Tau Zero's founding architect (and the former head of NASA's Breakthrough Propulsion Physics project) weighs in on the kind of technology we see in the new Star Trek movie and ponders what it would take to make at least some of it real. by Marc Millis Another Star Trek film just hit the screen - with the venerable Starship Enterprise and its iconic warp drives and in-flight gravitation. How close are we toward realizing such a fantastic "Starship Enterprise"? How do such visions compare to other starflight pursuits? And finally, what is being done about it? STARFLIGHT CHALLENGES AND OPTIONS To send a spacecraft to our nearest neighboring star system (Alpha Centauri is over 4 lys distant) within a human lifespan would require a speed of roughly 1,000 times faster than the Voyager spacecraft. The two Voyager spacecraft were launched by NASA about 3 decades ago, and are just now passing through the edge of our solar system, at a distance of roughly 1/500th of a light year. To increase...
Posting Problems
Marc Millis' article "Star Trek, Star Tech," posted on Friday, has been taken down temporarily due to server problems that are now being investigated. As soon as I get these ongoing site maintenance issues resolved, the article will be reposted.
The Enzmann Solution
Yesterday I remarked on how many more tools for exoplanet discovery we have today than were available to Harry Stine when he wrote "A Program for Star Flight" in 1973. That same day came the disheartening news that the Kepler mission has been stopped in its tracks by an equipment malfunction. But take heart -- a vast amount of data already gathered by Kepler remains to be studied, meaning we'll be getting Kepler discoveries for some time to come. The Kepler news also sharpens our focus on TESS (Transiting Exoplanet Survey Satellite), which will build our catalog of nearby stars hosting exoplanets, with launch now scheduled for 2017. For more on Kepler, see Dennis Overbye's Breakdown Imperils NASA's Hunt for Other Earths. But back to Stine, who in 1973 was hunting not only for target exoplanets but also for a propulsion system that would get a human crew to them. He was evidently familiar with Eugen Sänger's papers on photon rockets, in which the German designer proposed deflecting...
Harry Stine: Building the Infrastructure
Before getting started on today's post, a reminder that Tau Zero founder Marc Millis and I will be among those interviewed on the History Channel show Star Trek: Secrets of the Universe tonight at 10 PM Eastern US time (0200 UTC on Thursday). Many of the ideas discussed on that show parallel those found in Harry Stine's program for interstellar exploration. Stine drew on the work of Stephen Dole, whose 1964 book Habitable Planets for Man identified 14 stars within a distance of 22 light years in the spectral classes between M2 and F2. Dole thought there was a 43 percent probability of at least one habitable planet around one of these 14 stars, and Stine's interstellar program began with a series of probes that would investigate them, looking first for gas giants. The idea is that a gas giant flags the presence of other, smaller planets, key information in Stine's day. Forty years later, we know how to find gas giants through radial velocity and transit studies. It's true that 'hot...
A Program for Star Flight
We become so bedazzled by the assumptions of our time that we can forget how things looked in different eras. 1973 wasn't all that many years ago in the cosmic scheme of things, but the early '70s were a time of surprising optimism when it came to our future in space. As we saw yesterday, physicist Robert Forward laid out a plan for interstellar expansion to a subcommittee of the U.S. House of Representatives in 1975, even as a thoughtful Michael Michaud worked out his own concepts in a series of papers in the Journal of the British Interplanetary Society. But nudging ahead of both men by a few years was G. Harry Stine. Already making a name for himself as a science fiction writer under the pseudonym Lee Correy, Stine was a futuristic thinker who fired readers' imaginations with a cover article in the October, 1973 Analog, an issue whose artwork I reproduce here. Rick Sternbach's cover caught my eye when I first saw this issue while toiling as a grad student that year, but it was the...
