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Astronomers To Announce Discovery of a Nearby 'Earth-Like' Planet (seeker.com)
astroengine quotes a report from Seeker:
Scientists are preparing to unveil a new planet in our galactic neighborhood which is "believed to be Earth-like" and orbits its star at a distance that could favor life, German weekly Der Spiegel reported Friday. The exoplanet orbits a well-investigated star called Proxima Centauri, part of the Alpha Centauri star system, the magazine said, quoting anonymous sources.
"The still nameless planet is believed to be Earth-like and orbits at a distance to Proxima Centauri that could allow it to have liquid water on its surface -- an important requirement for the emergence of life," said the magazine.
It's orbiting our sun's nearest neighboring star -- just 4.25 light years away -- meaning it could someday be considered for the world's first interstellar mission.
"The still nameless planet is believed to be Earth-like and orbits at a distance to Proxima Centauri that could allow it to have liquid water on its surface -- an important requirement for the emergence of life," said the magazine.
It's orbiting our sun's nearest neighboring star -- just 4.25 light years away -- meaning it could someday be considered for the world's first interstellar mission.
"meaning it could someday be considered for the world's first interstellar mission."
This is the longest timescale for 'someday' ever. Not going to happen in the lifetime of any descendent we can imagine.
If there was anyone on that planet, we could talk to them for sure. But no visiting is going to happen before humans cease to be creatures we recognise as the same as us.
The quotes should have been around 'Nearby' as well as 'Earth-Like'. Throw me a freckn bone.
Proxima Centauri is a flare star. Good luck with it being Earth-like.
ours or theirs?
Donald Trunp has just announced he wants to build a wall to keep out illegal aliens from the newly discovered planet. He also promised said aliens would be paying for the wall themselves.....
If you wanna get rich, you know that payback is a bitch
4.25 light years is still 24,984,158,550,305mi and we really don't have anything that can travel fast enough to get us there in less than tens of thousands of years.
Minimally we need to start seriously looking at a robotic probe.What is the time line for something that does a flyby? Can we get a probe up to 10%c or are we looking at even 1%c as too hard? 50 years is pretty cool. 500 or more years would be taking the risk that two things happen, one civilization falls enough that we forget we sent it. Or that in the next 500 years we easily build way faster probes.
Also with 50 years and we find something worth visiting, and now can think about sending people. 500 and we are back to science fiction.
Minimally, this justifies building one huge honking telescope to get a good look at this planet.
Physics disagrees.
http://www.space.com/32546-interstellar-spaceflight-stephen-hawking-project-starshot.html
starshot project and similar, preliminary designs of tiny probes less than a gram, in a swarm of hundreds to thouands accelerated to sizeable fraction (10-20%) of the speed of light seem like the only plausible way to explore other "nearby" star systems for the next century.
Isn't it safe to assume will would have mastered energy/matter conversion technology by the time we have the means for interstellar travel? Enclosed habitation with holodecks for "outdoor" recreational activities will be all we need.
Minimally, this justifies building one huge honking telescope to get a good look at this planet.
Didn't you read the article? They were able to take a pretty detailed picture already.
#DeleteChrome
using as reference the speed of the fastest man-made space object, about 25 miles/s or about 0.014% of speed of light, the 4.5 light year distance could be reached at 321.5 years, give or take some.
that is more than 10 generations even for late boomers...
Umm what?
We could have a probe there in 30 years... It's not even that expensive (less than a moon landing).
Is a NUCLEAR ROCKET.
The fastest probe we ever has built goes 0.023%. It is doubtful we will even get to 1%, ever.
If we could devise something that accelerates at g and decelerates at g, I've read probably get there in under a decade. The problem is that at high speeds, random space debris might annhilate your space craft.
I like the "to announce" part. Like, if they haven't announced it, why are you reporting on it? Maybe there's a reason they haven't actually announced it yet! Perhaps the data is tentative and admits of another explanation, which, on further review, will prove to be true. Perhaps it's simply one guy's wild-ass guess based on incomplete data.
