Where common sense and the film divide is just how best to dodge an oncoming meteor. I wrote a while back on the idea of painting one side of the asteroid black while beaming heat onto it, causing the asteroid to shift course. It’s a neat idea, but not nearly as neat as the gravity tractor, not just because this approach is more elegant, but because there’s a British company called EADS Astrium that announced last week that they could actually build one if it were needed.

The idea for the tug first proposed by NASA scientists Edward Lu and Stanley Love in a paper in Nature in 2005. The pair realized that sure, we could change an asteroid’s course by docking a rocket onto the asteroid and pushing it, but landing on an asteroid is really hard: The asteroid is an extremely fast-moving target, and often it rotates asymmetrically around its axis, meaning that a lumpy part of the asteroid could smash a relatively teeny rocket in its rotational path. But, the scientists argued, the spaceship could hover 200 meters or more above the asteroid and use their mutual gravitational attraction to form a “towline” between the two. Then ship could use its own propulsion to slowly pull the asteroid to another course. It would have to push very gently to avoid breaking the bond and flying away, but over the course of 15 to 20 years, the asteroid could be persuaded to miss our planet.

The idea of a gravity tractor has been refined (PDF) by scientist Bong Wie, working at Arizona State University, who proposed the use of solar sails to eliminate the problem of fuel capacity on the satellite. (Love and Lu’s proposal relied on nuclear energy generators for power in their design.) Solar sails capture the momentum from photons of solar radiation to provide propulsion. By properly angling the sail (Wie proposes 35 degrees), the body of the space ship can be moved in the desired direction. The sail can take months to build up significant velocity, but since it has a long time to accomplish its tugboat-like task, this isn’t inherently a showstopper. That said, solar sail technology is still in its infancy—it’s only been tested on a very small scale by American and Japanese scientists in space—so it’s not ready for large-scale deployment just yet.

EADS Astrium’s design uses four ion thrusters of the sort used on Deep Space 1.  Each is aligned to keep the device hovering above the asteroid while gently pulling the asteroid via it’s gravitation “towline” off course. The ship will be 30 meters (about 98 feet) across and weigh about 10 tons. In news articles, Astrium representatives say they haven’t even built a prototype yet, but they’re convinced they can bang one out if necessary.

All of which puts us back to the question of whether there’s enough capacity to provide the necessary early warning to build and launch a gravity tractor in time to have it work. Since NASA currently tracks about 6,000 asteroids, of the 100,000 out there, I’m going to go with no.

So, without further ado, here is what it would have looked like if a large object hit the Earth, during the 70’s, and many, many movie stars from that era (including Malden, Sean Connery, Natalie Wood, Brian Keith from Family Affair and a presidential Henry Fonda) had to run around reacting to it.

Question: How big an asteroid would be needed to completely destroy a planet?
That’s easy. It would have to be really, really big or moving very, very fast (or both for a real whopper of an impact), but there are some subtleties that are worth explaining.

First off, let’s admit that we’re really concerned with how big an asteroid would destroy planet Earth, especially life on Earth. I’m a bit more worried about my home planet than Mars, Jupiter, or even Pluto and even more worried about all the life we see around us (not to mention ourselves!). Earth is far more important from the human perspective, so let’s tackle that question.

Frighteningly, many large objects have hit Earth. Real whoppers. That’s a bit scary to think about. The good news is that the Earth is still here, so apparently large impacts of the planet-destruction kind rarely happen. We do know that smaller impacts have happened, such as the meteorite that hit the high Arizona desert just east of Flagstaff, at the site known as Meteor Crater. If we could count the impacts, we could gauge how frequently and when the impacts took place.

However, it is hard for us to find evidence of all the impact craters on Earth today. This is mainly due to erosion, which washes away the evidence by slowly filling in the craters, but looking at the Moon, where erosion is for all intents and purposes non-existent, we see that our nearest companion has been pummeled a lot, though mainly in the distant past. It, too, is still here and in one piece. The far side of the Moon, which always points away from the Earth, has a lot more craters than the side facing the Earth, which makes sense because the far side is more likely to be hit—it’s a bit harder for asteroids to sneak by the Earth and hit the shielded side of the Moon (though some have) than to hit the exposed side.

In fact, the Moon itself holds the key to what was probably the largest impact that the Earth has experienced (and hopefully will ever experience). Before I explain what we know about this biggest of all collisions, it is important to understand what we currently know about the formation of the solar system.

