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British Interplanetary Society: Then and Now

by Paul Gilster | Feb 25, 2011 | Culture and Society | 30 Comments

by Kelvin Long Physicist and aerospace engineer Kelvin Long is the co-founder of Project Icarus, the interstellar design study that is a successor to Project Daedalus. Here he gives us a look at the history of the British Interplanetary Society, whose accomplishments and continuing efforts in the area of interstellar propulsion have energized the entire field. As well as being an active Tau Zero practitioner, Long is a fellow of the BIS and a member of the recently reconstituted BIS Technical Committee, and the Assistant Editor of the Journal of the British Interplanetary Society. More about the history of the BIS can be read in the BIS publication 'Interplanetary' written by the current President Bob Parkinson, which is now available from the society's Web site. The British Interplanetary Society (BIS) is a name synonymous with interstellar travel throughout its history. First formed by Philip E. Cleator in Liverpool in 1933, the organization's headquarters were subsequently moved...

Ongoing Planet Formation in the Chamaeleon?

by Paul Gilster | Feb 24, 2011 | Deep Sky Astronomy & Telescopes | 0 Comments

We recently looked at protoplanetary disks around the stars AB Aur and LkCa 15, new studies using adaptive optics at the Subaru telescope on Mauna Kea. Today we learn about another interesting disk, this one around the young star T Chamaeleontis (T Cha), about 350 light years from Earth in the southern constellation called the Chamaeleon. The star is a scant seven million years old and, as was the case with the Subaru studies, we've gained evidence for planet formation within the disk. The latest work, performed with the European Southern Observatory's Very Large Telescope, has delivered powerful evidence for a small companion. Brown dwarf or planet? At this point, we don't know. T Cha is a T Tauri star, meaning it is young, luminous and too cool for hydrogen fusion to operate. Instead, the star is powered by energy released as it contracts for the tens of millions of years it will take to reach the main sequence. The Very Large Telescope used adaptive optics technology and a...

An Internet Designed for Space

by Paul Gilster | Feb 23, 2011 | Communications and Navigation | 2 Comments

You would think that Internet pioneer Vint Cerf would be too busy with the upcoming transition from Internet Protocol version 4 to IPv6 -- not to mention his other duties as Google's Chief Internet Evangelist -- to keep an eye on space communications. But the man behind the Net's TCP/IP protocols never lets the human future off-planet get too far from his thoughts. These days the long hours he has already spent on developing a new methodology that lets us network not just Earth-based PCs but far-flung spacecraft have begun to pay off. 2011 should be a banner year for what many have already begun to call the InterPlanetary Internet. At issue is a key problem with the way the Internet works. TCP/IP stands for Transmission Control Protocol/Internet Protocol, and it describes a method by which data are broken into small data envelopes and labeled for routing through the network. When they reach their destination, the packets are then reassembled. We know how the Net that grew out of...

Hitting the Exoplanet Jackpot

by Paul Gilster | Feb 22, 2011 | Exoplanetary Science | 26 Comments

If by any chance you missed Lee Billings' recent work on BoingBoing, let me direct you to Cosmic Commodities: How Much is a New Planet Worth? Lee has been talking to planet hunter Greg Laughlin (UC-Santa Cruz) about the latter's equation that quantifies the worth of a given planet. It's an ingenious concept, one that accepts inputs like planetary mass, estimated temperature, type and brightness of the primary star, and generates a value in cash. Why do this? It's a way to measure the potential of an exoplanet to be interesting. or in Laughlin's terms, "a way for me to be able to quantify how excited I should be about any particular planet." Reasons to Go You can follow the genial and long-running musings on planetary value on Laughlin's systemic blog, but read Billings if you're not already familiar with the equation, because his interview with Laughlin walks you through all the parameters step by step. One of the interesting things about the equation is that the brighter the star...

A Gas Giant in the Oort Cloud?

by Paul Gilster | Feb 21, 2011 | Outer Solar System | 18 Comments

Of all the interesting targets the WISE (Wide-Field Infrared Explorer) mission might find, I've focused primarily on two in Centauri Dreams: A small star, doubtless a brown dwarf, that might be found closer to us than the Alpha Centauri trio, and a large planet out in the Oort Cloud that might be disturbing cometary orbits. That latter scenario turned up again last March in Finding the Real Planet X, when we looked at various theories about large objects in the outer system, including the thinking of John Matese and Daniel Whitmire (University of Louisiana at Lafayette). Parameters of a Perturber Matese has studied the possibility of small stars near our Sun for two decades, but his view now, as revealed in a paper just published in Icarus, is that an object three to five times larger than Jupiter may be the perturber we're looking for. Matese and Whitmire's paper on the matter has been available as a preprint since April, but its publication in Icarus has caught the eye of the...