Maybe, just maybe, there's a reason he's not making any comment? Like, they want to avoid making false statements in public and embarrassing themselves? Quite unlike certain (most?) Internet "news" sites which are perfectly happy both to make false statements and to embarrass themselves? "Who cares? Just give us those clicks!"
Anyway, this is pretty cool if confirmed, but at this point, I'm treating it with all the seriousness it deserves, which is approximately zero.
Under a decade? Try 30,000 years.
there's that whole Prime Directive thing
How the heck did you manage to beat slashdot's auto-link?
I am so relieved that all those colonization spaceships I've sent to Alpha Centauri, over many years of playing Civilization, will have somewhere to land!
Violence is the last refuge of the incompetent. Polar Scope Align for iOS
Seems to me I once read that early last century someone said words to the effect of "what's the point of airplanes? Not like they'll ever be able to fly nonstop across the Pacific or anything".
Oddly, your comment reminded me of that....
"I do not agree with what you say, but I will defend to the death your right to say it"
The fastest probe we ever has built goes 0.023%. It is doubtful we will even get to 1%, ever.
And yet decades have technology has improved since, and we've never built a probe for this purpose. Everything else has been built with planetary observation/fly-by in mind, not blazing out of the solar system for blazing's sake.
Don't disappoint your bird dog. Go to the range.
Unwanted on Earth, they left the reign of their new employer Bernie Sanders.
Unfortunately, Bernie Sander's woodburning rocket would take 32 million years to get there.
At 1g? That will get you to c in about a year (disregarding relativistic effects), so under a decade to travel just over 4 lightyears sounds like the right ballpark.
If construction was anything like programming, an incorrectly fitted lock would bring down the entire building...
About 14 years at ~1 G Acceleration and then Deceleration. This has been known for decades, and the subject of some really crappy Science Fiction:
https://en.wikipedia.org/wiki/Space_travel_using_constant_acceleration
The Math is there, what isn't there is the means of fueling, and the lack of clean restrooms on the way.
Prepare the Jupiter One!
Our Children will see Alpha Centauri in their lifetime via small probes propelled by lasers here on earth.
check it out....
http://www.scientificamerican.com/article/100-million-plan-will-send-probes-to-the-nearest-star1/
Hawking is a theoretical physicist, not an engineer.
While it may be theoretically possible to accelerate a small spacecraft to 0.2 c, there are many unsolved practical difficulties.
For example, when a spacecraft travels at 0.2 c, interstellar dust it encounters has more kinetic energy than a car moving at 100 mph.
Basically, all the Hydrogen gas it encountered would slam into it as hard radiation, destroying any electronics.
Also, good luck trying to take pictures at that speed, or even simple measurements.
You'll need to compensate for relativistic effects everywhere (time moves differently, geometry warps, frequencies shift, energies shift)...
"No, what AC was pointing out was that a mere 100 years ago, people made sweeping statements like "no one in our lifetime will ever fly". We were flying in commercial jet airliners less than 30 years later, and landing on the moon another 20 after that."
What?
100 years ago was 1916. Man first flew in a ballon in 1783.
Gliders? Otto Lilienthal was well know in the 1890s
Airplanes The Wright Brothers first flew was Dec 17, 1903. By 1916 hundreds of different aircraft had already flown including some pretty large aircraft.
"We were flying in commercial jet airliners less than 30 years later,"
The first jet commercial airliner the Comet did not enter service until 1952 which is well over 30 years later.
"The idea that there's 0 chance that any of us will see an interplanetary or interstellar mission is crazy."
I think you are right about interplanetary flight. I hope that we will see that in a life time. Manned Interstellar fight is where you are very much off. The difference in scale between going to Mars vs going to a star system is HUGE. Maybe we will see some supper shocking tech like an unexpected breakthrough in FTL flight.
But the odds are massively in favor of none of us today living to see a manned interstellar mission. Un manned we may live to see one launched but I doubt that we will see it arrive.
