Tag archives: astrophysics
The Magnus effect in action, destroying the world, an astrophysicist camps out in Manchester and more
By Hamish Johnston and Michael Banks
This week’s Red Folder opens with a fantastic video (above) from the folks at Veritasium. It involves dropping a spinning basketball from the top of a very tall dam in Tasmania and watching as the ball accelerates away from the face of the dam before bouncing across the surface of the water below. In comparison, a non-spinning ball simply falls straight down. This happens because of the Magnus effect, which has also been used to create flying machines and sail-free wind-powered boats. The effect also plays an important role in ball sports such as tennis and is explained in much more detail in our article “The physics of football”.
By Hamish Johnston
Recently I blogged about quark novae, which are a passion of the University of Calgary astrophysicist Rachid Ouyed. I caught up with Ouyed at the Canadian Association of Physicists Congress in Edmonton last month, where between sessions he was busy writing a paper about quark novae.
I managed to coax him away from his calculations for long enough to record the above video, in which he talks about quark novae – huge explosions that some astrophysicists believe could occur shortly after some supernovae. Ouyed also talks about the quark stars that may be left behind and how quark novae could affect how astronomers measure cosmological distances.
By Hamish Johnston at the CAP Congress in Edmonton, Canada
The first day of the Canadian Association of Physicists (CAP) Congress at the University of Edmonton closed yesterday on the theme of time travel. Surely that is science fiction, you are thinking? But Miguel Alcubierre of the National Autonomous University of Mexico (UNAM) wasn’t joking when he delivered the Herzberg Memorial Lecture yesterday evening (although he did giggle a lot during his talk, which was very endearing). The session was called “Faster than the speed of light” and it was a fascinating romp through some of the more bizarre implications of Einstein’s general theory of relativity (GR) – which is 100 years old this year.
By Matin Durrani at Sierra Negra, Mexico
Just as my Physics World colleague James Dacey mentioned earlier, neither of us felt super-wonderful yesterday visiting the Large Millimeter Telescope (LMT), which sits at a height of 4600 metres above sea level. Spectacular though the facility is, the air pressure is roughly 60% of that at sea level and there is so little oxygen that even walking up a flight of stairs made me feeling pretty light-headed.
So, James and I were both quite glad to descend with LMT director David H Hughes to a height of 4100 metres, where it was time to visit another leading Mexican astronomy facility – the High-Altitude Water Cherenkov (HAWC) gamma-ray observatory.
By James Dacey at Sierra Negra, Mexico
Friday was the final full day of the Physics World Mexican adventure and we ended with a breathtaking experience, quite literally.
Matin and I rose early in Puebla to travel over a hundred kilometres east to the ominously named Sierra Negra volcano. This extinct beast is home to two of Mexico’s finest astrophysics facilities.
By Matin Durrani
A couple of years back, I had the pleasure of travelling 1100 metres below ground to visit a dark-matter laboratory at the bottom of the Boulby Mine on the north-east coast of England. The journey was certainly memorable – it involved plunging down in a rattling lift cage for several minutes with a group of miners setting off on their morning shift. Once in the lab – housed inside a souped-up set of trailers – I interviewed physicist Sean Paling about the experimental projects going on there.
Setting up an underground lab, like that at Boulby, certainly doesn’t come cheap and in recent years, many have started to diversify into new areas. In the May issue of Physics World, which is now out in print and digital formats, Paling and his colleague Stephen Sadler – who is director at DURRIDGE UK Radon Instrumentation – describe the renaissance in the science taking place far beneath our feet. Studies in underground labs now range from Mars rovers to muon tomography and from radioactive dating to astrobiology.
By Tushna Commissariat
In recent years, science and science fiction have come together in cinema to produce a host of rather spectacular visual treats, the best of the lot being Christopher Nolan’s epic Oscar-nominated film Interstellar. That actual science has played a major role in film is pretty well known, thanks to the involvement of theoretical physicist Kip Thorne, who was an executive producer for the project. But in a near-cinematic plot twist, it has emerged that Thorne’s work on trying to develop the most accurate and realistic view of a supermassive black hole “Gargantua” has provided unprecedented insights into the immense gravitational-lensing effects that would emerge if we were to view such a stellar behemoth.
By Hamish Johnston
The big story this week is that astronomers working on the BICEP2 telescope may have spotted the first direct evidence for cosmic inflation. This is very good news for the physicist Andrei Linde, who along with Alan Guth and others did much of the early work on inflation. In the above YouTube video Linde, who is certainly in the running for a Nobel prize, receives a surprise visit from BICEP2 team member Chao-Lin Kuo. Kuo is the first to tell Linde and his wife, the physicist Renata Kallosh, the news that the theory that Linde developed more than 30 years earlier had finally been backed up by direct observational evidence. Not surprisingly, champagne glasses are clinking!
Here at physicsworld.com we have tried to tell both sides of the story: the thrill of seeing the first hints of cosmic inflation, tempered with calls for caution that more data are needed before inflation is victorious over other theories describing the early universe.
By Tushna Commissariat
It is always interesting to us at Physics World when a particular topic suddenly attracts the attentions of the physics community, especially when it’s a rather hotly debated subject. The past couple of days, for example, have seen a lot of talk about “sterile neutrinos”, based on two papers – published in quick succession on the arXiv preprint server – that suggest the tentative detection of these hypothetical paricles.
Both papers are based on an unidentified emission line seen in the X-ray spectrum of some galaxy clusters obtained by the European Space Agency’s XMM-Newton observatory. Intriguingly, sterile neutrinos are also considered to be possible dark-matter candidates, meaning that – if discovered – they would be the first fundamental particles to lie beyond the bounds of the Standard Model of particle physics.
By Tushna Commissariat
Inquisitive minds from all over the city of Bristol (where Physics World HQ is based) met at the University of Bristol’s Peel Lecture Theatre last night to hear astrophysicist Catherine Heymans give a talk entitled “The Dark Universe”, in which she tackled dark matter, dark energy, the structure of our universe from the largest to the smallest scales, flying pigs and even astronomical tooth fairies!
Heymans’ lecture was the first of a number of talks to celebrate the 25th anniversary of Physics World that we will be running with the Bristol Festival of Ideas, which hosts special events, talks and screenings held throughout the year in the city.
This being the first time that Physics World has been directly involved with the festival, we were pleased that Heymans’ talk was entirely sold out. And having a particular interest in astronomy, I made sure to attend the event, which proved to be a great success.