By Tushna Commissariat
It’s not often that we come across a mention of an astronomical event measured in Earth years, let alone months or hours. So suffice to say I was pretty surprised by a recent XMM-Newton finding that talked about a star orbiting a black hole at the furious rate of once every 2.4 hours! Further investigation revealed that this has only broken the previous record by an hour, but these extremely short orbits still have me rather amazed. Certain short orbital period binary stars or pulsars do have even shorter periods of less than an hour, but this star orbits a stellar-mass black hole (it’s about three times more massive than the Sun) that is roughly a million kilometres away from it. The video below, courtesy of the European Space Agency (ESA), is an animation showing one complete orbit of the star.
By Tushna Commissariat
This week marks 50 years since astronomer Maarten Schmidt’s discovery of the quasar, using the giant Palomar Observatory telescope. Quasars or quasi-stellar objects are a kind of active galactic nucleus that astronomers believe are powered by supermassive black holes and are scattered throughout the universe. They have always fascinated me, being some of the brightest, most distant and highly red-shifted astronomical objects in our universe. Over the years, thousands of quasars have been identified and they have dramatically influenced our ideas about the scale of the observable universe and have helped astronomers shed some light on the early universe.
In fact, just this week an international team of researchers announced the discovery of an extremely rare triple quasar system – only the second one observed to date. These systems are considered to be extremely rare and are difficult to spot. By combining multiple telescope observations and advanced modelling, the team – led by Emanuele Farina of the University of Insubria in Como, Italy – was able to discover the triplet quasar, called QQQ J1519+0627. The researchers say that light from the quasars has travelled nine billion light-years to reach us, meaning that it was emitted when the universe was only a third of its current age. Advanced analysis confirmed that what the team found was indeed three distinct sources of quasar energy and that the phenomenon is extremely rare.
So in light of these exciting findings, in this week’s Facebook poll we are asking you to pick your favourite astronomical objects.
By Tushna Commissariat
There’s nothing quite like mentioning extraterrestrials or aliens to get us “Earthlings” all excited or riled up! Late last week, a paper popped up on arXiv, by astronomer Alan Penny from the University of St Andrews. He outlines an incident where, for a short while, the possibility of alien contact was seriously considered. He was talking about what was ultimately the discovery of the first pulsar; but at the time the researchers couldn’t help but wonder if they had come across the first “artificial signal” from outer space.
The exciting happenings began in August 1967, when Jocelyn Bell Burnell (then a graduate student working with Antony Hewish – controversially, only Hewish won the Nobel prize for the pulsar discovery in 1974) at the University of Cambridge, noticed a particular source that had a “flickering pattern” that, over a few weeks, she realized showed up regularly each day at the same sidereal time. That December Bell pinpointed the specific position of the source in the sky using another telescope and the discovery was confirmed. In the coming months, three more similar patterns were found and the researchers agreed on “pulsating stars” or pulsars being the source. But during those winter months, the possibility that they had encountered the first alien signal loomed large. In fact, Brunell and colleagues dubbed the first pulsar LGM-1 or “Little Green Men”; although it was changed to CP 1919, and is now known as PSR B1919+21.
By Tushna Commissariat
After the rather disappointing news for SUSY researchers from the Hadron Collider Conference in Kyoto this week, it seems as if physicists at the conference have not had anything exciting to say about the Higgs boson either. While both the CMS and ATLAS collaborations did present their latest results, from data collected since the historic Higgs discovery in July, all the current results still point to a Standard Model Higgs.
As a number of other bloggers have already pointed out, what is probably most interesting about these latest results is what is missing – both CMS and ATLAS have only updated certain channels. Conspicuous by its absence was the diphoton (gamma–gamma) channel, which was not updated by either collaboration. The reason for this seems to be some discrepancy between the analysis done by the two experiments, with concerns regarding systematic errors and calibration. Adam Falkowski, who writes the Resonances blog, explains these discrepancies in some more depth.
Papers with the new results from both CMS and ATLAS are available, but the usual blog suspects – Peter Woit, Matt Strassler and the viXra – all agree that the results are anti-climactic. It seems as though we will have to wait until the mysterious diphoton channel gives up its secrets, hopefully by sometime next year, before there is Higgs euphoria again.
