferred in this image of a galaxy cluster (CL0024+17) and has been represented in blue.[1] Dark matter is a hypothetical kind of matter that cannot be seen with telescopes but accounts for most of the matter in the universe. The existence and properties of dark matter are inferred from its gravitational effects on visible matter, on radiation, and on the large-scale structure of the universe. Dark matter has not been detected directly, making it one of the greatest mysteries in modern astrophysics. Tentative dark matter hits fit with shadow dark sector - physics-math - 16 April 2013 Deep in Minnesota's Soudan mine, the invisible stuff thought to make up about 80 per cent of the universe's matter may finally have made an appearance. Though the latest dark matter signal is still too weak to claim a discovery, it matches another from the same mine. Meanwhile, its energy fits with a host of recent theories that suggest dark matter is not a single entity, but a dark sector of particles that could include dark antimatter.

Angels & Demons - The science behind the story The term 'The God particle' was coined by the physicist Leon Lederman in his 1993 popular science book, The God Particle: If the Universe Is the Answer, What Is the Question? The particle that the book title refers to is the 'Higgs boson'. The particle we now call the Higgs boson has never been observed. How Dark Matter Works" In the 1978 follow-up album to "Born to Run," Bruce Springsteen uses darkness on the edge of town as a metaphor for the desolate unknown we all face as we grow up and try to understand the world. Cosmologists working to decipher the origin and fate of the universe must identify completely with The Boss' sense of tragic yearning. These stargazing scientists have been facing their own darkness on the edge of town (or on the edge of galaxies) for a long time as they try to explain one of astronomy's greatest mysteries. It's known as dark matter, which is itself a placeholder – like the x or y used in algebra class – for something unknown and heretofore unseen.

A Newly Confirmed Planet and 42 Additional Planet Candidates « Planet Hunters Artistic rendition of a sunset viewfrom the perspective of an imagined Earth-like moon orbiting the giant planet, PH2 b. Image Credit: H. Giguere, M. Giguere/Yale University We are pleased to announce the discovery and confirmation of our second confirmed planet : PH2 b-a Jupiter-size planet in the habitable zone of a star like the Sun-by the Planet Hunter project. Big Bang According to the Big Bang model, the universe expanded from an extremely dense and hot state and continues to expand. Since Georges Lemaître first noted, in 1927, that an expanding universe might be traced back in time to an originating single point, scientists have built on his idea of cosmic expansion. While the scientific community was once divided between supporters of two different expanding universe theories, the Big Bang and the Steady State theory, accumulated empirical evidence provides strong support for the former.[8] In 1929, from analysis of galactic redshifts, Edwin Hubble concluded that galaxies are drifting apart, important observational evidence consistent with the hypothesis of an expanding universe.

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