See my blog http://ilovecookes.blogspot.com/ for light hearted technical information.
Seems to me I once read that early last century someone said words to the effect of "what's the point of airplanes? Not like they'll ever be able to fly nonstop across the Pacific or anything".
Oddly, your comment reminded me of that....
Oddly, your comment reminded me of how much progress has halted, not to say reversed. We had SR-71. We had Concorde. We had the Space Shuttle. We had man on the moon.
OK, so you can't get to C since you have to have infinite power to accelerate infinite mass. (Ignoring relativistic effects proves stupid). Where would you get fuel to accelerate continuously? A Bussard ramjet? In interstellar space? They work great. In novels. I think you also might have forgotten deceleration. Unless you wanted to pass the planet at a significant fraction of light speed.
I can think of quite a few things that can survive a car at 100 mph. Like this dick. Especially when it is in full on throb mode having caught wind of your leaking asshole. Nothing could match that.
This planet will become Beziez and attack Earth and Arus in 2151. Then we have to deal with the false flagger nuts and
the end the occupation of Beziez movments on Earth, Arus and the colonies in 2218
Well, then. Make sure to launch it to the nearest star (excluding the sun). And have it send a post card when it arrives.
There is nothing stopping us from building a probe that goes that fast except for the expense (more weight) and some engineering (bigger/better shielding, more efficient rockets, bigger fuel production). We have the tech for it, we just don't have the political willpower to do it, I mean, who really wants to have a nuclear reactor going up in the air, something goes wrong and the US will be turned to dust and be inhabitable for 1000 years.
Custom electronics and digital signage for your business: www.evcircuits.com
Sanders wouldn't use his own rocket. He will just convince his Israeli friends to make a movie denigrating whites and use the profits to form lawyer alliances and sue the rich fathers of 12 year old kids that download Bieber mp3's.
Eventually he gets his rocket up.
Oh wait you're using a MAGICAL fuel source and engine. Well, that's called CHEATING.
Seven puppies were harmed during the making of this post.
stare into space.
1% C is too hard. The current fastest man made object is the Juno mission that made it to 25 miles per second. Considering that light speed is 186,000 miles per second, we've only ever reached 0.01% of the speed of light.
Seven puppies were harmed during the making of this post.
Diminishing returns kid. When you get older and the stars fade a little, you'll realize the bit about diminishing returns...
Seven puppies were harmed during the making of this post.
You started off with some very good points about precision in speech, and then you wrote the above sentence which is so wholly incorrect that it verges on funny. :-) Although I understood what you meant (I'm sure that most readers did), it's certainly not what you wrote.
Short version: the "laws of physics" are invented by Man and limited by our understanding, while the "laws of nature" or the underlying principles of reality are inherent to the universe around us. Your sentence confused the two things completely.
The laws of physics are in continuous flux as physicists redefine them, and they always will be. As they evolve, so will our capability to manipulate the fabric of reality around us using the physics at our disposal. Of one thing we can be certain: what we will be able to do in 50 years' time would be seen as preposterous science fiction today if we could glimpse the future.
Your total certainty about what is bollocks based only on our few-hundred year old state of physics was extremely funny. :-)
Seems to me I once read that early last century someone said words to the effect of "what's the point of airplanes? Not like they'll ever be able to fly nonstop across the Pacific or anything".
Oddly, your comment reminded me of that....
Oddly, your comment reminded me of how much progress has halted, not to say reversed. We had SR-71. We had Concorde. We had the Space Shuttle. We had man on the moon.
Progress was neither halted nor reversed. We had to take a step back and focus on efficiency, rather than just relying on brute force. All of those systems worked fine, but they were just too resource-intensive to justify their operation. We'll get back to the moon soon enough, and it will cost a tiny fraction of what the Apollo missions did. The SR-71 is just unnecessary today given better satellite coverage and better optics. The Concorde... that may never be back.
Note to ACs: I usually delete AC replies without reading them. If you want to talk to me, log in.
You're exaggerating the effect that a simple nuclear reactor would have even in a catastrophic failure by a whole lot.