By Tushna Commissariat
Earlier this week, the UK’s Royal Mail issued a set of six special stamps to celebrate the 50th anniversary of Britain’s first satellite – Ariel 1 – that was launched on 26 April 1962. While the Royal Mail has issued stamps with space images on them in the past, the new set “takes the theme forward, exploring the solar system in greater depth than ever before”, according to the company.
All six images are taken from missions conducted by the European Space Agency (ESA) and include the cavernous craters of Mars, the dizzying rings of Saturn, a close-up image of the Sun and a filament, a green-tinged picture of Titan – Saturn’s largest moon, the Lutetia asteroid and a shimmery picture of the south pole of Venus. Andrew Hammond, the Royal Mail stamps spokesperson, said “Britain has played an important role in space exploration over the last half a century and our Space Science issue is a fitting tribute.”
You can buy the set at the Royal Mail website.
Artist’s impression of 55 Cancri e – graphite surrounding diamond, then silicon and a molten iron core. (Courtesy: Haven Giguere, Yale University)
By Tushna Commissariat
There’s nothing quite like a planet made mostly of diamond to get everybody’s attention, and that is what a team of astronomers from Yale says it might have found. The researchers say that 55 Cancri e, a rocky super-Earth, is mainly made of carbon – in the form of diamond and graphite.
This is not the first time a “diamond planet” has hit the headlines. Last year an international team of researchers found a pulsar, with an orbiting planet about the mass of Jupiter, that seemed to be made entirely of diamond. Further research revealed that “the planet” was, in fact, the pulsar’s companion star – an ultralow-mass carbon white dwarf that just about survived being completely destroyed by the pulsar. The core of the remnant would mostly be carbon and some oxygen, but thanks to the near-Jupiter mass of the companion star, its own gravity could crystallize it to form diamond – just how carbon is transformed into diamond deep within the Earth. You can take a look at the paper about that research here.
This time, astronomers seem much more certain that what they are dealing with is indeed a planet. 55 Cancri e belongs to the 55 Cancri star system, which is a mere hop, skip and jump away from Earth in astronomical terms at a distance of 41 light-years. Indeed, the system – with five known planets that orbit a parent star – can be seen with the naked eye on a clear, dark night. Interestingly, 55 Cancri e is the closest planet to its parent star, with a dizzying 18-hour orbit – the shortest orbit known for an exoplanet – and is tidally locked, so one side always faces the star. Until now, it was thought to have a substantial amount of super-heated water on its surface and was believed to have a similar chemical composition to Earth.
However, new data and research have shown that the planet contains no water at all, and appears to be composed primarily of carbon, iron, silicon carbide and, possibly, some silicates. The study, led by Yale postdoctoral researcher Nikku Madhusudhan and colleagues, estimates that at least a third of the planet’s mass – the equivalent of about three Earth masses – could be diamond.
“This is our first glimpse of a rocky world with a fundamentally different chemistry from Earth,” says Madhusudhan. “The surface of this planet is likely covered in graphite and diamond rather than water and granite.” In 2011 Madhusudhan revealed the first discovery of a carbon-rich atmosphere in a distant gas-giant planet, opening the possibility of long-theorized carbon-rich rocky planets or “diamond planets”.
The conformation of this carbon-rich super-Earth now means that the many rocky exoplanets thought to exist can no longer be assumed to have chemical constituents, interiors, atmospheres or biologies similar to those of Earth, according to Madhusudhan. A carbon-rich composition could influence the planet’s thermal evolution and plate tectonics, for example, with implications for volcanism, seismic activity and mountain formation.
This is the first time astronomers have identified a likely diamond planet around a Sun-like star and specified its chemical make-up. Further spectroscopic analysis of the planet’s atmosphere and its parent star’s composition will be necessary to ascertain 55 Cancri e’s “priceless” composition.
A paper on the work has been accepted for publication in the journal Astrophysical Journal Letters and an arXiv preprint is available here.
IOP president, Sir Peter Knight. (Courtesy: IOP/Mark Earthy)
By Tushna Commissariat
Yesterday, I was in London attending the annual awards dinner of the Institute of Physics (IOP), which publishes Physics World, as well as the first ever IOP Innovation Awards, held earlier in the afternoon. It proved to be an exciting and jam-packed day to say in the least.
The IOP Innovation Awards have been set up to recognize and celebrate businesses from the UK and Ireland that have achieved significant commercial success by finding a niche in the market and developing physics-based applications to fill it. This year, the four inaugural awards went to a wide range of products.
