I wonder if any talented people have actually thought about what might be involved in a Starship capable of anything useful like half-lightspeed?
Popular Mecahnics is a useful site on occasion:
What Would a Starship Actually Look Like?
Clearly our chemical moon rockets capable of 7 miles/second, IIRC, are useless. The speed of light is 186,000 miles per second.
I just don't know if fusion power might work. My intuition says it is hopelessly inefficient at a percent or so mass to energy yield. But shall sleep on it.
Popular Mecahnics is a useful site on occasion:
What Would a Starship Actually Look Like?
Clearly our chemical moon rockets capable of 7 miles/second, IIRC, are useless. The speed of light is 186,000 miles per second.
I just don't know if fusion power might work. My intuition says it is hopelessly inefficient at a percent or so mass to energy yield. But shall sleep on it.
Feels like I'm practically back to normal now, being a somewhat naturally asocial individual, I'm more than happy communicating with people at work and my wife and kids.
Increasingly rarer for me to actively seek out social interaction.
"Jeg trives i mitt eget skinn" - I thrive in my own skin
At any rate, was thinking that in order to get the science moving a bit faster they should start mixing the employees a bit. Get the rocket scientists, project planners and the chemists to work alongside mechanics like that guy who managed to get over 260 Naturally Aspirated HP out of a 1.6 liter Toyota 4AG more or less in a garage, and mix in some professional rally drivers, they frequently bend and break the rules of physics so it should get things moving along quite nicely methinks.
2019 Trento Bondone - Mikko Kataja - Toyota Starlet 16V 1600cc - YouTube
Increasingly rarer for me to actively seek out social interaction.
"Jeg trives i mitt eget skinn" - I thrive in my own skin
At any rate, was thinking that in order to get the science moving a bit faster they should start mixing the employees a bit. Get the rocket scientists, project planners and the chemists to work alongside mechanics like that guy who managed to get over 260 Naturally Aspirated HP out of a 1.6 liter Toyota 4AG more or less in a garage, and mix in some professional rally drivers, they frequently bend and break the rules of physics so it should get things moving along quite nicely methinks.
2019 Trento Bondone - Mikko Kataja - Toyota Starlet 16V 1600cc - YouTube
In a crisis such as the one we are living through, other people can be disappointing.
That must be why my erstwhile friends have stopped corresponding with me!
Hibernation on a starship looks like a good option for me right now!
Attachments
Randall Munroe (cartoonist known for XKCD) describes in his book "What If?" a baseball being pitched at 0.95C. Really bad things happen incredibly fast.
How hard can it be to design a starship?
We know F=MA and all that. We are off to Alpha Centauri 4 light years away.
So far I have guessed it might weigh about 5010 Metric Tonnes. 10 tonnes is payload, like that recent splendid SpaceX capsule with Doug and Bob on it.
About the size of a Type 45 destroyer overall. Let's see if it works.
Way I see it, it needs about 4X 1000 tonne boosters to get up to however fast it goes. Now for the slowing down leg, it sheds 4000 tonnes. It now weighs 1010 tonnes so ought to be able to slow down for landing. The payload is 10 tonnes of humans and life support.
Anybody want to do the maths with different efficiency types of fuel?
I have made a bit of progress:
Nuclear fusion - Wikipedia
Fusion yield is a few MeV (maybe 4) for two combining deuterons (heavy hydrogen) to make helium. The mass of helium must be about 3,700 MeV. so about 0.1% conversion.
Interestingly even at the centre of the sun, the heat production is apparently quite low. About a 1/4 of what your body makes in a given volume.
Now we just need to do the maths for a rocket. I would think if you work out how fast a 4MeV Helium nucleus is travelling, we might get a ballpark speed for the starship. This must be the sort of thing that goes on in particle colliders. So oughtn't to be hard to find out. I am thinking a 1 MeV proton must be about the same speed.
