If you've been following the Breakthrough Starshot concept in these pages and elsewhere, you'll know that it's small at one end and big on the other. A beamed sail mission, it would use sails four meters to the side -- quite small by reference to earlier beamed sail designs -- driven by a massive phased laser array on the Earth. The array is projected to be a kilometer to the side, incorporating laser emitters working in perfect synchronization to produce what Pete Worden, formerly of NASA Ames, described in Palo Alto as "a laser wind of 50 gigawatts." Worden is now executive director of Breakthrough Starshot. As with the sail, so with the payload. We have no macro-scale spacecraft here but a 'Starchip' about the size of a postage stamp, making it a kind of futuristic smartphone containing not just cameras, communication equipment and navigation instruments but tiny thrusters. If you want to imagine something like this, you take trends in digital technology like Moore's Law and...

When you don't have the technology to get to an interesting place like the Oort Cloud, it's more than a little helpful when nature brings an Oort Cloud object to you. At least we think that the object known as C/2014 S3 (Pan-STARRS) has moved into the warmer regions of the Solar System from the Oort. A gravitational nudge in that distant region would be all it took to send the object, with an orbital period now estimated to be 860 years, closer to the Sun. And here things get interesting, because C/2014 S3 is the first object discovered on a long-period cometary orbit that shows all the spectral characteristics of an inner system asteroid. The level of activity on the object, apparently the result of sublimation of water ice, is five to six orders of magnitude lower than what we would expect from an active long-period comet at a similar distance from the Sun. Karen Meech (University of Hawaii) and colleagues believe that the object formed in the inner system at about the same time as...

Some of you may recall an episode of Star Trek: The Next Generation in which the inhabitants of a planet called Aldea use a planetary defense system that includes a cloaking device. The episode, “When the Bough Breaks,” at one point shows the view from the Enterprise’s screens as the entire planet swims into view. My vague recollection of that show was triggered by the paper we looked at yesterday, in which David Kipping and Alex Teachey discuss transit light curves and the ability of a civilization to alter them. After all, if an extraterrestrial culture would prefer not to be seen, a natural thought would be to conceal its transits from worlds that should be able to detect them along the plane of the ecliptic. Light curves could be manipulated by lasers, and as we saw yesterday, the method could serve either to enhance a transit, thus creating a form of METI signaling, or to conceal one. In the latter case, the civilization would want to create a change in brightness that would...

J. G. Ballard (1930-2009) emerged as one of the leading figures in 20th Century science fiction. His fascination with inner as opposed to 'outer' space infused his characters and landscapes with a touch of the surreal, taking the fiction of the space age into deeply psychological realms. Christopher Phoenix here looks at the question of centuries-long journeys to the stars, with reference to a Ballard story in which a crew copes with isolation on what appears to be an interstellar mission. What we learn about ship and crew informs the broader discussion: If it takes more than a single generation to make an interstellar crossing, what can we do to keep our crew functional? And is there such a thing as happiness under these constraints? By Christopher Phoenix A few months back, Centauri Dreams ran Gregory Benford's review of Kim Stanley Robinson's novel Aurora. After reading that review and the discussion that followed, I began thinking about fiction that explores how starflight might...

"No matter how these issues are ultimately resolved, Centauri Dreams opts for the notion that even the back of a cereal box may contain its share of mysteries." I wrote that line in 2005, and if it sounds cryptic, read on to discover its origins, ably described by Christopher Phoenix. I first encountered Christopher in an online discussion group made up of physicists and science fiction writers, where his knack for taking a topic apart always impressed me. A writer whose interest in interstellar flight is lifelong, he is currently turning his love of science fiction into a novel that, he tells me "incorporates some of the ideas we talk about on Centauri Dreams as a background setting." Today's essay examines the ideas of a physicist who dismissed the idea of interstellar flight entirely, while using a set of assumptions Christopher has come to challenge. by Christopher Phoenix "All this stuff about traveling around the universe in space suits -- except for local exploration which I...

