Star Mission of a Lifetime

by Paul Gilster on November 28, 2006

We seem to have accepted in our time the notion that technology always moves forward. But a key factor in the Drake Equation, that long and interesting conjecture that parses the possibilities for extraterrestrial life, is the question of whether technological societies have an average lifetime. Do they invariably survive to reach the stars, or do they destroy themselves before this is possible?

Listen to something Fred Hoyle said back in 1964:

It has often been said, if the human species fails to make a go of it here on Earth, some other species will take over the running. In a sense of developing high intelligence, this is not correct. We have, or will have, exhausted the necessary physical prerequisites so far as this planet is concerned. With coal gone, oil gone, high-grade metallic ores gone, no species however competent can make the long climb from primitive conditions to high-level technology. This is a one-shot affair. If we fail, this planetary system fails so far as intelligence is concerned. The same is true of other planetary systems. On each of them, there will be one chance, and one chance only.

The reference is from Hoyle’s Of Men and Galaxies (Seattle: University of Washington Press), and I ran into it in Andrew Kennedy’s paper on ‘the wait calculation,’ which we’ve been discussing here recently. Hoyle’s take is controversial, to say the least, but it underlines the long-range issues we often focus on in these pages. Do we have the capacity, for example, to solve intractable problems over the course of centuries when this would involve sacrifice on the individual level during our comparatively short lifetimes?

Think long-term about interstellar missions and you see the limitation. In a recent presentation at Princeton, Marc Millis laid out the support levels that might be expected for various human ventures into the cosmos. A mission time of 3-5 years could attract the interest of power brokers in government and industry. A 20-year mission could still capture a significant portion of the populace. But by the time you hit 50 years — and these are the time frames being discussed for Kuiper Belt missions or missions to the gravity focus — your potential audience is reduced largely to the professionals involved.

Millis ponders these things because he is former head of NASA’s Breakthrough Propulsion Physics program and founding architect of the Tau Zero Foundation. And he knows that it has become all but axiomatic that a mission cannot be longer than the lifetime of the scientists who sent it. A 100-year long mission gains virtually no public interest (though still piquing the attention of the scientists most closely involved with the target in question). Mission times over 100 years become problematic in every way, requiring a societal commitment that we haven’t seen since the cathedrals of the Middle Ages or the pyramids of the Egyptian pharaohs. In both those eras, multi-generational projects were undertaken and brought to fruition because of a broader conception of man’s place in history than seems possible today.

On a visit to Marshall Space Flight Center, I once asked NASA’s Les Johnson whether society would ever send a 1000-year mission to another star. I was really asking about the social will to do such a thing, but Johnson took the question more practically. “I’d love a thousand years,” Johnson replied. He meant that we’re nowhere near having the capability of launching even a mission of that length, much less getting those numbers down to a few centuries.

So what are reasonable mission goals? Millis laid out some key numbers at Princeton that serve us well. Get to 6 percent of light speed and Centauri becomes feasible as a 76-year mission, while within 15 light years of Earth (and 265 years of flight time) are five systems that look intriguing from the perspective of habitable planets. Jump to 25 percent of light speed and Centauri is reachable in 22 years (no worse than the Voyagers’ continuing mission), with fully 20 other systems in range in a 100-year time frame.

What throws a wrench into the machinery? Three possibilities, one being the discovery of a nearer target (i.e., a brown dwarf closer than Centauri or something of that nature). Another is a physics breakthrough that dramatically changes mission times (Millis calls this ‘incessant obsolesence’). But the third is the one we seldom discuss: perhaps the pace of technology actually slows, and becomes longer than the actual mission time. At that point, there is no thought of waiting to launch, because no faster mission will get to the target first. In fact, the longer we wait, the worse the chances of ever launching.

If Hoyle is right, a major variable in all this is that technological growth may falter entirely, with terminal exhausion of a planet’s resources. Circle back to Fermi and you get a solution to the question ‘where are they’ that technology optimists like myself don’t like to consider. We don’t see extraterrestrials because technological societies are rare. And they’re rare because most such societies destroy themselves before star missions ever become viable. It’s a bleak assessment but something to ponder as we consider our ability to plan and carry out projects over the lifetimes not just of researchers but civilizations.