Roadmap to the Stars
Tau Zero founder Marc Millis and I will be among those interviewed on the upcoming History Channel show Star Trek: Secrets of the Universe, which will air this Wednesday at 10 PM Eastern US time (0200 UTC on Thursday). Being a part of this production was great fun, especially since it meant flying out to Oakland for a visit with my son Miles, who is now actively involved in interstellar matters. On long car trips when he was a boy, I would have Miles read Heinlein, Andre Norton and the like aloud while I drove -- terrific memories -- so you can imagine what a kick it is to see him as mesmerized by the human future in space as I am. The idea of getting a payload to another star seemed closer in the days of those car trips. I'm sure that's because we were coming off the successful Apollo program and assumed that a similarly directed effort could push us rapidly to the edge of the Solar System and beyond. It was in 1975, the year of the Apollo-Soyuz Test Project (the last time an Apollo...
The Growth of Interstellar Organizations
The British Interplanetary Society was founded way back in 1933, and included such luminaries as Arthur C. Clarke and Val Cleaver among its early membership. The Institute for Interstellar Studies (I4IS), also based in London, was founded in 2012 and is not, to the best of my knowledge, yet incorporated. Between the two dates and mostly emerging in the first decade of the 21st Century are a number of organizations that in one way or another focus on what I call 'interstellar studies,' meaning science and engineering dedicated to interstellar flight. The trick becomes to keep everything straight. When I started writing my Centauri Dreams book back in 2002, the BIS was a clear model for what a small group of dedicated workers could achieve. It had produced a Moon mission concept as early as the 1930s and went on to create the first fully realized design for an interstellar craft, Project Daedalus. The BIS used the 'red issues' of its journal to focus on interstellar work while JBIS was...
To Ride the Solar Wind
What we hope to learn from early experiments with the electric sail is whether keeping a steady electric potential on long tethers will give us enough interaction with the solar wind to make for viable propulsion. ESTCube-1, launched earlier this week, is a step in that direction. Even though it uses but a single 10-meter wire, its rotation rate should change once the tether is fully extended and powered up. Bear in mind that ESTCube-1 is deep within the Earth’s magnetosphere, so the charged particles it will be interacting with are not from the solar wind, but a proof of principle is sought here that could make electric sailing a candidate for outer system-bound spacecraft. It’s important to distinguish between solar sails and their electric counterparts. The Japanese IKAROS sail, successfully tested, showed that solar photons could impart momentum to a thin sail, as our experience with early satellites had already demonstrated. The beauty of sailing in any form is that we leave the...
Enter the Electric Sail
Some years back at the Aosta interstellar conference I had the pleasure of being on a bus making its way at night through the Italian alps with Pekka Janhunen sitting immediately in front of me. Janhunen (Finnish Meteorological Institute) is the developer of the electric sail concept soon to be tested by the ESTCube-1 satellite, which launched last night aboard a Vega rocket from the Kourou spaceport in French Guiana. Our group had been talking about interstellar issues all day at the conference and now, headed back to the hotel following a memorable dinner at high elevation, I was curious whether an electric sail had interstellar applications. The immediate answer seemed to be no, given that the highest velocities Janhunen had been talking about for the idea were about 100 kilometers per second, much faster than Voyager 1's 17 kilometers per second, but a long way short of what we would like to see on an interstellar flight. But the ever thoughtful Pekka pointed out to me that as a...
Update on Starship Century Symposium
We had a successful launch last night of the ESTCube-1 satellite from Kourou, about which more tomorrow when I'll be talking about electric sails and their uses both interplanetary and interstellar. But this morning, with the Starship Century Symposium rapidly approaching, I wanted to run this overview, which corrects and updates several things in the post I published a couple of weeks ago. Seats are still available for those of you in range. Thanks to Jim Benford for the following: The Starship Century Symposium is the inaugural event at the new Arthur C. Clarke Center for Human Imagination at UC San Diego, Tuesday Wednesday, May 21-22. The program is located here. The symposium celebrates the publication of the Benfords' anthology, Starship Century. Jon Lomberg, the artist who collaborated extensively with Carl Sagan, has read the book and has this comment: Starship Century is the definitive document of this moment in humanity's long climb to the stars. Here you can find the...
