Discover, September 30, 1992

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Artur Ekert can feel secure. If his friends are within 200 yards of him, he can send messages to them in an unbreakable code. It’s not that his signals are immune to wiretapping; snoopers can listen in. It’s not that his code is too complex for anyone to crack; it’s actually fairly simple. Ekert’s secrets are guaranteed by the basic laws of energy and matter. They forbid anyone from cracking his code, ever. That includes the army, the CIA, and, assuming that laws of physics are really laws, even God.

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Discover, September 1, 1992

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Transport yourself to the Madagascan forest 1,000 years ago. Tramping along, you notice a giant creature hanging by long, hook-shaped hands and feet from a tree branch. It lumbers along in slow motion, much like a sloth. But while a typical sloth weighs 12 pounds, this one tops 120. And unlike a sloth’s rodentlike face, this animal’s countenance is vaguely human, with big, intelligent eyes. It climbs down the trunk and crawls on its belly to a nearby tree. There an even odder animal sits, pawing at low branches. It looks similar to the first animal, with the same face and body. But at 500 pounds, it is as big as a bear.

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Discover, July 1, 1992

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Geologists have their own Atlantis: the Earth’s earliest crust. Over the eons, colliding plates have drowned the planet’s primordial crust, plunging it down into the hot mantle whence it came. The oldest rocks known to have escaped this recycling are 3.96 billion years old. By then Earth had been evolving for 600 million years.

Now two Harvard geochemists claim they have found a clear record of Earth’s first crust–or at least of when it formed. They say it formed within 100 million years after the planet itself coalesced (along with the rest of the solar system) from a swirling nebula of gas and dust. The evidence isn’t an actual rock; it’s a chemical footprint the crust left behind.

Continue reading “Lost World” →

Discover, May 31, 1992

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If you believe what you read in the papers, Sankar Chatterjee ought to be the crown prince of paleontology. Six years ago he announced that he had found the world’s oldest bird fossil. If beat the previous record not by a mere 1 or 2 million years but by 75 million. With one quick kick, it seemed, Chatterjee sent paleontologists who thought they knew something about how birds had evolved tumbling in the dust.

Discovering the oldest fossil of anything is obviously wonderful for a paleontologist’s career. The fossil instantly becomes the centerpiece of any future theory about how an animal evolved and what it evolved from. And not incidentally, the fossil finder becomes just as important.

Continue reading “Ruffled Feathers” →

Discover, April 1, 1992

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By the time Morrie Pongratz stepped outside to watch his experiment one night last July, the moon had set. But it couldn’t have competed with Pongratz’s experiment in any case. The experiment began at 3:37 a.m. eastern standard time, when a NASA satellite orbiting 270 miles overhead ejected two three-foot-long metal canisters, which then released 23 pounds of barium gas into space. Within seconds the barium blossomed into a giant yellow-green fireball, even bigger and brighter than a full moon. The release was spectacular, says Pongratz, a space physicist at Los Alamos National Laboratory. You’re on the ground in the dark, but up where the barium is, the sun is shining.

Continue reading “Making Auroras” →