April 2005

Physical Constant Unchanged After All?

April 19, 2005

More on the ‘fine structure constant,’ that fundamental number that seems to be crucial to our understanding of electromagnetism, and therefore the way the universe works. Our recent story on Michael Murphy and his Cambridge team discussed findings from the Keck I telescope on Mauna Kea that suggested subtle changes to the value of the […]

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Interstellar Flight by Particle Beam Revisited

April 18, 2005

Beamed propulsion is the classic solution to the mass ratio problem in interstellar flight. Rather than pushing more and more fuel to get your payload to another star system, you leave the fuel behind. Robert Forward’s vast lightsail proposals come immediately to mind, but in 2001 physicist Geoffrey Landis proposed propulsion by particle beam, with […]

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SETI? Here’s Why We Need to Keep Looking

April 16, 2005

“A recent book by the mathematician Amir Aczel makes the case for the probability of extraterrestrial life being 1. The physicist Lee Smolin wrote that ‘the argument for the non-existence of intelligent life is one of the most curious I have ever encountered; it seems a bit like a ten-year-old child deciding that sex is […]

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Tuning Up Terrestrial Planet Finder

April 15, 2005

We’ve recently discussed habitable zones, normally defined as the area around a star where liquid water can exist on the surface. Thoughts on just how far the habitable zone around our own star extends vary, but the Carnegie Institution’s Maggie Turnbull pegs it at between .7 AU and 1.5 AU. To adjust the notion of […]

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Oort Cloud Explorer: Fast Mission to the Comets

April 14, 2005

How do you build an interstellar solar sail? Back in the 1980s, two studies of sail design set parameters that before then had remained largely unanalyzed. Gregory Matloff and Eugene Mallove were able to show in their papers “Solar Sail Starships: Clipper Ships of the Galaxy” and the later “The Interstellar Solar Sail: Optimization and […]

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Extremely Large Telescopes and the Hunt for Terrestrial Worlds

April 13, 2005

How large can a telescope get? Today’s largest optical telescopes boast 10-meter mirrors (33 feet across). But the recent Royal Astronomical Society meeting in Birmingham (UK) heard the case for much larger instruments, on the order of 50 to 100 meters (165-330 feet) in diameter, optical instruments the size of the Deep Space Network’s largest […]

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Voyager and the Benefits of ‘Slow Science’

April 12, 2005

The Washington Post takes note of the possible suspension of funding for the two Voyager spacecraft in a story by Rick Weiss called Our Incredible Shrinking Curiosity. As discussed here in a previous entry, NASA is eying the Voyager budget of $4.2 million per year as it ponders cutbacks. Such news, says Weiss, leaves him […]

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Fundamental Constant May Need Tweaking

April 11, 2005

Michael Murphy has been studying the fundamental constants of nature — numbers that are key to any given theory of how the universe works — for the past five years. His work at the Institute of Astronomy at Cambridge University has particularly foused on possible changes to the fine structure constant, a number central to […]

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GQ Lupi B: Exoplanet or Brown Dwarf?

April 9, 2005

The recent image of a possible planet around the star GQ Lupi has met with understandable enthusiasm in the press, but we still don’t know whether the small object just to the right of the star in the image below is a planet or a brown dwarf. The boundary between brown dwarf and planet is […]

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Emergence of the ‘Dark Energy Star’

April 8, 2005

“It’s a near certainty that black holes don’t exist,” says George Chapline. A physicist at the Lawrence Livermore National Laboratory, Chapline has an alternative explanation: when a massive star collapses, what remains is not a black hole but a star that’s filled with dark energy. Some 70 percent of the universe seems to be composed […]

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