Small Planets Confirm Kepler’s Capabilities

The planetary system around Kepler-37, some 210 light years from Earth in the constellation Lyra, had its place in the media spotlight yesterday, although it will surely be a brief one. But it's heartening to see the quickening interest in exoplanets that each new discovery brings. Will the interest continue? In the Apollo days, public enthusiasm reached a frenzy as we moved toward the first lunar landings, then plummeted. What the media see as the big event in exoplanetary science is the discovery of a terrestrial world around a star like the Sun. Let's hope there is no similar letdown afterwards. After all, we're getting close, and discoveries like those announced yesterday remind us that Kepler can find very small worlds indeed. Kepler-37b lays claim to being the smallest planet yet found around a star similar to the Sun, similar in this case meaning a G-class star with a radius about three-quarter's of the Sun's. The new planet is just a bit larger than our Moon, as the image...

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Resources Between the Stars

Yesterday we looked at the possibility of colonizing worlds much different from the Earth. Seen in one light, pushing out into the Kuiper Belt and building settlements there is part of a slow migration to the stars that may occur without necessarily being driven by that purpose. Seen in another, experimenting with human settlements in extreme environments is a way of exploiting the resources of nearby space, pushing the human presence out into the Oort Cloud. Either way, we can find places that, while not 'habitable' in the classic sense of liquid water at the surface, are nonetheless colonizable. In his Tale of Two Worlds, novelist Karl Schroeder works on a definition of a colonizable world. It has to have an accessible surface, for one thing, meaning one we can work with -- obviously a surface gravity of 4 g's is going to be a problem. Much smaller worlds like Pluto, as we saw yesterday in Ken Roy's work on possible colonies there, pose less of a challenge, as we can imagine...

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Interstellar Expansion: Colonizing Ice Dwarfs

Are habitable planets the best places to look for life? The question seems odd, because we're assuming life has to have clement conditions to emerge and survive. But step beyond the question of life's formation and the issue can be framed differently. Where beyond its birthplace might life migrate? In SETI terms, where might we look for the signature of a civilization advanced enough to move beyond its home world and expand between the stars? A lot of ideas seem to be converging here. In Huntsville, Ken Roy (whose description at the recent interstellar conference was 'an engineer living and working amidst the relics of the Manhattan Project in Oak Ridge, Tennessee') described potential habitats stretching far out into the Solar System and beyond. Roy has been working for some time with Robert Kennedy and David Fields on colonization scenarios. My own talk covered the kind of places where we might extract resources, ranging from icy dwarfs like Pluto to cometary objects and 'rogue'...

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Near-Misses and their Uses

We can hope that the celestial events of February 15, including the spectacular fireball over Chelyabinsk and the near-miss from asteroid 2012 DA14, have raised public consciousness about Earth's neighbors in space. And indeed, this seems to be the case. Media outlets were flooded with articles, photos and video, and talk show hosts found themselves asking what could be done to prevent future impacts. Could all of this prompt a new surge of interest in space? The scenario is exactly what Arthur C. Clarke wrote about in Rendezvous with Rama (1972), where what it takes for humanity to get serious about developing a protective system (and, by extension, about pushing its space program forward) is an impact. We can be grateful that the one we've just seen was far smaller than Clarke's, as described in the first chapter of the novel: At 0946 GMT on the morning of September 11 in the exceptionally beautiful summer of the year 2077, most of the inhabitants of Europe saw a dazzling fireball...

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Alpha Centauri Sunrise

If the title of this piece conjures up exotic images, that's all to the good. In fact, I'm surprised that "Alpha Centauri Sunrise" hasn't been the title of a science fiction story somewhere along the line, but a quick check shows no such reference. Thus when Robert Kennedy (The Ultimax Group) created a drink called the Alpha Centauri Sunrise at our recent conclave in Huntsville, he was breaking new ground. And maybe images of a double sunrise also came to mind, the view from an as yet undiscovered world where Centauri A is a bright flare in the morning sky while a still closer Centauri B begins to nudge up over the hills, flooding the scene with orange light. And what happened to Proxima Centauri? It would not be a factor in a scene like that, its light so dim that it would not stand out from other stars in a completely dark sky. Only its proper motion would alert local astronomers to how close it was (roughly 15000 AU). But let's drink to Proxima anyway. I promised the recipe for...

