online.gif Environmental News Network
info-l.gif info-r.gif
view



Joe Blanton, director of our Research Correspondence staff, oversees the answering of 50,000 queries and comments addressed to the National Geographic Society annually. Each week he posts answers to three of the most interesting inquiries received online at Glad You Asked. Unfortunately, individual e-mail replies are impossible.

There’s big, and then there’s ...

Since the U.S.S.R. has broken up, is Canada now the largest country at 3,849,674 square miles (6,195,280 square kilometers)?

Canada’s a big place, no doubt about it. But the Russian Federation, or Russia, the entity that remained after the dissolution of the U.S.S.R., can lay claim to being the world’s largest country by area. Russia covers 6,592,800 square miles (10,608,500 square kilometers), more than 76 percent of the land area of the old Soviet Union.

That’s a whopping big country. It would make nearly two Canadas.

What happens to fish from which roe has been extracted to make caviar?

Well, they’re not invited to the party. Most caviar comes from sturgeon that prowl the waters of the world’s largest lake, the Caspian Sea. Once caught, the sturgeon are slit open and their masses of eggs—the roe—are removed to become one of world’s great delicacies. The de-roed, and quite dead, fish are then sold in markets. Sturgeon spawn but once and then die, a certain fate hastened only slightly by the caviar industry.

For years the Soviet Union and Iran controlled the pursuit of caviar in the Caspian Sea. Since the breakup of the Soviet Union, Russia and Iran vie with the newly independent nations of Kazakstan, Azerbaijan, and Turkmenistan for the caviar bounty. The resultant overfishing has lowered the sturgeon population dramatically. Many of the fish are caught before they have had a chance to spawn. With fewer fish to repopulate the sea, the future of caviar is uncertain.

What makes distant mountains look blue even when they’re green or brown up close?

Moisture and dust particles in the air scatter light waves, giving objects in the distance a bluish cast. Because light of short wavelengths—blue light—is scattered most, objects far away appear bluish. The same atmospheric conditions give faraway objects their blurred details and indistinct edges.

The famed Blue Ridge Range in the U.S. Appalachian Mountains draws its name from this phenomenon.