Notes & Queries 4/28/10

by Paul Gilster on April 28, 2010

Solar Sail Symposium in July

The 2nd International Symposium on Solar Sailing (ISSS 2010) draws closer, the event occurring July 20-22 at New York City College of Technology of the City University of New York. The focus will be on recent advances in solar sailing technologies and near-term solar sailing missions, with coverage of hardware, enabling technologies, concepts, designs, dynamics, navigation, control, modeling and mission applications and programs. The deadline for abstracts is May 15, 2010, with full information available at the symposium’s Web site.

Image: The IKAROS hybrid sail concept. A solar sail gathers sunlight as propulsion by means of a large membrane while a solar “power” sail gets electricity from thin film solar cells on the membrane in addition to acceleration by solar radiation. What’s more, if the ion-propulsion engines with high specific impulse are driven by such solar cells, it can become a “hybrid” engine that is combined with photon acceleration to realize fuel-effective and flexible missions. Credit: JAXA.

Given that CUNY is the home turf of solar sail experts Greg Matloff and Roman Kezerashvili, the conference should become the epicenter for current analysis of these technologies. The major space agencies are strapped for cash, but a robust solar sail literature continues to flourish and interesting mission concepts are under development at the Japanese space agency JAXA, where a demonstrator hybrid solar sail/solar cell mission is being readied for launch on May 18, and at The Planetary Society, whose LightSail-1 may fly later this year.

Surviving Technological Adolescence

I love Philip Morrison’s statement that ‘SETI is the archaeology of the future,’ quoted by Jill Tarter in a recent opinion piece on CNN. Archaeology is all about the past, and the targeted beacon we might detect from a civilization a thousand light years away would have information about its past, not its present state. So while the information would not be up to date, it would be deeply informative, telling us by example that at least one civilization had lived long enough to survive the danger of self-destruction by means of its own technology, or at least long enough to send the signal.

The longevity of a technological civilization is the crucial factor in so much of this discussion. Give it a high value and the chances are that any civilization we encounter will be older than our own. That concerned Stephen Hawking enough to worry about what a powerful, nomadic culture might do to a life-bearing world it encountered. The other side of the coin is what Tarter suggests, that longevity brings with it a measure of wisdom. Suppose we make not just electromagnetic contact but actually encounter an alien culture in our own system:

Well, one thing is for sure: If they can get here, then their technology is superior to ours, and not just by a little! Arthur C. Clarke’s third law is, “Any sufficiently advanced technology will be indistinguishable from magic.”

Can we be certain that their magic would do us harm? I would hope that Hawking would agree that a large value for L (a requirement for that magical, star-spanning technology) could also mean that their distant civilization had found a way to stabilize itself in order to survive and grow old. That might require outgrowing any aggressive and belligerent tendencies that may have characterized their youth.

Paul Davies makes much the same case in an essay this morning via the Wall Street Journal, although Davies is more emphatic:

…suppose by some fluke aliens did come to visit Earth in the near future, then comparisons with Columbus are in any case wide of the mark, and reflect the rampant anthropocentrism that pervades much speculation about alien life. Just because we go around wiping out our competitors doesn’t mean aliens would do the same. A civilization that has endured for millions of years would have overcome any aggressive tendencies, and may well have genetically engineered its species for harmonious living. Any truly bellicose alien species would either have wiped itself out long ago, or already taken over the galaxy.

I prefer Jill Tarter’s approach, which notes that an advanced society might have to outgrow its aggressive tendencies to survive. Davies takes that conjecture and elevates it to a principle: “A civilization that has endured for millions of years would have overcome any aggressive tendencies…” Perhaps. But we’ve never encountered such a civilization, and have no way of knowing how it would behave.

Tarter is careful to note that the SETI Institute isn’t involved in broadcasting messages, but in listening to the universe to learn what might be out there, adding “If signals are detected, everyone on the planet should have a voice in deciding how to respond.” That assumes, of course, that we pick up a targeted transmission rather than extraneous signals from a civilization merely going about its business. The latter case still leaves the question open: Inform another intelligent species of our existence, or continue to listen and learn?

A Wanderer in the Oort Cloud?

How to explain odd, detached Kuiper Belt objects like Sedna? One way is through a large object perturbing the Oort Cloud, a possibility examined in a new paper by John Matese and Daniel Whitmire (University of Louisiana at Lafayette). The duo have been working for some years now on comet dynamics, in particular on the orbital parameters of ‘new’ Oort cloud comets, ‘new’ being understood as first-time entrants into the inner planetary region. It turns out an anomalous pattern exists here that can be explained by an Oort Cloud giant planet.

