"Ridiculously difficult" -- describes the challenge of landing a probe on the surface of the comet, as summarized in this simulation: How to Land on a Comet.
On November 12, the European Space Agency's Rosetta Spacecraft will drop the Philae Lander onto Comet 67P/Churyumov-Gerasimenko -- in the first ever soft landing of a craft on a comet. The landing site, named Agilkia, is located on the head of the comet. Philae will drill into the surface to analyze the comet's composition -- see this timeline of science experiments to be undertaken by the lander. Meanwhile, Rosetta will continue to monitor changes on the comet through 2015.
The event will be covered live on NASA and the Science Channel. Am I excited? *
== Space News ==
No roundup about space would be complete without first mentioning the tragic and disastrous crash of the Virgin Galactic Spaceship Two... whose problem we hope will soon be solved and resolved, so that Richard Branson and Burt Rutan will achieve their aim -- offering the uber-rich thrills that in-turn subsidize the development of space. (As portrayed in a recent novel.)
... and the explosion of the Orbital Sciences Antares rocket. Such coincidences in timing aren't uncommon. Hey, space is hard! Still, the sci fi nut inside asks: are we under attack by UFOs? (Yeah, silvery guys... I'm lookin' at you.)
Seriously, our sympathy to both teams, with best wishes for recovery and future success.
On November 12, the European Space Agency's Rosetta Spacecraft will drop the Philae Lander onto Comet 67P/Churyumov-Gerasimenko -- in the first ever soft landing of a craft on a comet. The landing site, named Agilkia, is located on the head of the comet. Philae will drill into the surface to analyze the comet's composition -- see this timeline of science experiments to be undertaken by the lander. Meanwhile, Rosetta will continue to monitor changes on the comet through 2015.
The event will be covered live on NASA and the Science Channel. Am I excited? *
== Space News ==
No roundup about space would be complete without first mentioning the tragic and disastrous crash of the Virgin Galactic Spaceship Two... whose problem we hope will soon be solved and resolved, so that Richard Branson and Burt Rutan will achieve their aim -- offering the uber-rich thrills that in-turn subsidize the development of space. (As portrayed in a recent novel.)
... and the explosion of the Orbital Sciences Antares rocket. Such coincidences in timing aren't uncommon. Hey, space is hard! Still, the sci fi nut inside asks: are we under attack by UFOs? (Yeah, silvery guys... I'm lookin' at you.)
Seriously, our sympathy to both teams, with best wishes for recovery and future success.
And we move on to ...
Is suspended animation possible? Can we 3D print whole structures on the moon? How about swimming the ocean of Europa?
Our leader at NASA NIAC - Jay Falker - explains the mission, to explore highly speculative ideas with small, seed grants. Watch this short video about NASA’s Innovative and Advanced Concepts group. I am proud to be on the council of external advisers.
YOU should be proud to be a member of a civilization that does stuff like this.
Indeed, cheer up by reading a fascinating article about the British Skylon Program, which promises air-breathing engine technology that could make genuine space planes possible. We appear to be entering the "barnstorming era" of space at last, when private risk-taking becomes possible and opens up many worlds of possibility. As the earlier (cheaper and easier) barnstorming era opened flight in the 1920s.
== More space! ==
Is suspended animation possible? Can we 3D print whole structures on the moon? How about swimming the ocean of Europa?
Our leader at NASA NIAC - Jay Falker - explains the mission, to explore highly speculative ideas with small, seed grants. Watch this short video about NASA’s Innovative and Advanced Concepts group. I am proud to be on the council of external advisers.
YOU should be proud to be a member of a civilization that does stuff like this.
Indeed, cheer up by reading a fascinating article about the British Skylon Program, which promises air-breathing engine technology that could make genuine space planes possible. We appear to be entering the "barnstorming era" of space at last, when private risk-taking becomes possible and opens up many worlds of possibility. As the earlier (cheaper and easier) barnstorming era opened flight in the 1920s.
Art often interfaces with science, but not quite like this. As reported by Adam Rogers (my former ArchiTECHS co-star) in WIRED -- The Warped Astrophysics of Interstellar -- it seems that the special effects team for Christopher Nolan’s upcoming (and much-awaited) film Interstellar consulted with another friend of mine — Caltech’s brilliant Kip Thorne, who supplied equations that Nolan’s team crunched and crunched… in order to show us what (according to Thorne) a Black Hole “will actually look like.”
