‘Space’ Archives
Update on Innovative Interstellar Explorer
by Ralph McNutt Because of the interest that the Innovative Interstellar Explorer mission generates whenever I write about it, I was pleased to receive Ralph McNutt’s latest update on IIE. This was written in response to a recent article in these pages on the Voyager missions and refers to several of the comments in that thread. I first talked [...]
Into the Planetary Rainforest
So-called ‘super-Earths,’ planets larger than the Earth but smaller than Neptune, pose problems to our theories of planet formation. The most recent illustration of this came in the announcement that the candidate planets found by Kepler had now reached 2,326. Remember, many of these will not be confirmed — they’re candidates — [...]
Spaceflight and Legends: A Dialogue with Michael Michaud
I’ve been hoping to publish a dialogue between Michael Michaud and myself ever since talking to him at the 100 Year Starship Symposium and pondering his paper “Long-Term Perspectives on Interstellar Flight.” Centauri Dreams readers will know Michael as the author of the must-have Contact with Alien Civilizations: Our Hopes and Fears [...]
Voyager in the Doldrums
One of the pleasures of writing Centauri Dreams is digging into a paper to look at it from various directions, as I did recently with Jim Benford’s work on cost-optimized beamed sails. Jim has been working on these concepts for a long time, and although I had originally intended to devote two days to his latest, the depth of his analysis led me [...]
Notes Queries 12/14/11
I normally scan through various news items for the Notes & Queries posts, but in this case I’ve been trying to catch up on my reading. In particular, I’ve been looking at books that could be useful in inspiring young people to get interested in astronomy and engineering. Here’s a look at three titles that more or less fit that bill. The [...]
A Path Forward for Beamed Sails
Minimizing the cost of a project is no small matter because, as Jim Benford points out in the paper we’ve been examining over the past several days, cost determines how we decide on competing claims for resources. In the case of a beamed sail mission and its infrastructure, the cost is largely the reusable launcher or ‘beamer,’ which is the [...]
Optimizing Interstellar Mission Costs
Although we frequently talk about beamed sails for interstellar missions, the fact is that spacecraft on the scale Robert Forward used to talk about that could take us to Alpha Centauri in 40 years won’t come out of nowhere. The evolution of the solar sail into the beamed sail will involve all kinds of experimentation and a variety of mission [...]
The Case for Beamed Sails
There is a natural path through solar sails, which are now flying, toward beam-driven propulsion, and it’s a path Jim Benford has been exploring for the last eighteen years. In my Centauri Dreams book I described how Jim and brother Gregory ran experiments demonstrating that carbon sails could be driven by microwave beams back in the year 2000. [...]
New Worlds Targeted by Allen Telescope Array
The on-again, off-again SETI search at the Allen Telescope Array is back in business as Jill Tarter and team focus in on some of the more interesting worlds uncovered by the Kepler space telescope and follow-up observations. You’ll recall that last April the ATA was in hibernation, having lost its funding from the University of California at [...]
Detecting a ‘Funeral Pyre’ Beacon
Beamed propulsion continues to be a particular fascination of mine, which is why I want to start a discussion tomorrow of Jim Benford’s latest paper on beamed sails and how they might be optimized for both performance and cost. Reading through Benford’s work, however, I also came across Chris Wilson’s recent articles in Slate, which discuss [...]
