# Leaving The Solar System

#### steve_bank

##### Diabetic retinopathy and poor eyesight. Typos ...
Open for discussion, what are the odds pf leaving the solar system? I don’t see it happening without entirely new science.

Issues

1. Energy

The show stopper. Energy density and mass.

2. Life Support

The Laws Of Thermodynamics would seem to say resources like O2, H20, and human waste can not be recycled indefinitely.

3. Gravity

Constant 1g acceleration may solve that, but then in comes energy consumption. As velocity increases at 1g distance per second goes up and the work goes up. The ISS has demonstrated long term physilogical changes with zero/low g.

4. Heat

How do you get rid of heat? The oly means is radiation. Mass goes up for radiators along with energy.

5. Psychology

What happens to a crew spending a long time in deep space with no Earth to look down at? Boredom. No variation in people. How long before a social meltdown?

6. Maneuvering

Deep space is not necessarily empty. There can be dust, gas, and objects. At say .5C how do you turn or slow down quickly? There will be reaction forces on the structure and on people. Any high speed gas and dust are abrasive. I saw a piture of a micrometeroite strike on a shuttle window. It looked like heat vaporized a neat hole in the window, not deep enough to penetrtae all the way..

7. Stopping at a destination

All the kinetic energy gained has to be lost and that will be heat.

Last but not least how do you now where you are at any time to what accurcay in going to a point in space, given that all obseved refernces are in motion. Again, accuracy required ad attainable.

9. The X Factor

I believe the term came out of Edwards during the breaking of the sound barrier. Despite thorough plann9ng and analysis there may be unknown variables. X in algebra usually representing the unknown to be solved for.

I coded somethin so I could look at plots or velocity, mass, time, and energy.

For constant acceleration dv = a*dt, change in velocity. Change in velocity is linear with time.

For Newtonian mechanics there are two ways to calculate energy. Assumptions are fuel with zero mass And 100% engine efficency.

Using work F = 1kg * a, Ework is F*Distance. For a straight line Ework is F*meters, Joules. If not a line then the it requires the work integral. ∫F∙dl.

The other is equating kinetic energy added to energy used, assuming 100% efficiency.

Tje two methods correlate. For 1g acceleration over 1000 days 357.75 peta Joules kinetic enrgy vs 357.39 work. Peta is 10^15. Compare to yearly energy in Joules for the USA.

https://en.wikipedia.org/wiki/Energy_in_the_United_States

Coded in Scilab, it can be ported to other tools or implemented as a spreadsheet macro, or a graphing calculator.

Relativistic mass is calculated vs velocity to see where it may become a factor, if any. It looks like up to around .5C relativistic mass if it applies is not a factor. The time step is 1 day, a shorter step will increase the calculated peak relativistic mass.

Feel free to pick it apart.

clear
light_year = 9.5e12 //km
C = 3e8 //m/s
a = 9.8 //1 g
Ndays = 1000
dt = 60*60*24 //seconds per day
dv = a*dt //change in velocity m/s
m0 = 1 //kg
F0 = m0*a // force Newtons
vel = 0
E0 = 0 // energy
Ew = 0 // work energy
s = 0 // distance meters
watts =(F0*dv)/dt //E/t Joules/second

for i = 1:Ndays

day(i) = i
dist(i) = s/1000 //km
ly(i) = dist(i)/light_year
v(i) = vel
ke(i) = E0 *(10^-15) //petajoules 10^15
we(i) = Ew *(10^-15)
ds = vel *dt // change in distance
s = s + ds
watts(i) =1e-6*(F0*ds)/dt
vel = vel + dv
E0 = .5*m0*(vel^2) //Joules
Ew = Ew + (F0*ds)
if(vel < C) // no divide by zero
mr(i) = m0/sqrt(1- (vel/C)^2); //m relative
mdif(i) = (mr(i)/m0)*100
else
mr(i) = 0;
end//if

pc_c(i) = (v(i)/C) * 100 // percent C

end//for

mprintf("ENERGY KINETIC PJ %.4f WORK %.4f\n",max(ke),max(we))

//mprintf("%e %f\n",v,pc_c)

Relative Nass

Speed Distance

Energy

#### rjh01

##### Member
One other problem. There will be collisions between tiny dust grains and the spacecraft. The energy of these dust grains, at this speed, is huge. They are also almost impossible to detect.

#### barbos

##### Contributor
The Laws Of Thermodynamics would seem to say resources like O2, H20, and human waste can not be recycled indefinitely.
No, they don't say that at all,
Earth has been recycling O2, H20 for hundreds of millions of years.

One other problem. There will be collisions between tiny dust grains and the spacecraft. The energy of these dust grains, at this speed, is huge. They are also almost impossible to detect.
Impossible? just put a flashlight in front of the ship and see reflection.

#### James Brown

##### Veteran Member
Humanity has been doing the impossible for thousands of years. Where there's a will, there's a way.

#### Elixir

##### Made in America
So the problem isn’t “leaving the solar system”, it’s getting anywhere else worth going to and arriving alive and well.

#### steve_bank

##### Diabetic retinopathy and poor eyesight. Typos ...
The old saying.."Wherever you go, there YOU are".

Why did the chicken cross the galaxy?

To get to the other side.

#### bilby

##### Fair dinkum thinkum
Your first issue is really the only issue. The distances are vast, so you're going to need more fuel than you can carry, and if you leave the fuel at home and send it to the spacecraft as photons, you're going to struggle to collect enough at the distances involved. This is a showstopper for crewed interstellar missions, and/or missions that take less than many generations of human lives to complete.

The rest of your problems really aren't problems at all.

A closed system can recycle everything indefinitely - that's the first law of thermodynamics. Entropy is a potential issue, but if you solved the fuel problem, that entropy problem goes away (fuel is, in essence, just a store of low entropy).

Rotation is a perfectly good source of gravity. So that's a simple engineering problem. Angular momentum is conserved, so it only requires energy when you turn it on or off.

Radiating heat from spacecraft is current technology. It's basically the same entropy issue already discussed. And deceleration is identical with acceleration; Typically the heat you're worrying about is in the reaction mass, not the spacecraft, which is why rockets don't burn up at launch. They risk burn up on re-entry, because they use aero-braking to avoid having to carry insane amounts of fuel - so that's yet another re-statement of your first point.

Humans already have remote outposts such as Amundsen-Scott base, and long duration submarine deployments, where small groups of selected and trained people live for months in isolation from the rest of humanity without psychological issues.

As you mentioned yourself, high speed debris is already an issue, and is mostly solved. It's also increasingly rare as you move away from the sun.

