Tag Archives | Physics

Sunsets On Alien Planets

alien sunsetA simulated sunset from a foreign solar system — what a dreamy dusk. PhysOrg writes:

Professor Frederic Pont, of the University of Exeter, imagined what it might really look like if a person were able to visit another planet and to then sit quietly watching as the sun set. He used data from a camera onboard Hubble, knowledge of how the color of light changes based on chemicals it encounters, and computer modeling, to create an actual image of what a sunset on an actual planet far out in space would look like. The planet in question, exoplanet HD209458b, nicknamed Osiris, just happens to be quite large and circles its star rather closely.

Though we couldn’t technically sit on the surface of Osiris, since it doesn’t have one, the picture that Pont produced approximates what it would look like, and the results are truly beautiful. The light from Osiris’s star is white, like our own sun, but when it passes through the sodium in Osirisi’s atmosphere, red light in it is absorbed, leaving the starlight to appear blue.

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Our Sun Is This Small (Animation)

Canis MajorisFor those of you who hated this proposed Earth-centric view of our Solar System, check out this video below. (VY Canis Majoris RULES for now; Giordano Bruno would be proud …):

VY Canis Majoris is a red hypergiant star located in the constellation Canis Major. At between 1800 and 2100 solar radii (8.4–9.8 astronomical units, 3.063 billion km or 1.7 billion miles in diameter), it is currently the largest known star and also one of the most luminous known …

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Earth (Usually) Has Two Moons

Two MoonsSo reports MIT’s Technology Review:

Back in 2006, the Catalina Sky Survey in Arizona noticed that a mysterious body had begun orbiting the Earth. This object had a spectrum that was remarkably similar to the titanium white paint used on Saturn V rocket stages and, indeed, a number of rocket stages are known to orbit the Sun close to Earth.

But this was not an object of ours. Instead, 2006 RH120, as it became known, turned out to be a tiny asteroid just a few metres across–a natural satellite like the Moon. It was captured by Earth’s gravity in September 2006 and orbited us until June 2007 when it wandered off into the Solar System in search of a more interesting neighbour.

2006 RH120 was the first reliably documented example of a temporary moon …

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There’s No Such Thing As Empty Space

sparkle03There’s always something, says a Swedish study. Phenomenica reports:

Scientists claim to have produced particles of light out of vacuum, proving that space is not empty.

An international team says that its ingenious experiment in which tiny parcels of light, or photons, are produced out of empty space has confirmed that a vacuum contains quantum fluctuations of energy, the ‘Nature’ journal reported.

In fact, the scientists have demonstrated for the first time a strange phenomenon known as the dynamical Casimir effect, or DCE for short.

The DCE involves stimulating the vacuum to shed some of the myriad “virtual” particles that fleet in and out of existence, making them real and detectable. Moreover, the real photons produced by the DCE in their experiment collectively retain a peculiar quantum signature that ordinary light lacks.

The research, led by Chris Wilson of Chalmers University of Technology in Sweden, shows that a related dynamic effect can occur when such a mirror moves very fast through the vacuum.

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God Particle Proves Elusive

CMS_41For those of you following the “God Particle” saga, the scientists at CERN disappointed us all at today’s much hyped news conference. Nick Collins reports for the Telegraph:

At a specially-arranged seminar at the Cern laboratory in Geneva, researchers presented clues in their data which suggest experts may have pinned down the “God particle” at last.

Scientists remained cautious about their findings and insisted they did not represent an official discovery, but admitted the results were “intriguing”.

The two teams searching for the Higgs boson at the LHC said they had found hints which point towards a Higgs boson with a mass between 124 and 126 gigaelectronvolts (GeV).

A mass of 125 GeV is equivalent to about 130 times the weight of a proton found in the nucleus of an atom.

The team working on the ATLAS detector said there was only a one per cent likelihood their results occurred by chance rather than reflecting a real effect, while the CMS team quoted a figure of about five per cent.

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A Glimpse Of The God Particle

A simulated event in the CMS detector, featuring the appearance of the Higgs boson. (CERN)

A simulated event in the CMS detector, featuring the appearance of the Higgs boson. (CERN)

As an update to this post, physicists the world over are all ashiver at the prospect of the elusive Higgs boson particle being announced tomorrow. Via ExtremeTech:

Tomorrow, at 9am EST, scientists at the Large Hadron Collider (LHC) at CERN in Switzerland are expected to announce, with fairly strong certainty, that they have observed the Higgs boson “God” particle at a mass-energy of 125 GeV.

For just over a week, rumors have been rife that observations with 2.5 to 3.5 sigma certainty (96% to 99.9%) have been made. For it to be declared an actual discovery, however, a sigma level of five has to be recorded. A score on the higher end of the range, towards 3.5, would definitely have particle physicists, engineers, scientists, and philosophers jumping around excitedly, though. Perhaps more importantly, LHC has two detectors at the end of its 17-mile-long particle acceleration tunnel, and both have reportedly seen the Higgs boson: the CMS detector with sigma 2.5, and ATLAS with sigma 3.5.

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Has the “God Particle” (the Higgs Boson) Been Discovered?

HiggsDavide Castelvecchi reports in Scientific American:

Rumors are flying about a December 13 update on the search for the long-sought Higgs boson at Europe’s Large Hadron Collider.

The physics buzz reached a frenzy in the past few days over the announcement that the Large Hadron Collider in Geneva is planning to release what is widely expected to be tantalizing — although not conclusive — evidence for the existence of the Higgs boson, the elementary particle hypothesized to be the origin of the mass of all matter.

Many physicists have already swung into action, swapping rumors about the contents of the announcement and proposing grand ideas about what those rumors would mean, if true. “It’s impossible to be excited enough,” says Gordon Kane, a theoretical physicist at the University of Michigan at Ann Arbor.

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Time Reversal: A Simple Particle Could Reveal New Physics

Time ReversalShelley Littin writes in Space Daily:

A simple atomic nucleus could reveal properties associated with the mysterious phenomenon known as time reversal and lead to an explanation for one of the greatest mysteries of physics: the imbalance of matter and antimatter in the universe.

The physics world was rocked recently by the news that a class of subatomic particles known as neutrinos may have broken the speed of light.

Adding to the rash of new ideas, University of Arizona theoretical physicist Bira van Kolck recently proposed that experiments with another small particle called a deuteron could lead to an explanation for one of the most daunting puzzles physicists face: the imbalance of matter and antimatter in the universe. A deuteron is a simple atomic nucleus, or the core of an atom. Its simplicity makes it one of the best objects for experiments in nuclear physics …

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CERN’s Neutrinos Travel Faster Than Speed Of Light

EinsteinScientists making discoveries that defy the laws of physics seems to be something of a theme this month. Now the eggheads at CERN say they’ve observed subatomic particles moving faster than the speed of light, which might theoretically allow us to travel back in time. Eryn Brown and Amina Khan report for the LA Times:

Albert Einstein had the idea. A century of observations have backed it up. It’s one of the cornerstones of physics: Nothing travels faster than the speed of light.

But now a team of experimental physicists at the European Organization for Nuclear Research, known as CERN, says that one exotic particle possibly can.

The scientists reached their conclusion after sending streams of tiny, subatomic particles called neutrinos hurtling from an accelerator at CERN outside Geneva to a detector at the Gran Sasso National Laboratory in Italy, about 450 miles away.

The neutrinos seemed to get there too soon — 60 nanoseconds too soon, give or take — than they should if they’d been traveling at the speed of light.

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