Posted on by Ian O'Neill

LHC Doomsday Lawsuit Finally Dismissed by Hawaii Judge

Particle Collider
Today, CERN announced that the LHCb experiment had revealed the existence of two new baryon subatomic particles. Credit: CERN/LHC/GridPP

[/caption]It’s official, the LHC lawsuit has been dismissed. After seven months of hype, media frenzy and hysteria about the non-existent risk associated with the Large Hadron Collider, Federal Judge Helen Gillmor said her Honolulu court lacked jurisdiction over the European-based CERN particle accelerator. This decision may have been a long-time coming, but at least we can all look forward to spring 2009’s delayed LHC experiments without a fantastical lawsuit hanging over the proceedings.

Although the suit, filed by Walter Wagner and Luis Sancho, was intended to discredit the science and safety behind the LHC, it turns out that it may have done exactly the opposite…

We have been following the LHC lawsuit with some interest on the Universe Today (just in case you hadn’t noticed). At first, the lawsuit seemed to be some kind of half-witted stunt, and it was treated as such. However, once the world realised that two guys in Hawaii really had filed a real lawsuit against the US partners in the European project, the media started to get interested. Questions of concern began to crop up, such as: What if Wagner is right? What if a black hole does swallow Earth after the first particle collisions? What’s going to happen if the LHC does spawn a choking hoard of strangelets?

But as the frenzy calmed and physicists started to formulate their own, more grounded, arguments against the lawsuit’s claims; the public started to investigate what all the fuss was really about. Then we started to get more inquisitive questions, such as: What actually is the Higgs Boson? What is the “Standard Model” and why is it important? What do you mean by “re-create the conditions shortly after the Big Bang”? Very quickly physicists realised that the LHC lawsuit – although clearly unhinged and fearful – could be used to their advantage. Excellent physics speakers such as Brian Cox became the centre of attention as the world’s minds turned to them for answers; the worlds biggest physics experiment suddenly became the topic of conversation in coffee shops and bars the world over.

Actually, this isn’t a bad thing…

Although picking holes in Wagner et al.’s theories was fun for a while, more media hype was on the horizon as the September 10th LHC “switch on” approached. I saw various mainstream media sources publishing horrendous articles predicting the end of the world in days, based purely on the speculative claims of Wagner’s legal action. (After all, fear sells.) However, through the hysteria, many sources were talking coherently and intelligently about what the LHC will do and what we hope to discover. For the first time in many years, a physics experiment was on the front page of every new paper, website and TV headline.

One of the plaintiffs, Luis Sancho, responded to Judge Gillmor’s decision and summed up the lawsuit fairly accurately. “The lawsuit was an unbelievable success in that it put the collider issue on the intellectual agenda,” he said in an email to the New York Times. Although he was referring to his “collider issue”, he is absolutely right that his actions helped to put the LHC on the “intellectual agenda.” For once, it looks like from all this doomsday hype, the LHC managed to generate huge positive interest, and with the patient safety reports and arguments put forward by CERN scientists, any fears were quickly subdued.

Back in the courtroom, Judge Gillmor rightly stated that Wagner’s suit was a “complex debate” of concern to the whole world, and not just physicists. If anything, at least this lawsuit did achieve one thing: it brought a complex physics experiment into the public domain so it could be debated. Plus it created some fantastic advertising ahead of the first (delayed) experiments early next year…

Source: NY Times

Posted on by Ian O'Neill

China’s First Spacewalk a Success (Video)

Zhai Zhigang exits the Shenzhou-7 capsule with Earth overhead (Xinhua/BBC)

[/caption]It’s official, China has become the third nation to successfully carry out a spacewalk in Earth orbit. Fighter pilot Zhai Zhigang was the first to exit the Shenzhou-7 module at 16:30 Beijing Time (08:30 GMT), as the Chinese space agency streamed live video of the event. Zhai lifted himself through the hatch and waved at the camera attached to the service module on the outside of the craft, with Earth looming overhead. Shortly after, crew mate Liu Boming emerged to hand Zhai a small Chinese flag which he waved enthusiastically. The extra-vehicular activity (EVA) lasted for about 15 minutes. At the start of the EVA, Zhai said, “I’m feeling quite well. I greet the Chinese people and the people of the world.”