Stopping is the exact same problem as starting. It requires no new solutions. Energy is mostly carried away by the reaction mass, if you use a rocket.

Navigation is easy; General Relativity is very accurate, as are our observations of the universe. It's apparently difficult for you, but that's because you're still relying on Newton, and use ridiculous non-concepts (such as graphs showing what happens at more than 100% of c). Use the right equations, and the navigation is easily within the realms of existing technology.

You are right that it's probably impossible; But wrong about seven of eight of your reasons. Of course, you only need to be right about one.

And the X factor isn't a reason at all, it's a meaningless hunch. Certainly it would be difficult, even if we solved the energy problem. But difficult isn't impossible.

#### Loren Pechtel

##### Super Moderator
Staff member
I don't believe any of these are showstoppers.

There currently is one showstopper--given current human biological knowledge any interstellar voyage would be a generation ship. And while we see them in stories many times I do not believe a generation ship would ever be launched other than in dire need.

There is also the issue that for a colony to maintain our current tech level many millions of people are needed. While it would be possible to have a mission plan of simply not bringing many of the rare fields and only recovering them once the population has grown enough you have the problem that in regaining the fields it's entirely book learning--there's no teacher/mentor to tell you you're doing it wrong.

Once the biological side of things is solved (or rendered moot--I wouldn't be surprised if we end up doing immortality via upload rather than defeating aging) laser-pumped lightsail becomes mega-engineering but viable. During the midcourse period you leave the laser on at low power--just enough to counteract drag--and can use it as a power source.

By the time you have a ship large enough for the number of people you need to bring spin "gravity" is quite possible. I don't think this is a serious impediment.

#### Swammerdami

Staff member
Instead of a danger, could interstellar dust (and hydrogen atoms) be helpful? Scoop it up and use it as fuel, and for impulse mass.

#### steve_bank

##### Diabetic retinopathy and poor eyesight. Typos ...
Instead of a danger, could interstellar dust (and hydrogen atoms) be helpful? Scoop it up and use it as fuel, and for impulse mass.

Scoop it up at say 0.5C or even .1C?

Briningg mass even dust to the speed of the spaceship takes energy.

#### Swammerdami

Staff member
Instead of a danger, could interstellar dust (and hydrogen atoms) be helpful? Scoop it up and use it as fuel, and for impulse mass.

Scoop it up at say 0.5C or even .1C?

Briningg mass even dust to the speed of the spaceship takes energy.
Simplest, perhaps, is to think of things in the spaceship's frame, where the hydrogen would be contained (by a magnetic field?) and slowed down, and thus reduce the spaceship's forward momentum. It would be a winning idea only if you got more back (via the hydrogen fusion and impulse of ejected fusion product) than lost by capturing the hydrogen.

Would it work? I dunno.

Another idea, if there are lots of asteroids wandering around in interstellar space, would be to zig-zag among those asteroids, using them as gravitational slingshots. How massive would such an asteroid need to be to be a useful slingshot? A problem here (in addition to the probable lack of such asteroids) would be the very high g-forces needed to get a high velocity from the slingshotting.

#### James Brown

##### Veteran Member
Interstellar travel is often seen as a small cadre of people on a very fast ship, with all the attendant problems. But there are other ways that humanity can spread out to the galaxy.

One solution I've seen is more like an osmosis. Consider that our system is filled with asteroids. Some hardy pioneers land on an asteroid, set up solar and nuclear power, hollow out the interior, and spin up the asteroid's spin to accommodate human physiology. And they stay there for generations, harvesting water and minerals for export to the inner solar system.

Eventually population pressures compel some of the residents to make the next leap. Not to the nearest star, but to the nearest asteroid. Rinse and repeat. Over time (as in centuries) the logarithmic effects are such that humanity is spreading out in all directions. Progress continues until they reach the Oort cloud which reportedly stretches out to half the distance between Sol and Alpha Centauri, which presumably is surrounded by its own Oort cloud.

Thus humanity just takes one baby step after another from one star to another. To my mind, this mimics much of human migration on Earth. Yes, some peoples made large risky leaps, such as small flotillas migrating from one tiny Pacific island to another. But most human migration has been relatively slow steady spreads in search of resources.

The osmosis idea makes for less-compelling science fiction, but to my mind it seems more achievable.

#### Bomb#20

##### Contributor
Another idea, if there are lots of asteroids wandering around in interstellar space, would be to zig-zag among those asteroids, using them as gravitational slingshots. How massive would such an asteroid need to be to be a useful slingshot? A problem here (in addition to the probable lack of such asteroids) would be the very high g-forces needed to get a high velocity from the slingshotting.
In order to get a g-force out of it of even 1 g, an asteroid would have to have at least the mass of the Earth. (Except when you use lithobraking.)

#### steve_bank

##### Diabetic retinopathy and poor eyesight. Typos ...
I don't think the next step is a baby step. We are at the limits of science and engineering.

That being said, we have to consider entropy and the prohibition against perpetual motion.

To scoop up some form of energy the total energy gained has to be greater than the energy conversion process.

#### bilby

##### Fair dinkum thinkum
Instead of a danger, could interstellar dust (and hydrogen atoms) be helpful? Scoop it up and use it as fuel, and for impulse mass.

Scoop it up at say 0.5C or even .1C?

Briningg mass even dust to the speed of the spaceship takes energy.
This is discussed, with a number of possible solutions, in the Bussard ramjet Wikipedia page I linked in the post above yours.

It's also a neat solution to the problem of how to brake your spacecraft as you approach its destination.

#### Loren Pechtel

##### Super Moderator
Staff member
Instead of a danger, could interstellar dust (and hydrogen atoms) be helpful? Scoop it up and use it as fuel, and for impulse mass.

Scoop it up at say 0.5C or even .1C?

Briningg mass even dust to the speed of the spaceship takes energy.
Bussard ramjet has a theoretical limit of .12c and no doubt the practical limit is far lower if it even is possible.

#### Loren Pechtel

##### Super Moderator
Staff member
Eventually population pressures compel some of the residents to make the next leap. Not to the nearest star, but to the nearest asteroid. Rinse and repeat. Over time (as in centuries) the logarithmic effects are such that humanity is spreading out in all directions. Progress continues until they reach the Oort cloud which reportedly stretches out to half the distance between Sol and Alpha Centauri, which presumably is surrounded by its own Oort cloud.

Thus humanity just takes one baby step after another from one star to another. To my mind, this mimics much of human migration on Earth. Yes, some peoples made large risky leaps, such as small flotillas migrating from one tiny Pacific island to another. But most human migration has been relatively slow steady spreads in search of resources.

