What would you do if you had a spacecraft pushing toward the edge of the Solar System with nothing much to do? The answer is to assign it an extended mission, as we found out with the two Voyagers and their continuing data return that is helping us understand the boundaries of the heliosphere. In the case of New Horizons, NASA's probe to Pluto/Charon, two extended missions may be involved after Pluto, the first being a flyby of one or more Kuiper Belt targets, the second being a further look at what is actually going on where the solar wind meets the interstellar medium. Alan Stern, principal investigator for New Horizons, comments on the possibility in his latest report on the mission, noting that a second extended mission isn't out of the question, and adding that New Horizons won't make it as far as the Voyagers before it runs out of power. But 90 to 100 AU seems a possibility, which would provide a useful supplement to Voyager data. Remember that New Horizons carries two...

by Andreas Hein The immense problems of time, distance and life support invariably mean that when we talk about an interstellar mission, we talk about robotics. But the imaginative team at Icarus Interstellar, which is now setting up projects on everything from beamed lightsails (Project Forward) to pulse propulsion engines (Project Helios), has pushed into the biggest what-if of all, the question of manned missions. And as project leader Andreas Hein reminds us in the following article, a variety of approaches have been suggested for this over the years from which a new concept study can grow. Andreas Hein received his master's degree in aerospace engineering at the Technische Universität München, and is doing his PhD at the same university in the area of space systems engineering at the Institute of Astronautics. He has participated in several mission studies: a lunar gravity measurement mission by EADS and a cubesat mission analysis. During his internship at ESA-ESTEC, he...

Powering up a spacecraft is a lot easier to manage in the Sun-rich environment inside the orbit of Mars than it is out past the orbit of Jupiter. Solar panels provide plenty of power for a satellite in near-Earth orbit, for example, but moving into the outer system invokes the need for RTGs -- radioisotope thermoelectric generators -- powered by radioactive decay. If you read through the specs on the FOCAL mission design presented here last Friday, you saw that this attempt to reach the Sun's gravitational lens would demand 20 RTGs, and thus requires resumed production of plutonium-238. What's happened is that US production of 238Pu was halted as far back as 1988, leaving us with stockpiles that should be sufficient for missions in the pipeline through the end of this decade. That's the view of Leonard Dudzinski, NASA's Radioisotope Thermoelectric Generator program executive, who was speaking at the opening session of the 43rd Lunar and Planetary Science and the Nuclear and Emerging...

Long-time Centauri Dreams readers have learned to tolerate my eccentricities (or, at least, they’re kind enough not to dwell on them). One of them is my love of poking around in old books related to space travel, which is how Benjamin Field’s A Narrative of the Travels and Adventures of Paul Aermont Among the Planets (1873) recently caught my eye. I don’t know much about Field other than that he chose to produce this tale of interplanetary wanderings under a pseudonym, but what’s fun about his tale is that after his journeys to Jupiter, Saturn, Mars and Venus are over, Field’s protagonist returns to Earth to find that the planet is fully fifty years older, though he himself has aged hardly at all. Time dilation, the reader might say, but of course Field wouldn’t have known anything about special relativity. It’s fun to consider, though, how an idea that in 1873 would have been simple fantasy -- that someone might travel at high speed and age at a different rate than those he left...

One of the first things we need to do in terms of interstellar exploration is to get a spacecraft built for the purpose to travel outside the heliosphere and give us solid measurements on the interstellar medium. The Voyagers are doing their best but they were never designed for what has become their interstellar mission, and while we can marvel at their longevity, it's with the knowledge that their resources are few and their years of useful data gradually drawing to an end. Something along the lines of Ralph McNutt's Innovative Interstellar Explorer would do the job nicely, allowing us to sample the environment that much longer missions will have to work in. Lorentz Force Turning The interstellar medium (ISM) is important not just because we have to learn about things like shielding a fast-moving spacecraft and cosmic ray flux but also because we may be able to use some aspects of the medium for deceleration. Yesterday's discussion of magsails reminded me of a 1969 paper by P. C....

Imagine a future in which we manage to reach average speeds in the area of one percent of the speed of light. That would make for a 437-year one-way trip to the Alpha Centauri system, too long for anything manned other than generation ships or missions with crews in some kind of suspended animation. Although 0.01c is well beyond our current capabilities, there is absolutely nothing in the laws of physics that would prevent our attaining such velocities, assuming we can find the energy source to drive the vehicle. And because it seems an achievable goal, it's worth looking at what we might do with space probes and advanced robotics that can move at such velocities. How, in other words, would a spacefaring culture use artificial intelligence and fast probes to move beyond its parent solar system? John Mathews ( Pennyslvania State) looks at the issue in a new paper, with a nod to the work of John von Neumann on self-reproducing automata and the subsequent thoughts of Ronald Bracewell...

