November 2008

A Bright Flare, and a Warning

November 29, 2008

One night about ten years ago I was walking down a quiet road on Emerald Isle, NC, the spring air spangled with stars, when a meteor flamed across the sky with such vehemence that I fully expected to hear the sound of an impact. I didn’t, of course, and on the normal scale of things, […]

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Enceladus: Evidence for Liquid Water

November 28, 2008

The phrase ‘liquid water’ is enough to quicken the pulse of the steeliest-eyed astrobiologist. We’ve long defined the concept of a habitable zone — that zone around a star in which life might flourish — by the presence of liquid water at the surface. But as we start pondering liquid water beneath the ices of […]

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Building for the Long Haul

November 26, 2008

When you’re thinking long-term, a period of 5.7 years seems like a mere blip in time. But NASA’s Long Duration Exposure Facility, deployed from the shuttle Challenger in 1984 and returned to Earth after 32,422 orbits, is a small-scale experiment that points to much weightier objectives. Think about the Voyager spacecraft, launched in 1977 and […]

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More Cosmic Ray ‘Hot Spots’

November 25, 2008

As we learn more about cosmic rays, it becomes clear that these incoming particles — protons and electrons accelerated to high energy levels — do not reach us uniformly. Just a few days ago we saw that the ATIC (Advanced Thin Ionization Calorimeter) experiment had revealed a source of cosmic rays relatively close to the […]

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Notes & Queries 11/24/08

November 24, 2008

What might make a star particularly interesting from a SETI point of view? Bruce Cordell looks at the question in a post in the latest Carnival of Space, drawing on a JBIS article by Martin Beech (“Terraformed Planets and SETI,” February 2008). The method seems to be to examine the ratio of a star’s age […]

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Planet Imaged Around Beta Pictoris?

November 22, 2008

Images of distant exoplanets, once only a wish for future space missions, have begun to turn up with a certain regularity. The three planets around HR8799 and the single gas giant around Fomalhaut were announced on the same day, while a week later we once again have Beta Pictoris in focus, a young star so […]

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An Internet for Deep Space

November 21, 2008

Networking deep space should be a priority for future missions. If we can set up robust networking between spacecraft, we relieve the Deep Space Network of a huge burden, that of having to communicate directly with each spacecraft for tasks that are essentially routine. No more maneuvering huge dishes to catch one fleeting signal, at […]

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High-Energy Electrons: Evidence for Dark Matter?

November 20, 2008

What is the unusual source of high-energy cosmic rays that has been discovered within 3000 light years of the Sun? Everyone loves a mystery, and this one has all the earmarks of a classic. The source was found by the Advanced Thin Ionization Calorimeter (ATIC) experiment, which was lofted to high altitude above Antarctica via […]

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Searching for Dyson Spheres

November 19, 2008

A Dyson Sphere makes an extraordinary setting for science fiction. In fact, my first knowledge of the concept came from reading Larry Niven’s 1970 novel Ringworld, a book that left such an impression that I still recall reading half of it at a sitting in the drafty little parlor of a house I was renting […]

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Billions of Positrons Created in Laboratory

November 18, 2008

Irradiate a millimeter-thick gold target with the right kind of laser and you might get a surprise in the form of 100 billion positrons, the antimatter equivalent of electrons. Researchers had been studying the process at Lawrence Livermore National Laboratory, where they used thin targets that produced far fewer positrons. The new laser method came […]

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