Shenzhou-7 was launched by a Long March II-F rocket from Jiuquan Satellite Launch Center in the northwestern Gansu Province of China on Thursday, carrying Zhai Zhigang, Liu Boming and Jing Haipeng into space on the three-day mission. The principal objective was to successfully complete a spacewalk, paving the way for a Chinese orbital outpost and eventual mission to the Moon within the decade. It would appear the mission was a success, allowing China into an exclusive club of only three nations ever to have carried out orbital activities in a space suit.

Watch China’s first ever space walk »

Zhai and Liu wore a Chinese-designed spacesuit called “Feitian” (which literally translates as “Fly in the Sky”), thought to cost between £5m and £20m ($10m-$40m) apiece. The third taikonaut (or “yuhangyuan”) Jing Haipeng, remained inside Shenzhou-7 wearing a Russian-made Orlan suit.

Whilst outside the craft, attached via an umbilical cable, Zhai retrieved a test sample of solid lubricant attached to the outside of the module before they were launched. He passed the sample to Liu. Once the handover was complete, 16 minutes into the EVA, both men re-entered the capsule.

Zhai, now China’s first man to ever carry out an EVA in Earth orbit, will celebrate his 42nd birthday next month. Prior to enrolling in China’s manned space programme, he was an air force pilot, and before then the official Chinese news agency was keen to highlight that Zhai “grew up in dirt-poor hardship with five siblings in the country’s far northeast,” and he “dreamed of flying into space when he was an impoverished teenager.”

This is an amazing achievement that will only boost the space-faring confidence of the Chinese. Perhaps the first Chinese Moon base isn’t that far off after all…

Sources: BBC, Xinhua

Posted on by Ian O'Neill

Astrophysicist’s South Pole Death Remains a Mystery After Eight Years

Rodney Marks (1997-1998 winterover) with the SPIREX telescope (D. A. Harper)

[/caption]In May 2000, Australian astrophysicist Dr Rodney David Marks died from acute methanol poisoning whilst stationed at the US Amundsen-Scott South Pole Station. He was a 32 year old “brilliant and witty” scientist, whose death shocked his family and friends. The media jumped on this story, citing the tragedy as the “first South Pole murder,” but there was little evidence to suggest anyone else was involved. Unfortunately it appears that New Zealand investigators have been hampered by a lack of co-operation by the organizations that run the facility, so it remains unclear whether Marks’ death was the result of foul play or tragic accident…

Dr Marks was employed by the Smithsonian Astrophysical Observatory, working on the Antarctic Submillimetre Telescope and Remote Observatory project. The Amundsen-Scott South Pole Station (pictured below) is maintained by the US National Science Foundation (NSF) and US contractor Raytheon Polar Services, and is the southernmost continually inhabited settlement on Earth. With this exotic location comes a high degree of risk; after all, if there’s an accident or emergency, you can’t just find the nearest hospital. Although the facility has good medical support, should something unexpected happen, the scientists living right on top of the South Pole are at the mercy of the extreme weather and isolated location.

Aerial view the South Pole, including the Amundsen-Scott South Pole Station (NOAA)
Aerial view the South Pole, including the Amundsen-Scott South Pole Station (NOAA)

In the month of May 2000, medical staff at Amundsen-Scott were confronted with a baffling problem when a distressed Rodney Marks came to them three times during a 36 hour period. On May 11th, he had felt sick and vomited blood when travelling back from the remote observatory to base. On returning, his condition took a rapid turn for the worse. Baffled by the situation, medical staff sought advice via satellite, but they were too late. On May 12th, the astrophysicist had died.

For six months, officials had to wait until Marks’ body could be flown to New Zealand for an autopsy where it was found that the 32 year old had suffered from acute methanol poisoning. As New Zealand has jurisdiction over the incident, investigators from the nation took on the task of working out how Marks could have become poisoned.

