Interstellar Medium

Pushing Up Against Lightspeed

February 19, 2010

Time dilation has long been understood, even if its effects are still mind-numbing. It was in 1963 that Carl Sagan laid out the idea of exploiting relativistic effects for reaching other civilizations. In a paper called “Direct Contact Among Galactic Civilizations by Relativistic Interstellar Flight,” Sagan speculated on how humans could travel vast distances, reaching […]

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Mapping the Interstellar Medium

February 10, 2010

We’ve long known that the spaces between the stars are not empty, but are pervaded by a highly dilute mix of gas and dust. Now we’re getting maps that show the presence of large cavities in this interstellar medium, created by supernova events as well as outflowing solar winds from clusters of hot, young stars. […]

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Cyclers: Transportation Network Among the Stars?

January 1, 2010

Last July at the Aosta conference Greg Matloff presented a paper on using near-Earth objects for transportation. It’s an interesting concept (discussed here), one that takes advantage of the fact that there are a few such objects that pass close by the Earth and then go on to cross the orbit of Mars. Greg was […]

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Voyagers Look at the Edge of the Solar System

December 30, 2009

We always cite the Mars rovers as examples of missions that perform far beyond their expected lifetimes, but the two Voyager spacecraft are reminding us once again that we have instrumentation at the edge of the Solar System that is still functioning after all these years. Both Voyagers are now in the heliosheath, the outermost […]

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A New Shape for the Heliosphere

November 23, 2009

One problem with journeys that are beyond today’s technologies is that we forget, in our zeal to get a payload to the target, how little we know about the regions we’ll pass through along the way. It’s amazing how little we know, for example, about the heliosphere around the Solar System, yet any probe pushing […]

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Reshaping the Solar System

October 16, 2009

Yesterday’s story on IBEX is now complemented by images from the Ion and Neutral Camera, part of the Magnetospheric Imaging Instrument on the Cassini orbiter. The Cassini data confirm the fact that the heliosphere isn’t shaped the way we’ve always thought. The assumption up to now has been that the collision of the solar wind […]

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A Surprise at the Termination Shock

October 15, 2009

Findings that are outside our expectations seem par for the course as we explore the Solar System. From the volcanoes of Io to the geysers of Enceladus, unusual things show up with each new mission. Why should IBEX be any different? The Interstellar Boundary Explorer is the first spacecraft expressly designed to study what happens […]

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Heliospheric Crossings (and the Consequences)

September 30, 2009

Below you’ll see that I’m running Mike Brown’s sketch of the ‘new’ Solar System, one I originally ran with our discussion of Joel Poncy’s Haumea orbiter paper, which was presented at Aosta in July. The sketch is germane on a slightly different level today because as we look at how our views of the Solar […]

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Shielding the Starship

April 3, 2009

“Interstellar travel may still be in its infancy,” write Gregory Matloff and Eugene Mallove in The Starflight Handbook (Wiley, 1989), “but adulthood is fast approaching, and our descendants will someday see childhood’s end.” The echo of Arthur C. Clarke is surely deliberate, a sign that one or both authors are familiar with Clarke’s 1953 novel […]

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Dust Up Between the Stars

February 9, 2009

Almost four years ago I wrote a Centauri Dreams entry about Dana Andrews’ views on shielding an interstellar spaceship. The paper is so directly relevant to our recent discussion on the matter that I want to return to it here. Andrews (Andrews Space, Seattle) believes that speeds of 0.2 to 0.3 c are attainable using […]

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