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The AEPS ion thruster seems to be the current solution?
Advanced Electric Propulsion System - Wikipedia
Kind of hard to use solar arrays to power a trip to Alpha Centauri, would need a system to generate power for the duration of the trip. And some kind of solution that can provide power for the colony for several years at least. Some sort of excavator(s), means of basic transportation, 3d printers, parts for a sintering furnace (or two), materials to expand the spacecraft to a semi-permanent sealed base, greenhouse +++
10 tonnes will not get you very far, would perhaps be a bit rude to send people there if they got a snowballs chance in hell to survive.
Would be nice if they had some time to check out options on suitable locations when they first got there, don't want to rush it when selecting a spot for first base.
Advanced Electric Propulsion System - Wikipedia
Kind of hard to use solar arrays to power a trip to Alpha Centauri, would need a system to generate power for the duration of the trip. And some kind of solution that can provide power for the colony for several years at least. Some sort of excavator(s), means of basic transportation, 3d printers, parts for a sintering furnace (or two), materials to expand the spacecraft to a semi-permanent sealed base, greenhouse +++
10 tonnes will not get you very far, would perhaps be a bit rude to send people there if they got a snowballs chance in hell to survive.
Would be nice if they had some time to check out options on suitable locations when they first got there, don't want to rush it when selecting a spot for first base.
“ Interestingly even at the centre of the sun, the heat production is apparently quite low. About a 1/4 of what your body makes in a given volume.”
Yes, very low. I heard it described as about the same as the centre of your average garden compost heap. Of Course the volume is enormous, ergo lots of energy. The rate of conversion from Hydrogen to Helium is something like 1 in 10^30 atoms - (can’t remember the exact figure) - so absolutely minute.
Yes, very low. I heard it described as about the same as the centre of your average garden compost heap. Of Course the volume is enormous, ergo lots of energy. The rate of conversion from Hydrogen to Helium is something like 1 in 10^30 atoms - (can’t remember the exact figure) - so absolutely minute.
I did the sums for Nuclear Fission.
Apparently about 0.9 MeV energy released per nucleon. Binding energy goes from 7.6 MeV to 8.5 Mev per nucleon as you move from Uranium down to smaller fission products like Iron.
Which is about the same as for fusion. So a contender.
Apparently about 0.9 MeV energy released per nucleon. Binding energy goes from 7.6 MeV to 8.5 Mev per nucleon as you move from Uranium down to smaller fission products like Iron.
Which is about the same as for fusion. So a contender.
I wonder wether humans will reach other planetary systems.
The task is humongous, OTH we have many millions of years to achieve it. So who knows, may be we will destroy ourselves, before our sun does.
Probably what happened to many ETs, that would have visited us. But at least we should be visited by robots, their outer space probes or the robot civilisation than overtook them.
The task is humongous, OTH we have many millions of years to achieve it. So who knows, may be we will destroy ourselves, before our sun does.
Probably what happened to many ETs, that would have visited us. But at least we should be visited by robots, their outer space probes or the robot civilisation than overtook them.
If I was ultimate dictator of the Solar system, and I had the means to do so:
First thing I would do is start grabbing matter from around Saturn and ram it in a controlled manner into Mars as part of a terraforming process and to increase mass and adjust spin. Then I would make a fitting moon to Mars to help recreate the basis of a more constant weather system. After the dust has settled it is time to figure out which kind of vegetation is suitable, and whether or not the influx of matter and water has triggered latent life, after an evaluation process it is time to selectively bombarb specific areas with suitable seeds.
We can do most of this using robots, no need to go there until we have done the basics IMO.
First thing I would do is start grabbing matter from around Saturn and ram it in a controlled manner into Mars as part of a terraforming process and to increase mass and adjust spin. Then I would make a fitting moon to Mars to help recreate the basis of a more constant weather system. After the dust has settled it is time to figure out which kind of vegetation is suitable, and whether or not the influx of matter and water has triggered latent life, after an evaluation process it is time to selectively bombarb specific areas with suitable seeds.