According to a recent article in the New Zealand Herald, the investigators may never get to the bottom of this Antarctic mystery. On September 24th, coroner Richard McElrea released his findings behind the death of Dr Marks, airing his frustrations that the police investigation had been hampered by the lack of co-operation by the NSF and Raytheon Polar Services.

The police officer assigned to investigating the case, Detective Grant Wormald, even remarked, “Despite numerous requests, I am not entirely satisfied that all relevant information and reports have been disclosed to the New Zealand police or the coroner.” Dr Marks’ family have also been disappointed by the lack of communication they have received by the organizations responsible for the safety of their researchers.

“And I don’t think we are going to try to find out any more in regards to how Rodney died. I’d see that as a fruitless exercise […] For heaven’s sake, a man has died in your care. Why wouldn’t you help the police? .” – Paul Marks, Dr Marks’ father.

Originally, suicide was thought to be at the root of this mystery, but it was quickly ruled out as it didn’t fit with Dr Marks’ profile. He was a happy scientist who was engaged to Sonja Wolter, a young maintenance specialist, who had signed up to the station to be with her fiancé. According to the Detective Wormald, “Sonja and Rodney were a great couple. It is so rare to see people that seem so perfectly matched. And they were extremely happy together.”

It was also suggested that Marks may have consumed the methanol deliberately, to get a “recreational high,” even though there was a plentiful supply of genuine liquor and beer at the facility. Dr Marks was a social young man who “always said was that the solution to any problem is to go down to the pub and have a few drinks,” according to one of his friends, Andrew Walsh. Even though he may have enjoyed a few drinks and could be considered to be a binge drinker, it is strange to think he would willingly consume the dangerous substance for fun.

There are some sinister overtones to this mystery however. According to a 1996 report, Dr Robert Thompson, the first doctor to examine Marks when he came to the medical facility for help, said the astrophysicist was “nervous, anxious and upset.” What’s more, he noted two needle marks on his arm, but decided not to ask about them.

Had Marks been murdered by one of the 49 members of staff at the Amundsen-Scott South Pole Station? Unfortunately, we may never know whether Marks’ death was deliberate or by accident. According to the US agencies, an investigation had been carried out, but Detective Wormald has not been privy to the conclusions. “It is impossible to say how far that investigation went or to what end,” he said.

The Herald reporter apparently approached Raytheon, but the company would not comment and an NSF spokesman referred any questions to the NSF offices in Washington DC.

It looks like everyone is remaining tight-lipped about the events on May 11th-12th 2000, ensuring the world may never get to the cause behind the tragic death of this talented and friendly astrophysicist.

Sources: NZ Herald, Ohmynews.com, Wikipedia

Posted on by Ian O'Neill

Solar System’s Protective Shield is Weakening; Solar Wind Velocity at Record Low

The three Ulysses spacecraft orbits of the Sun. Figure shows radial solar wind velocity and images of the Sun at varying degrees of activity (McComas et al. GRL, 2008)

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Solar wind output is at its lowest since accurate records began 50 years ago. This finding comes from the seasoned ESA/NASA solar probe Ulysses, which completed nearly three polar orbits of the Sun from 1993 to 2008 (it is still functioning today, but at a reduced capacity). Although a weakening of the solar wind may not sound very important, the effects of this reduction will have serious implications, diminishing the natural defences of the heliopause (our Solar System’s invisible barrier) which protects us from high energy cosmic rays blasting through intergalactic space…

The heliosphere (NASA/Feimer)
The heliosphere (NASA/Feimer)

Ulysses has orbited the Sun four times longer than was originally planned. This tough solar satellite was launched in 1990 on board Space Shuttle Discovery, and in 1992, the probe used Jupiter to slingshot it out of the Solar System’s ecliptic to begin taking in situ measurements of solar wind speed and density at all latitudes from pole-to-pole. This is an unprecedented mission that continues to function today. However, Ulysses’ plutonium fuel in its radioisotope thermoelectric generator (RTG) is dwindling to the point where this landmark mission will die from old age over the coming months.