"Oh my God. This is terrible. This is the end of my Presidency. I'm fucked."; ~ Donald J. Trump
"Basically, all the Hydrogen gas it encountered would slam into it as hard radiation, destroying any electronics."
Protons at 0.2C only have an energy of ~20MeV above Rest Energy. For decades, we have hardened Electronics to withstand substantially more than that; they are routinely tested at Berkeley, Davis, TAMU, Chalk River, etc up to the several hundred MeV level.
Those Electronics are zipping above your head right now, and in any event, a couple of millimeters of Aluminum will stop 20MeV Protons right in their tracks.
Are you _really_ an Engineer? That was a High School level mistaken claim.
who really wants to have a nuclear reactor going up in the air, something goes wrong and the US will be turned to dust and be inhabitable for 1000 years.
I don't claim to be a nuclear scientist, but I'm pretty sure that even in the worst-case scenario that would not happen.
I don't care if it's 90,000 hectares. That lake was not my doing.
More like progress has gone sideways. The focus has changed from high speed vehicles to high fuel efficiency vehicles ever since the 1970s oil crisis. It's the same reason you do not see cars powered by Wankel engines or turbines. It's not that we do not have the technology it just does not make economic sense.
Today we have satellite reconnaissance and regardless of how fast you make a jet aircraft a SAM rocket will prove to be faster. You might as well send a high-altitude relatively slow drone like the Global Hawk to make the reconnaissance.
Things might change though. There has been more emphasis on scramjet research in the last decade and the proposals for the next fighter aircraft after the F-22 have sometimes included variable cycle engines.
I saw that movie.
Oliver's law of assumed responsibility: If you're seen fixing it, you will be blamed for breaking it.
The still nameless planet is believed to be Earth-like and orbits at a distance to Proxima Centauri that could allow it to have liquid water on its surface -- an important requirement for the emergence of life," said the magazine.
Of course it's still nameless stupid. We haven't got there yet to ask the locals what the planet's called.
just 4.25 light years away - there's your problem right there.
...could happen, after all? I await the arrival of Colonel Green.
Beard? Says who? I think that has more to do with Michelangelo (and more recently, Monte Python).
BTW, have you never heard of the barber paradox? The barber who shaves every man who doesn't shave himself. Got is quite able to be that barber, whether He shaves himself or not.
PET stand for "Positron Emission Tomography". A "Positron" is identical to an electron but it has a positive charge. It is anti-matter. Want to see anti-matter in use every day? Go get your head scanned.
If you can accelerate, you can decelerate with the same technology. That assumes of course fuel. And I did say *if*.
I don't think the issue with reviving the Saturn V is the fuel, it's the cost of building those engines, and everything else that goes with it. (Including more reliable sources of electricity than Apollo 13 carried, although I guess that's solved.)
to bring you an announcement: the Jesuits will be there first.
Ok, so it's science fiction; The Sparrow (and its sequel, Children of God). But it's good sci-fi.
Not even. We are still working on SCRAMJET/RAMJET aircraft as you just mentioned. And thats just things we know of like the X-51, it doesnt even account for all the black projects the Air Force has cooking.
How the heck did you manage to beat slashdot's auto-link?
He had his post sent via antimatter rocket.
"Minimally, this justifies building one huge honking telescope to get a good look at this planet." Siriously.
The exoplanet in question, Kepler 425b is not in orbit of Proxima Centauri, at 4.25 light years distant, but rather Kepler 425 at a distance of approximately 1,400 light years. Thus, Kepler 425b is 329 times more distant than Proxima Centauri, give or take a light year or two. The New Horizons probe, which just recently flew past Pluto at a speed of 59,000 kph relative to the sun, would require 26+ million years to arrive there, assuming that it was headed in the right direction (which it's not).
Astronomers To Announce Discovery of a Nearby 'Earth-Like' Planet
Would've been nice to have some warning of this pre-announcement. Cuh.
systemd is Roko's Basilisk.