The osmosis idea makes for less-compelling science fiction, but to my mind it seems more achievable.

I believe the density of objects in interstellar space is too low for this to be viable.

#### lpetrich

##### Contributor
There are currently 5 spacecraft that are leaving the Solar System: Pioneers 10 and 11, Voyagers 1 and 2, and New Horizons.

has a complete list, including these five spacecraft and their upper booster-rocket stages.

All five spacecraft are powered by radioisotope thermoelectric generators (RTG's). They have some radioactive material whose decay heat is used to generate electricity using thermocouples. These use the Seebach effect, with heat flowing across a junction of different metals making electric-charge difference. This difference is then tapped for electricity to power the spacecraft.

Spacecraft familyMassRTG
Pioneer 10, 11260 kg155 W
Voyager 1, 2825.5 kg470 W
New Horizons478 kg245 W

RTG refers to the RTG electricity production at launch.

SpacecraftLaunchedDistVelIS VelLast Xmit
Pioneer 101972 Mar 10130.074 AU11.912 km/s (2.513 AU/yr)11.8 km/s (2.49 AU/yr)2003 Jan 23
Pioneer 111973 Apr 5108.265 AU11.192 km/s (2.361 AU/yr)11.1 km/s (2.34 AU/yr)1995 Nov 24
Voyager 11977 Sep 5155.006 AU16.951 km/s (3.576 AU/yr)16.9 km/s (3.57 AU/yrmid-2020's?
Voyager 21977 Aug 20128.938 AU15.304 km/s (3.228 AU/yr)15.2 km/s (3.21 AU/yr)mid-2020's?
New Horizons2006 Jan 1952.001 AU13.826 km/s (2.917 AU/yr)12.6 km/s (2.66 AU/yr)2030's?

Spacecraft escaping the Solar System

Last Xmit is the date of the last received transmission, or the possible future date of such a transmission.

What they visited:
SpacecraftVisited
Pioneer 10Jupiter
Pioneer 11Jupiter, Saturn
Voyager 1Jupiter, Saturn
Voyager 2Jupiter, Saturn, Uranus, Neptune
New HorizonsJupiter, Pluto, 486958 Arrokoth

#### lpetrich

##### Contributor
Booster rockets:
Spacecraft familyLaunch thrustBooster rocket
Pioneer 10, 118.4 MN D 37E
Voyager 1, 213 MN 37E
New Horizons12.3 MNB

MN = meganewtons. The Space Shuttle had a launch thrust of 30.25 MN, and the Saturn V 35.1 MN.

So it's hard to do much better than what we've done so far.

#### lpetrich

##### Contributor
I'll now estimate spacecraft mass / booster thrust ratios. Pioneer: 31 kg/MN, Voyager 64 kg/MN, New Horizons 39 kg/MN.

More large rocket thrusts: Soviet N1: 45.4 MN, Energia: 35 MN - American Saturn V 35.1 MN, Space Shuttle 30.25 MN, Falcon Heavy 19 MN - several similar-performance ones in development

A revived Saturn V could send about 2.2 metric tons into interstellar space, and that's a little more massive than the Mercury spacecraft, which the first American astronauts traveled in.

#### Swammerdami

Staff member
I've been reading this thread, because I need the answers to complete my sci-fi epic involving an intergalactic civilization.

I think that for acceleration from a star's planet I will use huge power generators that somehow project onto a departing star-ship's receptors. Assuming 1g acceleration we should get up to about 0.01 c by the distance of Saturn. (We won't need the power transmission too finely aimed; we'll build multiple power stations along the trajectory.)

Deceleration at destination will be easy with some sort of "magnetic parachute" or whatever it's called.

With 0.01 c we should be able to travel from one end of the Milky Way to the other in just several million years. And thoroughly explore the galaxy in about twice that time, assuming it takes 1000 years or so to set up a system's power stations.

Since the high-tech may require rare earths or uranium to "prime the pump," exploration convoys will maintain some radio contact and the ability to route some materials from one system to another as needed.

#### steve_bank

##### Diabetic retinopathy and poor eyesight. Typos ...
I've been reading this thread, because I need the answers to complete my sci-fi epic involving an intergalactic civilization.

I think that for acceleration from a star's planet I will use huge power generators that somehow project onto a departing star-ship's receptors. Assuming 1g acceleration we should get up to about 0.01 c by the distance of Saturn. (We won't need the power transmission too finely aimed; we'll build multiple power stations along the trajectory.)

Deceleration at destination will be easy with some sort of "magnetic parachute" or whatever it's called.

With 0.01 c we should be able to travel from one end of the Milky Way to the other in just several million years. And thoroughly explore the galaxy in about twice that time, assuming it takes 1000 years or so to set up a system's power stations.

Since the high-tech may require rare earths or uranium to "prime the pump," exploration convoys will maintain some radio contact and the ability to route some materials from one system to another as needed.
Nah. I like Herbert's Dune. After years of using a drug derived from the waste of giant sand tunneling worms people mutate to be able to mentally fold space between two points transporting ships quickly.

Or the Stargate TV showan intergalactic artificial star gate worm hole network. Togo to another galaxy quickly they used an FTL ship to place a chain of gates.

Heinlein used magnetic rail guns to launch back to Earth from the moon in Moon Is A Harsh Mistress, circa 1950s. How about a huge recoiless rail gun in space? I will license the idea to you for a percentage.

#### steve_bank

##### Diabetic retinopathy and poor eyesight. Typos ...
F = m*a

Acceleration in gs = (F/m)/9.8

#### Jimmy Higgins

##### Contributor
Humans already have remote outposts such as Amundsen-Scott base, and long duration submarine deployments, where small groups of selected and trained people live for months in isolation from the rest of humanity without psychological issues.
Humans have nothing like a generation ship set up on Earth. There is no control for future problems in the upcoming generations on a ship to be weeded out because they can't handle life in a capsule.

Regarding someone else's "baby steps", I think the biggest problem is money. There needs to be a return for this. While localized asteroids can be made profitable in one's imagination, the amount of money required to make an asteroid redundantly "habitable" enough for mining just seems "out of this world" high and unrecoverable. The only way to actually do it would be automated systems, which would be extravagantly expensive in its own right. So we wouldn't take baby steps to asteroids, robots would do it for us.

#### bilby

##### Fair dinkum thinkum
Humans have nothing like a generation ship set up on Earth
I disagree. The Austronesian people colonised the Pacific Ocean by this means and handled it just fine for three thousand years before the arrival of fast steamships and radio put a close to their isolated lifestyle.