I'm on the road and don't have a lot of time for writing, but I want to go ahead and get these new Pluto images up. They're now available on the NASA site, and were introduced at the news conference at JHU/APL that just concluded. I'll also quote just a bit of the news release for each photo. New close-up images of a region near Pluto's equator reveal a giant surprise: a range of youthful mountains rising as high as 11,000 feet (3,500 meters) above the surface of the icy body. The mountains likely formed no more than 100 million years ago -- mere youngsters relative to the 4.56-billion-year age of the solar system -- and may still be in the process of building, says Jeff Moore of New Horizons' Geology, Geophysics and Imaging Team (GGI). That suggests the close-up region, which covers less than one percent of Pluto's surface, may still be geologically active today. This one I mis-typed in my Twitter coverage for those who were following it, but the correct number is 100 million years....

While both Alan Stern and Glen Fountain admitted to having anxious moments over the weekend when New Horizons went silent, it became clear at yesterday's news conference that those moments were short and quickly subsumed with ongoing duties. Stern is principal investigator for New Horizons, and the man most closely identified with making the mission a reality, while Fountain is project manager for New Horizons at JHU/APL in Maryland. It was Stern who pointed out that the spacecraft has been in safe mode a number of times already. Nine times, as a matter of fact, since launch, although as of yesterday we are back in the realm of normal operations. So the circumstances were not unfamiliar even if this safe mode came so close to destination that it raised inevitable concern and a flutter of worry on Twitter. Stern said he was in the control center six or seven minutes after getting the call that something was wrong. It also turns out that this was the first safe mode occurrence in which...

Centauri Dreams regular James Jason Wentworth wrote recently with some musings about Bracewell probes, proposed by Ronald Bracewell in a 1960 paper. Bracewell conceived the idea of autonomous craft that could monitor developments in a distant solar system, perhaps communicating with any local species that developed technology. Pondering how such a craft might manage station-keeping over the aeons, Jason hit on the idea of using a natural effect that would draw little attention to itself, one he explains below. An amateur astronomer and interstellar travel enthusiast who worked at the Miami Space Transit Planetarium and volunteered at the Weintraub Observatory atop the adjacent Miami Museum of Science, Jason now makes his home in Fairbanks (AK). He was the historian for the Poker Flat Research Range sounding rocket launch facility near Fairbanks. His space history and advocacy articles have appeared in Quest: The History of Spaceflight magazine and Space News. by James Jason Wentworth...

Lunar Mission One is an interesting private attempt to put a payload on the lunar surface, a crowdsourced project aimed at doing good science and deepening public participation in spaceflight. Remembering the Apollo days, I'm always interested in seeing what can be done to renew interest in space, and having the chance to make a contribution toward such a self-starting space mission is undeniably attractive. As witness Lunar Mission One's pitch on Kickstarter, which has aimed for an ambitious £600,000 and has already raised £520,341. That figure is as of this morning, with five days to go in the attempt, and it's clear enough that £600,000 won't buy a lunar mission of considerable complexity, as this one is. But it's enough to take an effort that has been seven years in the building to the next level, which means establishment of working management teams and the beginning of procurement planning and risk assessment. That turns what has been a part-time volunteer project into a...

Some final thoughts on hybrid propulsion will wrap up this series on solar sails, which grew out of ideas I encountered in the new edition of the Matloff, Johnson and Vulpetti book Solar Sails: A Novel Approach to Interplanetary Travel (Copernicus, 2014). The chance to preview the book (publication is slated for later this month) took me in directions I hadn't anticipated. Solar Sails offers a broad popular treatment of all the sail categories and their history, as you'd expect, but this time through I focused on its four technical chapters on sail theory that helped me review the details. And because I kept running into the idea of multiple modes of propulsion, my thoughts on avoiding doctrinaire solutions continue to grow. In fact, I'd venture to say that probing into the possibilities of multimodal propulsion may offer a serious opportunity for insights. Centauri Dreams regular Alex Tolley came up with one of these yesterday, asking whether a sail mission to Jupiter space might...

