Phoenix's Finale, Magnetic Planetesimals, Diesel Fungus, Eagles and Otters, Sea Lion Diving, Fact or Fiction - Dogs and Chocolate


 

Download this episode.


Phoenix's Finale


phoenix.jpg Phoenix Lander, courtesy Corby Waste/JPL

The Phoenix spacecraft landed in May on a site near the Martian North Pole, in order to get a different picture of Mars than the one we've been getting from previous missions, which visited more equatorial regions. It has discovered ice, seen snow and dust storms, sampled the Martian soil and found interesting chemical compounds, suggestive that Mars might once have been a potential site for life. Using a Canadian instrument, it has even monitored the Martian weather. Now, however, the Martian winter is coming. According to Dr. Leslie Tamppari, project scientist on the Phoenix Mars mission at the Jet Propulsion Laboratory in Pasadena, California, the spacecraft will soon be freezing in the dark. Its solar power will be exhausted as the long polar night begins, and Phoenix will be frozen into the carbon dioxide ice cap that forms on Mars' North Pole every winter.


Listen to this:

Download Flash Player to view this content.


Related Links

Magnetic Planetesimals


planetisemals.jpg A young solar system with planetesmals - courtesy NASA

Like young rock stars, the earliest residents of our Solar System burned bright, died young and had magnetic personalities. Dr. Sabine Stanley, a Professor of Physics at the University of Toronto, has been studying rare angrite meteorites, remnants of planetesimals - tiny planets only 100 kilometers across - that formed well before Earth was around. These meteorites had powerful magnetic fields that could only have resulted if their parent planetesimals had a liquid metal core. In fact, Dr. Stanley says that even though these mini-planets were only a mere fraction the size of our planet, their molten cores produced magnetic fields that were anywhere between 20-40 percent that of the Earth.


Listen to this:

Download Flash Player to view this content.


Related Links

Diesel Fungus


strobel.jpg Dr. Strobel collecting in Patagonia

Dr Gary Strobel, a professor of Plant Sciences at the University of Montana in Bozeman, is a bio-prospector. He travels the world, looking for plants and fungi that produce interesting and potentially useful chemical compounds. In the past, he's found valuable antibiotics, but his most recent discovery was his most surprising. It's a fungus that eats plant material and produces from it volatile hydrocarbons that are very similar to diesel fuel. It could be tremendously valuable in developing ways to make green biofuels.


Listen to this:

Download Flash Player to view this content.


Related Links

Eagles and Otters


seaotter.jpg Sea Otter - courtesy USGS

The complex ecological web of the North Pacific has been undergoing some radical changes in the last decades, and scientists are only starting to untangle them. Dr. Jim Estes has followed one thread connecting animals as diverse as eagles and otters, which has re-emphasized the complexity and interconnections of these ecosystems. He's found that an as-yet unexplained shift in killer whale diets to hunting sea otters has caused the otter population to decline up to 99% in the Aleutian archipelago. This has caused sea-urchin populations to grow unchecked, and they've devastated the kelp beds. This has meant that eagles, who eat fish from the kelp beds (and baby sea-otters) are now hunting seabirds. Dr Estes is a Professor of Ecology and Evolutionary Biology at the University of California at Santa Cruz.


Listen to this:

Download Flash Player to view this content.


Related Links

Sea Lion Diving


sealion.jpg Sea Lion with research harness - courtesy MMRC

Another species experiencing mysterious major declines in the North Pacific is the Steller sea lion. Dr. Andrew Trites, the Director of the Marine Mammal Research Unit at the University of British Columbia, and his group, have been studying the sea lion's metabolism and diving, to try to understand if changes in climate or diet might help explain why the animals are in difficulty. Using a unique experimental setup in deepwater fjords, and trained sea lions, they've made some interesting and counterintuitive discoveries about how hard the animals have to work in their deepwater search for food.


Listen to this:

Download Flash Player to view this content.


Related Links

Fact or Fiction - Dogs and Chocolate


From time to time, we present a commonly held idea or popular saying - and ask a Canadian scientist to set us straight on whether we should believe it or not. Here's today's statement, from Shannon Regan in Markham, Ontario: Chocolate is poisonous for dogs. For the thumbs up or thumbs down, we go to Dr. Alexa Bersenas, a veterinarian with the Ontario Veterinary College in Guelph, who specializes in emergency and critical care for small animals. She confirms that it is science fact.


Listen to this:

Download Flash Player to view this content.



Theme music bed copyright RaphaÎl Gluckstein.
Creative Commons License by-nc-nd-2.0