There are still some small, isolated human groups with only a couple of hundred individuals.

The Sentinelese people of the Andaman Islands in the Indian Ocean are completely isolated from the rest of humanity, and some estimates put their population as low as fifty. They still retain sufficient sanity to understand that missionaries are best killed on sight.

Routine, rapid and efficient communications between tribes is a fairly recent phenomenon, and we have been doing it only for five or six millennia. before that, small isolated groups with infrequent contact with outsiders was the norm. It's what humans evolved with, so it's unlikely to be fatal to us in its own right.

#### skepticalbip

##### Contributor
I've been reading this thread, because I need the answers to complete my sci-fi epic involving an intergalactic civilization.

I think that for acceleration from a star's planet I will use huge power generators that somehow project onto a departing star-ship's receptors. Assuming 1g acceleration we should get up to about 0.01 c by the distance of Saturn. (We won't need the power transmission too finely aimed; we'll build multiple power stations along the trajectory.)

Deceleration at destination will be easy with some sort of "magnetic parachute" or whatever it's called.

With 0.01 c we should be able to travel from one end of the Milky Way to the other in just several million years. And thoroughly explore the galaxy in about twice that time, assuming it takes 1000 years or so to set up a system's power stations.

Since the high-tech may require rare earths or uranium to "prime the pump," exploration convoys will maintain some radio contact and the ability to route some materials from one system to another as needed.
You may be overthinking the "problem". There is no need to spell out details of how something works in a good sci-fi story. In fact, too many details can detract from the story. Just giving the ship's drive system a name should be quite sufficient... just call it the "Swammer drive" and move on with the important part of the story, the plot and character development. Let the reader imagine how that amazing Swammer Drive works.

For example, Arthur Clarke in his "foundation" series never bothered to explain how people got around the galaxy other than using 'atomics' in their ships. Roddenberry in his "Star Trek" series never explains how a transporter, food replicator, or warp drive works, what a phaser or photon torpedo was and how they worked, etc. and it didn't detract from the story line. We only know that "dilithium crystals" were needed for 'warp drive' to work likely because it was a plot device needed for one of the stories but what the 'dilithium crystals' do and how is never explained.

Last edited:

#### Jimmy Higgins

##### Contributor
Humans have nothing like a generation ship set up on Earth
I disagree. The Austronesian people colonised the Pacific Ocean by this means and handled it just fine for three thousand years before the arrival of fast steamships and radio put a close to their isolated lifestyle.
An island isn't outer space.
There are still some small, isolated human groups with only a couple of hundred individuals.

The Sentinelese people of the Andaman Islands in the Indian Ocean are completely isolated from the rest of humanity, and some estimates put their population as low as fifty. They still retain sufficient sanity to understand that missionaries are best killed on sight.
Isolation from people isn't as much the issue as isolation from the environment itself. Living in a tin can forever, we aren't exactly wired for that. And while we can choose who starts that process, the generations afterwards might not be able to handle it as well. Granted, it would be all they know, so possibly could work.

#### bilby

##### Fair dinkum thinkum
Humans have nothing like a generation ship set up on Earth
I disagree. The Austronesian people colonised the Pacific Ocean by this means and handled it just fine for three thousand years before the arrival of fast steamships and radio put a close to their isolated lifestyle.
An island isn't outer space.
There are still some small, isolated human groups with only a couple of hundred individuals.

The Sentinelese people of the Andaman Islands in the Indian Ocean are completely isolated from the rest of humanity, and some estimates put their population as low as fifty. They still retain sufficient sanity to understand that missionaries are best killed on sight.
Isolation from people isn't as much the issue as isolation from the environment itself. Living in a tin can forever, we aren't exactly wired for that. And while we can choose who starts that process, the generations afterwards might not be able to handle it as well. Granted, it would be all they know, so possibly could work.
Just because currently spacecraft are all 'tin cans' with no life other than the astronauts and perhaps a couple of experimental plants or animals, and no room to swing a cat even if one was brought along, doesn't mean that it will always be thus.

A generation ship would likely need an ecosystem, rather than a mere life support system - after all, that's how spaceship Earth has managed to support life for thousands of millions of years without a service call to the maintenance department.

A generation ship would have to have more in common with a remote island than with the International Space Station.

#### steve_bank

##### Diabetic retinopathy and poor eyesight. Typos ...
After many generations who knows what they would be like. Language woud chnage and probly loose a lot of words with nothing to reference outside the group and ship.

Earth would become a myth. New creation myth and religion would probably emerge. Without stimulus in a broader world I'd think overall intelligence woud decline. Limited life experiences and challenges.

#### Loren Pechtel

##### Super Moderator
Staff member
I've been reading this thread, because I need the answers to complete my sci-fi epic involving an intergalactic civilization.

I think that for acceleration from a star's planet I will use huge power generators that somehow project onto a departing star-ship's receptors. Assuming 1g acceleration we should get up to about 0.01 c by the distance of Saturn. (We won't need the power transmission too finely aimed; we'll build multiple power stations along the trajectory.)

Deceleration at destination will be easy with some sort of "magnetic parachute" or whatever it's called.

With 0.01 c we should be able to travel from one end of the Milky Way to the other in just several million years. And thoroughly explore the galaxy in about twice that time, assuming it takes 1000 years or so to set up a system's power stations.

Since the high-tech may require rare earths or uranium to "prime the pump," exploration convoys will maintain some radio contact and the ability to route some materials from one system to another as needed.

Unless there's something seriously range limiting about your power transmitters I wouldn't use that kind of acceleration--that's an awful lot of power to handle.

.01c is within what lightsails can do. Laser-pump the launch so they're down to .01c on arrival. (Although the exact amount a lightsail can slow down depends on the star. The bigger the star the more speed you can shed on the approach.) In theory you can go much faster, jettison most of your sail on approach and use it to bounce the beam back at what's left. However, that's something that requires incredible precision and has no room for error. (Read Rocheworld for some numbers. He was a hard sci-fi author, he took the time to get the numbers right. Interesting aliens but I can't imagine any of them actually evolving.) Note that if the destination already has a base you can go considerably faster with laser-pumped sails, you stop with a laser from the destination.

Note that there's nothing but information (note that people are basically bags of information) worth shipping across the stars. Interstellar trade will be only in information in any universe that must obey Newton and Einstein. Anything other than the equipment needed to bootstrap a new base is cheaper produced in situ. (With the exception of a situation where there is no in situ--for some reason you want to establish a base in the middle of nowhere.)

#### bilby

##### Fair dinkum thinkum
After many generations who knows what they would be like. Language woud chnage and probly loose a lot of words with nothing to reference outside the group and ship.