The chances of maintaining adequate containment, much less producing enough antimatter to be viable, is about the same as my ability to maintain gastrointestinal containment after eating four Taco Bell chicken tacos with fire sauce and drinking two liters of beer.
We've lost Maverick and Goose. I repeat, we've lost Maverick and Goose. All pilots pop Imodium immediately and scramble!
Cant wait to freedomize it!
I was responding to the (strange) claim that it would take 30.000 years to reach a nearby star even with an engine providing a constant 1g acceleration. Where we get that acceleration is left as an exercise to the reader.
If construction was anything like programming, an incorrectly fitted lock would bring down the entire building...
Are you _really_ an Engineer? That was a High School level mistaken claim.
Actually, I am. Are you?
If you think your piece of aluminium will still work as a shield after being constantly bombarded with protons and alpha particles for 100 years or so, you are in for a surprise.
Hint: if it works as a radiation shield, it will capture protons, and will become highly radioactive.
Not to mention that a mere 100 microgram speck of dust will go through it like a bullet.
Or at least pointing all the current radio and optical telescopes at it.
And watching it for 8 years. If it's merrily broadcasting crap out into the universe... and listening to ours... and suddenly goes "oh shit. We've been rumbled. Shut it down. Pretend we're not home."
If a Soviet-era nuclear satellite can fall to earth and not leave Canada any more radioactive and uninhabitable than it already was, then I suspect a spacecraft designed and built using modern technologies and techniques isn't going to cause much harm to anything other than whatever it happens to fall on.
Much like Intel's tick-tock approach on a larger scale. That didn't slow down CPU progress much.
Fastest man made object is believed to be a lowly manhole cover at the top of a nuclear test. Unofficially, it was calculated to be traveling at 45 miles per second.
That means we've gone to over .024% the speed of light. We just need to detonate a focused nuclear bomb under the probe with a manhole cover as a blast shield, plus another 17500+ years to coast to Proxima Centauri.
Whoosh, that's the sound sarcasm makes as it passes you by
Custom electronics and digital signage for your business: www.evcircuits.com
There is a project that would involve accelerating tiny probes to a fraction (0.2c) of the speed of light, allowing a mission to a nearby solar system. Also, that system is moving towards us at about 21km/s so the longer we wait, the shorter the trip gets (but not by much, heh).
"I have never let my schooling interfere with my education." - Mark Twain
We have accelerated particles to almost the speed of light in particle accelerators. The point being that we have to think about how small we can make a probe, and how can we accelerate that tiny device (likely light sails and lasers from Earth).
"I have never let my schooling interfere with my education." - Mark Twain
Clearly when our probes get there the only signs of life we will find will be a Melnorme trader.
we should make this probe capable of self-repair using available materials.
in fact, it should also be able to create other probes once it reaches its destination.
and every good project needs a good codename.
I suggest...Project Berserker.
The guy who said the election was rigged won the presidency with the second-most votes.
Not even. We are still working on SCRAMJET/RAMJET aircraft as you just mentioned.
Given that the first ramjet flew in 1939, and the first scramjet in 1991 (both by SU/RU), I'm not terribly impressed with our speed of progress...
Solar sails can get to 20% of c, supposedly.
It's name is Rann.
Paging Adam Strange, Adam Strange, zeta beam for you from Rann....
mark
As I said in my last answer to you: you should read more.
E.g.: http://www.electric-sailing.co...
Or: https://en.wiki2.org/wiki/Inte...
Cost free eBook I read (by iBook/Kobo/Amazon/ObookO/Gutenberg etc.): "The Green Odyssey" by Philip Jose Farmer.
Just to be clear, the proposed cost of this "get to Alpha Centauri in 20 years" project is $100M for a "nanocraft" that moves at 0.2C. To put this number in comparison, it is approximately 2.3% of the cost of the Large Hadron Collider, which we built. It is not inconceivable that, within 50 years, we could place real, live, people on this planet. That said, it would require a re-prioritization.