We can do most of this using robots, no need to go there until we have done the basics IMO.
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Carl Sagan - back in the day - proposed releasing bacteria into the upper atmosphere of Venus. The thinking at the time was that its then understood to be carbon dioxide atmosphere could be converted to an oxegen rich one. Problem is its also rich in sulphuric acid.
As a kid I remember reading in science books from the 50's and very early 60's about possible steaming hot jungles on Venus, After the Russians got there, that idea quickly came to an end. We now know better of course.
Problem with terraforming Mars is that it has no magnetic field so it going to get blasted with high energy particles from the sun which will strip off any atmosphere you try to build. In any event, you would need to add a lot of mass as well to retain any atmosphere.
Maybe Titan is a better bet - thick atmosphere but you'll need some winter woollies thats for sure. Jovian moons might be problematic - the planets mag field is brutal and it accelerates particles along its flux lines. I was reading somewhere they are moving at +100k kilometers per hour.
Looks like out present place of residence is about the best we can hope for.
As a kid I remember reading in science books from the 50's and very early 60's about possible steaming hot jungles on Venus, After the Russians got there, that idea quickly came to an end. We now know better of course.
Problem with terraforming Mars is that it has no magnetic field so it going to get blasted with high energy particles from the sun which will strip off any atmosphere you try to build. In any event, you would need to add a lot of mass as well to retain any atmosphere.
Maybe Titan is a better bet - thick atmosphere but you'll need some winter woollies thats for sure. Jovian moons might be problematic - the planets mag field is brutal and it accelerates particles along its flux lines. I was reading somewhere they are moving at +100k kilometers per hour.
Looks like out present place of residence is about the best we can hope for.
Yes, interstellar travel all looks a bit problematic.
My back of a beermat Physics was surprisingly good:
Relativistic Energy
1 proton mass and 1.4 x 10^7 m/s comes out to 0.046 lightspeed for 1.02 MeV yield.
Boffins reckon they might get 12% lightspeed with two stages and some tinkering. Could get somewhere in about 50 years.
Project Daedalus – Interstellar Mission
Big old lump that Daedelus when you consider the Saturn V alongside was 3,000 tonnes.
The project has been brought up to date recently with Icarus:
Project Icarus: Laying the Plans for Interstellar Travel - The Atlantic
My back of a beermat Physics was surprisingly good:
Relativistic Energy
1 proton mass and 1.4 x 10^7 m/s comes out to 0.046 lightspeed for 1.02 MeV yield.
Boffins reckon they might get 12% lightspeed with two stages and some tinkering. Could get somewhere in about 50 years.
Project Daedalus – Interstellar Mission
Big old lump that Daedelus when you consider the Saturn V alongside was 3,000 tonnes.
The project has been brought up to date recently with Icarus:
Project Icarus: Laying the Plans for Interstellar Travel - The Atlantic
Indeed, I was thinking that if you choose enough iron rich matter to bombard specific points on the surface you could get enough reaction to fire up a molten core, then go for a bit more rock to seal it off at a certain point, ice bombardment on the caps. Would take a bit of time, better get a head start. But you're right, probably a bit far fetched.
Maybe another thing would be to make a mini-sun with enough gravity for us inside a Dyson Sphere.
Experimental Advanced Superconducting Tokamak - Wikipedia
Dyson sphere - Wikipedia
Stellar engine - Wikipedia
Ew, bit slow considering the engineering effort, isn't it?
I make 20 m/s to be 45 mph. It'd be quicker to ride a horse.
Enable | Horse Profile | Sky Sports Horse Racing
Ew, bit slow considering the engineering effort, isn't it?
I make 20 m/s to be 45 mph. It'd be quicker to ride a horse.
Enable | Horse Profile | Sky Sports Horse Racing
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