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The Draco Kill Shot

When I was in Huntsville for the recent interstellar conference, I noticed people walking around with black rubber wristbands that said ‘Build a Star Ship.’ Space educator Mike Mongo was handing these out to all concerned, and I soon picked one up to give my grandson. They’re an interesting form of marketing -- leave these in the right places and kids pick them up. Maybe it becomes a fad to wear them. The point is, you never know whose mind you might reach. And maybe once or twice, you give a wristband to a kid who starts dreaming about the stars, and pretty soon that leads to a course of study and then one day a career. The Roman historian Plutarch said it best: “The mind is not a vessel to be filled, but a fire to be ignited.” And when ignition occurs, it’s often a sudden, passionate event rather than a slow building of sequential ideas. It’s that fire that drives subsequent study and makes long hours amidst the databases and classrooms pay off in the form of eventual insights and...

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Cultural Diffusion and SETI

What happens to us if our SETI efforts pay off? Numerous scenarios come to mind, all of them speculative, but the range of responses shown in Carl Sagan's Contact may be something like the real outcome, with people of all descriptions reading into a distant message whatever they want to hear. Robert Lightfoot (South Georgia State College) decided to look at contact scenarios we know something more about, those that actually happened here on Earth. His presentation in Huntsville bore the title "Sorry, We Didn't Mean to Break Your Culture." Known as 'Sam' to his friends, Lightfoot is a big, friendly man with an anthropologist's eye for human nature. His talk made it clear that if we're going to plan for a possible SETI reception, we should look at what happens when widely separated groups come into contact. Cultural diffusion can happen in two ways, the first being prompted by the exchange of material objects. In the SETI case, however, the non-material diffusion of ideas is the most...

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Interstellar Studies: Surveying the Landscape

One of the things I love about writing Centauri Dreams is that I learn something new every day. Often this comes from the research needed for individual stories, but just as often it comes from readers suggesting new directions or seeing nuances in an earlier story that I had missed. Yesterday's post on long-term thinking led to an exchange with Centauri Dreams regular NS, who questioned my ideas on longevity in the Middle Ages, and before long we were both digging up data to try to discover what the numbers really are. It's an ongoing process, and if you're interested in such arcana, you can follow it in yesterday's comments thread. If you're just joining us and wondering why we're discussing medieval longevity, it ties into what I was saying about long-haul construction projects like cathedrals, and the question of what a worker on one of these projects might have thought of his chances of seeing its completion. You can also chalk it up to a fascination with the Middle Ages that...

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The Long Result

I conceived an early love for Tennyson, but it wasn't until a bit later in life that I ran into his "Locksley Hall," which contains lines many science fiction fans are familiar with: Many a night I saw the Pleiads, rising thro' the mellow shade, Glitter like a swarm of fire-flies tangled in a silver braid. Here about the beach I wander'd, nourishing a youth sublime With the fairy tales of science, and the long result of Time; When the centuries behind me like a fruitful land reposed; When I clung to all the present for the promise that it closed: When I dipt into the future far as human eye could see; Saw the Vision of the world and all the wonder that would be.— and so on. The poem is the lament of a soldier returning to the places of his boyhood and eventually turning his thoughts, and his resolve, on the future. When I read the line 'the long result of time,' I realized that it was here that I found resonance with the poet. The idea of a remote futurity and the need to build...

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Interstellar Flight: Adapting Humans for Space

It's surprising but gratifying that we can now talk about the 'interstellar community.' Just a few years back, there were many scientists and engineers studying the problems of starflight in their spare time, but when they met, it was at conferences dedicated to other subjects. The fact that the momentum has begun to grow is made clear by the explicitly interstellar conferences of recent memory, from the two 100 Year Starship symposia to the second Tennessee Valley Interstellar Workshop. Icarus Interstellar is mounting a conference this August in Dallas, and the Institute for Interstellar Studies plans its own gathering this fall in London. Of course the Internet is a big part of the picture -- Bob Forward and his colleagues could use the telephone and the postal service to keep in touch, but the energizing power of instant document exchange and online discussion was in the future. All this was apparent in Huntsville for the Tennessee Valley event, from which I have just returned....