And yet, the geriatric spaceship still reveals characteristics about our Sun that we could never hope to observe confined to the ecliptic plane. So, in (possibly) one of Ulysses’ biggest discoveries to date, scientists have uncovered the strange phenomenon that the solar wind output has decreased to an all-time low (since accurate records began half a century ago), as the Ulysses Principal Investigator explains:

“The Sun’s 1.5 million km-per-hour solar wind inflates a protective bubble around the Solar System and can influence how things work here on Earth and even out at the boundary of our Solar System, where it meets the galaxy. Ulysses data indicate the solar wind’s global pressure is the lowest we have seen since the beginning of the space age.” – Dave McComas, Principal Investigator for the Ulysses solar wind instrument and senior Executive Director at the Southwest Research Institute in San Antonio, Texas.

This “protective bubble” is also known as the heliosphere, a huge volume of space in which all the planets, asteroids and comets are deep inside. It is the total extent of the Sun’s influence, pushing out into interstellar space, the limit of which is known as the heliopause. The heliopause is formed through a balance between the outward pressure of the solar wind and the inward pressure of the interstellar medium, should one of these pressures fluctuate, the heliopause will expand or contract. Should the solar wind pressure decrease, the heliopause will shrink under the greater interstellar medium pressures. This is exactly what Ulysses has detected: a reduction in solar wind pressure.

So what does this mean to us? The heliopause blocks and deflects the majority of damaging high energy interstellar particles (a.k.a. cosmic rays). Should the solar wind weaken, the heliopause will become a less-effective shield, letting more cosmic rays into the Solar System.

“Galactic cosmic rays carry with them radiation from other parts of our galaxy. With the solar wind at an all-time low, there is an excellent chance that the heliosphere will diminish in size and strength. If that occurs, more galactic cosmic rays will make it into the inner part of our Solar System.” – Ed Smith, NASA’s Ulysses Project Scientist from the Jet Propulsion Laboratory, California.

Artist impression of Ulysses (ESA)
Artist impression of Ulysses (ESA)

The effects of this happening will be far-reaching and could severely impact the future of manned exploration of the Solar System.

Solar physicists made this discovery when analysing Ulysses data from the probe’s third scan of the solar wind and interplanetary magnetic field (IMF) from the Sun’s north to south poles. On comparison with previous scans, it was found that the solar wind pressure and the radial component of the magnetic field embedded in the solar wind had decreased by 20%. The magnetic field strength surrounding Ulysses had dropped by a huge 36%.

So what could this be attributed to? Physicists simply do not know. Perhaps it might be related to the extended solar minimum in recent months, as Smith appears to suggest. “The sun cycles between periods of great activity and lesser activity,” Smith said. “Right now, we are in a period of minimal activity that has stretched on longer than anyone anticipated.”

Compelling results from a compelling solar mission…

Source: ESA

Posted on by Ian O'Neill

Really Bad News: LHC to be Switched Off Until Spring 2009

It looks like some significant repairs will need to be made to the LHC before a re-start attempt (CERN)

[/caption]First there was a glitch with one of the huge 30-tonne transformers causing a delay of a few days, then a quench leaked a tonne of helium coolant into one of the tunnels, forcing a two-month shutdown while repairs could be made.

Brace yourselves for some more bad news.

In a statement released by CERN today, due to an obligatory maintenance period, the LHC will have to remain off-line until late March or early April 2009. Problems with an experiment as huge as the worlds biggest particle accelerator can be expected, but this will be a costly delay and a psychological setback after the initial excitement of the first particle circulation on October 10th. The elusive Higgs Boson will have to wait a few more months…

I had a nagging feeling over the weekend after writing about the LHC quench and the two month delay in operations – what if the delay is longer than we think? The severe damage was caused by faulty wiring between two supercooled electromagnets when scientists carried out electrical tests at the facility Friday morning, resulting in a helium leak between sections 3-4 of the 27 km (17 mile) accelerator ring. Although no one was injured, the emergency services had to be called and the electromagnets heated up well beyond operational temperatures. Initial reports suggested experiments would be put back until the end of the year, but now it would seem the LHC won’t accelerate particles again until spring 2009.