Andreas Tziolas, current leader of Project Icarus, gave a lengthy interview recently to The Atlantic's Ross Andersen, who writes about starship design in Project Icarus: Laying the Plans for Interstellar Travel. Icarus encounters continuing controversy over its name, despite the fact that the Icarus team has gone to some lengths to explain the choice. Tziolas notes the nod to Project Daedalus leader Alan Bond, who once referred to "the sons of Daedalus, perhaps an Icarus, that will have to come through and make this a much more feasible design." I like that sense of continuity -- after all, Icarus is the follow-on to the British Interplanetary Society's Project Daedalus of the 1970s, the first serious attempt to engineer a starship. I also appreciate the Icarus' team's imaginative re-casting of the Icarus myth, which imagines a chastened Icarus washed up on a desert island planning to forge wings out of new materials so he can make the attempt again. But what I always fall back on is...

Ralph McNutt's recent update on the progress of the Innovative Interstellar Explorer concept elicited plenty of comments, enough that Dr. McNutt wanted to answer them in a new post. Now at Johns Hopkins University Applied Physics Laboratory, McNutt is Project Scientist and a Co-Investigator on NASA's MESSENGER mission to Mercury, Co-Investigator on NASA's Solar Probe Plus mission to the solar corona, Principal Investigator on the PEPSSI investigation on the New Horizons mission to Pluto, a Co-Investigator for the Voyager PLS and LECP instruments, and a Member of the Ion Neutral Mass Spectrometer Team on the Cassini Orbiter spacecraft. With all that on his plate, it's hard to see how he has time for anything else, but McNutt also continues his work as a consultant on the Project Icarus interstellar design study. His Innovative Interstellar Explorer is a precursor mission designed to push our technologies hard. by Ralph McNutt I typically do not get involved with commenting on comments...

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 to Dr. McNutt about interstellar precursors back in 2003, when researching my Centauri Dreams book. Now at Johns Hopkins University Applied Physics Laboratory, the physicist's space experience is comprehensive. He is Project Scientist and a Co-Investigator on NASA's MESSENGER mission to Mercury, Co-Investigator on NASA's Solar Probe Plus mission to the solar corona, Principal Investigator on the PEPSSI investigation on the New Horizons mission to Pluto, a Co-Investigator for the Voyager PLS and LECP instruments, and a Member of the Ion Neutral Mass Spectrometer Team on the Cassini Orbiter spacecraft. He has published over 150 science and...

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 to extend the discussion to a third day. That kind of focus invariably means I get behind in other stories, though, so I want to be sure to catch up with matters like the recent news about the Voyagers as they continue to exit our system. I always point to the still functioning instruments of the Voyagers as an outstanding example of how we can build spacecraft for the long haul -- these tough platforms show what can be done with careful design, and future craft fully optimized for even longer flights certainly seem practical. In this case, three instrument packages -- the Cosmic Ray Subsystem, the Magnetometer and the Low Energy Charged...

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 concepts developed for use right here in the Solar System. Consider just one, a microwave-driven sail that could reach Mars in one month, and Pluto in five years. I wrote about this one in A Microwave-Beamed Sail for Deep Space. The idea comes from Jim and Greg Benford, who discussed it in a 2006 issue of the Journal of the British Interplanetary Society. The scenario involved a phenomenon the duo had discovered in their laboratory work on microwave beaming. Experimenting with a 7.5 g/m2 carbon sail, they had uncovered the fact that molecules evaporating from the sail created accelerations beyond what would have been expected from photons alone....

by K.F.Long, co-founder Project Icarus Kelvin Long is well known to Centauri Dreams readers. The physicist and aerospace engineer is, in addition to being one of the most energetic voices in the service of interstellar propulsion studies, the co-founder of Project Icarus, the successor to the 1970s-era Project Daedalus starship design study. Here Kelvin looks at where the ongoing Icarus effort stands in terms of fusion, placing that propulsion option in the context of the broader questions raised by pushing a payload to the stars. Back in December 2009 I wrote an article titled Project Icarus and the Motivation Behind Fusion Propulsion. This was an attempt to justify the initial design choice of the team as part of the engineering requirements for the study that is Project Icarus. Despite this article and other discussions we have had, we have recently learned something from our experience at the 100 Year Starship Study Symposium: People still don't understand the Daedalus connection...

The British Interplanetary Society's Kelvin Long is no stranger to these pages, perhaps best known as the founder and first leader of Project Icarus, but an indefatigable writer on interstellar topics as well. Kelvin's first book, Deep Space Propulsion: A Roadmap to Interstellar Flight, is scheduled for publication by Springer later this year. Fellow writer Pat Galea has a background in electronic engineering and physics, and has been a professional software engineer since 1993. As well as contributing to the Project Icarus starship design, he is a supporter of Monkey World in the UK, and a staunch advocate for preserving Bletchley Park, home of World War 2 code breaking. Both Long and Galea are Tau Zero practitioners as well. The duo here offer us an overview of a symposium Kelvin recently organized in London that as far as I know was a first: A conference entirely devoted to the breathtaking concept of interstellar colony craft potentially hundreds of kilometers long. by Kelvin F....