Water, Water, Everywhere

by Paul Gilster | Feb 18, 2011 | Outer Solar System | 20 Comments

Our view of the Solar System has changed utterly in the last fifty years. Mention that at a cocktail party and your listener will assume you're talking about Pluto, the demotion of which has stirred more response than any other recent planetary news. But in addition to all we've learned through our spacecraft, our view of the Solar System has gone from a small number of orbiting planets to huge numbers of objects at vast distances. Fifty years ago, a Kuiper Belt many times more massive than the main asteroid belt was only theory. And the early Solar System models I grew up with never included any representation of a vast cloud of comets all the way out to 50,000 AU. We've also begun to learn that liquid water, once thought confined to the Earth, may be plentiful throughout the system. Caleb Scharf goes to work on this in a recent post in Life Unbounded, noting what our models are telling us about internal oceans on a variety of objects: Much can be done with purely theoretical models...

New Images of Planet-Forming Disks

by Paul Gilster | Feb 17, 2011 | Exoplanetary Science | 8 Comments

Protoplanetary disks present huge challenges, but we need to learn more about them to make sense of our exoplanet catalog. We're interested in learning about the two primary theories of planet formation -- core accretion from colliding bodies of rock or ice and gravitational instability in the disks themselves. But protoplanetary disks are dim compared to their central star, and our studies thus far have been more or less limited to the outer envelope of the disk structure. What that means is that we're looking at a scale that's much larger than our own Solar System, not sufficient for the kind of detailed observation we'd like to make. Fortunately, we have technologies like coronagraphs, that can mask the bright light of the central star, and adaptive optics that can compensate for the blurring effects of the Earth's atmosphere. Now we have new images from the Subaru telescope in Hawaii, which is using advanced versions of both technologies in an instrument called HiCIAO (High...

A Dialogue on SETI

by Paul Gilster | Feb 16, 2011 | Astrobiology and SETI | 58 Comments

Last October, a conference at the Royal Society looked into "the detection of life, the communication with potential extra-terrestrial civilizations, the implications for the future of humanity, and the political processes that are required." It was a fascinating gathering, one whose results I've been able to study ever since thanks to Keith Cooper, who forwarded videos of a debate there on interstellar messaging (METI) and passed along transcripts of the various panels. Keith is editor of the superb Astronomy Now and is an accomplished writer on space exploration and astronomy, with over 100 articles published. I especially want to mention SETI: Cosmic Call and SETI: Terminating the Transmission in relation to what follows below. For as Keith and I discussed these issues, it occurred to me that our correspondence in the form of a dialogue was a natural for Centauri Dreams. So here's a slightly edited version of some recent thoughts of ours on SETI, the strength of extraterrestrial...

Tempel 1: Close Pass, Delayed Images

by Paul Gilster | Feb 15, 2011 | Asteroid and Comet Deflection | 8 Comments

We're starting to get a look at imagery from the Stardust spacecraft's close approach to comet Tempel 1, which occurred this morning at about 0439 UTC (2339 EST). The mission is an extension for the comet-chasing spacecraft, which flew past comet Wild 2 in 2004 and collected samples from the cometary coma that were subsequently returned to Earth. This time we're returning to a previously visited comet, the site of the Deep Impact spacecraft's encounter in 2005. You'll recall that on that mission, an impactor was driven into the comet. Scientists are interested in learning what changes have occurred in the interval between visits, and possibly examining the crater. Image: NASA's Stardust-NExT mission transmitted the first image it took during its approach to comet Tempel 1 at 8:35 p.m. PST (11:35 p.m. EST) on Feb. 14, 2011, from a distance of approximately 2,462 kilometers (1,530 miles). The comet was first visited by NASA's Deep Impact mission in 2005. Credit:...

Space Technology Research Fellowships

by Paul Gilster | Feb 15, 2011 | Culture and Society | 0 Comments

Students interested in getting involved in space research should be aware of NASA's Space Technology Research Fellowships. The agency is currently seeking applications from graduate students at accredited US universities for the fellowships, with a deadline for submitting fellowship proposals of 23 February. The fellowships, which are sponsored by NASA's Office of the Chief Technologist, are available to US graduate student researchers who show 'significant potential to contribute to NASA's strategic space technology objectives through their studies.' NASA Chief Technologist Bobby Braun describes the program: "Our Space Technology Graduate Fellowships will help create the pool of highly skilled workers needed for NASA's and our nation's technological future, motivating many of the country's best young minds into educational programs and careers in science, technology, engineering and mathematics. This fellowship program is coupled to a larger, national research and development effort...