“Coming immediately after the very successful start of LHC operation on 10 September, this is undoubtedly a psychological blow. Nevertheless, the success of the LHC’s first operation with beam is testimony to years of painstaking preparation and the skill of the teams involved in building and running CERN’s accelerator complex. I have no doubt that we will overcome this setback with the same degree of rigour and application.” – CERN Director General Robert Aymar.

This is indeed a severe blow to CERN and the scientists at the LHC, but the delay is necessary as the time required to warm up the accelerator, fix the problem and cool it down again will extend into CERN’s obligatory winter maintenance period. Therefore we won’t see any more accelerated protons until 2009.

Once again, in light of these setbacks, physicists are keeping positive and hoping for success in the near future. “The LHC is a very complex instrument, huge in scale and pushing technological limits in many areas,” said Peter Limon in the CERN press release, who was responsible for commissioning the Tevatron at Fermilab in the USA. “Events occur from time to time that temporarily stop operations, for shorter or longer periods, especially during the early phases.”

There have been delays in the commissioning of the LHC (after all, it was originally planned to be operational in the mid-2000s) and setbacks in the last few days, but after two decades of planning and construction, a few more months isn’t that long in the grand scheme of things…

Source: CERN press release

Posted on by Ian O'Neill

NASA Uses 90 Rubber Ducks to Study Global Warming

Little yellow ducks, the new face of fighing climate change (Wikimedia Commons)

[/caption]NASA scientists have dropped 90 yellow rubber ducks into holes in Greenland’s Jakobshavn glacier in an attempt to understand why glaciers speed up during summer months as they slip into the sea. The ducks, attached to a football-sized probe, have an email address and message prompting anyone who discovers the ducks to contact NASA to reveal where and when the duck was found. There is an undisclosed award for anyone who finds one of these rubber global warming crusaders. The NASA scientists, based at the Jet Propulsion Laboratory (JPL) in California, hope this campaign will shed new light on the melting mechanisms behind Greenland’s fastest moving glacier…

This story brings back memories of when 30,000 rubber ducks were washed off a cargo ship bound for the US from China back in 1992. Since then, these intrepid explorers have travelled on the world’s ocean currents, ending up as far afield as the middle of the Pacific to the coast of England. Although they have lost their yellow colouring after years of high seas and Sun damage, the duck-shaped pieces of plastic have provided scientists with a valuable insight into ocean circulation and are still found on beaches today. They have also become a commodity (changing hands for over £500 or $1000), been the focus of children’s story books and provided data for a computer model called the Ocean Surface Currents Simulation (used to help fisheries and find people lost at sea). So, in the footsteps of their forefathers, these new NASA rubber recruits hope to provide climatologists with information about the current global warming trend and impacts on polar ice.

Alberto Behar, one of the JPL scientists working with the army of rubber ducks explains, “Right now it’s not understood what causes the glaciers themselves to surge in the summer.” The rubber ducks will help to tackle this problem by carrying a probe with them so their progress can be tracked via GPS. The football sized probe will also relay information about the glacier’s innards as the rubber ducks flow with the ice into the sea.

So far, nobody has reported finding a duck or a probe, but Behar is hopeful that a fisherman or hunter might do in the near future. “We haven’t heard back but it may take some time until somebody actually finds it and decides to send us an e-mail that they have found it,” he said. “These are places that are quite remote so there aren’t people walking around.” Let’s hope the promise of a reward will be enough incentive for the finder to make contact with NASA (otherwise we might see them being advertised on eBay for £500 or $1000…).

The Jakobshavn Glacier is famous in its own right. The iceberg that sank the Titanic in 1912 is thought to originate from it and the glacier has a phenomenal ice discharge rate today, responsible for nearly 7% of the ice flowing from Greenland.