Zen Blade November 28, 2006 at 15:02

I was just wondering about something… If we had some sort “probe” or equipment, or something at Centauri, would there be a way to coordinate the equipment’s actions with the actions of similar equipment here on earth to do incredibly cool science? Or perhaps even help to scan the cosmos for intelligent life… or send signals to let ET’s know that we are out there?

sorry, if this seems stupid, just a post-lunch thought I had after reading the topic!
-Zen Blade

Administrator November 28, 2006 at 15:27

Good question, because we need to do something with that probe if we ever get it there. The trick in working with equipment on a Centauri planet or nearby space is the speed of light limitation. Even at Mars, it’s necessary to be incredibly careful with the rovers to make sure that the vehicle doesn’t do something damaging — and there we’re measuring round-trip signal time in mere minutes. So you can imagine how tricky it would be to control a device around Centauri from Earth. That’s why a true star probe is going to have to be autonomous in all its actions, able to process information and act on the results without asking any controllers back home.

On the other hand, even with that limitation, all kinds of interesting things do emerge, such as very long baseline astronomy. Very tricky to coordinate, of course, but (and this would be futuristic indeed) if we got the right communications gear in place and had a versatile enough probe on the scene, numerous things become possible beyond simply sending back raw data.

Adam November 28, 2006 at 18:01

Hi Paul

Perhaps interstellar probes should be made autonomous and self-replicating so that the mission will at least matter to them even if it all goes to hell at home.

Adam

Fr. Gregory November 28, 2006 at 19:16

Resources available to us are not limited to our home world. As we move into a Kardashev type 2 civilisation we can reasonably expect to exploit the resource potential of our own system as a launching point for the stars. We just have to try and ensure that we complete the first phase without wounding ourselves so mortally that the asteroids remain forever out of reach.

Kurt November 28, 2006 at 19:47

None of these doomsday explanations can account for the Fermi paradox because it only take one civilization to make it and the entire galaxy gets developed over a 10 million year period. If there’s ETs in our galaxy, the place ought to look like Shinjuku (in Tokyo). It doesn’t, which suggests to me that we are alone.

I know many of you here don’t like it, but I think the “Rare Earth” explanation has some validity to it. Also, it is the opinion of virtually every evolutionary biologist that the emergence of sentient intelligence is extremely rare (e.g. vision independently evolved no less than 40 times and sentient intelligence apparently evolved only once).

Occam’s battle ax: the galazy appears to be empty of intelligent life, hence we are alone.

Which brings up another point: Many people who are professionals or just interested in space seem to have a hang up with the idea that we are alone (at least in our galaxy). Once, in the 80′s, after I had just read the “Anthropic Principle”, I went to an L-5 Society party and brought up the point that we are probably alone in the galaxy. The reaction I received was like if I had pissed on a statue of the Virgin Mary in a Catholic church. They really did not like this idea, which suggested to me that ET and SETI are, psychologically speaking, like religion to many of the space advocates.

I have no problem with the idea that we are alone. We will eventually develop the technology to go to the stars, one way or another. If we’re alone, it simply means that all of that lovely real estate is ours. Like having the American frontier but without the native Americans. You can’t ask for anything better.

Zen Blade November 28, 2006 at 20:47

Kurt,

“sentient intelligence apparently evolved only once” –first, depends on your definition of sentient. Check out wikipedia and their discussion about sentience. But, understanding your point… what I think you mean is a species that is able to make tools, adapt, and expand its knowledge in creative ways leading to technology and technological progress. The reality is many sorts of animals, largely mammals but not only mammals can AND DO use “tools” to either protect themselves –gorillas using sticks to gauge water depth of a river–, to get food (most common), or to attract mates. Many animals MAY lack the ability to innovate on a regular basis, but many can immitate…
Man’s leap into technology was relatively recent and many inventions such as writing– the maintaining of trade records?– appear to be intimantly linked to the needs (for early humans) associated with population density.

I wonder whether the concept of “ambition” or “drive” or even “progress” is the real culprit behind man’s rise. I point this out only because there are still humans across this planet that are living with no modern technology. These individuals are just as brilliant and emotion-filled as we are, but technology is something they have never needed or felt the need for. sorry, I got distracted. :)

Regarding intelligent life in the galaxy:
The problem I have with saying “we don’t see any signs of intelligent life, therefore there is none” is that it’s negative data. It’s like trying to prove God doesn’t exist. I’m sure there are people here who know what signs we should be looking for, but I often wonder if we really know what a galaxy filled with intelligent life would truly look like. I certainly don’t

Personally, I think it would be cool to find other intelligences, much like it’s cool to travel abroad or talk to people from other countries. And very much like it would be cool to travel different solar systems seeing things I’ve never seen before.