Robert Goddard’s Interstellar Migration
Astronautics pioneer Robert H. Goddard is usually thought of in connection with liquid fuel rockets. It was his test flight of such a rocket in March of 1926 that demonstrated a principle he had been working on since patenting two concepts for future engines, one a liquid fuel design, the other a staged rocket using solid fuels. "A Method of Reaching Extreme Altitudes," published in 1920, was a treatise published by the Smithsonian that developed the mathematics behind rocket flight, a report that discussed the possibility of a rocket reaching the Moon. While Goddard's work could be said to have anticipated many technologies subsequently developed by later engineers, the man was not without a visionary streak that went well beyond the near-term, expressing itself on at least one occasion on the subject of interstellar flight. Written in January of 1918, "The Ultimate Migration" was not a scientific paper but merely a set of notes, one that Goddard carefully tucked away from view, as...
Starship Musings: Warping to the Stars
by Kelvin F.Long The executive director of the Institute for Interstellar Studies here gives us his thoughts on Star Trek and the designing of starships, with special reference to Enrico Fermi. Kelvin is also Chief Editor for the Journal of the British Interplanetary Society, whose latest conference is coming up. You'll find a poster for the Philosophy of the Starship conference at the end of this post. Like many, I have been inspired and thrilled by the stories of Star Trek. The creation of Gene Roddenberry was a wonderful contribution to our society and culture. I recently came across an old book in the shop window of a store and purchased it straight away. The book was titled The Making of Star Trek, The book on how to write for TV!, by Stephen E.Whitfield and Gene Roddenberry. It was published by Ballantine books in 1968 - the same year that the Stanley Kubrick and Arthur C Clarke 2001: A Space Odyssey came out. What with all this and Project Apollo happening, the late 1960s was...
Stars for JWST
Red dwarfs or brown? The question relates to finding targets as the James Webb Space Telescope gets closer to launch. We're going to want to have a well defined target list so that the JWST can be put to work right away, and part of that effort means finding candidate planets the telescope can probe. Yesterday's white paper on a proposed search for brown dwarfs using the Spitzer Space Telescope lined up a number of reasons why these objects are good choices: * for a given planetary equilibrium temperature, the orbit gets shorter with decreasing primary mass, increasing the probability of transit and providing 50+ occultations per year (and 50+ transits); * the planet to brown dwarf size ratio means transiting rocky planets produce deep transits and permit the detection of planets down to Mars' size in a single transit event when using Spitzer; * the reliability of the detection is helped by the absence of known false astrophysical positives: brown dwarfs have very peculiar colors,...
Hunting for Brown Dwarf Planets
Brown dwarfs fascinate me because they're the newest addition to the celestial menagerie, exotic objects about which we know all too little. The evidence suggests that brown dwarfs can form planets, but so far we've found only a few. Two gravitational microlensing detections on low mass stars have been reported, one of which is a 3.2 Earth-mass object orbiting a primary with mass of 0.084 that of the Sun, putting it into the territory between brown dwarfs and stars. The MEarth project has uncovered a planet 6.6 times the mass of the Earth orbiting a 0.16 solar mass star. Now a new proposal to use the Spitzer Space Telescope to hunt for brown dwarfs planets is available on the Net, one that digs into what we've found so far, with reference to the discoveries I just mentioned: Accounting for their low probabilities, such detections indicate the presence of a large, mostly untapped, population of low mass planets around very low mass stars (see also Dressing & Charbonneau (2013))....
Starship Congress Registration Opens
Our friends at Icarus Interstellar continue working on this summer's conference. Just in from my son Miles is news about the opening of registration for the Dallas event. Registration for the 2013 Starship Congress, hosted by Icarus Interstellar, is now open. The registration fee is $100; however, the first 25 paid registrations receive a $25 discount. This discount is also available to individuals who sign up by May 2nd, 2013. Students can register for a reduced rate of $50. Students must present a valid student I.D. at the Starship Congress to take advantage of the student rate. The $25 discount does not apply to student registrations. Group rates are also available. An optional lunch is offered for August 15, 16 and 17 for $25. The Starship Congress will be held August 15-18 at the Hilton Anatole in Dallas, Texas. A discounted rate for Starship Congress attendees is available at the Hilton Anatole from August 12-20. To book a room at the special rate, click here. Richard Obousy,...