Because we have no detection from IRAS or 2MASS data, we can place a limit on the possible mass and present distance of this object. If it exists, the world the authors call Tyche (the good sister of Nemesis) is between one and four Jupiter masses and orbits in the innermost region of the outer Oort Cloud. The optimum wavelength for detecting the putative planet is in the 5-micron region, well within the limits of the WISE infrared survey, and the new paper suggests just where WISE might look.

The paper, submitted to Icarus, is Matese and Whitmire, “Persistent Evidence of a Jovian Mass Solar Companion in the Oort Cloud” (preprint).

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{ 21 comments }

Eric April 28, 2010 at 11:31

I found this particularly interesting:

“A civilization that has endured for millions of years would have overcome any aggressive tendencies…” Perhaps.

(Quote in original).

I am an archaeologist and am interested in evolutionary biology. I find nothing in these domains that make me as optimistic as Tarter or Davies about the peaceful nature of ETIs.

Just as Davies point about Hawking’s anthropocentrism misses the point. One could just as easily attack Carter and Davies for psychological projection in hoping for aliens that are “wiser” and more advanced along a path of moral and ethical development that align with their particular values.

Long-lived or sustainable does not necessarily require non-aggressive or altruistic. Even a non-aggressive act could be very damaging to us. Imagine they Encyclopedia Galactica writters typical of many SETI discussions. Even a society solely dedicated to obtaining knowledge may decide that the best way to acquire such knowledge would be to send out nanorobots to dis-assemble and digitize whole worlds to gain a complete picture of all biological and psychological states, not to mention a complete archaeological, fossil and geological record. Then they can run these biospheres as simulations and try out different parameters to see how these develop.

Davies and Tarter are no more or less biased than Hawking in all of this. We really don’t have any good way to establish constraints on the behavior and motivations of your “typical alien”. Evolutionary biology, game theory, and complexity theory may help, but so far, we can only have the most vague idea of how alien societies may be shaped.

However, I really think this is an important discussion and not just idle speculation. I think it far more likely that we’ll encounter home-grown aliens in the form of Artificial Intelligences. This scenario seems more urgent than direct encounters with extraterrestrials. Nevertheless, thinking seriously about motivations and behaviors of potentially very powerful intellects may be an important point of survival. Arguably, the Singularity may be near, at least it is more likely to be near than the nearest ETI.

And if a Singularity has say a 1 in a 100 chance of happening during the next 100 years, it is well worth the effort to think about how minds radically different than our own may act.

kurt9 April 28, 2010 at 12:17

I think it wishful thinking to presume that any civilization more advanced than us will have “outgrown” their aggressive tendencies and have become peaceful. I see no reason to believe this. Aggressiveness may be natural, given that life itself is inherently expansionist and that it does evolve to fit into unfilled niches.

Tim April 28, 2010 at 12:37

“…A civilization that has endured for millions of years would have overcome any aggressive tendencies, and may well have genetically engineered its species for harmonious living….”
An interesting point; but, consider that each time I weed my garden, or walk in the bush, I destroy several types of living beings even though I have no “aggressive tendencies” while doing so. Similarly, alien beings that have evolved in alien environment for many millions of years may simply not recognize homo sapient as an important, or even a relevant life form!

Tim April 28, 2010 at 12:41

In the above, “homo sapient” should read “homo sapiens”.

Darrell E April 28, 2010 at 13:04

Jill Tarter said:

… could also mean that their distant civilization had found a way to stabilize itself in order to survive and grow old. That might require outgrowing any aggressive and belligerent tendencies that may have characterized their youth.

It is refreshing to see someone in this debate expressing some degree of tentativeness about their ideas. Not only are there certain to be many ways in which stability over long periods of time does not require a civilization with no aggresive or belligerent tendencies, there is also no reason that a civilization could not, after a very long period of peace and stability, change.

Paul Davies said:

A civilization that has endured for millions of years would have overcome any aggressive tendencies, and may well have genetically engineered its species for harmonious living. Any truly bellicose alien species would either have wiped itself out long ago, or already taken over the galaxy.

I am coming to think of this kind of sureness about some characteristic of advanced alien civilizations as some kind of logical phallacy. This is pure speculation, with homeopathic levels of data to work with.

