Revista Scientific American Febrero 2016. Inglés

Revista Scientific American Febrero 2016. Inglés

ISSN: 0036-8733

Descripción

Hidden “Planet X” Could Orbit in Outer Solar System
In the far reaches of the solar system, a hidden planet larger than Earth may be lurking

By Michael D. Lemonick
Something very odd seems to be going on out beyond Pluto. Astronomers have known for more than two decades that the tiny former planet is not alone at the edge of the solar system: it is part of a vast cloud of icy objects known collectively as the Kuiper belt. But unlike most of their fellow travelers, and unlike the planets and most asteroids, which orbit between Mars and Jupiter, a small handful of Kuiper belt objects, or KBOs, have orbits that are decidedly weird. For one thing, they take unusually elongated paths around the sun, unlike the roughly circular orbits of most planetary bodies.

One bright October afternoon on a beach in San Juan, Puerto Rico, two scientists found the solution to a problem that didn’t yet exist. It was 1979. Gilles Brassard, then a newly graduated Ph.D. from Cornell University, was immersed in the warm Caribbean water when someone swam toward him. The dark-haired stranger launched into a pitch about how to make a currency that could not be counterfeited. The scheme, invented several years earlier by a Columbia University graduate student named Stephen Wiesner, involved embedding photons particles of light in banknotes. By the laws of quantum mechanics, any attempt to measure or copy the photons would instantaneously change their properties. Each bill would have its own string of photons, a quantum serial number that could never be duplicated.