-Zen Blade

Adam November 29, 2006 at 5:24

Hi All

The ‘Rare Earth’ concept has merit, but civilisations need only to be rare and short-lived, not non-existent, to remain unobserved. Of course that scenario’s even gloomier than being Alone.

Personally I think They’re already here in our Kuiper Belt, but the only way to know for sure is to go look.

Adam

Icelander November 29, 2006 at 9:05

If a technological civilization sprouted at the end of the Cretaceous period, complete with superhighways and SUVs and suburbs and other things not necessarily starting with ‘s,’ could we know about it? The best estimates is that all traces of human habitation of this planet will be gone after about ten million years.

The oil isn’t “gone,” the coal isn’t “gone” and the metallic ores aren’t “gone.” They’re merely redistributed. What if the oil fields we’re harvesting are simply the “central Floridas” of millions of years ago? Coal seams are merely crunchy peat bogs. And what if the iron and other deposits are merely the trash dumps of a super-ancient species?

It took the earth about five billion years to go from a lump of molten rock to having this technological civilization. It’s not out of the realm of possibility that the earth could go from our extinction in the next ten thousand years to the rise of another technologically advanced species in a billion years.

Also, as materials become more rare and access to space becomes cheaper, there will eventually be companies mining places like Mars, the Moon and the asteroid belt. There are huge reserves of untapped resources out there. Enough, it has been estimated, to sustain a hundred billion humans in this solar system alone at current first-world standards of living.

I’m not too concerned if we’re the only (or merely the first) spacefaring species in the galaxy. I am concerned that we’re not taking that possibility seriously enough to stop doing all the destructive things we’re doing.

Paul Dietz November 29, 2006 at 11:42

If a technological civilization sprouted at the end of the Cretaceous period, complete with superhighways and SUVs and suburbs and other things not necessarily starting with ’s,’ could we know about it?

Absollutely! Many of the resources we are currently exploiting are much older than this. Many coal beds, for example (although many of those may have been too deeply buried eariler.)

244Pu from nuclear activities would easily survive from the end of the Cretaceous (halflife: 82 million years). This was the isotope used to rule out a nearby type-II supernova as the cause of the K/T extinction.

Fossilized oil wells (with their oxidized casing) should be recognizable even after geological ages have passed.

philw November 29, 2006 at 14:27

None of these doomsday explanations can account for the Fermi paradox because it only take one civilization to make it and the entire galaxy gets developed over a 10 million year period. If there’s ETs in our galaxy, the place ought to look like Shinjuku (in Tokyo). It doesn’t, which suggests to me that we are alone.

I know many of you here don’t like it, but I think the “Rare Earth” explanation has some validity to it. Also, it is the opinion of virtually every evolutionary biologist that the emergence of sentient intelligence is extremely rare (e.g. vision independently evolved no less than 40 times and sentient intelligence apparently evolved only once).

Occam’s battle ax: the galazy appears to be empty of intelligent life, hence we are alone.

Which brings up another point: Many people who are professionals or just interested in space seem to have a hang up with the idea that we are alone (at least in our galaxy). Once, in the 80’s, after I had just read the “Anthropic Principle”, I went to an L-5 Society party and brought up the point that we are probably alone in the galaxy. The reaction I received was like if I had pissed on a statue of the Virgin Mary in a Catholic church. They really did not like this idea, which suggested to me that ET and SETI are, psychologically speaking, like religion to many of the space advocates.
*********
Well said. I agree and have experienced the same fundamental hostility to the idea that the simplest answer based on what we know (vs believe) is that we’re alone. It seems to be a tenet of ‘faith’ by space cadets that we’re one of many tech societies in this galaxy. Most of the folks argue from the “billions and billions” fallacy standpoint. The # of stars is so big that there MUST be other tech civs. A non-sequitor.

Right now we have no evidence that even basic life was not a 1 time 10 exp minus 30 fluke, an arguement from some biologists (I think it’s wrong, but that’s opinion, not fact) and certainly there’s no evidence of the evolution of other math facile species on the Earth. Intelligence is likely rare. And the emergence of a subsequent technological society might require evolutionary cultural quirks not often expressed in other thinking capable biologics, if there are any.

