April 2008

Ancient Galaxies Packed with Stars

April 30, 2008

Just how different were things in the early universe? One answer comes from a study of galaxies whose light has taken eleven billion years to reach us. In this early era — the universe would have been less than three billion years old — researchers have found galaxies so unusually compact that they compress a [...]

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The ‘Great Filter’ Tackles Fermi

April 29, 2008

Suppose for a moment that life really is rare in the universe. That when we are able to investigate the nearby stars in detail, we not only discover no civilizations but few living things of any kind. If all the elements for producing life are there, is there some kind of filter that prevents it [...]

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Surface Oceans Around Distant Stars

April 28, 2008

Would large amounts of water on the surface provide a glint of light in both the infrared and visible spectrum if we study a distant exoplanet long enough? That’s the premise of an investigation now in progress, one aiming to find Earth-like planets in the habitable zone of a star. Darren Williams (Penn State Erie) [...]

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Dark Matter: Flashes Beneath the Earth

April 26, 2008

Dark matter is interesting in its own right, a mysterious ‘something’ that according to WMAP data must account for 23 percent of the universe (the breakdown now thought to be 72 percent dark energy, 23 percent dark matter, 4.6 percent atoms and less than 1 percent neutrinos). From a propulsion standpoint, dark matter intrigues us [...]

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Down and Dirty in the Data

April 26, 2008

astroENGINE.com hosts the 51st Carnival of Space, a lengthy compilation indeed, from which I’ll draw Ian Musgrave’s interesting post on a possible transit at 83 Leonis as the feature of the week. If you want to find out what it’s like to get your hands dirty juggling the data, trying to sift out signal from [...]

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Degrees of Visibility

April 25, 2008

Alexander Zaitsev’s latest contribution to the debate over sending messages to the stars is a short paper that looks at how visible our planet might be thanks to transmissions from planetary radars like Arecibo, Goldstone or the Evpatoria site from which directed transmissions have already been sent. METI (Messaging to Extra-Terrestrial Intelligence) is broadly dedicated [...]

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Electric Sails: Leave the Propellant at Home

April 24, 2008

A Finnish design making the news recently is hardly the only concept for near-term space sailing, but the possibility of testing it in space for a relatively small sum of money is attractive. This is especially true at a time when strapped budgets like NASA’s are focused on ratcheting up conventional propulsion techniques to get [...]

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Hawking and the Long Result

April 23, 2008

Sometimes it’s hard to believe that Stephen Hawking is only sixty-six. Not just because of his indomitable fight against Lou Gehrig’s disease, which is a story in its own right, but because his position at the summit of modern physics has kept him in the public eye for an exceedingly long time. Now, in a [...]

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A ‘Hot Jupiter’ in Our Solar System?

April 22, 2008

Serendipity is a wondrous thing. Start writing about the early history of the Solar System, as I intended to do yesterday, and you wind up discussing ‘hot Jupiters’ around other stars. But there actually is a bridge between the two concepts, and it comes in the form of a question. If we find gas giants [...]

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Habitable Worlds and Hot Jupiters

April 21, 2008

What happens to potentially habitable planets when a gas giant swings through the neighborhood? It’s a pertinent question when you consider the surprises that ‘hot Jupiters’ have given us. 22 percent of known extrasolar planets show an orbital radius of less than 0.1 AU, and 16 percent are located within 0.05 AU of their host [...]

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