Super-sized Supernova, Bee Beetles, Canada's Gravity Gap, Aping Conversation, Spider Venom Side Effect, Question of the Week: Electrical Plugs

 

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Super-sized Supernova

sn2006gy_main_330.jpg Artist's illustration of supernova SN 2006gy - Courtesy, NASA/CXC/M.Weiss

When scientists first noticed Supernova SN 2006gy last September, it looked just like your everyday stellar explosion. But as they made more and more observations, scientists realized they were seeing something special - a super-sized supernova. Earlier this week, a team of astronomers led by Dr. Nathan Smith of the University of California, Berkeley, announced that Supernova SN 2006gy was actually the biggest supernova anyone had ever seen. The explosion was so big, it could only have come from a new type of supernova called a pair-instability supernova, which only the most massive stars can produce. While these very massive stars are rare now, they were quite common in the early universe, meaning this new type of supernova might shed some light on how the universe evolved.

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Bee Beetles

bee_beetle.jpg Beetle larvae infesting a beehive - Courtesy, USDA

Honeybees and beekeepers in North America have been having a rough time of it recently. In the last several years commercial beehives have been failing at an unprecedented rate. Something, or some combination of things, has been stressing the bees to the point that they just abandon their hives and disappear into the countryside, never to be seen again. Dr. Peter Teal is the Research Leader of the Chemistry Research Unit at the Center for Medical, Agricultural and Veterinary Entomology of the US Department of Agriculture in Gainesville, Florida. He's been studying one possible contributor to the bees' tribulations: a new bee pest that has invaded North America and quickly spread among commercially raised bees. The pest is a tiny beetle that literally smells the bees' fear, and uses that smell to locate and invade beehives.

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Canada's Gravity Gap

gravity.jpg Illustration, Science/ M Tamisiea

Compared to our American counterparts, the Canadian ego has always been a bit fragile. So it can't be good news when we find out that Canada has less gravity than our neighbours to the south. But the joke is really on them, since less gravity actually means we weigh less. At first, scientists thought this gap in gravity was from the ancient ice sheets that compressed our country during the last Ice Age. But Dr. Jerry Mitrovica, a professor in geophysics at the University of Toronto, wasn't completely convinced. Armed with the most detailed gravity measurements of our country yet, he's determined that Canada is being sucked down into the centre of the Earth by plate tectonics. While the gravity gap from the former ice sheets will disappear in a few thousand years, the plate tectonics will still keep Canada's weight down for a long time afterwards.

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Aping Conversation

chimpreach.jpg Chimp reaching - Courtesy, Dr. F. DeWaal, Yerkes Primate Research Center

The origins of human language are, unfortunately, lost to the mists of time. But we do have relatives who can give us clues about how humans might have learnt complex communication. The best of these relatives are the chimps and bonobos. When Dr. Amy Pollick, a former researcher at The Yerkes Primate Research Center, decided to examine these two species for communication skills, she discovered something curious. When these great apes want to share information they use hand gestures, vocalizations and facial gestures. But of these three, only the hand gestures can carry multiple meanings. A scream always means one thing, but an outstretched hand can change meaning depending on the context. Dr. Pollick thinks this means gesturing could have preceded speech as a means of passing messages in early hominins.

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Spider Venom Side Effect

brazilspider.jpg Brazilian Wandering Spider - Courtesy, Parana State Govt., Brazil

The Brazilian Wandering Spider (Phoneutria nigriventer) is a poisonous spider that's often found in the banana trees of South America. The spider's bite is toxic, and leads to pain and raised blood pressure. But beyond these, fairly standard effects, there's one side effect of the bite that's attracted the attention of Dr. Romulo Leite, a research scientist at the Medical College of Georgia. Men bitten by this spider often develop erections that can last for more than an hour. Dr. Leite has isolated the compound responsible for the tumescence, and is currently testing to see if it can be used to develop new treatments for erectile dysfunction.

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Question of the Week: Electrical Plugs

This week's question comes from Bernadette Harris, from somewhere in cyberspace, who asks: What has changed with our electricity in recent years? Why are electrical plugs now polarized, so that one prong is bigger, and the plug can only go into the socket one way?

For the answer, we plugged into Dr. Peter Lehn, a professor of electrical engineering at the University of Toronto.

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