Stars form when dense and cold gas and dust that is prevalent in galaxies like the Milky Way slowly collapses under the influence of gravity. Astronomers see these forming stars just about everywhere we look—from regions practically next door, like the Orion Nebula, to the most distant galaxies we can see with the Hubble Space Telescope. As the star forms, a disk of leftover material takes shape through the combined effects of angular momentum and the force of gravity. These disks become fairly violent places as small particles of material slowly accumulate to form specks of dust, then pebbles, boulders, and ultimately planets. Astronomers have seen such disks in various stages of evolution with powerful telescopes.

Current models of planet formation gauge the time to go from a disk of gas and dust to a fully formed planetary system at about a million years, depending on the mass of gas and dust available and some other factors. Astronomers are not entirely sure how the process proceeds, but they have developed telescopes designed to peer through the material surrounding these forming stars to try and pin down the details. A prime example is the Spitzer Space Telescope, which observes in the infrared portion of the spectrum. Radio telescopes like the Very Large Array or the Atacama Large Millimeter Array (now under construction in Northern Chile) can also be used to effectively study the star- and planet-formation process, because the long-radio wavelengths they receive can escape the dense molecular clouds, unlike visible light.

It is now generally accepted that the Moon formed when a large, Mars-sized object crashed into the Earth very soon after the Earth itself formed. This collision dug deep into the Earth’s crust and threw off material from as deep as the Earth’s mantle into orbit where it was pulled together by its own gravity to form the Moon. This explains why rocks brought back from the Moon are composed of fairly lightweight minerals and rocks, containing little to no iron or nickel (metals found at the core of the Earth rather than the mantle). It also explains why the orbital plane of the Moon doesn’t line up with the orbital plane of the Earth itself (the impactor came from a different orbital plane). From dating the ages of rocks, geologists know the Earth is 4.65 billion years old, while the Moon is a bit younger, about 4.6 billion years old, evidently created in a subsequent massive collision.

So, in some sense, Earth wasn’t “destroyed” by an impact of an object the size of Mars that hit the Earth a somewhat glancing blow, but a more direct impact of an even more massive object could easily have had enough energy to seriously disrupt the Earth. Even so, in this case some kind of residual object would have formed, perhaps even two, and if life had taken hold after the planet and its companion cooled down, we might live in a true double planet system. Imagine looking up each night and seeing a blue companion planet in place of the Moon, with its own continents, weather, and oceans. That would be quite a sight.

What about life-ending impacts?
By studying the fossil record, geologists have identified sudden mass extinctions of species. They count the type and number of species in different layers of rock and can see when the number of species changes significantly. Two of the most significant extinction events are called the K-Pg boundary (a.k.a. the Cretaceous-Paleogene event) and the Permian-Triassic event.

The Permian-Triassic event took place about 251 million years ago. Although it is not entirely clear that major impacts caused this extinction, it is clear that the Earth’s life suffered an extreme setback. This extinction event led to the loss of 96% of marine species and 70% of terrestrial vertebrate species. Ponder this for a minute: This means that nearly all marine life was completely wiped out. More than two-thirds of all terrestrial animal species disappeared. Even many insect species—among the best survivors on the planet—were wiped out as well. This event is commonly referred to as the “Great Dying”—suffice to say it would not have been pleasant time to be alive. Although multiple impacts by large asteroids is a likely explanation for the Permian-Triassic event, there are other possibilities and research continues.

The K-Pg event took place 65.5 million years ago and is fairly clearly caused by the impact of a large asteroid. A thin layer of sediment with a high concentration of iridium was laid down around the world in a very short period of time. Iridium is very rare in the Earth’s crust, because it sank along with iron to the Earth’s core, but it’s often found in asteroids. There is also evidence of significant geologic activity around the time of this extinction event, which led to the loss of about 75% of all extant species, but most geologists believe it was caused by a giant impact near today’s Yucatan peninsula, forming the so-called Chicxulub crater. It is still not clear if the impact and its debris cloud (and tsunamis) were the sole cause of the extinctions or if secondary causes (chemical changes in the atmosphere or oceans) had a role to play. Again, research continues.

What can we take away from these extinction events? Life is both pretty tough and pretty disposable. Although life as a whole goes on, your species may not get a golden ticket. Impacts happen that can destroy most life on Earth. The good news is that life managed to survive and ultimately re-conquer the ocean and land, just not in the same forms that existed before. It is one of the amazing things about life on our planet that evolution guides both the long-term survival of life generally and the development (and extinction) of individual species. Life goes on, but any individual species may not.