This isn’t the first time that art rendered a best-image for science!*
But this is just plain terrific. If you are like me, you are bouncing against walls with eagerness to see Interstellar! Both as fans... and for what just the right piece of art may do to shatter the stunning cowardice toward new ideas that dominates today’s studio-Hollywood.
== More Comet News ==
Last month Comet Siding Spring grazed right past Mars, endangering our many satellite probes there... clever maneuvers enabled all of them to survive. More exciting, the comet, which passed within about 87,000 miles of Mars on October 19. NASA's Mars Atmosphere and Volatile Evolution (MAVEN) mission, NASA's Mars Reconnaissance Orbiter (MRO), and the ESA's Mars Express spacecraft all detected a change in the level of ions in Mars's ionosphere. The comet close approach apparently set up epic meteor showers -- bombarding Mars with thousands of fireballs an hour!
Last month Comet Siding Spring grazed right past Mars, endangering our many satellite probes there... clever maneuvers enabled all of them to survive. More exciting, the comet, which passed within about 87,000 miles of Mars on October 19. NASA's Mars Atmosphere and Volatile Evolution (MAVEN) mission, NASA's Mars Reconnaissance Orbiter (MRO), and the ESA's Mars Express spacecraft all detected a change in the level of ions in Mars's ionosphere. The comet close approach apparently set up epic meteor showers -- bombarding Mars with thousands of fireballs an hour!
Eau de comet? The Rosetta Probe sniffs Comet 67P/Churyumov-Gerasimenko -- and detects odors resembling "rotten eggs and horse pee" -- also known as hydrogen sulfide, ammonia and formaldehyde.
And comets beyond comets! Thousands of them observed flickering in and out near the new solar system of Beta Pictoris.
Bizarre Pyramid on Comet 67P? "It looks almost as if loose dust covering the surface of the comet has settled in the boulder's cracks. But, of course, it is much too early to be sure," comments researcher Holger Sierks."Yes, well, comet dust layers were predicted 30 years ago, in fact. *
==Space Updates==
NASA awarded contracts to Boeing and Elon Musk's SpaceX to ferry astronauts to and from the International Space Station, ending U.S. dependence on the Russian Soyuz for transportation of humans. It's about time! It also makes clear the advantages of competition, which Elon's company has restored.
The Sentinel program - developing satellites that can warn in advance of medium/small asteroids on collision course - reveals in vivid detail what the U.S. Defense Department had heretofore (for unfathomable reasons) deemed secret — that from 2000 to 2013 there were twenty-six “nuke-level” incidents, when meteors of asteroidal scale exploded in the atmosphere, delivering from one to six-hundred kilotons of energy.
A “city killer” strikes Earth once per century, though the greatest danger is if one of these events ever took place in a touchy region, possibly sending itchy trigger fingers racing for buttons.
A “city killer” strikes Earth once per century, though the greatest danger is if one of these events ever took place in a touchy region, possibly sending itchy trigger fingers racing for buttons.
Want another worry? Earth's magnetic north pole has been speeding up in its movement and this year passed its closest to true north. Interesting... and sci fi worrisome.
How cool is this? “Astronomers using the Hubble Space Telescope have located at least one and possibly three Kuiper Belt objects that NASA’s New Horizons spacecraft can reach after its flyby Pluto next year.”
Meanwhile, I am helping my friend Jon Lomberg (creator of Hawaii's famous "Galaxy Garden" and co-creator of Carl Sagan's Voyager Record) in his effort to get a similar trove of human wisdom and art stored aboard the New Horizons probe after it finishes doing science, screaming past Pluto next year.
Sign the petition for the New Horizons Message Initiative -- to send a crowd-sourced message to the spacecraft's memory.
Sign the petition for the New Horizons Message Initiative -- to send a crowd-sourced message to the spacecraft's memory.
== And yet more inspiring science! ==
Scientific American asks: “Conspiracy theorists may wonder, why does NASA’s next major telescope director need top secret clearance?” Interesting indeed. “The Webb telescope is being planned as a successor to the Hubble Space Telescope, and will peer at some of the farthest reaches of space and time. The $8.8-billion observatory is due to launch in 2018.” Past Space Telescope directors did not need clearance. But in fact, I believe that this event has little to do with the Webb Telescope.