I am not attempting to support Professor Hawkings views, I don’t see how we can determine if his views are more probably correct than Paul Davies views. My position is that we have no way to assign probabilities, that are worth serious consideration anyway, to any of the multitude of ideas that people have come up with about what an advanced alien civilization might be like, so don’t get too attached to any one idea. You are almost surely fooling yourself if you believe you know what an alien civilization must be like.

I don’t think that we shouldn’t speculate about these things though. Speculation is fun, and can be very useful.

Duncan Ivry April 28, 2010 at 13:55

“… their distant civilization had found a way to stabilize itself in order to survive and grow old. That might require outgrowing any aggressive and belligerent tendencies that may have characterized their youth.”

This is naive. Nature around us — the whole universe — is a dangerous place even without intelligent species. A certain amount of aggression is neccessary for surviving. Outgrowing any aggressive tendencies may imply not being able to withstand nature, which in turn may imply passing away as a species in the long run. Aggression is negative *and* positive, and a certain amount of aggression is necessary for a civilization “to stabilize itself in order to survive and grow old”.

andy April 28, 2010 at 14:06

Among all this discussion of SETI/METI, has anyone here read Blindsight by Peter Watts? It’s quite good at portraying very alien forms of intelligence and has lots of musings about the nature of consciousness. Plus, vampires in space!!!

Even better, it’s available online under a Creative Commons license here.

NS April 28, 2010 at 14:44

You can imagine a scenario where early in its history an intelligent species had to battle another intelligence for survival. Such a species might be very benign and cooperative toward its own kind but have a poisonous fear and hatred of any other intelligence.

Eric April 28, 2010 at 17:19

@andy

Great book!

Love how our style of intelligence and conscious experience is a maladaptive epiphenomenon. That, a nearby Brown Dwarf, and radio leakage from Earth interpreted as ineffective memetic/computer virus attacks. What more can you want?

Joel April 28, 2010 at 18:08

Let’s assume that contact is a two-way street and not merely the ETs acting upon earth. In such a case, the nature of the contact will reflect the behavior of both species. We humans, often a violent and territorial species, will no doubt color the interchange, whether the alien species is wisely benevolent or not.

Bounty April 28, 2010 at 18:37

Judging by our exoplanet endevours, and given they have better tech, they probably alreay know life is here. After years of sending signals, we never replied, so they assumed it’s safe to colonize. Ship’s on it’s way. Now we’ll have to fight for resources when they get here. Damn, if only we had setup a beacon!

kzb April 29, 2010 at 7:40

Anyone who has read Greg Bear’s Anvil of the Gods will realise there could be one very good reason why SETI projects do not detect anything, and that is any civilisation that does not hide its presence quickly gets destroyed.

iainb April 29, 2010 at 12:32

There are so many contradictory perspectives in this thread and yet most seem eminently reasonable – pretty much underscoring Darrell E’s point that tentative speculation about the nature of ETI is probably about the best we can hope for, at least for now.

However, it makes the remote possibility of contact seem somewhat alarming to me. Would we as a species be even capable of a collective response to a signal detection? Similarly, would an alien species? Paul Davies in The Eerie Silence suggests that authorities should keep the source location secret until the first collective response is sent (Davies seems to think he would be a good choice for writing it), with a warning to the aliens that what will likely follow in its wake will be the interstellar equivalent of spam mail. Davies himself admits that may be very difficult to pull off.

However, it seems to me that even a highly advanced ETI might be as diverse in its spectrum of opinion as our own species, with all kinds of special-interest groups transmitting messages, from the benign to the frightening. That might make first contact an enormously chaotic and messy affair, exchanging signals on everything from physics and religion to Hollywood blockbusters and Doritos ads, and the ETI’s motivations and values – as our own – might be near-impossible to interpret.

kurt9 April 29, 2010 at 14:08

Yeah, I read Bear’s “Anvil of Stars”. Its one of his better writings. Its definitely grim.

Chris T April 29, 2010 at 15:49

*Sigh* This is an area where supposedly rational people seem happy to make unsupportable assertions with impunity.

Our knowledge base is zero and therefore all consequences are possible, including our annihilation. Until we can remove that consequence from the range of possibilities, contact would be unwise.

stephen April 29, 2010 at 16:06

I was thinking about the signal sent from Arecibo in 1974. The number of binary digits was the product of two prime numbers.

I wonder if anybody would send a similar signal as a 3-dimensional image, with even more information? The number of binary digits could be the product of 3 consecutive prime numbers–consecutive in a list of primes. Four dimensions or higher might be a possibility.