Astronomers have begun multiple projects to scan the solar system and identify potential asteroids that might impact the Earth. Hopefully by identifying possible life-threatening objects, we could come together worldwide to somehow save ourselves (and all the other life on the planet). Right now, destroying or nudging an asteroid on a collision course would be a tremendous challenge, but it seems that impacts are few and far between, so we probably have enough time to develop the technology necessary for planetary protection.

The Internet may be crumbling, but think of the time that would free up! [via Futurismic]

“Junk DNA” science may cure HIV, probably won’t create race of superhuman mutants.   [via SciFi Scanner]

Migrant workers may soon be able to telecommute.  [via SciFiWire ]

SciNoFi is not alone.  Terminator TV fans mobilize to save their show. [via eonline.com]

And the first Star Wars may have been 30+ years ago, but its spirit lives on in the hearts of harp music loving pre-teens everywhere [via The Website at the End of the Universe] :

Image from Wikipedia

What exactly was Kara, and were people chasing down a rabbit hole when they assumed her father was Daniel, the missing 8th model cylon?

Ron Moore: Daniel is definitely a rabbit hole. It was an unintentional rabbit hole, to be honest. I was kind of surprised when I started picking up [that] speculation online.

For those of you who don’t know, there was a deep part of the cylon backstory that had to do with one of the cylons that was created by the final five [called Daniel. Daniel] was later sort of aborted by Cavill… it was always intended just to be sort of an interesting bit of backstory about Cavill and his jealously. A Cain and Abel sort of allegory. Then people really started grabbing on to it and seizing on it as some major part of the mythology. In couple of interviews and in the last podcast I tried to go out of my way to say “look, don’t spend too much time and energy on this particular theory,” because it was never intended to be that major a piece of the mythology.

David Eick: It’s like Boxey in that way!

Moore: Kara is what you want her to be. It’s easy to put the label on her of “angel” or “messenger of God” or something like that. Kara Thrace died and was resurrected and came back and took the people to their final end. That was her role, her destiny in the show… We debated back and forth in the writers’ room about giving it more clarity and saying definitively what she is. We decided that the more you try to put a name on it, the less interesting it became, and we just decided this was the most interesting way for her to go out, with her just disappearing and [leave people wondering exactly what she was].

We see Galactica jump away from the Colony. Are we to assume there are a lot of pissed off Cavills out there still, or were they destroyed?

Moore: The final [cut] came out a little less clear on that than I intended…. It was scripted and the idea was that when Racetrack hits the nukes—the nukes come in and smack into the colony—it takes the colony out of the stream that was swirling around the singularity and [the colony] fell in and was destroyed. I think as we went through the [editing process], when we kept cutting frames and doing this and that, one of the things that became less apparent was that the colony was doomed. The intention was that everyone who was aboard the colony would perish.

At what point did you decide to make it Earth-of-the-past that we were going to wind up on, and what was your reason for that?

Moore: We decided that a couple of years ago. I don’t think we ever really had a version of the show where we [were] in the future or in the present, those didn’t seem as interesting. In the early [development of the show], we would talk about the fact that we would see a lot of contemporary things in the show from language to wardrobe to all kinds of production design details. That only made sense to us in terms of a lot of things that we see in the show and we feel are taken from our contemporary world are actually theirs to begin with. [They] somehow spread down through eons and came to us through the collective unconsciousness. Or, more directly, [as when] Lee said we would give them the better part of ourselves.

Eick: There was a time when we were talking about “they land, and its Pterodactyls and Tyrannosaurus Rex.” But the idea that they were part of the genus of humankind seemed like the right—and more affordable!—way to do that.

Moore: We also had this image of Six walking through Times Square that we came up with long ago.

Who attacked the original Earth?

Moore: The backstory of the original Earth was supposed to be that the 13th tribe of cylons came to that world, started over and essentially destroyed themselves. There was some internecine warfare that occurred among the cylons themselves, which was another repetition in the cycle of “all of this has happened before and all will happen again.” Even they, who were the rebels that split off, [had] enough of humanity in them as cylons that they eventually destroyed themselves.

Why did Cavill decide to kill himself?