Remember that NASA just took delivery of two Hubble class Keyhole space telescopes, no longer needed by the National Reconnaissance Office or NRO. I guess they want to be sure that, in converting those scopes for scientific work, sensitive tech does not leak . On the other hand, what if the Webb is being used as a civilian cover operation for next generation spook craft, just as the Hubble had been? Maybe an even bigger reason.
Remember that NASA just took delivery of two Hubble class Keyhole space telescopes, no longer needed by the National Reconnaissance Office or NRO. I guess they want to be sure that, in converting those scopes for scientific work, sensitive tech does not leak . On the other hand, what if the Webb is being used as a civilian cover operation for next generation spook craft, just as the Hubble had been? Maybe an even bigger reason.
Gamma Ray Bursters as cullers of life? These bursters may wipe out those systems that orbit near Galactic Center. “Only at the outskirts of the Milky Way, at more than 10 kpc from the center, this probability drops below 50%.
When considering the Universe as a whole, the safest environments for life (similar to the one on Earth) are the lowest density regions in the outskirts of large galaxies and life can exist in only ~ 10% of galaxies." Interesting hypothesis. On the role of GRBs on life extinction in the Universe, by Tsvi Piran, Raul Jimenez.
When considering the Universe as a whole, the safest environments for life (similar to the one on Earth) are the lowest density regions in the outskirts of large galaxies and life can exist in only ~ 10% of galaxies." Interesting hypothesis. On the role of GRBs on life extinction in the Universe, by Tsvi Piran, Raul Jimenez.
Tiny diamond nano threads could someday support a space elevator? See my earlier ruminations about how a space elevator beanstalk on the far side of the moon might (across 100 million years) save our planet!
Ten horrifying technologies that should never exist, by George Dvorsky, citing weaponized nanotechnology, brain hacking devices, weaponized pathogens...and more terrors.
Will “torpor” let us put astronauts into suspension (as in 2001: A Space Odyssey), saving resources for deep space missions? As I mentioned earlier, this work is funded by us at NIAC... actually, one of the less plausible grants, in the next decade or two. But good press!
Heh cute visualization to put things in perspective; How close is our closest neighbor, our moon "It’s tempting to think it’s much closer to Earth than it really is. The Moon has an average distance from Earth of 384,399 kilometers (or 238,854 miles if you prefer)....It turns out it’s far enough to fit every other planet in the solar system with room to spare, " notes astronomer Christian Ready.
Here's one rule of thumb. The distance from Earth to moon is ten times Earth's circumference. So wind a measuring tape ten times round the equator. That should do it. In fact... now that I put it that way, I am starting to suspect....
But never mind. Onward and let's foster a bold, ambitious, responsible but brave civilization!
====But never mind. Onward and let's foster a bold, ambitious, responsible but brave civilization!
*PS... am I excited about all this comet news? Excuse the pump heck-yeah. But way back then, for a while, I was a top comet-ologists. My doctoral dissertation created the present model of dust layers on an icy-rocky core. See it portrayed in Heart of the Comet. So heck yeah indeed! I am plenty jazzed.
24 comments:
SS2 - Whatever happens with VG, at least there are other viable companies working to offer the same or similar service. I'm not sure that SS2 is quickly fixable, nor that the 12 month delay is going to be acceptable to the financiers. This may be VG's death knell. It is also a warning to communities that pay for facilities (Spaceport USA, NM) out of tax monies, now stuck with the bill and a potential white elephant.
SS2's design might be fixable if the problem was an armed feathering that accidently triggered for some reason TBD. However with a few customers canceling their tickets and lookin for refunds, it may be indicative that a vehicle that flies to pieces so easily may not be very safe, certainly not for the elites.
Interstellar - mixed reviews so far. I've heard that an Imax viewing is worth it for teh space scenes, but that the movie falls apart concerning the plot. (And the science is very poor, apparently).
Skylon - it isn't quite like 1920's barnstorming and it does involve a lot of government support. However, IMO, it is shamefull how little support the UK has given to this project, and the blocks it has put in front of its development. It took a lot of effort for Bond to even get the UK funding, a sum that is paltry even by UK standards and a mere rounding error for the US DoD or even Nasa. It is also indicative of Britain's loss of scientific expertise that it required the EU to verify the inventive Sabre engine design. Like SpaceX, REL needs a high volume market to ensure that reusability reduces prices, a situation that will be opposed by incumbents. I truly hope that is realized and that REL becomes a leader in this market. Skylon makes SpaceX's approach look very old school. It wouldn't be out of place in a Gerry Anderson's "Thunderbirds" episoode.