Sources: The Sydney Morning Herald, Times Online (from June 28th, 2007)

Posted on by Ian O'Neill

Solar Cycle 24 Sunspots Finally Say “Hello!”

Now you see them... The sunspot group as observed by SOHO MDI today (NASA/SOHO)

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After an extended period of calm for Solar Cycle 24, a cluster of sunspots have appeared on the disk of the Sun. Although we have observed sunspots since the beginning of this new solar cycle (which officially began on January 4th, 2008 with the observation of a high-latitude sunspot pair), this is the first time for many months “new” Cycle 24 sunspots have shown themselves. Before today, the sunspots (including occasional flares and coronal mass ejections) belonged to the previous cycle (Cycle 23). It would appear the spots have evolved into a cluster in a high-latitude location with the magnetic polarity consistent with this new cycle. But does this mean we can expect an increase in solar activity after this pretty dull period of “blank” solar disk observations? Your guess is as good as mine…

Overlapping solar cycles are natural occurrences, and extended solar minima are not unexpected, but many predictions of an extended period of solar calm have been put forward since Solar Cycle 24 appeared to shy away after the initial excitement in January. Although the Sun has been surprisingly quiet for several months, we’ve still had sporadic sunspot activity (plus the occasional flare and CME eruption), but none could be attributed to the new Cycle 24 (although I erroneously thought the August sunspot activity was due to Cycle 24, it was in fact due to the overlapping Cycle 23).

A closeup of the Cycle 24 spots. Observed on September 22nd at Selsey, West Sussex, UK (© Pete Lawrence)
A closeup of the Cycle 24 spots. Observed on September 22nd at Selsey, West Sussex, UK (© Pete Lawrence)

So how can we be so sure these new observations are of Cycle 24 spots and not Cycle 23 spots? After quickly glancing at the Solar and Heliospheric Observatory (SOHO) image (top), we can see a cluster of activity at a fairly high latitude. Generally speaking, one would expect sunspots at the beginning of a new cycle to appear at high latitudes. As the 11-year solar cycle progresses, sunspot activity will begin to drift equator-wards, to lower latitudes. “Old” Cycle 23 sunspots have generally appeared near the solar equator, so the sunspots observed today can be attributed to the “new” Cycle 24.

The clincher for identifying these spots as belonging to a new solar cycle is their magnetic polarity. Sunspots often appear in pairs of opposite polarity (i.e. one will be magnetic north, the other will be magnetic south), and this new cluster is consistent with the polarity expected for Cycle 24 sunspots. SOHO uses its Michelson Doppler Imager (MDI) Magnetogram instrument to observe magnetic polarity, and it would appear that the polarity of this sunspot cluster has an opposite magnetic north/south to previous Cycle 23 observations.

So does this mean we might see an increase in solar activity from here on in? Although this is an encouraging observation, the Sun could revert back to its “blank” state as quickly as it revealed these sunspots to SOHO. However, there is also a chance this could herald the beginning of accelerated solar activity, possibly still fulfilling NASA’s 2006 prediction that Solar Cycle 24 will be a “doozy.”

Watch this space…

Original source: Space Weather

Posted on by Ian O'Neill

Helium Leak Forces LHC Shutdown for at Least Two Months

A series of problems forced LHC shutdown (CERN/LHC)

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It’s this sort of news I really did not want to wake up to. At 0927 GMT Friday morning, a fault known as a “quench” resulted in the leakage of a tonne of helium coolant causing 100 of the LHC superconducting magnets to heat up 100°C. The fire services had to be called and it was some time before engineers could access the tunnels to assess the damage. It was worse than they were expecting. Although no one was hurt and there was no danger to the public, the once-supercooled magnets were one hundred times warmer than they should be and optimal vacuum conditions had been lost. To perform repairs, the rest of the damaged sector will need to be warmed up and then slowly cooled down again, resulting in a shutdown of LHC operations for at least two months…

The leak occurred between the Alice and CMS detectors (sectors 3-4) after repairs to the faulty 30-tonne transformer were being finalized and the systems were being powered up to begin a new series of commissioning tests. According to the LHC logbooks, temperatures rose by 100°C and the vacuum required within the equipment for particle circulation to be possible was lost. Engineers had to wait for oxygen levels to return to normal within the tunnels before they could investigate the “meltdown.”