What can we do to make telescopes better both on Earth and in space? Ashley Baldwin has some thoughts on the matter, with reference to a new paper that explores interferometry and advocates an approach that can drastically improve its uses at optical wavelengths. Baldwin, a regular Centauri Dreams commenter, is a consultant psychiatrist at the 5 Boroughs Partnership NHS Trust in Warrington, UK and a former lecturer at Liverpool and Manchester Universities. He is also a seriously equipped amateur astronomer -- one who lives a tempting 30 minutes from the Jodrell Bank radio telescope -- with a keen interest in astrophysics and astronomical imaging. His extensive reading takes in the latest papers describing optical breakthroughs, making him a key information source on these matters. His latest find could have major ramifications for exoplanet detection and characterization. by Ashley Baldwin An innocuous looking article by Michael J. Ireland (Australian National University, Canberra)...

I've mentioned before the irony that we may discover signs of robust extraterrestrial life sooner around a distant exoplanet than right here in our own Solar System. The scenario isn't terribly implausible: Perhaps we come up empty on Mars, or find ourselves bogged down with ambiguous results. As our rovers dig, we still have Europa, Enceladus and other outer system possibilities, but probably face a wait of decades before we could build and fly the missions needed to identify life. Meanwhile, the exoplanet hunt continues. While we've had many a setback -- the Space Interferometry Mission will always stand out in this regard, not to mention the inability to follow through with Terrestrial Planet Finder, Darwin and other high-end concepts -- it's just possible that within the next few decades, a space-based observatory will detect a solid biosignature from an exoplanet's atmosphere. Even the James Webb Space Telescope should be able to detect the transmission spectrum of an...

Adam Crowl first appeared in Centauri Dreams not long after I opened the site to comments about nine years ago. His insights immediately caught my eye and challenged my thinking. I have always admired auto-didacts, and Adam is an outstanding example: "I don't work in this field nor did I especially train in it," he writes. "I did physics/maths/engineering study but my astrophysics, astrodynamics, planetology and interstellar propulsion knowledge is self-taught." The list of books in the various disciplines -- as well as science fiction -- by which he did this will, I hope, become a future Centauri Dreams article. Adam writes the Crowlspace blog, is active in Project Icarus, the re-design of the 1970's Project Daedalus fusion starship now in progress at Icarus Interstellar, and is a frequent participant on this site, often pointing me to papers I would otherwise have missed. The one he discusses today is, typically for Adam, a true mind-bender. by Adam Crowl The long-term fate of Life...

We have another 'habitable zone' planet to talk about today, one not much bigger than the Earth, but it's probably also time to renew the caveat that using the word 'habitable' carries with it no guarantees. The working definition of habitable zone right now is that orbital distance within which liquid water might exist on the surface of a planet. Whether it actually does is just one of the questions. A second is whether or not we're in fact dealing with a rocky terrestrial world. So Centauri Dreams approaches the announcement of Kepler-186f with guarded enthusiasm for an exoplanet that looks interesting indeed. Five planets circle this star, an M-dwarf a great deal smaller and cooler than the Sun. Discovered by the Kepler space observatory, the planet presents us with transit information telling us that it is about 1.1 Earth radii, although we don't yet know what the mass of this world is, and hence can't make a definitive call on whether or not it is rocky. But Stephen Kane (San...

Reading Charles Adler's Wizards, Aliens and Starships over the weekend, I've been thinking about starflight and cost. Subtitled 'Physics and Math in Fantasy and Science Fiction,' Adler's book uses the genres as a way into sound science, and his chapters contain numerous references to writers like Poul Anderson, Larry Niven and Robert Heinlein. On the matter of speculative propulsion systems, he lingers over fusion and describes the work of Project Daedalus back in the 1970s, when an ad hoc team of volunteer scientists and engineers put together a serious starship study. Like the vessels written about in the science fiction of that era and before, Daedalus was simply a mammoth craft -- 53 million kilograms! -- but that corresponded with what SF had been telling us all along. We would travel to the stars aboard vessels not so different from ocean liners, perhaps big enough to be livable on a daily basis, or at least big enough to pack thousands of humans into cryogenic containers for a...