And yes I am keeping my fingers crossed that ESA's Rosetta will pull of a successful landing. But even a failure will still allow Rosetta to capture a lot of very good data on the comet as it warms on its journey towards the sun.
Good comments Alex. The 1920s barnstorming era also had lots of govt support. Mail contracts and built airports. As the automobile also benefited, and rails before that.
On George Dvorsky's article.
1. A moratorium on weaponized nanotech wouldn't stop rogue groups or individuals from creating grey goo, and it would prevent any means of stopping it. I would prefer that every country produce large quantities of benign "blue goo" and spread it across the entire planet so it could overwhelm any malignant nano by sheer mass.
2. Cruel? Any young child is retarded by comparison to the average adult. Is it cruel to create children?
3. Create artificial intelligence first, then we'll talk about superintelligence.
4. If Time Travel were possible and you could change the past, history would be like it is in Hitchhiker's Guide to the Galaxy.
5. Imagine what would happen if every reporter at a political debate had a mind-reading device.
6. Pretty much the only reason someone would implant themselves with devices that could control them is if their government or employer required it or they wanted to be someone's puppet. Though, I can see someone wanting to back up their memories in the Cloud, which could be hacked, and they could become dependent on their externally stored memories.
7 and 8. Inevitable.
9. There's not really any point to driving a criminal insane from 1,000 years of imprisonment. However the technology would be a godsend for psychotherapists.
10. What is this even?
"The 1920s barnstorming era also had lots of govt support. Mail contracts and built airports. As the automobile also benefited, and rails before that."
Yes indeed. The difference is that the vehicles were privately built - trains/cars/planes and the government helped with infrastructure and markets - rails/roads/airports and, as you say mail. The same is true of airlines today - the airlines own their planes (or lease them) but governments build, and often run, airports, ATC, and the connecting infrastructure to airports. Today governments also pay for the spacecraft too - even SpaceX relies on Nasa funding to build its launchers by paying for a "market" of ISS cargo delivery and soon astronauts. Hopefully at some point the space market will become truly commercial. I suspect it will start with tourism and related activities, later extra-terrestrial resources and manufacturing to support commercial space activities.
Re Gamma ray bursts
I still don't see those as mass extinction events.
As they are on too short a time scale.
Even if an event managed to eliminate the ozone layer it could only do so on one hemisphere,
You could get major problems on one hemisphere but the other would be intact - which would not be a mass extinction event
Serious - yes - but not the sort of level that those guys were talking about
What sort of power level would it take to be a Mass extinction event?
A 1m2 column of air masses about 5,000Kg
So 1000Kj/m2 will input 200joules/kg to the air
That would increase the air temperature by 1 degree???
Apart from the effect on the ozone that does not seem too bad
Given that only one hemisphere can be effected you would need at least 100 times as much energy to effect one hemisphere enough to cause disastrous effects on the other one
That puts the danger from these events right down
Some early signs point toward the destruction of SS2 being a matter of pilot error - the pilot may have deployed the deceleration systems too soon. If so, the fix for that is software, prohibiting the system from deploying if the speed indicator is above a given level.
As for the proscribed technologies:
It would be cruel to create an intelligence that can suffer? Then we'd all better stop breeding right away - because everybody can suffer. Or, to quote a great philosopher, "Life is pain, Highness. Anyone who tells you differently is selling something."
And time travel doesn't worry me that much because I think Niven's First Law of Time-Travel holds - in any universe in which time travel is possible, and it's possible to change the past, time travel will never be invented. Because at some point, someone's going to figure that things are so screwed up that the only solution is to kill the inventor of time travel before he can succeed.
Alex Tolley,
Re: Skylon and govt assistance.
Bond's mistake, IMO, is in focusing on Skylon. The only part he had was the heat exchange system, which is ideal for assisting jet engines (particularly high-speed supersonic jet engines, but it should improve the efficiency of regular old sub-sonic turbo-fan engines.)
And yet Bond treated that large existing market as an afterthought. Something to tack on at the bottom of his presentation of a radical new SSTO space-plane for which the only part he's developed in 20 years is a particularly clever radiator.