Most of the ‘explanations’ of the Fermi Paradox fail because only ONE species needs to bypass the given postulate in order to populate the galaxy.

hiro November 29, 2006 at 14:41

It depends on some situation when we define “ET”. What if there really exists an earth-like planet where bug-like creatures live in our galaxy? We cant even communicate with bugs on Earth can we? I think that we are talking about advanced ETs, not simple life forms. There is also a possibility that our signals passed through ETs who were still in stone age.

Zen Blade November 30, 2006 at 0:00

I still wonder what we would see if the galaxy was full of life… I mean, seriously, if we don’t know what to look for, then can we really say the Fermi Paradox is applicable to the current galactic environment?

I’m not questioning the wisdom of the Paradox, merely the assumption that since we see “no signs” there must not be intelligence out there. Define the signs that we would expect to see. I still don’t know what those signs are short of an emissary visiting us… and I don’t see any reason to assume that an Advanced Civ. would necessarily want to go and visit other intelligent life.

-Zen Blade

ljk November 30, 2006 at 5:27

Type 3 Civ: “Isn’t it just so precious when an infant
species that has barely stirred from its crib looks around
and not finding itself doted upon by the rest of the Universe,
automatically assumes it has the whole place to itself?”

I think it has a lot more to do with humans not wanting
there to be anyone else who might want to play with the
same toys in the room. Or that the other occupants may
not want to play nice at all. They’re still recovering from
centuries of invasion, conquest, and tribal warfare.

Still thinking that everyone else will think and act like
humans, or even typical Earth life forms. What if other
species learned that cooperation was the best way to go
from the start? What if humanity is the equivalent of the
invading alien conquering the galaxy, not the other way
around?

We’ve gone from being burned at the stake for even
suggesting that other worlds exist with life to a brief
flowering period of optimism, then to pessimism that
either alien life exists or that if it does, it has nothing
good planned for us. Anyone in the middle on this
issue, or is ET life thinking just another victim of the
extreme polarized attitudes so prevalent today?

And stop confusing religious feelings about the Universe
with actual religion. Normal human beings are emotional
creatures and they are naturally going to have a sense
of wonder and awe about such grand concepts as ETI and
the Cosmos itself.

Scientists and scientist types like to pretend they are above
such base displays, that they can coldly and objectively talk
and think about such concepts and not be stirred by them.
But when no one is looking, they get excited and wonderous,
too. They just don’t like it when guys like Carl Sagan actually
show emotion and subjectivity about something so major. Then
they wonder why the general public doesn’t get as enthused as
they and think that all scientists are socially immature geeks.

http://www.projectrho.com/rocket/pogo.jpg

Adam November 30, 2006 at 16:30

Hi All

Nice reply, Larry. OTOH the Fermi Paradox might be telling us something important – that we’re within a few million years of being the first potentially Galaxy-spanning civilisation. That’s a big responsibility and maybe we should contemplate that prospect for a bit. After all someone has to be first.

Adam

Administrator November 30, 2006 at 16:39

Adam, that’s an interesting possibility indeed!

Icelander November 30, 2006 at 17:20

Okay, so we might be able to detect them. (So long as their oil wells and nuclear storage sites are on sites that are currently able to be excavated and explored.)

However, would their existence preclude our existence? Yes, our coal beds are older than the Cretaceous, but could they have harvested the coal beds? Or would coal that old be useful in its super-ancient state?

Stephen November 30, 2006 at 19:48

So, we haven’t done any 100+ year long projects since the pyramids and cathedrals. So, it’s a psychological thing, right? That can be fixed. Uhm, let me see… sure, i’ve got it. Bring back slavery (or virtual slavery).

At the moment, i’ve not seen a good argument for the existence of God. But there is a pretty good argument arguing that God is unlikely. It goes like this: If spontaneous generation of self replecating molecules is unlikely, how unlikely is the spontaneous generation of a perfectly wise, all powerful being? To me, it makes more sense to believe in a free lunch Universe.

hiro December 1, 2006 at 14:59

Ouch, that’s hurt. The problem is that i fail to see how one can bend the logic of the universe like 1+2=10. If god really exists, s/he can do impossible things right?

Paul Dietz December 5, 2006 at 14:45

So, we haven’t done any 100+ year long projects since the pyramids and cathedrals. So, it’s a psychological thing, right?

Or an economic thing. During our last few centuries of sustained economic growth, the ROI available made real interest rates too high to justify projects with very extended paybacks. Maybe once economic growth plateaus and interest rates fall to very low levels we’d see an uptick in such long term projects.

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