Earth would become a myth. New creation myth and religion would probably emerge. Without stimulus in a broader world I'd think overall intelligence woud decline. Limited life experiences and challenges.
Languages always change. You would barely understand Shakespeare (who spoke Early Modern English) if you went to visit him in your time machine; You would find Chaucer completely unintelligible unless you are a student of Middle English, and Old English has more in common with Modern Icelandic than it does with Modern English. Changing language is not to be feared, nor can it be stopped - and only an insanely conservative control freak would want it to stop.

Earth wouldn't become a myth unless your generation ship lacked a library, and an education system, or unless those things were manipulated to deliberately change the crew's perceptions.

Human knowledge tends to increase over time in all settings where records are easy to keep, and where scientific enquiry isn't deliberately suppressed.

Your opinions are apparently based on SciFi tales that were set on generation ships, but which you apparently didn't notice were actually cautionary tales of the danger of forgetting history. This is not something that's likely to occur due to isolation, it's something that needs to be guarded against politically regardless of how isolated a society might become.

#### Jimmy Higgins

##### Contributor
Humans have nothing like a generation ship set up on Earth
I disagree. The Austronesian people colonised the Pacific Ocean by this means and handled it just fine for three thousand years before the arrival of fast steamships and radio put a close to their isolated lifestyle.
An island isn't outer space.
There are still some small, isolated human groups with only a couple of hundred individuals.

The Sentinelese people of the Andaman Islands in the Indian Ocean are completely isolated from the rest of humanity, and some estimates put their population as low as fifty. They still retain sufficient sanity to understand that missionaries are best killed on sight.
Isolation from people isn't as much the issue as isolation from the environment itself. Living in a tin can forever, we aren't exactly wired for that. And while we can choose who starts that process, the generations afterwards might not be able to handle it as well. Granted, it would be all they know, so possibly could work.
Just because currently spacecraft are all 'tin cans' with no life other than the astronauts and perhaps a couple of experimental plants or animals, and no room to swing a cat even if one was brought along, doesn't mean that it will always be thus.
Which then leads to the next issue.
Generation Three said:
"Why are we doing this?! If we turn around now, we can get back to Earth quicker. We're so sick of eating sausage."
A generation ship would likely need an ecosystem, rather than a mere life support system - after all, that's how spaceship Earth has managed to support life for thousands of millions of years without a service call to the maintenance department.
My gawd... hogweed eventually becomes the sustainer of human life in space. The irony.
A generation ship would have to have more in common with a remote island than with the International Space Station.
I can't imagine how many generations we'll need to create a generation ship. In the end, a generation ship's benefit is limited. I mean, other than in the Wall-E sense of things. The commitment to the mission is tenable with each following generation. And I ponder just how large a crew is needed to make it work. The redundancy for the ship equipment would also be needed for the crew, engineers, doctors, mid-level accountants, justice, sanitation engineers, people that know why that blue button keeps blinking all the damn time, botanists, biologists, physicists, chemists, computer experts, someone that can fix musical instruments, educators, and one libertarian to fuck it all up. In general, novels and shows usually have one or two people do all of that stuff, but it isn't really possible.

#### bilby

##### Fair dinkum thinkum
Humans have nothing like a generation ship set up on Earth
I disagree. The Austronesian people colonised the Pacific Ocean by this means and handled it just fine for three thousand years before the arrival of fast steamships and radio put a close to their isolated lifestyle.
An island isn't outer space.
There are still some small, isolated human groups with only a couple of hundred individuals.

The Sentinelese people of the Andaman Islands in the Indian Ocean are completely isolated from the rest of humanity, and some estimates put their population as low as fifty. They still retain sufficient sanity to understand that missionaries are best killed on sight.
Isolation from people isn't as much the issue as isolation from the environment itself. Living in a tin can forever, we aren't exactly wired for that. And while we can choose who starts that process, the generations afterwards might not be able to handle it as well. Granted, it would be all they know, so possibly could work.
Just because currently spacecraft are all 'tin cans' with no life other than the astronauts and perhaps a couple of experimental plants or animals, and no room to swing a cat even if one was brought along, doesn't mean that it will always be thus.
Which then leads to the next issue.
Generation Three said:
"Why are we doing this?! If we turn around now, we can get back to Earth quicker. We're so sick of eating sausage."
A generation ship would likely need an ecosystem, rather than a mere life support system - after all, that's how spaceship Earth has managed to support life for thousands of millions of years without a service call to the maintenance department.
My gawd... hogweed eventually becomes the sustainer of human life in space. The irony.
A generation ship would have to have more in common with a remote island than with the International Space Station.
I can't imagine how many generations we'll need to create a generation ship. In the end, a generation ship's benefit is limited. I mean, other than in the Wall-E sense of things. The commitment to the mission is tenable with each following generation. And I ponder just how large a crew is needed to make it work. The redundancy for the ship equipment would also be needed for the crew, engineers, doctors, mid-level accountants, justice, sanitation engineers, people that know why that blue button keeps blinking all the damn time, botanists, biologists, physicists, chemists, computer experts, someone that can fix musical instruments, educators, and one libertarian to fuck it all up. In general, novels and shows usually have one or two people do all of that stuff, but it isn't really possible.
The minimum size of a generation ship is a function of how much of it can be made self regulating. It's clearly quite a lot larger than any current spacecraft, or even any current self contained but not self sufficient artificial environments, such as aircraft carriers; And it's demonstrably smaller than the planet Earth.

That's a pretty broad bracket.

I am not aware of any good reasons to narrow this guesstimate any further at this time.

As to why we would do it, the answer is the same as to the question of why the Polynesians went looking for more Pacific Islands to settle. Because they could.

Every human society in history has contained a small minority of misfits who wanted to risk it all to go see what's over the horizon - no matter how comfortable they were at home.

#### lpetrich

##### Contributor
I've been reading this thread, because I need the answers to complete my sci-fi epic involving an intergalactic civilization.
You may be overthinking the "problem". There is no need to spell out details of how something works in a good sci-fi story. In fact, too many details can detract from the story. Just giving the ship's drive system a name should be quite sufficient... just call it the "Swammer drive" and move on with the important part of the story, the plot and character development. Let the reader imagine how that amazing Swammer Drive works.

For example, Arthur Clarke in his "foundation" series never bothered to explain how people got around the galaxy other than using 'atomics' in their ships. Roddenberry in his "Star Trek" series never explains how a transporter, food replicator, or warp drive works, what a phaser or photon torpedo was and how they worked, etc. and it didn't detract from the story line. We only know that "dilithium crystals" were needed for 'warp drive' to work likely because it was a plot device needed for one of the stories but what the 'dilithium crystals' do and how is never explained.
That's Isaac Asimov's Foundation series.