Starting out solely as a maker of a part that improves the efficiency of jet engines is much more likely to attract commercial investment, and a maker of a part that dramatically improves military supersonic jets is more likely to get UK govt funding (or even US/DARPA). Once he has a profitable company, he can self-fund the Sabre engine, getting funding for a first-stage for an air-launcher. And once he demonstrates that, once he has a customer base, then and only then would he start talking about a SSTO Skylon.
Instead, he effectively spent 20 years standing on a hill, wearing a chicken suit, screeching "I am an eagle!" and wondering why people didn't take him seriously.
Re: SpaceX and govt support.
The impression I got was that SpaceX was pretty self-supporting during its early development. Falcon 1 had plenty of paying customers lined up in spite of losing the first three launchers. Falcon 5 (the original next step) would have similarly been fully booked.
The government funding allowed Musk to skip straight to Falcon 9 (which in my opinion probably did more harm than good, representing too big a step.) But his development path was potentially self-funding, provided he wasn't shut out of the commercial market by some dickishness by existing players.
[He still benefited from prior NASA research and USAF launch sites. But dealing with govt bureaucracy is apparently a major cause of cost and delay. So swings'n'roundabouts. Mo' money, mo' problems.]
[Turing: "difficult"]
David Brin,
Did the automobile get govt support prior to WWI military contracts?
Duncan Cairncross
"Re Gamma ray bursts
I still don't see those as mass extinction events. As they are on too short a time scale. Even if an event managed to eliminate the ozone layer it could only do so on one hemisphere,"
Apparently they produce nitrous oxide, which acidifies the air, the rain, then the seas. If the GRB is close enough, it will produce enough to kill everything that isn't already acid tolerant, or isn't deeply hidden. So in theory you can reset a planet all the way back to extremophiles.
[Coincidentally, nitrous oxide is also a plot point in Interstellar.]
Jonathan S,
Re: VG SS2
There's pilot error and there's "pilot error".
SS2 is known to be a violent ride, that can make it hard to read instruments. It accelerates fast, which means the pilot has to anticipate the gap between Mach 1.0 and 1.4 (when he's isn't, then is, supposed to unlock the tail boom.) And it seems like the tail boom was forcibly deployed by the airpressure (the pilot didn't hit the actual deployment trigger, only the unlock), which is an inherent design flaw and something that may not have been properly explained to the pilots ("Better to release late than early. Always err on the side of unlocking late.")
Hence the "pilot error" could turn out to be something that was inevitable by design, and just luck that they hadn't done enough powered flight testing for it to have already happened.
Re: Time travel.
Most of the "realistic" methods of time travel (creating "closed time-like curves") limit you to no further back than the invention of the time travel device. So if it's possible, it's still not going to affect us.
I'm hoping for the self-censoring model. That's where, for example, if you open two FTL wormholes too close together (which allows time-travel) it causes an energy-feedback in the quantum-foam (or... something) which destabilises the wormholes. This is the best solution because it means that FTL might still be possible, without the causation problems caused by FTL inherently leading to time-travel. Gives us the best of both worlds.
Zarpaulus,
"On George Dvorsky's article.
10. What is this even?"
Read up on Roko's Basilisk. It's stupid, but people have gotten themselves genuinely scared of it. To the point where even the mention of it is banned on Yudkowsky's philosophical discussion site LessWrong.
Re: 9 - Immortality imprisonment
If we've cracked immortality, then we can certainly come up with more effective punishments than prison (such as treatments or psychological behaviour blocks, "in group" exile or other rights restrictions (such as David's Probationers or Heinlein's Coventry), chip-in-the-brain behaviour modification, etc.)) Hell, if immortality/life-extension is so cheap/easy that we do it as a punishment, it will be widespread to the point of being a basic human right, so just threatening to take away immortality treatments would be a greater punishment than granting it. "You will be condemned to age ten years naturally." "Nooooo!"
Hi Paul
"Apparently they produce nitrous oxide, which acidifies the air, the rain, then the seas. If the GRB is close enough, it will produce enough to kill everything that isn't already acid tolerant, or isn't deeply hidden. So in theory you can reset a planet all the way back to extremophiles."