Just as long as we don't send the new Jupiter 2 on a course to Proxima Centauri through an meteor storm, they should arrive safely...
https://youtu.be/qhdyTwVl4RM?t=1313
No man's sky. there, this thread is now complete.
Yep, it could be them, or maybe Vulcans, Romulans, Gorn, Tholiens, etc.
You left out the part about doing this repeatedly.
The cool part about Orion propulsion was that it seemed quite plausible to scale it up to ships the size of a city block or more, and get those giant ships to Alpha Centauri in less than a century. They'd just make kind of a mess in the atmosphere on their way up.
I hereby declare war on said planet. These bastards have had it too easy for too long.
They forgot to announce they were going to announce the announcement, throw away all the data and start over.
and we really don't have anything that can travel fast enough to get us there in less than tens of thousands of years.
Actually we really do. Stop spreading misinformation. We have had nuclear power since the 1940s. A lot of you people seemed to have forgotten this amazing 20th century invention and want to pretend that chemical rockets or ultra-weak ion propulsion are the only options based on current tech. They are not.
Quite an experience to live in fear, isn't it? That's what it is to be a slave.
They'd just make kind of a mess in the atmosphere on their way up.
Which means you basically have to build them off planet. At a Lagrange point or on the moon or whatever. Yes it would probably add hundreds of years to the project to do that, but the alternative may be to never build an interstellar ship.
Quite an experience to live in fear, isn't it? That's what it is to be a slave.
I think the implication was that foreign powers would interpret it as a nuclear weapon and launch a retaliatory strike and glass the US.
One of the points of Orion was that it provided more than enough power to lift heavy vehicles from Earth's surface. (This is the hardest part for much space travel, though certainly not for interstellar travel.) If you're motivated enough -- say, if you realize that your planet is about to be rendered uninhabitable by a major asteroid strike or a previously-unsuspected large-scale variation in the Sun's output -- it'll get more off the planet quicker than anything else we've thought of.
That's exactly the point cheesybagel was trying to make. His definition of efficiency is a lot broader than yours, though.
Clean restrooms are not the problem. We can't leave till out craft has been stocked with lemon scented napkins.
James P. Hogan's comments from: https://web.archive.org/web/20...
=====
An Earth set well into the next century is going through one of its periodical crises politically, and it looks as if this time they might really press the button for the Big One. If it happens, the only chance for our species to survive would be by preserving a sliver of itself elsewhere, which in practical terms means another star, since nothing closer is readily habitable. There isn't time to organize a manned expedition of such scope from scratch. However, a robot exploratory vessel is under construction to make the first crossing to the Centauri system, and it with a crash program it would be possible to modify the designs to carry sets of human genetic data coded electronically. Additionally, a complement of incubator/nanny/tutor robots can be included, able to convert the electronic data back into chemistry and raise/educate the ensuing offspring while others prepare surface habitats and supporting infrastructure, when a habitable world is discovered. By the time we meet the "Chironians," their culture is into its fifth generation.
In the meantime, Earth went through a dodgy period, but managed in the end to muddle through. The fun begins when a generation ship housing a population of thousands arrives to "reclaim" the colony on behalf of the repressive, authoritarian regime that emerged following the crisis period. The Mayflower II brings with it all the tried and tested apparatus for bringing a recalcitrant population to heel: authority, with its power structure and symbolism, to impress; commercial institutions with the promise of wealth and possessions, to tempt and ensnare; a religious presence, to awe and instill duty and obedience; and if all else fails, armed military force to compel. But what happens when these methods encounter a population that has never been conditioned to respond?
The book has an interesting corollary. Around about the mid eighties, I received a letter notifying me that the story had been serialized in an underground Polish s.f. magazine. They hadn't exactly "stolen" it, the publishers explained, but had credited zlotys to an account in my name there, so if I ever decided to take a holiday in Poland the expenses would be covered (there was no exchange mechanism with Western currencies at that time). Then the story started surfacing in other countries of Eastern Europe, by all accounts to an enthusiastic reception. What they liked there, apparently, was the updated "Ghandiesque" formula on how bring down an oppressive regime when it's got all the guns. And a couple of years later, they were all doing it!