Although last week’s fault with the transformer caused frustration, setting LHC experiments back by a few days, scientists were optimistic the incident would have minimal effect on the first scheduled particle collisions in October. Friday’s quench, however, is a serious incident, knocking the largest experiment mankind has ever attempted offline for at least two months. Although this is sad news, many scientists are keeping a positive attitude:

“This kind of incident was always a possibility with such a unique and demanding project, that’s why we were so tense on the 10th [of September]. Having seen those tantalising first signs of beam in our detectors, everyone is raring to go. So it’s really disappointing, and hard for us to keep in perspective right now. But a delay like this in a 20-year project isn’t an utter disaster and I’m sure the team at Cern will fix it, and make it more robust as they go.” – Prof Jonathan Butterworth of University College London, the UK head of the Atlas detector.

So what happened? The basic operating conditions for the LHC depend on very low temperatures and a very high vacuum state. It would appear both key conditions were lost as engineers tested the electrics of the LHC in the run-up to full commissioning. There was a faulty connection between two of the superconducting magnets, so when the system was switched on, the high current melted the connection, causing the helium leak. The loss of supercooled helium caused a rapid release of stored energy (an event known as a quench), heating the magnets and destabilizing the vacuum conditions.

After such a smooth start to the first proton circulation on September 10th, these setbacks may come as a surprise. However, probing the frontier of physics rarely happens without a few hiccups along the way, so let’s hope this incident will be the last and we can once again look forward to the first particle collisions toward the end of the year…

Sources: BBC, Telegraph

Posted on by Ian O'Neill

Transformer Glitch Halts LHC Operations

Debris from particles hitting the collimator blocks were detected in the calorimeters and muon chambers (CERN/LHC/CMS)

[/caption]According to reports, only a day after the first successful circulation of protons in the Large Hadron Collider (LHC) last week, operations at the world’s largest particle accelerator had to be stopped due to a fault with a 30 tonne transformer used to cool part of the facility. The protons were not being accelerated at the time and there was no risk to safety at the LHC.

Rather than maintaining the equipment below the operational 2 Kelvin, the transformer glitch caused temperatures to rise to over 4 Kelvin (which is still cold, after all it is only 4 degrees above absolute zero – but it’s not cold enough). The transformer failed after the successful anticlockwise circulation of protons on the evening of September 11th and rumours about LHC problems have only just been confirmed…

This was bound to be a frustrating problem for the LHC engineers, but in many respects it was inevitable. This is a facility more complex than any technology ever built; a 27 km ring of 1000 supercooled electromagnets, operating at a temperature colder than anything in the Universe, with 2000 separate power supplies and a vast number of synchronized detectors and sensors… it’s little wonder the LHC may experience one or two technical hitches.

“This is arguably the largest machine built by humankind, is incredibly complex, and involves components of varying ages and origins, so I’m not at all surprised to hear of some glitches. It’s a real challenge requiring incredible talent, brain power and coordination to get it running.” – Steve Giddings, physics professor at University of California, Santa Barbara

However, this fault was critical to LHC operations, ultimately shutting the experiment down until technicians find the problem. Judith Jackson, spokesman for the Fermi National Accelerator Laboratory, is not surprised the LHC should suffer the occasional setback. “We know how complex and extraordinary it is to start up one of these machines. No one’s built one of these before and in the process of starting it up there will inevitably be glitches,” she said.

Apparently, transformer malfunctions are commonplace in particle accelerators. “These things happen,” she said. “It’s a little setback and it sounds like they’ve dealt with it and are moving forward.”

According to CERN scientists, the proton beams made “several hundred orbits” clockwise and anticlockwise before the experiment had to shut down.

The Associated Press investigation into the September 11th transformer glitch indicates that the problem has been identified and CERN scientists are still on track for the first particle collisions in October.