All afternoon long, the Innovation Awards room was full to the brim with scientists, developers, students and recruiters keen on finding out what the companies did and the products they had to offer. In fact, the room was so busy that IOP president, Sir Peter Kinght, who came along to address the ceremony, found it hard to make his way to each event desk and promised a larger space for next year’s meet. He was keen to show the world the “vibrancy of investment in the technology” the various companies had developed. “Physics is not just about cosmology or particle physics – that’s great too – but it’s about making a difference in the world,” he told visitors. Knight finished by promising that next year, the Innovation Awards would be “bigger and better”.
Visitors at the Innovation Awards. (Courtesy: IOP/Mark Earthy)
One winner was a small, noiseless, high-volume pump that has many applications in medical devices, developed by Technology Partnership, based at the Melbourn Science Park in Hertfordshire. The tiny pump runs at 20 kHz and is already being used for wound therapy devices and in an electronic atomizer that is used for more efficient drug delivery. The device has only been on the market for 18 months, but has already earned the company more than £1m in additional revenue.
Another award went to Canterbury-based Naneum, which has developed a portable and easy-to-operate particle monitor to detect and identify nanoparticles pollutants, with applications in environmental monitoring, occupational health and atmospheric physics. The company was keen to develop a device that was easy to transport and could be used by any engineer, rather than someone trained to specifically do so. The device – the Nano-ID NPS 500 – is forecast to earn the company more than £1.5m over the next two years.
“Personal confocal” is how the next award winner, Aurox, describes its microscope attachment that lets researchers take 3D high-resolution images without the costs of investing in a confocal laser scanning microscope. Spun out from the University of Oxford, the firm has now partnered with Andor and Carl Zeiss to develop the Viva Tome imaging system. Having developed the new technology three years ago, it has already earned the company almost £1m in additional revenue. Aurox also won a Queen’s Award for Enterprise in Innovation earlier this year.
Some of ZBD’s e-paper supermarket labelling. (Courtesy: Physics World/Tushna Commissariat)
The final company to be lauded was ZBD Solutions, which has spent the past 12 years perfecting a novel e-paper display that makes shelf-edge labelling easier. The Malvern-based company was spun out from the liquid-crystal research centre at DERA, formerly the UK Ministry of Defence’s research arm. The current avatar of their e-paper (pictured above) was developed four years ago and has created 62 jobs and earned the company an additional £20m. ZBD Solutions was ranked 5th on this year’s Sunday Times Hiscox Tech Track 100 league table.
The IOP Awards dinner took place later in the evening and 600 of the “who’s who” of the UK physics community were out in their finest clothes. IOP medals span the entire spectrum of physics research, physics education and outreach as well as the application of physics and physics-based technologies. They are given to “identify and honour physicists who are today making remarkable contributions and to encourage younger members of our community to greater success in the future”. A complete list of all the many awards and their winners of the 2012 medals can be found here.
In Knight’s address to the gathering he highlighted, among other issues, the lack of girls in physics, after it was noted that only 20% of girls have been taking physics A-levels over the past 20 years. His comments were made in the light of a new report published by the Institute on the same day entitled It’s Different for Girls. The report looks at changing the attitude of school teachers in all subjects, as well as parents, to encourage girls to take up A-level physics.
Professor Brian Cox, who was awarded the President’s Medal 2012 for his “achievements in promoting science to the general public and inspiring the next generation of physicists”, was the guest speaker at the dinner. In his witty and engaging speech, a video of which you can watch below, he addressed the excitement of the Higgs discovery made earlier this year as well as the sophistication of the Large Hadron Collider. But he also had some strong words to say about promoting bad science and how it was not acceptable – he highlighted homeopathy and some ill-advised comments made by Jeremy Hunt, the current health secretary, on the issue.
To much laughter, Cox followed that up with some amusing comments about “faith-based aviation” or the serious lack thereof by saying, “There is a reason why we don’t have…homeopathic aircraft that run on the memory of petrol.” He also spoke of how it was important for the government to invest in increasing the number of STEM graduates in the UK. He ended his address by thanking the physics community, saying “Without you, I would have nothing to say the next time I stand on a mountain!”
All in all, it was an entertaining and illuminating evening for the people in the UK who are involved in physics…and the raspberry and chilli ice-cream for desert was excellent too!
