The results of repeat Neutrino experiment

The team which found that neutrinos may travel faster than light has carried out an improved version of their experiment - and confirmed the result.

If confirmed by other experiments, the find could undermine one of the basic principles of modern physics.

Critics of the first report in September had said that the long bunches of neutrinos (tiny particles) used could introduce an error into the test.

The new work used much shorter bunches.

It has been posted to the Arxiv repository and submitted to the Journal of High Energy Physics, but has not yet been reviewed by the scientific community.

The experiments have been carried out by the Opera collaboration - short for Oscillation Project with Emulsion (T)racking Apparatus.

It hinges on sending bunches of neutrinos created at the Cern facility (actually produced as decays within a long bunch of protons produced at Cern) through 730km (454 miles) of rock to a giant detector at the INFN-Gran Sasso laboratory in Italy.

The initial series of experiments, comprising 15,000 separate measurements spread out over three years, found that the neutrinos arrived 60 billionths of a second faster than light would have, travelling unimpeded over the same distance.

The idea that nothing can exceed the speed of light in a vacuum forms a cornerstone in physics - first laid out by James Clerk Maxwell and later incorporated into Albert Einstein's theory of special relativity. Initial analysis of the work by the wider scientific community argued that the relatively long-lasting bunches of neutrinos could introduce a significant error into the measurement.

Those bunches lasted 10 millionths of a second - 160 times longer than the discrepancy the team initially reported in the neutrinos' travel time.

To address that, scientists at Cern adjusted the way in which the proton beams were produced, resulting in bunches just three billionths of a second long.

When the Opera team ran the improved experiment 20 times, they found almost exactly the same result. The error in the length of the bunches, however, is just the largest among several potential sources of uncertainty in the measurement, which must all now be addressed in turn; these mostly centre on the precise departure and arrival times of the bunches.

"So far no arguments have been put forward that rule out our effect," Dr Ereditato said.

"This additional test we made is confirming our original finding, but still we have to be very prudent, still we have to look forward to independent confirmation. But this is a positive result."

That confirmation may be much longer in coming, as only a few facilities worldwide have the detectors needed to catch the notoriously flighty neutrinos - which interact with matter so rarely as to have earned the nickname "ghost particles".

Next year, teams working on two other experiments at Gran Sasso experiments - Borexino and Icarus - will begin independent cross-checks of Opera's results.

The US Minos experiment and Japan's T2K experiment will also test the observations. It is likely to be several months before they report back.

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Hubble Spots Disk Around Distant Black Hole

Many of the commentors below have wondered how this quasar can be 18.5 billion light-years away when the universe is only 13.5 billion years old (and therefore nothing should be farther than the distance that light would travel in that time, namely 13.5 billion light-years). This is not a mistake. Though nothing traveling in the universe can move faster than light speed, the expansion of the universe itself can happen at any speed (including faster than light). Just one of the mind blowing facts about this strange universe we live in.

In the 13.5 billion years since the Big Bang, space has expanded so much that the farthest object we can detect are in fact more than 30 billion light years away. You can find out more about the quasar at this link and you can calculate distance to objects at high redshifts using this online calculator. Using the Hubble space telescope, astronomers have captured a direct image of the disk surrounding a black hole.

The disk is made of gas and dust, slowly being consumed as it spirals down into the black hole’s center. As it falls in, the material spews out a tremendous amount of energy, forming what is known as a quasi-stellar radio source, or quasar.

Among the brightest objects in the sky, quasars are short-lived phenomena that only existed during the earliest eras of the universe. They are known to be huge — most are around 60 billion miles across — yet they lie billions of light years from Earth, making them nothing but insignificant pinpricks in even the most powerful telescopes.

Hubble was able to image the distant disk, which is approximately 18.5 billion light-years away, because a huge galaxy happens to sit between Earth and the quasar. The mass of the enormous galaxy bent light from the quasar and directed it toward our telescopes, acting like a gigantic gravitational lens.

The technique allowed the Hubble telescope to see with unprecedented detail. Because of this, researchers were able to measure the disk’s size — between 60 and 180 billion miles across — and determine the temperature of different parts of the disk. They found that gas and dust from the imaged quasar became bluer and therefore hotter as it fell toward the central black hole.

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Science Second mission to scale deep mountains announced

Scientists are set to begin a six-week mission to explore the Indian Ocean's underwater mountains.

Aboard the UK research vessel the RRS James Cook, the team will study animals thousands of metres below the surface.

This year a report in the journal Marine Policy found that deep sea trawling is one of the most damaging forms of fishing.

The expedition will help scientists to better understand the threats to this environment. The mission, led by the International Union for Conservation of Nature (IUCN), is the second to visit the seamounts along the South-West Indian Ocean Ridge; the first set out in November 2009.

Seamounts are underwater mountains which rise to at least 1,000 metres above the sea floor.
Seamount communities

"Because of their interactions with underwater currents, the biodiversity that develops around them is remarkably rich," explained Aurelie Spadone, IUCN's marine programme officer and a member of the team.

"They attract a great diversity of species and act as a type of 'bed and breakfast' for deep-sea predators such as sharks, which often feed on seamount communities," she added.  The catch of deep-sea species has increased seven-fold since the mid-1960s, as stocks of shallower waters plummet and the fishing industry took to exploiting deeper waters.

Industrial fishing at depth, which generally relies on trawling the ocean's bottom with huge weighted nets, has a huge impact on seafloor ecosystems, say researchers. Carl Gustaf Lundin, director of IUCN's Global Marine and Polar Programme explained that very little was known about the species associated with seamounts.

"Many of them grow and reproduce slowly, which makes them particularly vulnerable to overexploitation," he said.

"Deep-sea bottom fisheries, including bottom trawling, can damage seamount habitats and negatively impact fish stocks. It can also irreversibly damage cold water corals, sponges and other animals."

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