U of A researchers have figured out why Earth sometimes has three electromagnetic doughnuts around it instead of two – research that could help us stop blackouts caused by solar flares.
University of Alberta physics professor Ian Mann and his team published a paper this week in Nature Physics on how giant electromagnetic waves from the Sun can cause Earth to get a third Van Allen belt.
This research builds on the THEMIS space weather experiment of 2007 to which the late St. Albert physicist John Samson contributed, Mann said. NASA launched a pair of probes in 2012 as a follow-up to that 2007 experiment to study the Van Allen belts.
“The Van Allen belts are essentially doughnut-shaped rings of very energetic particles that are trapped in the dipole magnetic field of the Earth,” Mann said, and are generally thousands of kilometres above its surface.
For reasons not fully understood, the electrons and ions in these belts zip around at nearly the speed of light, giving them tremendous energy. That’s a problem, since these belts are in the same spots where we like to put satellites, and they carry more than enough energy to zap them. Researchers want to understand what creates these belts and how they move around in order to protect satellites.
The 2012 probes introduced another twist to this mystery: they detected not two Van Allen belts, but three. What’s more, the third one vanished after four weeks. Mathematical models of the belts were initially unable to explain why this happened.
Turns out scientists weren’t thinking big enough, Mann explained. He and his team determined that a truly enormous magnetic wave caused by a flare or explosion on the Sun – a “space tsunami” far bigger than any they had ever imagined – would cleave the outer Van Allen belt in two, creating a third one. Subsequent waves then destroy the third belt and bring Earth back to two. Once they plugged these huge waves into their models, they reproduced the third belt.
These belt-splitting waves produce spectacular auroras in the sky and can potentially knock out power grids, as happened in Quebec in 1989, Mann said. By studying these storms, Mann and his team hope to forecast space weather and safeguard electrical systems and satellites.
Got a shirt that stinks? A U of A scientist might want it for research.
U of A human ecology professor Rachel McQueen put out a call this week for smelly shirts – specifically, for shirts that still stink even after they’re laundered.
“The problem of odour in clothing is certainly something a lot of people experience,” she said. Stink is a social and an environmental issue, as lingering smells can cause people to toss otherwise useable clothes.
While McQueen’s team has previously done trials on smell in clothes, those involved test articles that were typically worn less than 25 times per experiment. She’s looking for well-used clothes to study long-term stink.
Smelly clothes are caused by by-products left in fabric by sweat-eating bacteria, McQueen said. Little public research has been done on why smells persist after washing. Her team plans to study the density and structure of smelly clothes to determine which fabrics hold onto odours the longest.
McQueen said her team was specifically looking for tops with underarm odour – no underpants. The tops don’t have to be ridiculously smelly, as the team won’t actually be smelling them, and they don’t have to stink all the time – she also wants ones that start to reek only after you wear them again. Any top you contribute should be laundered and should be one you don’t expect to get back, as it will be shredded during the experiments.
McQueen said her team had received about six garments so far and hoped to get at least 100 by the end of the year.
People who used to have a smelly garment but got rid of it can send in details about it through a survey at textile.ualberta.ca/studies.
Malodorous vestments can be dropped off in the main foyer of the Human Ecology Building, located at 116th Street and 89th Avenue, Monday to Friday between 7 a.m. and 6 p.m.