So I claim the credit. Forget all the tales you hear about the contradictions of Marxist economics, truth getting past the Iron Curtain via satellites and the Internet, Reagan's Star Wars program, and so on.
In 1989, after communist rule and the Wall came tumbling down, the annual European s.f. convention was held at Krakow in southern Poland, and I was invited as one of the Western guests. On the way home, I spent a few days in Warsaw and at last was able to meet the people who had published that original magazine. "Well, fine," I told them. "Finally, I can draw out all that money that you stashed away for me back in '85. One of the remarked-too hastily--that "It was worth something when we put it in the bank." (There had been two years of ruinous inflation following the outgoing regime's policy of sabotaging everything in order to be able to prove that the new ideas wouldn't work.) I said, resignedly, "Okay. How much are we talking about?" The one with a calculator tapped away for a few seconds, looked embarrassed, and announced, "Eight dollars and forty-three cents." So after the U.S. had spent trillions on its B-52s, Trident submarines, NSA, CIA, and the rest--all of it.
A 21st century issue: the irony of technologies of abundance in the hands of those still thinking in terms of scarcity.
"Actually, I am. Are you?"
Yup. One of my titles was Radiation Safety Engineer- I also ran a small Nuclear Facility, and brought in donuts for the morning crew; that is if I hadn't spent the whole night there already.
"If you think your piece of aluminium will still work as a shield after being constantly bombarded with protons and alpha particles for 100 years or so, you are in for a surprise. Hint: if it works as a radiation shield, it will capture protons, and will become highly radioactive."
At 0.2C we are talking about a few years, not a Century; you made another fundamental math mistake. Now as for the rest, you really should study some basic Radiation Physics. ~20MeV Protons come to a complete stop in Aluminum in less than 2mm, shedding Photons along the way; most of them near the end of the path at a point called the Bragg Peak. Those Electrons of the Nuclei that the Proton encounters spin or split off, yielding soft X-Rays until they are calmly captured internally again. Neither of these are long term and leave _no_ lasting Radioactivity. Now as for Nuclear Reactions; those happen very rarely due to the extremely low cross section, but 27Al + P=> 28Si... which is stable. At these energies, Spallation is possible but not probable, and again, the fragment half-lives are very short.
We used Aluminum for most of our support structures simply because even under intense bombardment, many many orders of magnitude above what would be seen in deep space, and it simply didn't get hot enough to bother much with.
Alphas, which you didn't mention initially, are more of a problem, but orders of magnitude less common than the Protons out there.
You simply have _no_ idea what you are talking about.
"Not to mention that a mere 100 microgram speck of dust will go through it like a bullet."
Specks of dust that size are mountains compared to what is currently theorized to exist in deep space. Most of the "dust" is Molecule size out there; even at 0.2C, impact energy is measured in milli-Joules, and there may only be one "Dust Molecule" for every one million cubic Kilometers, if that. Deep Space isn't like our crowded neighborhood.
What you missed out on is this:
Static Charge. The guts are Faraday Shielded, but the entire vessel could accumulate a _huge_ Static Charge compared to anything else it encounters, which could be troublesome in trying to maintain a course. Scare yourself with that one.
I doubt if you are hanging around, but really, you should do a bit of research, and work out the Math like I did, a long time ago, when I was first studying Dynamics and Kinematics. (Yeah, I'm old, but I had some assistance with my studies from two gentlemen that went by Huggins and Oppenheimer respectively. (No, not _that_ Oppenheimer, but his younger brother.))
To help with the math, remember that E=M(C^2) isn't just some handwaving on a chalkboard; E stands for "Ergs", M refers to "Grams", and that it is a dynamic equation for a Relativistic Universe, useful for producing some real numbers. "Ergs" aren't used much any longer, but since an Erg= 10(e^-7) Joules, more recent useful real numbers can be derived; quite a lot of it actually.
