A few noteworthy news items from the week:
• Shift in Magnetic North Pole Causes Tampa Airport to Close Runway. As we've noted before, the magnetic North Pole—the spot toward which compasses point—moves. Compass needles in Africa have been shifting by about one degree per decade over the last century. Magnetic north is currently (I'm eyeballing this from a map) in the Arctic Ocean north of Canada's Yukon Territories, moving about 40 miles a year toward Russia. This has caused the Tampa airport to close its main runway to update the navigational information painted on the runway. The bigger question: Why only Tampa?
How the magnetic North Pole has moved over the last century.
• More Mass Bird Die-offs. On top of the 5,000 red-winged blackbirds that died and fell from the sky in Arkansas on New Year's Eve, hundreds of birds (a variety of species) have been found dead in Louisiana and hundreds (maybe thousands) of turtle doves have been found dead in Italy. As I mentioned on Facebook earlier this week, one theory for the Arkansas bird deaths is that fireworks scared and disoriented the birds, which have extremely high blood pressure and heart rates and can be vulnerable to fright. Interestingly, another theory is that the deaths are linked to shifts in the Earth's magnetic field, which birds are able to sense because they have a crystal of magnetite in their heads (part of their navigational system). It should be mentioned that mass bird deaths aren't so rare during migrations...but it's not migration season.
What caused so many red-winged blackbirds to die?
• Girl Discovers Supernova. Ten-year-old Kathryn Gray, the daughter of an amateur astronomer from the Canadian province of New Brunswick (Maine's next-door neighbor), became the youngest person ever to discover one of the bright, huge exploding stars. She found it in a galaxy 240 million light years away, meaning the explosion happened that long ago and the light is just now reaching us. Over billions of years supernovas have created many of the elements in the universe, including those found in the Earth (hence the molten iron-and-nickel outer core that creates the magnetic field) and even those in our bodies. As an astronomy-savvy young boy declared to me at The Naturalist's Notebook two summers ago, "We're all made of exploded stars!"
• Record Price for Vanishing Bluefin Tuna. We devoted an entire wall at the Notebook this year to the problem of overfishing. It has depleted the world's large-fish population by 90 percent. One of the most notable species threatened by human appetite is the bluefin tuna, a prize catch for sushi and sashimi eaters. Thus this week's celebratory headline "Bluefin Tuna Gets Record Price ($396,000) at Japanese Auction" was no reason for celebration. The price for bluefin tuna keeps rising because demand is growing and the fish are harder to find. If you want to learn more about the bluefin tuna, do a search for oceanographer and writer Carl Safina, who has been a leader in the fight to protect the fish.
Bluefin tuna
Today's Birthday:
English physicist, cosmologist and author Stephen Hawking turns 69. A quote from him: "When one's expectations are reduced to zero, one really appreciates everything one does have."