I’m always interested in how work on interstellar concepts gets funded. After all, although the Nancy Grace Roman telescope is now ready to fly, with a launch some time this fall, there was a real chance the project might get canceled along the way. Trying to predict what will happen to NASA’s budget is harder now than ever. Thus I followed Marshall Eubanks and team’s work on swarm technology missions to Proxima Centauri with interest, learning in their new paper that their NIAC funding continues along with a grant from Breakthrough Starshot’s Communications Group. That last is itself interesting, as communications was, I’ve been told, the toughest nut to crack in setting up swarm strategies for tiny sailcraft – a few grams each – for Proxima Centauri b. Some of this work was performed at the Jet Propulsion Laboratory as well. Imagine our swarm as consisting of 1000 lightsails launched in a one-month window, boosted by the kind of laser array Breakthrough Starshot has advocated, an...

Because I’ve been talking about enormous structures lately and describing them as ‘big dumb objects,’ I thought it would be fun to revisit the origin of that term. BDOs emerged in what was intended as an April Fool’s joke by writer and critic Peter Nicholls, famed as editor (with John Clute) of The Encyclopedia of Science Fiction, now online in its fourth edition. He describes the genesis of the term in a well known essay called “Big Dumb Objects and Cosmic Enigmas: The Love Affair between Space Fiction and the Transcendental”: “All these matters were in the forefront of my mind when I came to revise The Encyclopedia of Science Fiction, a task in which my primary responsibility was to rewrite and rethink all those entries dealing with the themes of science fiction. This brings us to April Fool’s Day, 1992, that being a day in which practical jokes are traditionally carried out. On that day I was exhausted writing theme entries, and my brain was hurting. So I decided to write an April...

Sometimes I jog my perspective on thorny physics issues by going back to earlier work. At our all too infrequent dinners together, Claudio Maccone used to tease me about this, saying that older scientific papers had inevitably been superseded by recent work which would, in any case, incorporate the early documents. But I find that looking at an idea afresh sometimes means re-living its inception, which puts things in context. It was in that spirit that I recently revisited a key paper by Ronald Bracewell.

The second part of Jim Benford's examination of Breakthrough Starshot concludes our look at the numerous issues advanced by Phase I of the project. Largely discounted in recent press coverage, the Starshot effort in fact completed a successful Phase I and left behind numerous papers that illuminate the path forward for interstellar flight. This is solid work on everything from laser arrays to metamaterials and the engineering of data return at light-year distances. Read on. by James Benford “I have learned to use the word ‘impossible’ with great caution.” -- Wernher Von Braun, after the lunar landing In this second report, I will describe the major results of Starshot beginning with the mission scenario and then treating each major technical area in terms of how solutions have been resolved and issues retired. In Part 1, I described Phase 1 objectives. One of the causes of Starshot results not being well-known publicly is that the Breakthrough Foundation has not publicized its events...

The fortunes of Breakthrough Starshot have been the subject of so much discussion not only in comments in these pages but in backchannel emails that it is with relief that I turn to Jim Benford's analysis of a project that has done significant work on interstellar travel and is still very much alive. Jim led the sail team for several of his eight years with Breakthrough Starshot and was with the project from the beginning. In this article and a second that will run in a few days, he explains how and why press coverage of the effort has been erroneous, and not always through the fault of writers working the story. Let's now take a look at what Starshot has accomplished during its intensive Phase I. by James Benford "Make no mistake -- interstellar travel will always be difficult and expensive, but it can no longer be considered impossible." – Robert Forward Breakthrough Starshot has not failed, nor has it been canceled. Phase I of the program achieved its stated objectives: to...

A mission to the Sun’s gravity focus – or more precisely, the focal ‘line’ we might begin to use at around 650 AU – is never far from my mind. Any interstellar mission we might launch within the next thirty years or so (think Breakthrough Starshot, about which more next week) will essentially be shooting blind. We have little idea what to expect at Proxima Centauri b, if that is our (logical) target. But a mission to the solar gravity focus (SGL) would give us a chance to examine any prospective target at close hand. Indeed, so powerful are the effects if we can exploit this opportunity that we should be able to see continents, weather patterns, oceans and more if we can disentangle the Einstein Ring that the planet’s image forms as shaped by general relativity. We’ve discussed the phenomenon many a time: The Sun’s gravitational well so shapes the image of what is directly behind it as seen from the SGL so as to produce stupendous magnification, the image served up as a ‘ring’ around...