Its still a single hemisphere event
The way I understood it it produced enough Nitrous to zap the ozone layer
Which is completely different from enough to acidify the oceans
But even so
Lets say it did zap a ton of Nitrous on one hemisphere,
A lot of that would rain out long before it mixed with the atmosphere on the other side,
Then whats left would mix with the air from the other side
I could see such an event being really nasty on one hemisphere - and around the border to the other hemisphere
But away from there - a few hundred miles into the unaffected hemisphere??
By the time the nitrous had been blown a few hundred miles most of it would have been rained out so the effects on the other hemisphere would be minor
Even if you wiped one hemisphere and a good bit of another out that would not be a mass extinction event
Those are events with 80 or 90% of species wiped out
Wiping a hemisphere would cause less than a 50% (probably much less) extinction event
The reason its not IMHO such a big deal is because the events are such short time frame
The planet itself acts as a shield and the event is over in a few seconds
@Paul 451
Bond's mistake, IMO, is in focusing on Skylon. The only part he had was the heat exchange system, which is ideal for assisting jet engines (particularly high-speed supersonic jet engines, but it should improve the efficiency of regular old sub-sonic turbo-fan engines.)
If this was such an obvious market route, then why was it not developed by Rolls Royce who have the development and market expertise? While theoretically cooling the airflow makes sense for supersonic and hypersonic air breathing craft, the complexity may not make engineering or operational sense. Which may explain why the military route has not been successfully exploited by any engine or airframe manufacturer. It may only make commercial sense for space launchers. If the original heat exchanger idea was so useful, why did the UK government classify it but not exploit it? Hardly any sort of bargaining chip.
The space business is still primarily commercial comsats, government/military satellites, plus an icing of ISS crew and supply ferrying. Given the large public funding for the latter 2, SpaceX is pursuing those markets as a way to fund development. Like REL, SpaceX is pursuing the reusability approach, but with more conventional technology and without SSTO aspirations. If they can pull it off, then they will likely become market leaders. Skylon is aimed at the commercial satellite market and is clearly a more elegant solution if it can be made to work. But they will be trying to crack SpaceX's market by the time they are ready fly, as well as other public and private competitors offering "high frequency flights".
Britain wants to build a public infrastructure spaceport, arguably coming late to the potential space tourism business, yet doesn't commit to supporting the UK space business with serious funding. 60 million pounds is just peanuts, barely 1/1000th of its military spending.
Gamma Ray Bursts - this BBC Horison script seems to suggest that GRBs are highly directional and would need to be quite close to cause an extinction event. That Earth has never experienced such an event large enough to wipe out all but microbial life, the risks must be assumed to be low. The extinction events we know about appear to be pinned to known events. Arxiv papers are not peer reviewed, so it would be a good idea to wait for the journal article to appear before accepting the authors' claims.
Duncan - I think your suggestion that the short time of the GRB allows the Earth to shield itself only applies if the damage is direct. The KT event was global because the impact, while quick, spread damage around the globe. You are assuming no such secondary events would occur with a GRB. Correct?
Loved Interstellar. There's some bad science- but marginal compared to most sci fi films.
In fact, I told one of my friends that "Interstellar is what would happen if David Brin rewrote 2001" - and I certainly don't mean that as a bad thing! It felt like a response to the inhuman prometheanism of 2001 and the solipsistic despair of Solaris.
It suffers from Nolan's usual over-indulgence, pacing problems and plot holes- but if you can get past that, it's a treat.
I'd be interested to hear what David has to say about what will happen to the ISS if the relationship between the U.S. and Russia continues to deteriorate.
Even if we can get our astronauts to the space station without Russian rockets, what happens if our two countries stop cooperating?
Hi Alex
Yes - there were no such secondary events in the paper
And the sheer amount of energy involved while huge is tiny compared to the KT event
1000Jk/m2, radius of earth 6371km
1.2 x 10-20Joules
KT object
20km radius, 25,000km3
25 x 10-15 kg
10km/sec
= 12.5 x10-23joules
So 10,000 times the energy
These are "back of envelope" calculations - If I have screwed up please let me know
I expect ISS cooperation will continue to the very "end" because it deeply suits both sides to have a "mature" side to use as contrast.
@Duncan "And the sheer amount of energy involved while huge is tiny compared to the KT event"
I think that is the key point. These GRBs will need to be quite close to do any serious harm (although I don't want to be outside at the time).