Star Trek Writers' Guide - for TOS
1. Build your episode on an action-adventure framework. We must reach out, hold and entertaina mass audience of some 20.,000,000 people or we simply don't stay on the air.
2. Tell your story about people, not about science and gadgetry. Joe Friday doesn't stop to explain the mechanics of his .38 before he uses it; Kildare never did a monologue about the theory of anesthetics; Matt Dillon never identifies and discusses the breed of his horse before he rides off on it.
3. Keep in mind that science fiction is not a separate field of literature with rules of its own, but, indeed, needs the same ingredients as any story -- including a jeopardy of some type to someone we learn to care about, climactic build, sound motivitation, you know the list.
4. Then, with that firm foundation established, interweave in it any statement to be made about man, society and so on. Yes, we want you to have something to say, but say it entertainingly as you do on any other show. We don't need essays, however brilliant.
5. Remember always that STAR TREK is never fantasy; whatever happens, no matter how unusual or bizarre, must have some basis in either fact or theory and stay true to that premise (don't give the enemy Starflight capability and then have them engage our vessel with grappling hooks and drawn swords.)
6. Don't try to tell a story about whole civilizations. We've never yet been able to get a usable story from a writer who began... "I see the strange civilization which...".
7. Stop worrying about not being a scientist. How many cowboys, police officers and doctors wrote westerns, detective and hospital shows?
TNG-WritersDirectorsGuide.pdf For ST:TNG -- it isn't OCRed, unlike the TOS one.
BELIEVABILITY IS EVERYTHING. IT IS THE MOST ESSENTIAL ELEMENT OF ANY STAR TREK STORY.

If you're in doubt about a scene, you can apply this simple test: "Would I believe this if it was occurring today on the bridge of the battleship Missouri?" Technology aside, if you wouldn't believe the essential story happening in the Twentieth Century, then our audience probably won't believe it in the Twenty-Fourth.

#### skepticalbip

##### Contributor
I've been reading this thread, because I need the answers to complete my sci-fi epic involving an intergalactic civilization.
You may be overthinking the "problem". There is no need to spell out details of how something works in a good sci-fi story. In fact, too many details can detract from the story. Just giving the ship's drive system a name should be quite sufficient... just call it the "Swammer drive" and move on with the important part of the story, the plot and character development. Let the reader imagine how that amazing Swammer Drive works.

For example, Arthur Clarke in his "foundation" series never bothered to explain how people got around the galaxy other than using 'atomics' in their ships. Roddenberry in his "Star Trek" series never explains how a transporter, food replicator, or warp drive works, what a phaser or photon torpedo was and how they worked, etc. and it didn't detract from the story line. We only know that "dilithium crystals" were needed for 'warp drive' to work likely because it was a plot device needed for one of the stories but what the 'dilithium crystals' do and how is never explained.
That's Isaac Asimov's Foundation series.
A bit of a brain fart on my part.... My error.

#### steve_bank

##### Diabetic retinopathy and poor eyesight. Typos ...
All you have to do is put a light on the back of the ship behind a dfuuser. Turn on the light and the ship moves.

#### lpetrich

##### Contributor
Writer's Guidelines - Contact Us | Analog Science Fiction - "We publish science fiction stories in which some aspect of future science or technology is so integral to the plot that, if that aspect were removed, the story would collapse. Try to picture Mary Shelley's Frankenstein without the science and you'll see what I mean. No story!"

It Is Easy To Predict an Automobile in 1880; It Is Very Hard To Predict a Traffic Problem – Quote Investigator -- looks for which SF author first stated something like that.

Prediction or influence? Sci-fi books that predicted the future | Internet Infidels Discussion Board - a thread on SF as predictive literature.

#### lpetrich

##### Contributor
All you have to do is put a light on the back of the ship behind a dfuuser. Turn on the light and the ship moves.
Yes, but try calculating how much thrust that you'll be able to get.

Hint: it's teeny teeny teeny teeny tiny.

#### skepticalbip

##### Contributor
Writer's Guidelines - Contact Us | Analog Science Fiction - "We publish science fiction stories in which some aspect of future science or technology is so integral to the plot that, if that aspect were removed, the story would collapse. Try to picture Mary Shelley's Frankenstein without the science and you'll see what I mean. No story!"
Yes, "some aspect of future science" is what makes it science fiction. Without that, it is just fiction.

But writing science fiction does not mean that the specific details of exactly how that future science works needs to be explained. If the writer knew that then he would be a genius inventor rather than a fiction writer. Take the hard sci-fi story, "Contact", a lot of current science is in the story but only what the 'future science' does not how it works is covered. There is no attempt to try to explain how that spinning capsule transported Ellie Arroway across the galaxy, only that the 'alien science' did it.

#### Jimmy Higgins

##### Contributor
Humans have nothing like a generation ship set up on Earth
I disagree. The Austronesian people colonised the Pacific Ocean by this means and handled it just fine for three thousand years before the arrival of fast steamships and radio put a close to their isolated lifestyle.
An island isn't outer space.
There are still some small, isolated human groups with only a couple of hundred individuals.

The Sentinelese people of the Andaman Islands in the Indian Ocean are completely isolated from the rest of humanity, and some estimates put their population as low as fifty. They still retain sufficient sanity to understand that missionaries are best killed on sight.
Isolation from people isn't as much the issue as isolation from the environment itself. Living in a tin can forever, we aren't exactly wired for that. And while we can choose who starts that process, the generations afterwards might not be able to handle it as well. Granted, it would be all they know, so possibly could work.
Just because currently spacecraft are all 'tin cans' with no life other than the astronauts and perhaps a couple of experimental plants or animals, and no room to swing a cat even if one was brought along, doesn't mean that it will always be thus.
Which then leads to the next issue.
Generation Three said:
"Why are we doing this?! If we turn around now, we can get back to Earth quicker. We're so sick of eating sausage."
A generation ship would likely need an ecosystem, rather than a mere life support system - after all, that's how spaceship Earth has managed to support life for thousands of millions of years without a service call to the maintenance department.
My gawd... hogweed eventually becomes the sustainer of human life in space. The irony.
A generation ship would have to have more in common with a remote island than with the International Space Station.
I can't imagine how many generations we'll need to create a generation ship. In the end, a generation ship's benefit is limited. I mean, other than in the Wall-E sense of things. The commitment to the mission is tenable with each following generation. And I ponder just how large a crew is needed to make it work. The redundancy for the ship equipment would also be needed for the crew, engineers, doctors, mid-level accountants, justice, sanitation engineers, people that know why that blue button keeps blinking all the damn time, botanists, biologists, physicists, chemists, computer experts, someone that can fix musical instruments, educators, and one libertarian to fuck it all up. In general, novels and shows usually have one or two people do all of that stuff, but it isn't really possible.
The minimum size of a generation ship is a function of how much of it can be made self regulating. It's clearly quite a lot larger than any current spacecraft, or even any current self contained but not self sufficient artificial environments, such as aircraft carriers; And it's demonstrably smaller than the planet Earth.

