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Common Physics Misconceptions

Related:  DIDACTIQUEQuantum ShenanigansExposições

World’s First Perpetual Motion Machine? Can this machine operate forever? Since at least the 12th century, man has sought to create a perpetual motion machine; a device that would continue working indefinitely without any external source of energy. A large scientific contingent thinks such a device would violate the laws of thermodynamics, and is thus impossible. Could it be that as a race, we don’t fully understand the laws of physics and such a device may indeed be possible? What would the ramifications be if we could actually build a perpetually moving device?

Measuring the Universe: from the transit of Venus to the edge of the cosmos : In June 2012 stargazers will flock to prime locations around the world to see the Transit of Venus – the next one will not occur for another 105 years. Transits take place only when Venus passes directly between the Earth and the Sun, appearing as tiny black dot against the bright solar disk. In previous centuries these rare events were used to make an accurate measure of the distance to the planets, giving astronomers their first inkling of the true mind-boggling scale of space. To mark this occasion the Royal Observatory, Greenwich will host a programme of activities from March to September 2012, with a new exhibition and a season of talks, special events and planetarium shows all asking the question: just how big is the Universe? From Edmund Halley and Captain Cook, to Edwin Hubble and the Cosmic Microwave Background, the Royal Observatory will tell the stories of the people who measured the cosmos.

An Idiot's Guide to Teleportation » SciFi Ideas / SciFi Ideas With contributor Harel Dor recently sharing with SciFi Ideas a story idea that makes full use of teleportation technology – Meet the Beamies – I thought it was high time we discussed teleportation in detail. Teleportation is one of science fiction’s most fascinating and useful ideas, being both a cool gadget and a clever narrative device; however, with lots of talk about quantum entanglement, ideas about how teleportation might actually be achieved can also be very complex. To help you understand what the science geeks are talking about and dispel some of the myths about the reality of teleportation, here’s an idiot’s guide to what this word actually means.

NASA Probes Play the Music of Earth’s Magnetosphere Want to stay on top of all the space news? Follow @universetoday on Twitter Launched on August 30, 2012, NASA’s twin Radiation Belt Storm Probe (RBSP) satellites have captured recordings of audible-range radio waves emitted by Earth’s magnetosphere. The stream of chirps and whistles heard in the video above consist of 5 separate occurrences captured on September 5 by RBSP’s Electric and Magnetic Field Instrument Suite and Integrated Science (EMFISIS) instrument. The events are presented as a single continuous recording, assembled by the (EMFISIS) team at the University of Iowa and NASA’s Goddard Space Flight Center. Physicists Achieve Quantum Teleportation of Photon Over 25 Kilometers For the first time, a team of physicists have successfully teleported a quantum state of a photon to a crystal over 25 kilometers away through a fiber optic cable. This effectively showed that the photon’s quantum state, not its composition, is important to the teleportation process. The team was led by Nicolas Gisin of the University of Geneva and the results were published in the journal Nature Photonics. With this new paper, Gisin’s team has successfully squashed the previous record they set a decade ago by teleporting a quantum state of a proton 6 kilometers. The quantum state of the photon is able to preserve information under extreme conditions, including the difference between traveling as light or becoming stored in the crystal like matter.

Universe at your fingertips - 3D prints of Hubble photos let the blind 'see' NGC 609 is one of the many small galactic star clusters located in the Milky Way in Cassiopia. It shines at magnitude 11.0, is 4 arc minutes in diameter and contains over 100 stars. Photo: Hubble telescope. Captioned above is one of Hubble‘s most famous and beautiful space photos. The photo features NGC 609 – a magnificent star cluster, which Hubble captured complete with colored gas, dust and a slew of stars of various brightness. Pictures like these remind people of the tremendous gift they have – sight. Hawking Radiation Recreated In A Laboratory A researcher claims to have produced a simulation of Hawking radiation, which if true will give physicists the chance to test one of Stephen Hawking's most significant predictions. In 1974, Hawking upended ideas about black holes with his theory that just outside the event horizon, particle-antiparticle pairs should appear as a result of the black hole's gravitational field. One of these would be drawn into the hole, but the other escape. Since the appearance of the pair draws energy from the hole and only half of this is recaptured, the effect is to reduce the hole's mass, causing it to eventually evaporate. Hawking's equations have won widespread support from physicists, and are a major contributor to his reputation.

What makes a halo around the sun or moon? A ring or circle of light around the sun or moon is called a halo by scientists. We get many messages throughout each year from people who’ve just spotted a ring around the sun or moon. People want to know: what causes a halo around the sun or moon?