Robotic Replicators
Centauri Dreams regular Keith Cooper gives us a look at self-replication and the consequences of autonomous probes for intelligent cultures spreading into the universe. Is the Fermi paradox explained by the lack of such civilizations in the galaxy, or is there a far more subtle reason? Keith has been thinking about these matters for some time as editor of both Astronomy Now and Principium, which has just published its fourth issue in its role as the newsletter of the Institute for Interstellar Studies. Intelligent robotic probes, as it turns out, may be achievable sooner than we have thought. by Keith Cooper There's a folk tale that you'll sometimes hear told around the SETI or physics communities. Back in the 1940s and 50s, at the Los Alamos National Labs, where the first nuclear weapons were built, many physicists of Hungarian extraction worked. These included such luminaries in the field as Leó Szilárd, Eugene Wigner, Edward Teller and John Von Neumann. When in 1951 their...
The Alpha Centauri Angle
Apropos of yesterday's article on the discovery of Proxima Centauri, it's worth noting that Murray Leinster's story "Proxima Centauri," which ran in Astounding Stories in March of 1935, was published just seven years after H. A. Alden's parallax findings demonstrated beyond all doubt that Proxima was the closest star to the Sun, vindicating both Robert Innes and J. G. E. G. Voûte. Leinster's mile-wide starship makes the first interstellar crossing only to encounter a race of intelligent plants, the first science fiction story I know of to tackle the voyage to this star. The work surrounding Proxima Centauri was intensive, but another fast-moving star called Gamma Draconis in Draco, now known to be about 154 light years from Earth thanks to the precision measurements of the Hipparcos astrometry satellite, might have superseded it. About 70 percent more massive than the Sun, Gamma Draconis has an optical companion that may be an M-dwarf at about 1000 AU from the parent. Its bid for...
Finding Proxima Centauri
It's fascinating to realize how recent our knowledge of the nearest stars has emerged. A little less than a century has gone by since Proxima Centauri was discovered by one Robert Thorburn Ayton Innes (1861-1933), a Scot who had moved to Australia and went on to work at the Union Observatory in Johannesburg. Innes used a blink comparator to examine a photographic plate showing an area of 60 square degrees around Alpha Centauri, comparing a 1910 plate with one taken in 1915. Forty hours of painstaking study revealed a star with a proper motion similar to Alpha Centauri (4.87" per year), and about two degrees away from it. The question Innes faced was whether the new star was actually closer than Alpha Centauri, an issue that could be resolved only with better equipment. Ian Glass (South African Astronomical Observatory) tells the tale in a short paper written for the publication African Skies. Innes ordered a micrometer eyepiece that would be fitted to the observatory's 9-inch...
A Gravitationally Lensed Supernova?
I keep a close eye on gravitational lensing, not only because of the inherent fascination of the subject but also because the prospect of using the Sun’s own lensing to study distant astrophysical phenomena could lead to near-term missions to 550 AU and beyond. And because I’m also intrigued by ‘standard candles,’ those markers of celestial distance so important in the history of astronomy, I was drawn to a new paper on the apparent gravitational lensing of a Type Ia supernova (SNIa). This is the kind of supernova that led to the discovery of the accelerating expansion of the universe by giving us ways to measure the distance to these objects. The point about Type Ia supernovae is that they are so much alike. We may not fully understand the mechanisms behind their explosions, but we have overwhelming evidence that these supernovae reach nearly standard peak luminosities. There is also a strong correlation between their luminosity and other observables like the shapes of their...
Thoughts on Kepler 62 and Habitability
Because we only have direct images of a tiny number of planets orbiting other stars, we're used to extrapolating as much as we can from our data and plugging in possible scenarios. But as the recent announcement of two 'super-Earths' around Kepler 62 demonstrates, we're coming up hard against the limits of our knowledge. The comments on my recent story on the Kepler find bring up Greg Laughlin's always interesting systemic site and a post he made in early April. Laughlin (UC-Santa Cruz) is worth reading not only for his shrewd analysis but for the sheer brio he brings to the exoplanet hunt. And here he sounds a note of caution: I think we currently have substantially less understanding of the extrasolar planets than is generally assumed. Thousands of planets are known, but there is no strong evidence that any of them bear a particular resemblance to the planets within our own solar system. There's always a tendency, perfectly encapsulated by the discipline of astrobiology, with its...