That's a pretty broad bracket.

I am not aware of any good reasons to narrow this guesstimate any further at this time.

As to why we would do it, the answer is the same as to the question of why the Polynesians went looking for more Pacific Islands to settle. Because they could.

Every human society in history has contained a small minority of misfits who wanted to risk it all to go see what's over the horizon - no matter how comfortable they were at home.
Except this ship would cost tens (hundreds?) of trillions in today’s money. This isn’t just some voyagers getting on a ship and sailing away. There is zero return on this trip for any person putting money out for this.

#### bilby

##### Fair dinkum thinkum
Humans have nothing like a generation ship set up on Earth
I disagree. The Austronesian people colonised the Pacific Ocean by this means and handled it just fine for three thousand years before the arrival of fast steamships and radio put a close to their isolated lifestyle.
An island isn't outer space.
There are still some small, isolated human groups with only a couple of hundred individuals.

The Sentinelese people of the Andaman Islands in the Indian Ocean are completely isolated from the rest of humanity, and some estimates put their population as low as fifty. They still retain sufficient sanity to understand that missionaries are best killed on sight.
Isolation from people isn't as much the issue as isolation from the environment itself. Living in a tin can forever, we aren't exactly wired for that. And while we can choose who starts that process, the generations afterwards might not be able to handle it as well. Granted, it would be all they know, so possibly could work.
Just because currently spacecraft are all 'tin cans' with no life other than the astronauts and perhaps a couple of experimental plants or animals, and no room to swing a cat even if one was brought along, doesn't mean that it will always be thus.
Which then leads to the next issue.
Generation Three said:
"Why are we doing this?! If we turn around now, we can get back to Earth quicker. We're so sick of eating sausage."
A generation ship would likely need an ecosystem, rather than a mere life support system - after all, that's how spaceship Earth has managed to support life for thousands of millions of years without a service call to the maintenance department.
My gawd... hogweed eventually becomes the sustainer of human life in space. The irony.
A generation ship would have to have more in common with a remote island than with the International Space Station.
I can't imagine how many generations we'll need to create a generation ship. In the end, a generation ship's benefit is limited. I mean, other than in the Wall-E sense of things. The commitment to the mission is tenable with each following generation. And I ponder just how large a crew is needed to make it work. The redundancy for the ship equipment would also be needed for the crew, engineers, doctors, mid-level accountants, justice, sanitation engineers, people that know why that blue button keeps blinking all the damn time, botanists, biologists, physicists, chemists, computer experts, someone that can fix musical instruments, educators, and one libertarian to fuck it all up. In general, novels and shows usually have one or two people do all of that stuff, but it isn't really possible.
The minimum size of a generation ship is a function of how much of it can be made self regulating. It's clearly quite a lot larger than any current spacecraft, or even any current self contained but not self sufficient artificial environments, such as aircraft carriers; And it's demonstrably smaller than the planet Earth.

That's a pretty broad bracket.

I am not aware of any good reasons to narrow this guesstimate any further at this time.

As to why we would do it, the answer is the same as to the question of why the Polynesians went looking for more Pacific Islands to settle. Because they could.

Every human society in history has contained a small minority of misfits who wanted to risk it all to go see what's over the horizon - no matter how comfortable they were at home.
Except this ship would cost tens (hundreds?) of trillions in today’s money. This isn’t just some voyagers getting on a ship and sailing away. There is zero return on this trip for any person putting money out for this.
Why would you expect us to spend today's money?

A computer such as the phone I am writing this on would have cost trillions (and been the size of a warehouse) in 1970.

Our ancestors had basically nothing, by modern standards, even if they were hugely wealthy by the standards of their contemporaries. Henry VIII was the richest man in England, and couldn't buy soft toilet paper or a flushing lavatory.

Or descendants are unimaginably rich. They can afford it, if they want it.

#### Loren Pechtel

##### Super Moderator
Staff member
Star Trek Writers' Guide - for TOS
1. Build your episode on an action-adventure framework. We must reach out, hold and entertaina mass audience of some 20.,000,000 people or we simply don't stay on the air.
2. Tell your story about people, not about science and gadgetry. Joe Friday doesn't stop to explain the mechanics of his .38 before he uses it; Kildare never did a monologue about the theory of anesthetics; Matt Dillon never identifies and discusses the breed of his horse before he rides off on it.
3. Keep in mind that science fiction is not a separate field of literature with rules of its own, but, indeed, needs the same ingredients as any story -- including a jeopardy of some type to someone we learn to care about, climactic build, sound motivitation, you know the list.
4. Then, with that firm foundation established, interweave in it any statement to be made about man, society and so on. Yes, we want you to have something to say, but say it entertainingly as you do on any other show. We don't need essays, however brilliant.
5. Remember always that STAR TREK is never fantasy; whatever happens, no matter how unusual or bizarre, must have some basis in either fact or theory and stay true to that premise (don't give the enemy Starflight capability and then have them engage our vessel with grappling hooks and drawn swords.)
6. Don't try to tell a story about whole civilizations. We've never yet been able to get a usable story from a writer who began... "I see the strange civilization which...".
7. Stop worrying about not being a scientist. How many cowboys, police officers and doctors wrote westerns, detective and hospital shows?
TNG-WritersDirectorsGuide.pdf For ST:TNG -- it isn't OCRed, unlike the TOS one.
BELIEVABILITY IS EVERYTHING. IT IS THE MOST ESSENTIAL ELEMENT OF ANY STAR TREK STORY.

If you're in doubt about a scene, you can apply this simple test: "Would I believe this if it was occurring today on the bridge of the battleship Missouri?" Technology aside, if you wouldn't believe the essential story happening in the Twentieth Century, then our audience probably won't believe it in the Twenty-Fourth.