Moore: Cavill killing himself actually came from Dean Stockwell [the actor who played Cavill]. As scripted in that final climatic CIC battle, Tigh was going to grab Cavill and fling him over the edge of the upper level and he was going to fall to his death. Dean called me and said “y’know, I just really think that, in that moment, Cavill would realize the jig is up and it’s all hopeless, and he should just put a gun in his mouth and shoot himself.” And I said: “…Okay!”

For the actors, what was the last scene that you filmed and what was the mood like on the set?

Mary McDonnell: My last scene was Laura Roslin’s last moment in the Raptor. That was about 3:45 am on a very small set. I think I was one of the first people to wrap—she died and we all hugged, and my son and I went to the airport and went back to LA… It happened quickly, it was set to happen a week later and the schedule was changed, so suddenly it was over, it was really interesting, very much like the show for me.

Edward James Olmos: My last day was when I was on the mountainside and it was the last moment that I was on camera. It was quite an experience all the way around, that moment in time. I think everybody had a real easy time [acting] with the emotions that we had at the very end, it’s pretty honest all the way around. The last time that I saw Starbuck and Lee was the last scene where I saw them [in the show]. Pretty intense.

McDonnell: But we’re here, and we’re alive! I wore bright blue so you would know I was alive.

With the use of “All Along The Watchtower,” are you trying to get at some notion that there is some universal consciousness that goes back as far as the human/cylon races’ arrival?

Moore: The notion is sort of how you posited it. The music, the lyrics, the composition, is divine, eternal, it’s something that lives in the collective unconsciousness of everyone in the show and all of us today. It’s a musical theme that repeats itself and crops up in unexpected places. Different people hear it and pluck it out of the ether and write songs. It’s a connection of the divine and the mortal. Music is something that people literally catch out of the air and can’t really define exactly how they composed it. [So] here is a song that transcends many eons and many different people and cultures and the stars, and was ultimately reinvented by one Mr. Bob Dylan here on Earth.

Eick: It was a simple way, I thought, to communicate clearly the idea [the show is not set in the future.] That this is a story about a culture that gave birth to ours. There was an episode in season one in which Helo and Sharon are running for their lives. They hole up in a diner and there’s a cylon centurion cornering them. For the longest time we planned to have an old jukebox in the diner that would play “Yesterday”, or whatever we could afford—

Moore: Not “Yesterday.”

Eick: —Probably not “Yesterday.” Something from The Guess Who perhaps. I think we felt it was too soon. It would confuse things and…people would just be thrown by it, but we were thinking about it that far back, that music would be a great way to say to the audience that it follows [a] cyclical theme of “this has all happened before and will happen again.” This culture is the one that gave birth to ours, so that all the colloquialisms and all the slang that you hear and the behavior that is idiosyncratic—playing cards or whatever—we get that from them, not the other way around.

There’s been a lot of talk about how setting an end date for a scripted serial helps to recharge it. Did you find that true?

Moore: In terms of the writers’ room it certainly focused us. We made the decision that fourth season was going to be the last season once we got to the end of the third season. We had writers’ retreats, and we had dedicated sessions to say “this is the end, what’s the last story, what’s the final arc?” It really made everybody very focused and very specific about exactly how this was going to line up. Part of the motivation to make it the final season was that we didn’t want to get to the place where we felt like the ship was keeling over and we were having a problem. We all instinctively felt that the show had the reached the third act by the time the show got to the end of that third season.

Eick: Going back a year before that, Ron and I sat down for our biannual “what the hell do we do this year meeting?” Heading into season three there was a real sense of creative frustration. We wanted to expand the show and … find a new ways [of] story telling. [So season three] became what we call the cylon-centric season. It’s when we introduced the base ship, it’s when we introduced some new cylons. It gave the show life, but after a year of that, when we sat down heading into season four, it was a much shorter conversation. It was basically “okay, what if we end it? What if we just decide it’s over?” Let’s call this…the dovetailing season. If we know that going in, how would that inform story telling decisions?” So it was a very early decision. I remember from my perspective going into that 4th season there was a different energy on the set. There was tremendous focus and concentration that I was getting from the entire ensemble.

McDonnell: Part of what was extraordinary about that is as you are able to view [the end approaching] you can then kick into gear and plot your finish. What that ends up doing is simplifying things for you. You know where your head is and you can let go in many moments were you probably would have worked very hard [before, but] you didn’t need to. So a lot of us felt a kind of simplification. A kind of humility that came over us and that gives you a lot of energy. You just know where you are going and you are proud to be a part of it. And you let go. That was the experience I think many of us had.

