Slashdot Mirror
Ask Slashdot: How Could We Actually Detect an Alien Invasion From Outer Space?
First time accepted submitter defiant.challenged writes As I was watching another sci-fi blockbuster about aliens wanting to harvest the life stock population on earth for their energy since we are such a robust species, I was wondering how likely and easy/difficult it would be currently to actually detect an outer space invasion (fleet). I am a firm believer that if we would be invaded, we would not stand a chance and would probably not even hit a single ship when it comes to fighting them. The aliens in the movie had the capability to space-jump right into our solar system and even very close to earth. My question is how good are we at the moment in detecting an alien ship/fleet that jumps into our solar system. Do we have radio dishes around the globe such that we can detect objects in space in all longitude and latitude degrees? I know we have dishes pointing to the skies but how far can they reach? Do we have blindspots perhaps on the poles? I also wonder if our current means, ie radio signals, are relatively easy to be compromised with our current stealth technology? To formulate it in more sci-fi terms, how large is our outer space detection grid, and what kind of time window can they give us?
Email Elon, see what he thinks.
Any race advanced enough to travel here to invade will have capabilities way beyond anything we could hope to combat or detect. I would imagine the first sign you would have would be if you were one of the lucky ones to see half the world wiped out a few seconds before you yourself were removed from this mortal realm.
Do you expect any other answer than "we would be fucked"?
Your detection window is probably close to 0. Any sufficiently advanced belligerant civilization capable of what you mention will probably use a relativistic kinetic weapon to wipe out Earth rather than going through all the trouble of an invasion. And why would they? IT's not that the Earth has some unique resource nonexistant anywhere else in the Universe.... So they're much safer just exterminating us.
When it is completely unclear what to expect, no predictions can be made. Hence the question is utterly stupid.
Most ACs are not even worth the keystrokes to insult them. Be generically insulted by this and ignored otherwise.
Or, maybe we should try to detect it from earth?
Frankly, any aliens able to travel here from another world are so far ahead of us, it wouldn't make any difference if we detected them or not.
However, you asked the question... so...
Our space detection system is largely aimed at Earth. For example, to warn of us of ICBM launches the first system put into space was called MIDAS between 1960 and 1966.
http://en.wikipedia.org/wiki/M...
The GPS satellites have nuclear detonation detectors, which doesn't do any good, but it another example of how our systems are aimed at Earth.
All the stuff pointed out into space, like the Hubble Space Telescope, are designed to see VERY far away and aren't looking for ships. Given the small likely size of any ships compared to planets and moons, we aren't likely to be able to see them even if we're looking for them, until they are on top of us.
After all, we still don't have a telescope that can see the moon landing sights. Pictures taken from sats in lunar orbit have gotten some pictures, but they aren't as good as you'd expect.
http://en.wikipedia.org/wiki/T...
This is the best image I could find of Apollo 11's landing site, and this was after the LRO was moved into a lower orbit:
http://featured-sites.lroc.asu...
Yea, you can tell what it is, because you know what you're looking at, but if you didn't even know where to look? You could stare at the moon for a month with such a camera and see nothing.
--
TL;DR - We likely would have no notice whatsoever of aliens until they entered orbit of Earth, and even then, it is just as likely to be a random person with a telescope who spots them as anyone from the government.
Unless of course they can be seen with the naked eye, if their ships are big enough and they are in low orbit, that is possible.
you could probably notice it after they "jumped" in.
depending on how close anyhow, how big, how much radiation/light they were emitting and all that jazz.
not that you could do shit about them if they were prepared though of course. but if they thought humans were good livestock and worth the effort of harvesting AND were capable of interstellar jumpmagic technology, you would have to ask just how fcking shitty farmers are they?
world was created 5 seconds before this post as it is.
Just a few years ago I would have implicated Sony, but Samsung's recent moves tell us that it is they who will violate confidentially.
Time is what keeps everything from happening all at once.
We probably can't detect them, but TV has taught us that the alien species are always allergic to something on earth, be it sunlight, water or a common cold.
I'm sure we'll be fine :)
I recommend that you wear your sunglasses at all times, even indoors. They are already here.