And you consider this to be a benefit, or a problem? From this side of the Atlantic, I see it as a useful spin-off.
Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
... not one of which turned a profit, even after a decade.
QED.
Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
cheesybagel said "The focus has changed from high speed vehicles to high _fuel_ efficiency vehicles" (emphasis added).
One of the points of Orion was that it provided more than enough power to lift heavy vehicles from Earth's surface.
I never considered that to be one of its primary advantages. It's just too dirty. Not sustainable for multiple launches. It's primary advantage is that it can carry enough fuel with it to actually go somewhere interesting in a reasonable time period. Most propulsion systems cannot. We could just just set up a spacecraft manufacturing facility on the moon and launch from there.
Quite an experience to live in fear, isn't it? That's what it is to be a slave.
Sure, given time, you wouldn't dream of launching from the ground, probably not even from the atmosphere or exosphere (pulse! pulse! pulse!). It seems to me, though, that setting up a "spacecraft manufacturing facility" (including materials production, fabrication and assembly) on the Moon is a project of many decades. Again, something you can launch this century would trump something you can't launch until next century, if you know that there isn't going to be a next century for Earth.
From a slightly different perspective, I'd happily put up with a large-scale Orion ground launch, yes, even in my back yard, to lift the equipment needed to divert a 10km dinosaur-killer asteroid. It would make a mess, but not as much of a mess as a hundred-teraton impact dumping a few thousand km^3 of rock vapor into the atmosphere.
At the same time, inflation will have increased prices to the point where we are essentially paying the exact same as we did when the first Apollo missions were launched. So, is all this pickiness over "resource-intensiveness" really worth it??? I don't see how. It just seems to be slowing us down. In the same way, people conserving energy does not really help the planet in the long run. We would have had flying cars 10 years ago if it were not for all of the worry about "energy efficiency". Seems to me that "energy efficiency" is just an excuse to allow other countries to catch up to the progress the United States made in the 20th century. I don't see any way in which me using less energy is "helping" the world. Similarly, spending less does not mean you are "saving". It just means you have slowed progress. You have to spend money to make money. This applies at all levels. You have to invest to reap the rewards of that investment. Mulling for 20 years over which investment to pick is not making a better investment.
It seems to me, though, that setting up a "spacecraft manufacturing facility" (including materials production, fabrication and assembly) on the Moon is a project of many decades.
Yes of course. I'd assume at least a 100-150 year minimum to properly set up such a facility complete with lunar mining, lunar nuclear reactors, probably earth moving equipment manufacturing, smelting and casting and machining. There is so much that would be either necessary or desirable that will take a long long time to get going.
As far as asteroids go I don't think an Orion ship would be able to change the course of any even moderately sized one. Or were you thinking as a means of getting some humans off planet to prevent the extinction of our species? In any case a pulsed nuclear ship big enough to do either of those missions would be prohibitively expensive.
Quite an experience to live in fear, isn't it? That's what it is to be a slave.
I'm thinking any plant capable of changing the course of a dinosaur-killer, at least in a timeframe of decades rather than millennia, would need an Orion to get it off the ground and deliver it to the asteroid. I'd imagine planting some sort of industrial complex, ready to crank out many square kilometers of solar panels and an array of ion drives or magnetic accelerators to spit out asteroidal metal as reaction mass. I'm not sure you're right that the Orion ship itself couldn't do the job, but I can't be bothered to run the numbers, as I'm not currently facing an actual threat of planetary annihilation.
And as for "prohibitively expensive", I agree -- except that priorities change when the alternative is certain extinction.
On a related note, while I was snooping around about Orion, I reread some info about the NERVA program. I hadn't fully realized how close that came to being deployed. It's depressing that politics cost us a reliable and affordable drive that could've taken humans to Mars and beyond. Of course, I suppose there are many who are relieved that we dodged a sky full of high-power nuclear reactors. Making compromises that disappoint people is kind of the purpose of politics.
The closest one is still on the other side of the Sun. Don't these people ever read?