Toward an Interstellar Bibliography

by Paul Gilster | Feb 14, 2011 | Research Tools | 16 Comments

Back when I was first thinking about writing a book on interstellar flight, my reading began with Adrian Berry's fine study The Giant Leap: Mankind Heads for the Stars. A science writer and novelist, Berry was science correspondent for The Daily Telegraph from 1977 to 1997, and is now the paper's Consulting Editor (Science). The Giant Leap ranged through the various propulsion options and explained the history of the interstellar idea, but I found it more inspiring still in its expression of human motivations and the urge to explore. Looking at our human history of migration and exploration, Berry liked in particular the parallel between the settlement of the Polynesian islands and our future among the stars: It is the 'radiative' nature of the Polynesian voyages that provides the closest parallel to interstellar travel. It was all made possible by that forerunner of a starship, the double canoe. Imagine twin hulls about nine metres in length, covered by a single deck and a lateen...

Seeing Into the Jovian Clouds

by Paul Gilster | Feb 11, 2011 | Outer Solar System | 1 Comment

Adaptive optics changes everything for ground-based telescopes, removing the worst of the distortion caused by a changeable atmosphere and allowing astronomers to see objects with a clarity akin to a space-based platform. But the recent adaptive optics work at the Keck II telescope in Hawaii really put the technology to the test. Normally, astronomers use a laser to create an artificial 'star' that computers can monitor, using information about atmospheric conditions and distortions to adjust the telescope up to 2000 times per second. But if Jupiter is your target, you've got a problem. The giant planet is bright enough to obscure the laser 'star,' meaning you need a guide star that is brighter still and close to Jupiter to do the work. Europa turned out to be the target of choice, positioned perfectly on November 30, 2010 to allow the adaptive optics system to work and to allow the capture of the image below. What you're seeing is Jupiter in infrared light at a wavelength of nearly...

A Living Planet Between the Stars?

by Paul Gilster | Feb 10, 2011 | Astrobiology and SETI | 18 Comments

A planet that wanders through the night far from any star is a fascinating notion, one that resonates on some primal level with me because of my childhood viewing of the 1951 film The Man from Planet X. In the movie, a scientist on a remote Scottish moor observes a rogue planet as it approaches the Earth, and deals with a visitor from that world whose apparent good intentions are brought to ruin by a self-serving character intent on exploiting the situation. I doubt similar viewing of this old classic motivated many of my readers, but evidently the idea of a rogue planet does inspire thought, given how many people wrote me about new work on the idea of wandering planets. The paper is by Dorian Schuyler Abbot and Eric Switzer (University of Chicago) and follows up studies of similar ‘dark’ planets by John Debes (Carnegie Institution) and Steinn Sigurðsson (Penn State) -- more about the latter duo in a moment. For now, focus on the process. We know that planets can be thrown out of...

The ‘I Love Lucy’ Signal

by Paul Gilster | Feb 9, 2011 | Astrobiology and SETI | 28 Comments

As a fan of I Love Lucy since childhood, I've always been pleased that this show -- and not, say, Milton Berle or Sid Caesar -- is the one always referred to when talking about Earth being detected by other civilizations. And when I first thought about it, the idea that there was a detectable bubble of TV transmission forging out into the galaxy since Lucy's first show in 1951 seemed completely wondrous. I Love Lucy is 60 light years from us now, or will be with this October's anniversary of that first show. I've always wondered what extraterrestrials would make of Fred Mertz. The film Contact mines the theme of stray transmissions from Earth, although in the case of Sagan's story, it's the transmissions from the 1936 Olympics in Berlin that trigger the detection and subsequent transmissions to Earth. A writer and music critic who I've known over the years once asked me about the expanding wavefront of Earthly transmissions, pondering how marvelous it would be to somehow get out in...

Exoplanets: Answering the Big Questions

by Paul Gilster | Feb 8, 2011 | Exoplanetary Science | 10 Comments

When Geoff Marcy (UC-Berkeley) got started in the exoplanet game, it was the result of an apparent dead-end. As Marcy tells Wired.com in a recent interview, he had been working as a post-doc at the Carnegie Institute of Washington, feeling 'a little bit like an impostor' and wondering whether a career in science hadn't been a bad choice. But epiphanies happen in the strangest places. One afternoon he was taking a shower in Pasadena, and the rest is history: "So I thought, what do I care about? I would love to know if there were other planets around other stars. "This was a question that nobody was asking. It was 1983, and nobody was even talking about planets. Even our own solar system was considered boring at the time. "So by the time I turned off the shower, I knew how I was going to end my career. I quickly realized that this was kind of a lucky moment. By knowing that I was a failure, I was free. I could just satisfy myself, and hunt for planets — even though it was a...