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After Huntsville, a Red Dwarf Bonanza

Returning from Huntsville after the Tennessee Valley Interstellar Workshop, I was catching up on emails at the airport when the latest news about exoplanets and red dwarfs popped up on CNN. It was heartening to look around the Huntsville airport and see that people who had been reading or using their computers were all looking up at the screen and following the CNN story, which was no more than a thirty second summary. The interest in exoplanets is out there and may bode good things for public engagement in space matters. At least let’s hope so. The workshop was a great success, and congratulations are owed to Les Johnson, Robert Kennedy, Eric Hughes and the entire team that made this happen (a special nod to Martha Knowles and Yohon Lo!). This morning I want to focus on the exoplanet news as a way of getting back on schedule, but tomorrow I’ll start going through my notes and talking about the Huntsville gathering. I’m hoping to have several articles in coming weeks from...

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Tennessee Valley Interstellar Workshop

Air travel presents us with challenges we seldom anticipate. Flying into Charlotte on Sunday I had developed a ferocious headache. I was headed to the Tennessee Valley Interstellar Workshop in Huntsville and had a long enough layover in Charlotte to seek out a pain reliever with decongestant properties. The ridiculous thing was that I couldn't get the plastic mini-pack open. The little symbol showed me tearing off the corner of the packet, but it wouldn't tear for me, and it wouldn't tear for the guy who happened to be sitting next to me at the USAir gate. It became clear that I needed something sharp to get into this packet, but it was also clear that I was in an airport, the very definition of which these days is to prevent passengers from having anything sharp. I finally took the packet back to the kiosk I bought it from and demanded redress. The lady looked askance at me, looked at the packet, and opened it effortlessly. Further comment seems superfluous. By the time I got off...

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New Book Recalls “Men Into Space”

These days we know that perhaps a million objects the size of the Tunguska impactor or larger are moving through nearby space, and talk of how to deflect asteroids has become routine. Given our increasing awareness of near-Earth objects, it wouldn't be a surprise to hear of a new Hollywood treatment involving an Earth-threatening asteroid. But I wouldn't have expected a science fiction series that ran from 1959 to 1960 would have depicted an asteroid mission and the dangers such objects represent. Nonetheless, I give you "Asteroid," from the show Men Into Space, with script by Ted Sherdeman. Viewers on November 25, 1959 saw the show's protagonist Col. Edward McCauley (William Lundigan) take a crew to 'Skyra,' a 3.5-kilometer long rock that scientists believed might hit the Earth. The crew assesses whether the asteroid is salvageable for use as a space station and decides there is no other choice but to destroy Skyra, which they do at the cost of considerable suspense as McCauley...

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Habitable Zones: A Moving Target

Habitable zones are always easy enough to explain when you invoke the ‘Goldilocks’ principle, but every time I talk about these matters there’s always someone who wants to know how we can speak about places being ‘not too hot, not too cold, but just right.’ After all, we’re a sample of one, and why shouldn’t there be living creatures beneath icy ocean crusts or on worlds hotter than we could tolerate? I always point out that we have to work with what we know, that water and carbon-based life are what we’re likely to be able to detect, and that we need to fund the missions to find it. The last word on habitable zone models has for years been Kasting, Whitmire and Reynolds on “Habitable Zones around Main Sequence Stars.” Now Ravi Kopparapu (Penn State) has worked with Kasting and a team of researchers to tune-up the older model, giving us new boundaries based on more recent insights into how water and carbon dioxide absorb light. Both models work with well defined boundaries, the inner...

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TW Hydrae: An Infant Planetary System Analyzed

You have to like the attitude of Thomas Henning (Max-Planck-Institut für Astronomie). The scientist is a member of a team of astronomers whose recent work on planet formation around TW Hydrae was announced this afternoon. Their work used data from ESA's Herschel space observatory, which has the sensitivity at the needed wavelengths for scanning TW Hydrae's protoplanetary disk, along with the capability of taking spectra for the telltale molecules they were looking for. But getting observing time on a mission like Herschel is not easy and funding committees expect results, a fact that didn't daunt the researcher. Says Henning, "If there's no chance your project can fail, you're probably not doing very interesting science. TW Hydrae is a good example of how a calculated scientific gamble can pay off." I would guess the relevant powers that be are happy with this team's gamble. The situation is this: TW Hydrae is a young star of about 0.6 Solar masses some 176 light years away. The...

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Explaining Retrograde Orbits

While radial velocity and transit methods seem to get most of the headlines in exoplanet work, there are times when direct imaging can clarify things found by the other techniques. A case in point is the HAT-P-7 planetary system some 1000 light years from Earth in the constellation Cygnus. HAT-P-7b was interesting enough to begin with given its retrograde orbit around the primary (meaning its orbit was opposite to the spin of its star). Learning how a planet can emerge in a retrograde orbit demands learning more about the system at large, which is why scientists from the University of Tokyo began taking high contrast images of the HAT-P-7 system. It had been Norio Narita (National Astronomical Observatory of Japan) who, in 2008, discovered evidence of HAT-P-7b’s retrograde orbit. Narita’s team has now used adaptive optics at the Subaru Telescope to measure the proper motion of what turns out to be a small companion star now designated HAT-P-7B. The team was also able to confirm a...