Source: AP

Posted on by Ian O'Neill

“Eight Minutes of Terror”: Solar Physicists Find a Supersonic Way to See the Transition Region

A Black Brant sounding rocket of the type that will carry SUMI above Earth's atmosphere (NASA)

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Solar physicists will have the unprecedented opportunity to peer inside one of the most mysterious regions in the Sun’s atmosphere. Separating the chromosphere (at a temperature of a few thousand Kelvin) and the extended corona (at a temperature of over a million Kelvin) is a very thin layer about 5000 km above the photosphere (a.k.a. the Sun’s “surface”). The transition region dictates the characteristics of the hot plasma passing from the Sun into space and is right at the start of the solar-terrestrial chain, controlling space weather. We are unable to directly observe the transition region as it doesn’t radiate in wavelengths observable from the Earth’s surface, but it does emit UV radiation observable from space. So a group of solar researchers are packing some very sensitive instrumentation into a sounding rocket that will very briefly take some snapshots of the transition region. But they will have to be quick, from instrument deployment to re-entry, only eight minutes will be allowed to take the necessary UV spectroscopic observations…

To start us off, Jonathan Cirtain from the Marshall Space Flight Center explains this new mission in a nutshell:

“Early next year, we’re going to launch an experimental telescope that can measure vector magnetic fields in the transition region.” – Cirtain.

But why? Hasn’t the transition region been observed before? Actually, no. The surface of the Sun has been tirelessly studied, as has the solar atmosphere, but the thin layer separating the two has, so far, remained hidden from solar astronomers. “Just bad luck, really,” says Cirtain as he explains why the transition region has remained a mystery for so long. “Gas in the transition region doesn’t produce many strong spectral lines that we can see at visible wavelengths.” But it does radiate UV emission that can be observed from space, so Cirtain hopes his research group will be the first to peer right inside by pushing into space.

Coronal loops as viewed by the Transition Region and Coronal Explorer (TRACE)
Coronal loops as viewed by the Transition Region and Coronal Explorer (TRACE)

The transition region is critical to the understanding of the magnetic structure of the Sun and its corona. Below this thin layer, plasma pressure dominates, above it, magnetic pressure dominates. This means that above the transition region, the characteristics of the Sun’s magnetic field overwhelm the decreasing plasma pressure. The corona becomes a highly structured entity from the transition region and upward, which can be seen in the structure of magnetic coronal loops (pictured).

But what will they be measuring? How can the magnetic structure inside the transition region be seen? The instrument to be launched is called the Solar Ultraviolet Magnetograph Investigation (SUMI) and it is designed to measure the magnetic phenomenon of “Zeeman Splitting.” The Zeeman effect occurs when radiating plasma is in the presence of a strong magnetic field. So in the case of SUMI, the instrument will observe the UV emission from the transition region and detect the fine-scale splitting of the UV spectroscopic emission lines. The stronger the magnetic field, the greater the splitting.

SUMI can also measure the polarization of the split lines, so Cirtain’s team will have all the information they’ll ever need about the magnetic field in the transition region: both magnetic filed strength and direction. So far, so good.

But how is Cirtain planning on getting SUMI into space? To possibly make it cheap, and because SUMI is a comparatively simple instrument, it won’t need to be in space long. So the plan is to blast it into the lowest reaches of space on a sub-orbital flight inside the nose cone of a Black Brant sounding rocket. 68 seconds and 300 km (185 miles) into the flight, SUMI will be jettisoned. “We’ll be above more than 99.99% of Earth’s atmosphere. From that moment, we’ve only got 8 minutes to work with. We’ll target an active region and start taking data,” Cirtain added.

Carrying out short sounding rocket missions is not new to solar physics, some of the very first space-based observations of the Sun could only come from high altitude rockets. However, Cirtain will be nervous to see SUMI disappear into the stratosphere at 5,000 mph and has dubbed the flight the “Eight minutes of terror.”

So, from one of the simplest and cheapest observation campaigns, the mysterious transition region may start to give us some answers…

Source: NASA