Star Trek is fairly soft sci-fi. There is quite a range, from stories where the technology is pretty much irrelevant to stuff like Robert L. Forward's where he's quite careful to get the numbers right and details will often be in an appendix. Or consider the Honorverse novels by David Weber--the basic tech is hand-waved but he's fairly careful with the numbers--you see plenty of math in the discussions. (There is a fundamental goof in his stories--all his math is Newtonian. At the start of the series that didn't really matter, but by now that makes the numbers substantially off.)

#### steve_bank

##### Diabetic retinopathy and poor eyesight. Typos ...
There is one more ST guideline, women in short skirts and push up pointy bras.

In an interview Roddenberry said his original vision of Capt Kirk was a red blooded American male roaming the galaxy n search of a piece of ass, his words.

Using an old term, ST had a lot of 'cheesecake'.

#### lpetrich

##### Contributor
Grading SF for Realism - Kheper -- it ranges from present-day tech to not much more than fantasy.

I remember when Lee Correy's "Shuttle Down" appeared in Analog Science Fiction. I wondered what it was doing there, since it was all present-day technology. But it was advanced present-day tech, and the story explored the implications of that tech. In the story, a Space Shuttle takes off from Vandenberg Air Force Base, and it has to land in Easter Island. This leads to a bureaucratic nightmare, because of a shortage of documents indicating ownership of the downed spaceplane.

From that grading site, from hard to soft:
• Present-day tech: Cutting edge Present Day Tech, some developments and speculation, but nothing major that has not been attained today (so no AI). Basic space exploration, very near future.
• Ultra hard (diamond hard): Plausible developments of contemporary technologies – AI, Constrained Nanotech, DNI, Interplanetary colonisation, Genetically engineered lifeforms. Nothing that conflicts with the laws of physics, chemistry, biology etc as currently understood.
• Very hard: Plausible developments of provocative contemporary ideas, bot nothing that conflicts with the known laws of physics, information theory, etc – Assembler Nanotech, Nano-Goo, Uploads, Interstellar colonisation, Relativistic ships, vacuum-adapted life.
• Plausibly hard: The above but with the addition of some very speculative themes, some of which may well turn out to be impossible, others may be possible. Requires some modification of current understanding, but nothing that is logically impossible, or has been conclusively proved to be impossible (so no FTL without time travel) – Wormholes, Reactionless Drive, Sub-nanotech (Femto-, Plank, etc), Domain Walls, exotic matter, FTL drive with time travel, etc.
• Firm: As realistic as the above categories were it not for unrealistic/impossible plot devices (e.g. FTL without time travel paradoxes), although these are kept to a minimum as much as possible.
• Medium: Similar to the above but with a larger number of unrealistic plot devices; e.g. FTL without real explanation (ore with pseudo-explanation), alien biota in some instances very similar to terragen life, psionics, a great many alien civilizations. However still preserves plot and worldbuilding consistency, and the science is good and consistent.
• Soft: A number of unscientific themes – e.g. aliens as anthropomorphic “furries”, handwavium disintegrator guns, Alien Cultures and psychology all extremely uniform, and so on. However, still retains story consistency.
• Very soft: As above but either even more unscientific elements (humanoid of the week, lifeless planets with beathable atmosphere, etc), and story with less consistency.
• Mushy soft: As above but even more unscientific (alien races never before encountered speak perfect English without a translator, animals too large to stand in Earth gravity (Godzilla), weapons that make energy beams without putting energy in, interstellar travel without FTL or centuries long voyage, mutants with super energy powers, etc).

#### lpetrich

##### Contributor
Most visual-media sf they rate as well on the soft side:
• Soft: Various TV series: Babylon 5, Farscape, Andromeda, Matrix, StarGate for the most part.
• Very soft: Various TV and movie series; for the most part the Star Trek Canon and Star Wars Canon.
• Mushy soft: Godzilla, Comic Book Superheros, badly written TV sci fi, elements of some franchises.
In their table, all of their harder-SF examples are in print media. Isaac Asimov's Foundation series they rate as firm and Frank Herbert's Dune series as medium.

But some visual-media SF has been well on the hard side. "2001: A Space Odyssey" is ultra hard except for the ET's, which are plausibly hard, and "The Martian" is also ultra hard, as far as I can tell about it. "Interstellar" is plausibly hard.

-

I must note that here is another hard-soft dimension worth mentioning: nuts and bolts / technology -- psychological / sociological

#### Swammerdami

Staff member
I've been reading this thread, because I need the answers to complete my sci-fi epic involving an intergalactic civilization.
...
With 0.01 c we should be able to travel from one end of the Milky Way to the other in just several million years. And thoroughly explore the galaxy in about twice that time, assuming it takes 1000 years or so to set up a system's power stations.
You may be overthinking the "problem". There is no need to spell out details of how something works in a good sci-fi story. In fact, too many details can detract from the story.
Real-world constraints, e.g. a 0.01c top speed, make the achievements of the inter-galactic civilization all the more grandiose and impressive.

Appeal to a mass audience is not a priority; indeed the odds are millions-to-one against on the book ever being written.

My spy thriller Plutonium in Pattaya has a slightly higher chance of completion. But my enthusiasm for that project waned as I saw some of my far-fetched plot twists effected in the real world.
There is one more ST guideline, women in short skirts and push up pointy bras.

In an interview Roddenberry said his original vision of Capt Kirk was a red blooded American male roaming the galaxy n search of a piece of ass, his words.

Using an old term, ST had a lot of 'cheesecake'.
I'm afraid that my Plutonium in Pattaya may overdo the "cheesecake" a bit.

#### Loren Pechtel

##### Super Moderator
Staff member
Most visual-media sf they rate as well on the soft side:
• Soft: Various TV series: Babylon 5, Farscape, Andromeda, Matrix, StarGate for the most part.
• Very soft: Various TV and movie series; for the most part the Star Trek Canon and Star Wars Canon.
• Mushy soft: Godzilla, Comic Book Superheros, badly written TV sci fi, elements of some franchises.
In their table, all of their harder-SF examples are in print media. Isaac Asimov's Foundation series they rate as firm and Frank Herbert's Dune series as medium.

But some visual-media SF has been well on the hard side. "2001: A Space Odyssey" is ultra hard except for the ET's, which are plausibly hard, and "The Martian" is also ultra hard, as far as I can tell about it. "Interstellar" is plausibly hard.

-

I must note that here is another hard-soft dimension worth mentioning: nuts and bolts / technology -- psychological / sociological

I wouldn't call The Martian as ultra-hard--the storm that triggered the whole thing is definitely wrong. (The author knew it when he wrote it--he needed it for the story.)

#### steve_bank

##### Diabetic retinopathy and poor eyesight. Typos ...
I was a regular reader of Analog.