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Data Storage: The DNA Option

One of the benefits of constantly proliferating information is that we're getting better and better at storing lots of stuff in small spaces. I love the fact that when I travel, I can carry hundreds of books with me on my Kindle, and to those who say you can only read one book at a time, I respond that I like the choice of books always at hand, and the ability to keep key reference sources in my briefcase. Try lugging Webster's 3rd New International Dictionary around with you and you'll see why putting it on a Palm III was so delightful about a decade ago. There is, alas, no Kindle or Nook version. Did I say information was proliferating? Dave Turek, a designer of supercomputers for IBM (world chess champion Deep Blue is among his creations) wrote last May that from the beginning of recorded time until 2003, humans had created five billion gigabytes of information (five exabytes). In 2011, that amount of information was being created every two days. Turek's article says that by 2013,...

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The Velocity of Thought

How fast we go affects how we perceive time. That lesson was implicit in the mathematics of Special Relativity, but at the speed most of us live our lives, easily describable in Newtonian terms, we could hardly recognize it. Get going at a substantial percentage of the speed of light, though, and everything changes. The occupants of a starship moving at close to 90 percent of the speed of light age at half the rate of their counterparts back on Earth. Push them up to 99.999 percent of c and 223 years go by on Earth for every year they experience. Thus the 'twin paradox,' where the starfaring member of the family returns considerably younger than the sibling left behind. Carl Sagan played around with the numbers in the 1960s to show that a spacecraft moving at an acceleration of one g would be able to reach the center of the galaxy in 21 years (ship-time), while tens of thousands of years passed on Earth. Indeed, keep the acceleration constant and our crew can reach the Andromeda...

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Talking Back from Alpha Centauri

Back when I was working on my Centauri Dreams book, JPL's James Lesh told me that the right way to do communications from Alpha Centauri was to use a laser. The problem is simple enough: Radio signals fall off in intensity with the square of their distance, so that a spacecraft twice as far from Earth as another sends back a signal with four times less the strength. Translate that into deep space terms and you've got a problem. Voyager puts out a 23-watt signal that has now spread to over one thousand times the diameter of the Earth. And we're talking about a signal 20 billion times less powerful than the power to run a digital wristwatch. Now imagine being in Alpha Centauri space and radiating back a radio signal that is 81,000,000 times weaker than what Voyager 2 sent back from Neptune. But lasers can help in a major way. Dispersion of the signal is negligible compared to radio, and optical signals can carry more information. Lesh is not a propulsion man so he leaves the problem of...

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Deep Space Industries: Mining Near-Earth Asteroids

Deep Space Industries is announcing today that it will be engaged in asteroid prospecting through a fleet of small 'Firefly' spacecraft based on cubesat technologies, cutting the costs still further by launching in combination with communications satellites. The idea is to explore the small asteroids that come close to Earth, which exist in large numbers indeed. JPL analysts have concluded that as many as 100,000 Near Earth Objects larger than the Tunguska impactor (some 30 meters wide) are to be found, with roughly 7000 identified so far. So there's no shortage of targets (see Greg Matloff's Deflecting Asteroids in IEEE Spectrum for more on this. 'Smaller, cheaper, faster' is a one-time NASA mantra that DSI is now resurrecting through its Firefly spacecraft, each of which masses about 25 kilograms and takes advantages of advances in computing and miniaturization. In its initial announcement, company chairman Rick Tumlinson talked about a production line of Fireflies ready for action...

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Charter

In Centauri Dreams, Paul Gilster looks at peer-reviewed research on deep space exploration, with an eye toward interstellar possibilities. For many years this site coordinated its efforts with the Tau Zero Foundation. It now serves as an independent forum for deep space news and ideas. In the logo above, the leftmost star is Alpha Centauri, a triple system closer than any other star, and a primary target for early interstellar probes. To its right is Beta Centauri (not a part of the Alpha Centauri system), with Beta, Gamma, Delta and Epsilon Crucis, stars in the Southern Cross, visible at the far right (image courtesy of Marco Lorenzi).

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