Meg Urry

Nota: Este archivo abarca los artículos publicados por el autor desde el 1 de Abril de 2008. Para fechas anteriores realice una búsqueda entrecomillando su nombre.

Unless you have been, well, on another planet, you know that July 14 was the date of closest approach to Pluto by the New Horizons spacecraft, which has now sent back unprecedented images from this historic encounter.

Passing Pluto at barely 7,750 miles (or 12,400 kilometers for savvy metric readers), the seven experiments on the New Horizons spacecraft are busily gathering extensive data on Pluto and its five known moons, Charon, Styx, Nix, Kerberos and Hydra.

It will be months before these data are fully transmitted to Earth, in part because, like many of us, New Horizons needs to focus all its effort on one essential task at a time.…  Seguir leyendo »

The march into space appears to be gathering speed. The not-for-profit Mars One says it plans to establish a human settlement on Mars by 2025, a goal that has attracted more than 200,000 applicants for the one-way trip (a number that has so far been winnowed down to 705 candidates). And before Virgin Galactic’s SpaceShip2 crashed in October, nearly a thousand would-be space tourists spent as much as a quarter of a million dollars for the promise of a few minutes of suborbital weightlessness.

But, future astronauts, think very carefully: Space is a very dangerous and unpredictable place.

For decades, space scientists have used an array of sophisticated satellite experiments to study the environment of space from the Earth to the sun.…  Seguir leyendo »

Durante la última semana y media, la gente se ha maravillado con el descubrimiento de las pruebas que respaldan la «inflación», teoría que describe los dolores de parto del Big Bang hace 13,700 millones de años. ¿Qué significan estos hallazgos y cómo se descubrieron?

En muchos artículos se dio a conocer la noticia, pero yo trataré de explicarla a fondo. No se vayan, porque este es uno de los descubrimientos astrofísicos más emocionantes en varias décadas.

Los humanos se han preguntado por el origen del universo desde hace milenios; la noticia de la semana pasada nos acercó un poco más a la respuesta.…  Seguir leyendo »

The other night, as I sat in the telescope operation room at the Keck Observatory in Waimea, Hawaii, preparing with colleagues to measure light from some of the most distant galaxies known, the phone rang with startling news.

An exploding star had been sighted in M82, one of the nearest big galaxies. The «supernova» (as such stellar explosions are called) was a special, rare «Type Ia» — the kind that led to the Nobel-worthy discovery of dark energy.

Type Ia supernovae have happened in our galactic neighborhood only three times in the last 80 years. Like astronomers around the world, we were excited to be at a world-leading telescope, where we could collect new information about this rare event.…  Seguir leyendo »

A mile down in an abandoned gold mine in South Dakota, physicists in a state-of-the-art scientific laboratory are searching for elusive «dark matter» particles, which make up most of the mass in our universe.

So far, no one has ever seen dark matter directly. You can’t see it, touch it, smell it, throw a net over it, or tag it in the ways particle physicists deal with ordinary particles. We only know it by its gravitational effects on galaxies.

On Wednesday, team members from LUX — for Large Underground Xenon experiment — announced the first results from their operation in the Sanford Underground Research Facility, deep in the former Homestake Mine in Lead, South Dakota — where for three months they have been taking an 11-minute, 4,850 foot elevator ride down a mine shaft to work in their lab.…  Seguir leyendo »

El 27 de abril, los satélites Fermi y Swift de la NASA detectaron una fuerte señal proveniente del brote de rayos gamma más brillante en décadas.

Debido a que se encontraba relativamente cerca, fue miles de veces más deslumbrante que otros que el Swift observa frecuentemente. Los científicos ahora tratan de saber más.

Sabemos que cuando a las estrellas más grandes se les agota el combustible, no se desvanecen en silencio. En cambio, su explosión es grandiosa y se convierten en lo que conocemos como supernova. Con frecuencia, estas transformaciones estelares son lo suficientemente brillantes como para poder verlas, incluso, si se encuentran en galaxias a miles de millones de años luz de nuestro hogar, en la Vía Láctea.…  Seguir leyendo »

Is anybody out there?

For millennia, humans have gazed at the night sky, asking this question. That’s why scientists and NASA are eagerly searching for «exoplanets» — that is, planets that orbit around stars other than our sun.

Last week NASA’s Kepler satellite reported the discovery of three Earth-sized exoplanets within the so-called «habitable zone,» defined as the neighborhood of a star where liquid water — essential for life as we know it — can exist.

In our solar system, only three planets lie in the sun’s habitable zone — Venus, Earth and Mars.

Planets too close to the star they orbit, like Mercury, are too hot for liquid water.…  Seguir leyendo »

Friday was an extremely unusual day, astronomically speaking. Just as scientists were gearing up to witness an asteroid’s closest ever approach to Earth in recorded history, a sizeable meteor exploded over Russia, causing thousands of injuries and major damage to buildings.

The asteroid, named DA14, came within 17,000 miles or so, as close as a telecommunication satellite in geosynchronous orbit. DA14 is quite a bit smaller than YU55, the asteroid that passed Earth in November 2011, but DA14 came more than 10 times closer.

These two rare events occurred the same day. Your inner mathematician and your inner prophet of the end times think they should be connected.…  Seguir leyendo »