Most Centauri Dreams readers are hardly going to be surprised by the idea that a large number of objects exist well outside the orbit of Pluto and, indeed, outside the Kuiper Belt itself. The search for unknown planets or even a brown dwarf that might perturb cometary orbits in the Oort Cloud has occupied us for some time, with the latest analysis of WISE findings showing that nothing larger than Jupiter exists out to a distance of 26,000 AU. Objects of Saturn size or larger are ruled out within 10,000 AU, according to the work of Kevin Luhman (Penn State) and team, whose study probed deeply into the Wide-field Infrared Survey Explorer's results. For more on all this, see WISE: New Stars and Brown Dwarfs. But the evidence for objects big enough to perturb the local neighborhood does persist, even if we have to scale down our expectations as to its size. A new paper in Nature reports the discovery of 2012 VP113, a dwarf planet that joins Sedna in orbiting entirely beyond the Kuiper...

Yesterday I wrote about what Michael Michaud calls 'the new cosmic humanism,' looking back at an essay the writer and diplomat wrote for Interdisciplinary Science Reviews in 1979. Intelligence, Michaud believes, creates the opportunity to reverse entropy at least on the local scale, and to impose choice on a universe whose purpose we do not otherwise understand. Continuing growth into space, expansion and discovery are the kind of long-term goals humans can share, highlighting the extension of knowledge and the rediversification of our species. What Michaud is talking about is nothing less than a mission statement for extraterrestrial man, one that trades off a key uncertainty: In the face of an indifferent universe, intelligence itself may prove to be an evolutionary quirk that is of little consequence. Whether or not this is the case could depend on the decisions and purposeful choices of intelligent beings, assuming they choose to expand into the cosmos. Let me quote Michaud on...

An assistant professor of astronomy and astrophysics at Penn State, Jason Wright is well known to the Centauri Dreams community because of his continuing work on the search for extraterrestrial intelligence through detection of its waste heat rather than directed communication. The discipline widely known as Dysonian SETI is receiving more and more attention, and given Dr. Wright’s prominence in the field, I was delighted to receive the essay below, which offers background on the subject at large and an overview of his current project. Dr. Wright is a member of the Center for Exoplanets and Habitable Worlds and the Penn State Astrobiology Research Center (part of the NASA Astrobiology Institute), as well as being a member of the California Planet Survey consortium. His AstroWright blog is essential reading for anyone interested in SETI and the process of science at work. He also maintains the Exoplanet Orbit Database and Exoplanet Data Explorer at exoplanets.org. by Jason T. Wright...

Search for one thing and you may run into something just as interesting in another direction. That has been true in the study of exoplanets for some time now, where surprises are the order of the day. Today David Kipping (Harvard-Smithsonian Center for Astrophysics) addressed the 223rd meeting of the American Astronomical Society in Washington to reveal a planetary discovery made during the course of a hunt for exomoons, satellites of planets around other stars. Kipping's team has uncovered the first Earth-mass planet that transits its host star. Just how that happened is a tale in itself. Kipping heads up the Hunt for Exomoons with Kepler project, which mines the Kepler data looking for tiny but characteristic signatures. Transit timing variations are the key here, for a planet with a large moon may show telltale changes in its transits that point to the presence of the orbiting body. In the case of the red dwarf KOI-314, it became clear Kepler was seeing two planets repeatedly...

When technologies converge from rapidly fermenting disciplines like biology, information science and nanotech, the results become hard to predict. Singularities can emerge that create outcomes we cannot always anticipate. Rachel Armstrong explores this phenomenon in today's essay, a look at emerging meta-technologies that are themselves life-like in their workings. The prospects for new forms of design in our living spaces, including future spacecraft environments, are profound, as ongoing work in various venues shows. Dr. Armstrong, a regular Centauri Dreams contributor, explores these issues through her work at AVATAR (Advanced Virtual and Technological Architectural Research) at the University of Greenwich, London. by Rachel Armstrong Three lumps of muck hit the breathing membrane. A scattering of fragments blew back at the boys as they shattered like crumbs. 'You're right! They disappeared!' crowed the smallest of the trio. 'That building literally - ate dirt!' Despite its lumpy...