Olmos: We had a meeting at the very beginning of the show and we all, 13 of us, sat down in my trailer—

McDonnell: He had the biggest trailer.

Omos: —it was beautiful! And we sat down as we discussed the possibilities. I talked to them about making sure we understood that if, by chance, this situation was to move forward and we were to do this as a series, and this was to go on to for one year, four years, ten years, who knows, that we had to understand what that meant… I just knew that…the story would have a beginning, a middle and an end, and that we had to pace ourselves.

So at the end of the third season, beginning of fourth season, we had a meeting, and we were told then that this was going to be the final season. Everybody got very depressed…I don’t think any of the actors wanted to stop the show… But we had hit the end, we were going into the fourth and final act. And we knew it. So we talked about the very first time we ever got together, and we said it’s like a marathon. In marathon you have to start off fast, really really intensely strong, your first mile has to extraordinary. Then the next 24 miles have to be consistent…. And then the last mile has to be the strongest mile that you’ve run the whole 26 miles…To win it, your final mile has to be your strongest mile… So we knew where we where coming from, we knew where we were, and now we knew where were going… I think that led to some of our strongest performances.

In the last scene, are “Six” and “Baltar” angels or demons?

Moore: I think they’re both. We never try to name exactly what the “Head” characters are—we called them “Head Baltar” and “Head Six” all throughout the show, internally. We never really looked at them as angels or demons because they seemed to periodically say evil things and good things, they tended to save people and they tended to damn people. There was this sense that they worked in service of something else. You could say “a higher power” or you could say “another power,” [but] they were in service to something else that was guiding and helping, sometimes obstructing, and sometimes tempting the people on the show. The idea at the very end was that whatever they are in service to continues and is eternal and is always around. And they too are still around…and with all of us who are the children of Hera. They continue to walk among us and watch, and at some point they may or may not intercede at a key moment.

We’ll leave the debates over the acting, direction, and overall adaptation to others (except to say that Jackie Earle Haley stole the show). But one aspect worthy of analysis is the story’s main conflict—the constant “looming” nuclear holocaust. Granted, we never actually see any evidence that the aforementioned holocaust is looming, save a few shots of Nixon upping Defcon levels—but we’ll address that later. When Alan Moore first published the book in 1986, the apocalypse on everyone’s mind was Cold War atomic bombs—which, as we’ve noted, no longer pack quite the same anxiety punch as, say, biological weapons. Today, gas masks and duct tape have replaced air raids and backyard shelters in the popular conscious, to the point where seeing mushroom clouds onscreen feels like you’re watching an ’80s homage.

Of course, none of this means that the nuclear threat is any smaller now than it was three decades ago: The danger of nuclear war is still present, and fear of missile attack still drives plenty of policy and military tech decisions worldwide. But, like Bird Flu, nukes seem to have a PR problem: Despite the fact that they could wipe us all out, the thought of them isn’t all that scary.

Which is really the main problem for Snyder and his estimated $125 million budget: No matter how faithful your script and powerful your characters, it’s tough to keep a story suspenseful when you’re working towards a climax that doesn’t pack a serious punch. Not helping is the fact that the film completely ignores the other side—the Russians. We get a few choice shots of Tricky Dick mumbling about war, but never once do we see Gorbachev ordering missile launches or troop mobilization.

Granted, world annihilation isn’t dull—it’s still enough to keep an audience engaged for 2 hours and 43 minutes. Plus Snyder never misses a chance to smack us with stakes-raising reminders of devastation (we counted at least 8 shots with the Twin Towers in the background). And when the destruction does come to the Big Apple (why do TV shows and movies always love to decimate New York?) Snyder saves us the book’s graphic images of strewn corpses and bombed-out buildings, instead focusing on the internal struggle among the Watchmen ranks. Nine million people sacrificed for the greater good, meh—but we’ll watch one lovable sociopath in a ski mask.

So should Snyder have updated his apocalypse with biotech? He’d have faced the wrath of fans had he done so. Plus who would think nuclear war could ever get boring? It’s enough to make you wonder what the next big all-consuming fear will be. Oh, wait, we know that already: thinking robots.

Image courtesy of Warner Bros.