A gypsy moth caterpillar. (CC-BY-SA-3.0 Materialscientist)
Humans have a long and fruitful history of looking towards nature for ideas to build new technologies or solve problems. From Leonardo Da Vinci studying the flight of birds to develop the earliest “flying machines”, to the Swiss engineer George de Mestral developing Velcro after studying the surface of burrs, nature has long been influencing technologies.
A recent review paper published in the journal Smart Materials and Structures takes an in-depth look at the different “hairy” sensors that a whole host of animals possess. This could help us to develop our own sensors to serve a multitude of purposes from gauging flow turbulence to more efficient liquid-dispensing methods to developing robots that can successfully navigate underwater or underground and other biomedical applications. Such sensors would require many capabilities such as short response times and low detection thresholds – capabilities that already exist in animals.
Many life-forms live in conditions that are constantly changing and so have adapted a wide range of sensory strategies to survive. In the paper, the authors point towards many examples. Mexican blind fish rely on a” lateral line system” to detect movement and vibration in the surrounding water. Crickets use their hairy “cerci” or feelers that provide them with flow information that let them know if another creature is approaching them. Caterpillars also use cerci to detect airborne disturbances that let them know when predators, like flying wasps, are overhead. Meanwhile, bats control their flight by monitoring air-flow conditions via hairs on their wings.
According to the paper, “Among the various flow sensors in nature, the instinctive flow sensors of aquatics and arthropods are the most intensively studied.” In the initial sections the researchers look at the “morphology, function and biomechanics of the lateral line neuromas of aquatics and the fusiform hairs of arthropods are examined to shed light on the development of their artificial counterparts”. In later sections they divide the types of sensors that can be developed into six categories: thermal, piezoresistive, capacitive, magnetic, piezoelectric and optical sensors. They look at various groups around the world that are currently developing some of the different types of sensors considered and the different methods they use. The final discussion looks at how to best optimize such sensors, process the information they would provide and how the field will progress in the future.
So for an insightful look into all sensors hairy, take a look at the paper here.
Protons collide with lead nuclei, sending a shower of particles through the LHC’s detectors. (Courtesy: ALICE/CERN)
By Tushna Commissariat
In the early hours of this morning the Large Hadron Collider (LHC) successfully collided protons and lead ions for the first time, with the collisions being recorded by all of the detectors: ATLAS, CMS, ALICE and LHCb.
Late last year the LHC trialled a similar run, during which it accelerated separate beams of lead ions and protons. However, at that time the beams were not successfully collided, and the run was postponed. To learn more about the 2011 run, take a look at this news story.
The whole business of colliding different particles is a difficult one, as it presents physicists with a number of technical challenges. “Firstly, the collisions are asymmetric in energy, which is a challenge for the experiments,” explains accelerator physicist and lead-ion team leader John Jowett. “At the accelerator level we don’t really see the difference in particle size, but the difference in the beam size and the fact that the beam sizes change at different rates may affect how the particles behave in collisions.”
Also, the LHC normally accelerates two opposing proton beams from 0.45 to 4 TeV, before they collide at a total energy of 8 TeV. Radio-frequency (RF) cavities are used to give the beams the necessary energy boost, as well as to keep them in strict synchrony. But here is where another problem arises: the system ties the momentum of one beam to the momentum of the other, while it needs to account for the differences between the protons and the much heavier lead ions. A lead nucleus, containing 82 protons, is accelerated from 36.9 to 328 TeV, or from 0.18 to 1.58 TeV per proton or neutron, which means that the RF cavities need to be tuned to different frequencies for each beam. This allows both beams to achieve stable orbits within their own ring during injection and acceleration. In the past, other projects have experienced difficulties in getting this just right, as have researchers at the LHC.
“The RF systems of the two rings can be locked together only at top energy before collisions, when the small speed difference that still remains can be absorbed by shifts of the orbits that are acceptably small,” says Jowett. He further explains that the beams then have to be adjusted again by the RF system so that the collisions take place inside detectors, where experiments take physics data, so a lot of preparation has been needed to allow the LHC systems to carry out this new operational cycle.
Researchers are hopeful that this latest short run will deliver the first data for proton–nucleus collisions before a scheduled main run takes place from January to February 2013, just before the accelerator is shut down for maintenance.