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Science News

UAlberta physicists have found never-before-documented evidence of strong winds around black holes during bright outbursts, when a black hole rapidly consumes mass.

NASA-SWIFT-A. SIMONNET, SONOMA STATE UNIVERSITY

Physicists find strong winds around black holes

The winds blow away a large portion of what the black hole would otherwise consume, explains lead author and PhD student Bailey Tetarenko. “In one of our models, the winds removed 80 per cent of the black hole’s potential meal.” The study also sheds light on how mass can transfer to black holes and how black holes can affect the environment around them. Using data from three international space agencies, the scientists used new statistical techniques to study outbursts from stellar-mass black hole X-ray binary systems. Their results show evidence of consistent and strong winds surrounding black holes throughout outbursts. Until now, strong winds had only been seen in limited parts of these events. Depending on their size, stellar-mass black holes have the capacity to consume everything within a three- to 150-kilometre radius. “Not even light can escape from this close to a black hole,” explained Gregory Sivakoff, associate professor of physics and co-author. Sivakoff was named the inaugural science fellow at TELUS World of Science Edmonton in March 2018. So, what exactly causes these winds in space? For now, it remains a mystery—though magnetic fields may play a role. The international study involved researchers from across Canada, Europe, and Japan, and data collected over the past 20 years from five international X-ray observatories. The paper was published in Nature, one of the world’s top peer-reviewed scientific publications.

10-year-old helps paleontologists discover ancient fish species

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SPRING/SUMMER 2018

Right: This never-before-seen fish is the first found in tropical South America from the Cretaceous period.

“It’s rare to find such a complete fossil of a fish from this moment in the Cretaceous period. Deepwater fish are difficult to recover, as well as those from environments with fast-flowing waters,” said Vernygora. “But what surprises me the most is that, after two years of being on a walkway, it was still intact. It’s amazing.”

PHOTO SUPPLIED

The fossil, Candelarhynchus padillai, is about 90 million years old and has no modern relatives, explained Oksana Vernygora, a PhD student and lead author on the study. In fact, the specimen is the first from the Cretaceous period ever found in Colombia and tropical South America. “A kid was walking into the Monastery of La Candelaria during a tour when he

noticed the shape of a fish in a flagstone on the ground,” explained Javier Luque, a PhD candidate and co-author. “He took a photo and showed it to staff at the Centro de Investigaciones Paleontológicas, a local museum we collaborate with to protect and study fossil findings from the region.” The museum then contacted Alison Murray, professor of biological sciences and Vernygora’s supervisor, who joined her colleagues in Colombia to retrace the steps of the 10-year-old tourist. What they found was a nearly perfect, completely intact fossil of an ancient fish in the flagstone walkway.

OKSANA VERNYGORA

Paleontologists from the University of Alberta have discovered a neverbefore-seen species of fish in Colombia, with help from a young and curious tourist.

Profile for University of Alberta Faculty of Science

Science Contours Spring/Summer 2018  

Science Contours is a semi-annual publication dedicated to highlighting the collective achievements of the Faculty of Science community. It...

Science Contours Spring/Summer 2018  

Science Contours is a semi-annual publication dedicated to highlighting the collective achievements of the Faculty of Science community. It...