But hopefully we’ll have some more time than that, maybe on the order of 40 or 50 years. Then we can make plans. In How I saved the World, Valentin Ivanov’s short story from Diamonds in the Sky, a heroic team of astronauts are living on the surface of an asteroid called “The Hammer” and…painting it black. 

OK, here’s the theory: A rotating object in space will absorb heat and light from the sun on one side, and emit the photons (cool off) on the other side. As the photons are spat out, the object will be pushed, at least a bit, in the opposite direction.  To deal with the 200 million-ton rock-of-death in the story, the entire world has mobilized its resources. The Chinese are building giant solar batteries which will power giant lasers built by the french. The lasers will be pointed at the sunward side of the asteroid, which itself will have been painted black by Russian and American astronauts. The black paint increases the amount of energy the asteroid will absorb and emit, and thus propel the asteroid toward the sun faster, and, in this case, causing it to miss the Earth. Phew!

Of course, there are potential problems with this theory. Asteroids have low gravity, and they are mostly gravel and loose rock. It’s not clear if the paint would remain in place. And the expense of trucking all that paint into space would not be inconsiderable. So what are the alternatives? One idea involved installing a lot of small, solar power rockets which would slowly, over time, change the direction of the asteroid. Another would be to install a conveyor belt that digs out asteroid  dirt and flings it out into space, changing its direction by Newton’s Third Law.

But before any of these can be useful, there needs to be long-range asteroid detection, so the planet isn’t caught off-guard. NASA currently relies on optical telescopes and radar echoes beamed from Aricebo radio telescope in Puerto Rice. In 2005, they were able to detect the Apophis Asteroid, which appeared headed for a maybe-hit with the Earth until additional data allowed analysts to refine their estimate and reduce the probability of an impact in 2029 or 2036.  So I think we can count getting a 25-year advance warning a success, but last October, astronomers were surprised when a bus-sized asteroid burned up in the atmosphere over  Africa. The event lead to a call for more funding for asteroid detection, but with the world economy doing its own freefall, it’s not clear that we’ll see any moves on that for some years yet.

Image courtesy of NASA

The core point of Planet Killer is that there natural things out in space that are a lot more dangerous than any invading fleet of aliens you could care to mention. (The Bad Astronomer, Phil Plait, has written an excellent book on this whole notion with the subtly-titled Death From The Skies: These Are The Ways The World Will End, which Kevin mentions in his commentary at the end of the story.)

The kind of cosmic event that can make for incredibly beautiful Hubble Space Telescope pictures, can also spell death for anyone who happens to be close by. Unfortunately for us, in the case of a Gamma-ray burst of the sort that is at the heart of the mystery of Planet Killer (I told you to read the story first!), being close by can mean “in the same galaxy.” Gamma-ray bursts are believed to be produced by stars getting swallowed up be a black hole or the merger of two super-dense neutron stars. In either case, the result is two beams of intense radiation shooting away from the triggering event like beams from a lighthouse. Each beam is big enough and powerful enough to fry any solar systems that happen to have the misfortune of sitting in its path, even if the Gamma-ray burst originates on the other side of the galaxy.

Much is unknown about these bursts and how they are produced. But although unpredictable, Gamma-ray bursters are bright enough to be seen at intergalactic distances, and there are enough galaxies visible in the sky to make keeping an eye out for them worthwhile. In the past, the difficulty has been coordinating observations, so that the detection of gamma rays can be correlated with other types of radiation, such as light, allowing us to pin down the precise origin of such bursts. Fortunately, orbiting satellites like the recently launched Fermi Gamma-ray Space Telescope have made this task much easier. Just last month, the Fermi detected the most powerful Gamma-ray burst ever—fortunately one which occurred a comforting 12.1 billion light years away.

With buzz already building for The Road, a post-apocalyptic movie starring Viggo Mortensen set to come out sometime in 2009, Science Not Fiction decided to take at look at some of our favorite after-the-end-of-the-world scenarios. I excluded the various incarnations of War of Worlds because the book is basically an extended flashback from the safety of a rebuilt future, and the movies are apocalyptic rather than post-apocalyptic. Similarly Independence Day and Deep Impact are about averting armageddon. Twelve Monkeys and Oryx and Crake have post-apocalyptic scenes, but the back bone of their narrative is firmly in the pre-apocalyptic world–the selections below are all about life in the no-holds-barred aftermath. So in chronological order:

1. A Canticle for Leibowitz (1950) Echoes of Walter Miller Jr.’s novel have popped up in science fiction for decades, notably in Babylon 5 and Anathem. Canticle features a monastic sect devoted to preserving technology in the centuries following the fall of civilization.
2. Lord of The Flies (1954). Set in the aftermath of a nuclear war* a group of boys are stranded on a tropical island. An allegory for the collapse of civilization as a whole, things soon turn ugly and shades of Lord of the Flies are found in many later post-apocalyptic works.
3. Mad Max (1979) Although the argument could be made that the sequels were better than the somewhat disjointed original (in particular Mad Max Beyond Thunderdome), Mad Max’s iconic look and feel has been copied by countless other movies, in many ways defining the visual vocabulary of the post-apocalyptic.
4. The Day of The Triffids (BBC TV adaptation, 1981) Based on John Wyndham’s 1951 novel of the same name, The Day of The Triffids featured a double whammy–a nation struck by blindness and the escape of the deadly Triffid plants. The scenes of a deserted London inspired 28 Days Later, and the clacking noise made by approaching Triffids in the BBC adaptation became one of the scariest sounds ever.
5. Threads (1984) Continuing the BBC’s 1980’s love affair with the end of the world, Threads is an uncompromising and utterly bleak tale of life in a British city (Sheffield) before and after nuclear armageddon. Incorporating documentary style elements, the script pulled no punches and was noted for its technical accuracy, including the effects of a nuclear winter.
6. The Quiet Earth (1985) I mentioned this film before in Science Not Fiction’s list of the 10 Most Underrated Science Fiction and Fantasy Movies, but it deserves to appear again — a scientist awakes to find a world in which (almost) every human being has been mysteriously killed instantly.
7. The Postman (Original 1985 novel, not the Kevin Costner film adaptation) The movie version was weak, but the novel remains one of my favorite books. Without sugarcoating life in a destroyed United States, the book nonetheless is unusual among post-apocalyptic fiction for its moving and believable optimism.
8. Cherry 2000 (1986) Yes, it’s a classic B-movie. But this hero-quest romp had some standout touches, including the idea of a world that can’t afford anything new and the memorable and mentally unbalanced Lester (a sort of psychopathic self-help guru.)
9. 28 Days Later (2002) Confirming the fall of nuclear war and the rise of biological disaster as the standard route to a post-apocalypse, 28 Days Later also breathed new life into the zombie genre. A gripping and intelligent plot packed a huge emotional wallop.
10. I am Legend (2007 movie adaptation). Based on the 1954 novel, the amazing visual storytelling and convincing performance of Will Smith in an empty New York City knocked this tale of humanity’s twilight out of the park.

ETA *(Or not, there’s an alternative explanation for the precipitating events that force the boys’ original evacuation, see the comments below. But it still stands as a microcosm of life after global civilizational collapse)

Traditionally, Jupiter has been seen as protector of the Earth. The idea is that comets from the outer solar system which might otherwise smash into the Earth (a la Armageddon and Deep Impact) get sucked into Jupiter’s gravity well instead and are swallowed up, similar to how comet Shoemaker-Levy collided with Jupiter in 1994. Now, Kevin and his colleagues have created a detailed simulation of the solar system that suggests that Jupiter might be responsible for kicking comets towards the inner solar system, where the Earth lives.

This research also has implications for the search for extraterrestrial life, and especially intelligent life — up until now, scientists have worried that if a solar system didn’t have something like a Jupiter, it might be too dangerous for life to get very far before getting wiped out by an impact. If Jupiter actually makes things worse for inner planets, we might be more likely to find life in solar systems without big gas giants.

Work continues apace on invisibility. [Futurismic]

Stretchy electronic fabric presages wearable computers and robotic clothes. [Pink Tentacle]

New hemispheric camera could lead to artificial eyes. [SciFi Scanner]

Liquid metal defies gravity. [io9]

I for one welcome our new robot overlords.

In the real world, we’re actually making progress on what could be the distant ancestor of this technology. At places like Brown University, MIT, and Berkeley researchers are working on synthetic biology: the goal is to reprogram the DNA of microbes so that they can be used to construct minature machines, or act as tiny computers to process information. (A special shout out to DISCOVER’s 2006 Scientist of the Year, Jay Keasling.) There is even a contest — The International Genetically Engineered Machine competition — hosted by MIT. Teams of students use a library of standard “parts” (genetic sequences that perform specific fuctions) known as BioBricks to make their creations. Winners of this year’s competition will be announced in November.