The first conference devoted solely to worldships takes place today in London at the headquarters of the British Interplanetary Society. It seemed a good time to check in with Gregory Matloff, a man I described when writing Centauri Dreams (the book) as the 'renaissance man of interstellar studies.' Perhaps best known for his continuing work on solar sails, Matloff's interests have nonetheless ranged widely. He brought deep space propulsion to a wide audience in his book The Starflight Handbook (1989), which covers the full spectrum of interstellar options, but for over three decades has continued to produce scientific papers investigating issues ranging from laser ramjets to beamed microwave missions. A recent interest has been the expansion of the human biosphere into space, as discussed in books like Paradise Regained: The Regreening of Earth (Springer, 2009) and the soon to be published Biosphere Extension: Solar System Resources for the Earth, written with C Bangs. These last...

by Richard Obousy After a stint as project leader for the Project Icarus starship design study, Richard Obousy now serves as Module Lead Primary Propulsion for the effort. Dr. Obousy's doctoral work at Baylor University focused on the possibility that dark energy could be an artifact of Casimir energy in extra dimensions. For Icarus, he has pivoted to the study of fusion propulsion systems for this ongoing reworking of the original Project Daedalus concept. He's also fascinated with the possibilities of getting off our planet more easily and establishing a human presence on Mars, all ideas he was able to explore at the Mars Society's latest meeting, from which this report. As a native of Texas, living only a couple of hours drive from Dallas, I was thrilled to discover that that was where the Mars Society planned to hold its 14th International Mars Society Convention. This was a perfect opportunity for me to meet space enthusiasts, to present to this community some of the ideas...

Anyone who looks back on Robert Heinlein's 'juvenile' novels, twelve books written for young adults between 1947 and 1958, as inspiration for his current work gets my attention. I loved every one of those novels, particularly Citizen of the Galaxy (1957) and Starman Jones (1953), but David Neyland says it was Time for the Stars (1956) that got him thinking about the 100 Year Starship Study. If you've been keeping up with Centauri Dreams, you know that the Defense Advanced Research Projects Agency (DARPA), which handles cutting-edge research and development for the US military, is putting on a starship symposium this fall in Orlando, FL. This follows up on the earlier DARPA Request for Information and will lead to the award of $500,000 or so in seed money to an organization that can best pursue the study's goals. Neyland, who is director of DARPA's Tactical Technology Office, has been explaining what the study is all about to newspapers like the Los Angeles Times, which ran a story on...

The Project Icarus team has founded a non-profit research organization called Icarus Interstellar, its goal being to 'foster research into those necessary technologies which can make interstellar research a reality' through the study of such topics as fusion, nanotechnology, advanced power sources and other critical drivers for interstellar flight. We've tracked Icarus here from the beginning, when it emerged as an ambitious attempt to update and re-think the original Project Daedalus starship design of the 1970s. Taking fusion as its propulsion mechanism, the Icarus team now seeks to analyze and design a probe in terms of recent advances in numerous fields. How do you go about designing a starship? Something this speculative, which must of necessity rely on extrapolations of where technology is going, happens outside the normal 9-5 workday. Centauri Dreams readers know that the Icarus team is composed of volunteers, most of whom work and exchange ideas over the Internet -- only a...

Talking about Mason Peck's notions of 'swarm' spacecraft -- probes on a chip that might reach interstellar speeds -- I'm inescapably drawn to the other end of the spectrum. A 'worldship' is a mighty creation that may mass in the millions of tons, a kilometer (or more) long vehicle that moves at a small fraction of the speed of light but can accommodate thousands, if not hundreds of thousands, of inhabitants. What promises to be the first scientific conference devoted solely to worldships is about to take place on Lambeth Road in London at the headquarters of the British Interplanetary Society. The day-long conference gets down to business on the morning of August 17. This BIS page offers a draft of the program. As the BIS has done in the past, all presentations from the conference will be written up in a special issue of the Journal of the British Interplanetary Society, where much of the early speculation on worldships has taken place. Several of the Project Icarus team will be...

The Tau Zero Foundation is pleased to announce that planet hunter extraordinaire Geoffrey Marcy is now affiliated with the organization. As a Tau zero practitioner, Dr. Marcy will serve as a major point of contact on exoplanet issues, bringing with him the most storied portfolio in the planet-hunting business. Working closely with Paul Butler and Debra Fischer, Dr. Marcy (University of California at Berkeley) has discovered more extrasolar planets than anyone else, including 70 out of the first 100 to be found. His team's findings include the first multiple-planet system, the first Saturn mass planets, and the first Neptune-mass planet. His awards are numerous: Shaw Prize in 2005, Discovery Magazine's Space Scientist of the Year in 2003, the NASA Medal for Exceptional Scientific Achievement, the Carl Sagan Award, the Beatrice Tinsley Prize, and the Henry Draper Medal from the National Academy of Sciences. A warm welcome, Geoff! Centauri Dreams readers will recall our coverage of the...