Conversely, while the KT event has been pinned as the likely proximate cause of the Cretaceous extinction, we do know of a number of large impacts that may or may not have contributed to other extinctions. This seems to put asteroid impactors as a much more dangerous phenomenon than GRBs. Of course a few seconds of intense GRB tomorrow could upset this opinion :)
If GRBs or other stellar phenomena are a big danger, the human race will need to develop star flight to ensure survival, although my guess is that as a species we will be long gone before Sol is a target.
It probably isn't the GRB or impactor that causes an actual mass extinction. An asteroid that is large enough or GRB that is close enough certainly could, but that should make them rare events.
From what I've read, it is the climate change that occurs after a smaller extinction that resets the slate. Life is directly involved in the balance of forces, so killing a large swath of it will have consequences later.
One thing to consider is that space is not two-dimensional. Nor do all planetary systems orbit on the same orbital plane that the Sol system does - which is a reason why we can get nifty pictures of star systems forming... and can't always rely on planets passing in front of their suns in order to find them.
So while a GRB could hit one side of a planet... it also could hit a polar region for the entire "northern" or "southern" hemisphere. Or it even could hit at an angle. Depending on the continents of the planet struck by a GRB, you might very well have the majority of it hit the ocean... or all of the land mass and thus cause problems for all land-dwelling animals.
Nor are all GRB two-second affairs. Ultralong GRB can last for thousands of seconds - or in other words several hours. Even a short-term GRB lasting but 10 seconds can result in compounds formed in the atmosphere that would be akin to an impact winter. Air patterns could distribute this across the globe, and given how long it takes for upper-atmosphere particles to be removed from the atmosphere, this impact could last for years or longer.
Also don't discount the impact that a hole in the ozone layer the size of half the planet would have. The remaining ozone wouldn't instantly disperse and fill the void, and chemicals formed in the upper atmosphere could continue to destroy ozone after the initial burst.
Rob H.
Speaking of the KT extinction...
... have you guys read about the global firestorm hypothesis?
Just saw 'Interstellar'. Very good. I can certainly nitpick (I mean, perfect place for NASA to have its underground meeting room: right next to the underground launchpad!) but was actually quite pleasantly surprised about how little I needed to tweak the filters. My real concern was the 'planet B' scenario depicted in the trailers, but it turns out there's an interesting contest there... Oh, and the robots are a nod to space adventures past (should be obvious, but I won't spoil it)
Roko's Basilisk (Bah-silisk?) is a variant of the insane Diety in BoR. An exercise in craven logic; the sort that causes Pettigrew to abase himself in front of the newly resurrected Voldemort because "Master has given me a new hand!"
Re: Interstellar
Saw an Imax screening of Interstellar last night. Plot holes large enough to drive a starship through without fear of spaghettification.
When I first saw the trailer many months ago, the film's premise left me baffled. 169 minutes of explication and special effects didn't shed any light. Though images of a decaying world and a civilization turning its collective back on science were haunting (and, post-election, prescient), it was laughable to imagine finding a colony world in any way more hospitable than the Earth -- at least our atmosphere, gravity and temperature are to our specs. Why we weren't building greenhouses, arcologies or underground bunkers instead of sending eggs to sterile worlds in the sky... Yes, it's just a movie. But a pretty silly one.
But if this is the best portrayal of a black hole, it wins in a small category against classics of cinema such as Disney's "The Black Hole", and this gem, also innovatively entitled "The Black Hole" (http://www.imdb.com/title/tt0433883/)
I would never be this harsh (making ANY movie is an incredible achievement, even a lousy one) except in reaction to Christopher Nolan fanboys (and fangirls) who insist this is a new classic of cinema, this generation's 2001, 9.1 rating on IMDB and so on. The man can clearly do no wrong. They are as effective and annoying as the moon landing deniers -- say it long enough and loud enough, and eventually the textbooks get changed.
Between 7 p.m. and 8:30 p.m. Eastern time Tuesday night, two major decision points will be reached in the Rosetta mission’s attempt to put the Philae lander onto the surface of a comet. Be sure to follow this epic event! Which will conclude on Wednesday around 11 am Eastern time (they hope.)
There will be coverage on SCI the science channel. Yay ESA and yay us.
http://www.washingtonpost.com/news/speaking-of-science/wp/2014/11/11/watch-the-historic-rosetta-comet-landing-live-starting-now/
onward!
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