Orbiting Ganymede and Europa

by Paul Gilster | Feb 7, 2011 | Outer Solar System | 9 Comments

Back in December, NASA published its report on the Europa Jupiter System Mission (EJSM), noting how mission goals that were separately developed by NASA itself and the European Space Agency have now melded into a unified strategy. We're looking at orbiters around two of Jupiter's moons, a NASA vehicle around Europa and an ESA orbiter around the other Jovian 'water world,' Ganymede. The December report explained the derivation of each mission: The Europa Jupiter System Mission (EJSM) would be an international mission with an architecture of two independently launched and operated flight elements. Its theme and goals are derived from the US National Research Council's Planetary Science Decadal Survey [SSB 2003] and the ESA Cosmic Vision document [ESA 2005]. These reports emphasize as key questions for solar system exploration: 1) the origin and evolution of habitable worlds, and 2) processes operating within the solar system. Image: The NASA Jupiter Europa Orbiter would address the...

Sails, Abandoned Concepts, and the Long Haul

by Paul Gilster | Feb 4, 2011 | Sail Concepts | 28 Comments

Remember Arthur C. Clarke's "The Wind from the Sun"? The short story, telling of a race from the Earth to the Moon via solar sail, appeared in 1964, portraying the vessel Diana and its 50 million square foot sail, all linked to its command capsule by a hundred miles of cable. In those days, the sail idea was newly minted and more or less the domain of science fiction buffs, who had first encountered it in Carl Wiley's "Clipper Ships of Space," a non-fiction article written under a nom de plume for Astounding Science Fiction in 1951. The 1960s would see tales like Poul Anderson's "Sunjammer" and Cordwainer Smith's haunting "The Lady Who Sailed the Soul." Addendum: When I say the idea was 'newly minted' (above), I'm referring to the engineering ideas that could go into an actual mission. The idea of solar sailing itself goes back much further -- see my Centauri Dreams book for the whole backstory. Wiley's sail concept was startlingly ambitious for its time, an 80-kilometer design that...

Musings on Kepler’s Latest

by Paul Gilster | Feb 3, 2011 | Exoplanetary Science | 75 Comments

The data from Kepler’s first 136 days of operation could not be more interesting. As discussed in yesterday’s news conference, we now have fully 1235 exoplanet candidates from Kepler’s transit observations, and it’s worth quoting principal investigator William Borucki (NASA Ames) on the significance of the results thus far: "We went from zero to 68 Earth-sized planet candidates and zero to 54 candidates in the habitable zone - a region where liquid water could exist on a planet’s surface. Some candidates could even have moons with liquid water. Five of the planetary candidates are both near Earth-size and orbit in the habitable zone of their parent stars." Statistical analysis by the Kepler team shows that between 80 and 90 percent of these candidates are likely to be real planets. Remember that the spacecraft is staring at 156,453 stars in a patch covering 1/400th of the sky, located in the constellations Cygnus and Lyra. What it’s giving us is a statistical sample of stars in a...

The Remarkable Kepler-11

by Paul Gilster | Feb 2, 2011 | Exoplanetary Science | 19 Comments

Last June Centauri Dreams readers were excited about the release of Kepler results, but miffed that so much of the most interesting material was held back for later release. Now we have the release of these data, and the first thing I want to do is direct you to Greg Laughlin's systemic site, where you can find a follow-up characterization flow chart to help work through systems of interest. Laughlin calls it a 'template for the treasure map,' and it's available in full here. What happens next? Laughlin (UC-Santa Cruz) notes the process: "Once the candidates hit the stands, there will be a rush to skim the cream, and a mobilization of follow-up observational campaigns to capitalize on the best opportunities in the data set." He also reminds us that the brighter the parent star, the better the chances for delving deep into its exoplanetary mysteries. We're in cream skimming time indeed, and we'll have plenty to talk about in coming weeks. We'll carry on tomorrow with thoughts on the...

Kepler News Conference Today

by Paul Gilster | Feb 2, 2011 | Exoplanetary Science | 1 Comment

The NASA news conference announcing the latest Kepler results will take place today at 1800 UTC (1300 EST) at NASA headquarters in Washington. You can follow the action live on NASA TV. The participants are: Douglas Hudgins, Kepler program scientist, NASA Headquarters, Washington William Borucki, Kepler Science principal investigator, NASA Ames Jack Lissauer, Kepler co-investigator and planetary scientist, NASA Ames Debra Fischer, professor of Astronomy, Yale University I'll hold today's main post until after the embargo on the Kepler news lifts.

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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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