Aliens might decide they don’t want to hear from us until we can decipher their signal.

Base 2 numbers seems like such an obvious choice. But is it plausible that aliens might choose base 3, base pi, or base e? It might be a test of our intelligence and cleverness.

Matt April 29, 2010 at 23:58

Why should any civilization be all one thing or another? Except for the improbable case of a science fictional “hive mind” where the mind can stay together over interstellar distances, any other intelligent species we encounter is going to be composed of individuals. Those individuals are going to be, well, individual. I’m sure there will be individuals who question whether we’re intelligent, or who want to exploit us, just as there will be individuals interested in trade or the arts.

Moreover, the idea of a civilization as an entity-in-itself, capable of destroying itself, betrays a lack of basic understanding of history. During the Cold War, for example, the leaders of the United States and the Soviet Union were the ones with the power to destroy the world–not the people, not the countries, but the few oligarchs who ruled. Even global warming, which is a better example, is not an especially serious long-term threat to human civilization, because the economic processes continually drive industry to do more with less–oil is cleaner burning than coal, just as coal is cleaner burning than wood. My grandchildren (I’m 20 right now) will laugh when they learn about our climate change hysterics–their power will come from space-based solar, various fuel cells, fission and fusion.

A civilization can no more be wise than an apple curious. Wisdom and foolishness are both individual and subjective. Is it wisdom to devote your life to the advancement of science? Is it still wise when you take no joy from it and are better at the law?

“Any truly bellicose alien species would either have wiped itself out long ago, or already taken over the galaxy.”

This sort of “reasoning” has never made any sense to me. Traveling at c across the galaxy takes 100,000 years. A civilization that reached Type II 100,000 years ago and had a government interested in conquering the galaxy they wouldn’t be anywhere near us.

Martin April 30, 2010 at 5:07

Everyone just seems to assume that we (the humanity) are to be seen as intelligent. Though it might be hard for geocentric’s to understand, alien life can be as advanced to us as we are to ants.
All this talk always assumes the aliens are just like us only a little(?) more advanced. They might not give a damn about the 56th million solar system with nuclear power they found the last century. Except that the local void were in has a property they need for fast travel…

Mpilot May 2, 2010 at 14:07

I think what’s getting lost in all the conjecture is that we really have no way of knowing what an alien intelligence, evolved under (possibly) unthinkable conditions, would be like.

Could they be peaceful amongst themselves but fiercely xenophobic? Would they be interested in cooperatively sharing information? Or would they perhaps see us as a virus/eventual threat and do everything they can to wipe us out?

I think the assumption that an alien intelligence will be far more advanced than we are is fundamentally flawed. Sure, if they came here it stands to reason they would be *more* advanced (at least in propulsion) – but they might be more primitive in other ways.

We assume, for example, that all the conditions we need met for interstellar travel would apply to aliens. But who knows if they only need to eat once every ten years? Who knows if solar radiation that we need to shield ourselves from could actually be good for them? Weapons systems? Maybe their weapons are based on their unique physiology which might not even effect us. There are just too many questions to form an real assumptions. The only thing we really (should) know is how little we know.

Finally – what if they detected us, saw us as a threat, and had just enough tech to attach a propulsion/guidance system to a 100km wide asteroid and send it hurtling towards us? I believe that type of tech isn’t all that far off for us. If they had even a 500 year jump on us (technologically speaking) they would possibly have this kind of technology.

It’s definitely fun to ponder, and I hope to see *some* sort of resolution to the question of whether or not we’re alone answered in my lifetime. But sadly, for now, all we have is conjecture.

kzb May 4, 2010 at 7:51

The effect of more technologically advanced cultures on more “primitive” ones is never good, even if there is no overt beligerence. Think australian aboriginals or american Indians. (OK there was overt beligerence with the latter example but not for a long time now.)

If you have not read ‘Anvil of Stars’ by Greg Bear, please do, I think it should be “required reading” for people on here. Do not be put off by Bear’s more pretentious works, this one is a good read.

Finally, can I ask -what are the protocols if and when a SETI signal is found ? Does it have to be kept secret and referred to a government department ? Exactly what is the procedure for releasing the news in the public domain?

Administrator May 4, 2010 at 10:08

kzb writes:

Finally, can I ask -what are the protocols if and when a SETI signal is found ? Does it have to be kept secret and referred to a government department ? Exactly what is the procedure for releasing the news in the public domain?

Your question inspired the May 4 post, now available here:

http://www.centauri-dreams.org/?p=12345

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