May 2011

Simulating Moons Around Terrestrial Planets

May 31, 2011

Just how the Moon originally formed is under renewed scrutiny given the finding that it contains larger amounts of water than previously thought. We’ll look at that issue in depth another time, because it’s far from resolved. The generally accepted account of the Moon’s formation involves a giant impact with a planetary embryo that has […]

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‘Blue Stragglers’ in the Galactic Bulge

May 30, 2011

I’m fascinated by how much the exoplanet hunt is telling us about celestial objects other than planets. The other day we looked at some of the stellar spinoffs from the Kepler mission, including the unusual pulsations of the star HD 187091, now known to be not one star but two. But the examples run well […]

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On the Calendar: Exoplanets and Worldships

May 27, 2011

Be aware of two meetings of relevance for interstellar studies, the first of which takes place today at the Massachusetts Institute of Technology. There, a symposium called The Next 40 Years of Exoplanets runs all day, with presentations from major figures in the field — you can see the agenda here. I bring this up […]

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OSIRIS-REx: Sampling an Asteroid

May 26, 2011

Asteroid 1999 RQ36 may or may not pose a future problem for our planet — the chances of an impact with the Earth in 2182 are now estimated at roughly one in 1800. But learning more about it will help us understand the population of near-Earth objects that much better, one of several reasons why […]

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Beyond the Kepler Planets

May 25, 2011

Kepler is a telescope that does nothing more than stare at a single patch of sky, described by its principal investigator, with a touch of whimsy, as the most boring space mission in history. William Borucki is referring to the fact that about the only thing that changes on Kepler is the occasional alignment of […]

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Progress Toward the Dream of Space Drives and Stargates

May 23, 2011

by James F. Woodward I first wrote about James Woodward’s work in my 2004 book Centauri Dreams: Imagining and Planning Interstellar Exploration, and have often been asked since to comment further on his research. But it’s best to leave that to the man himself, and I’m pleased to turn today’s post over to him. A […]

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Support for Dark Energy

May 20, 2011

The far future may be a lonely place, at least in extragalactic terms. Scientists studying gravity’s interactions with so-called dark energy — thought to be the cause of the universe’s accelerating expansion — can work out a scenario in which gravity dominated in the early universe. But somewhere around eight billion years after the Big […]

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New Findings on Rogue Planets

May 19, 2011

Gravitational microlensing to the rescue. We now have evidence for the existence of the rogue planets — interstellar wanderers moving through space unattached to any star system — that we talked about just the other day. It’s been assumed that such planets existed, because early solar systems are turbulent and unstable, with planetary migrations like […]

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New Views of a Cometary Core

May 18, 2011

We looked recently at Titan Mare Explorer (TiME), a mission to land a probe on Titan’s Ligeia Mare, a methane-ethane sea that would be observed for an extended period by this floating observatory. But I don’t want to pass too quickly over Comet Hopper, one of the other missions being considered by NASA’s Discovery Program. […]

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Finding an Interstellar Wanderer

May 17, 2011

Imagine a planet far more massive than Jupiter and spinning faster than Jupiter’s 10 hour rotation. Throw in a large nearby moon and the associated auroral effects that would occur as the moon moved through fields of plasma trapped in the planet’s magnetic field. The scenario isn’t all that different from what we see happening […]

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