There might be some VLF/ELF deep detection that may go part way to the moon, or just beyond. So, that will pretty much be the outer limit. The entire Earth is covered from LEO 24/7, no gaps. MEO and HEO also have ballistic radars, but I suspect they do the minimum until SHTF to save power. So, assuming they reflect RF, or alter it in some detectable way (phase, amplitude, frequency, polarisation) and they are travelling around Mach 100, we may have just over 4 hours warning.
> How Soon and Far Could We Detect an Alien Invasion From Outer Space?
Nightwings is a Hugo Award winning science fiction novella by Robert Silverberg, which deals with this very topic.
I thought Iain M Banks had a rather cute description of an alien fleet arriving in Consider Phleabas
1. the first "ships" arriving at high speed go straight past and drop drones to scan and gather intelligence. If we're smart enough we might detect that. Although, reasonably large asteroids zip past us all the time and we only notice them at the last minute. if you were a war faring civilisation then using asteroids or dressing up your "ships" to look like asteroids would probably be a good move.
2. Once intelligence has been received and analysed, the main "fleet" then power up to decelerate, from an Earth position would look like lots of blue "stars" of light in the night sky getting gradually brighter for a few days/weeks/months (delete as applicable).
3. err
4. alien profit
If they have the technology to get here, then they have the technology to approach such that celestial bodies obscure them. Also, if they have the technology then be glad that they're invading when they should simply destroy the entire solar system instead. Hope they see fit to let our species survive. It's that simple.
------
The usual example given to illustrate an Outside Context Problem was imagining you were a tribe on a largish, fertile island; you'd tamed the land, invented the wheel or writing or whatever, the neighbors were cooperative or enslaved but at any rate peaceful and you were busy raising temples to yourself with all the excess productive capacity you had, you were in a position of near-absolute power and control which your hallowed ancestors could hardly have dreamed of and the whole situation was just running along nicely like a canoe on wet grass... when suddenly this bristling lump of iron appears sailless and trailing steam in the bay and these guys carrying long funny-looking sticks come ashore and announce you've just been discovered, you're all subjects of the Emperor now, he's keen on presents called tax and these bright-eyed holy men would like a word with your priests.
Banks goes on to note that most civilisations tend to encounter an Outside Context Problem only once, at the point where that particular civilisation ends or is subsumed into the more powerful one. (Incidentally this is also the title of a series of eBooks by Christopher Nuttall which are satisfyingly geeky.)
Of course, there are plenty of fictional examples of invasion, I guess ranging from the barely-competent aliens in Niven & Pournelle's "Footfall" (who were easily detected) and the almost-Gods of Arthur C Clarke's "Childhood's End" who basically just turned up without warning. It's too varied a field to come up with an idea of how we could detect them.
Never email donotemail@WeAreSpammers.com
http://xkcd.com/1377/
...but I had to sign an NDA.
I once had two ducks. I wondered what I looked like to my ducks. I decided that I look like a duck. All the extra powers that make me more than a duck - speech, thinking, telphones, etc. - are beyond the duck's imagination. To a duck, I look like a duck.
Then I wondered what an alian would look like to me, a human. I decided that an alien would look just like another human. So I began to wonder what advanced characteristics I couild watch out for. Successful businessman, good luck, healthy long life, mysterious origin, that sort of thing.
I found one. At the time he was my boss. He pretends to be Chinese, but hey, what westerner really knows what Chinese people look like?
They have landed already; and they are friendly. I was friendly to my ducks, and that Chinese family is friendly to me.
Heh, you're assuming they'd attack in space ships as if they'd escaped from some 1950s B-Movie. If they've travelled this far to 'attack' us (Whatever that might mean in this context) their technology would be so far in advance of our own we wouldn't even know we were being threatened. Hell. We might have fought and lost that battle already and you'd never know.
I had a dream, bright and carefree, but now there's doubt and gravity
Sorry, but this question is fully based on speculation. How can one even expect an serious answer on this one?
Point is: to ask the question, you need to speculate on what an alien invasion would be. You even need to speculate further to provide an answer. What's that worth? What do you learn out of it? How do I know if I can detect and observe something if I have no Idea what it is?
I could tell you, for example, that we will definitely be able to see the aliens come because of the huge gamma flash their flying saucers produce when they drop from hyperspace nearby Saturn. Our detection change is 100%. Or is it? My answer here is worth nothing, because I have to speculate to what an alien invasion would be. I could sit down with scientist, military analysis et politicians for week and make nice action plans based on what-ifs, but it would all be a waste. Why? Because we simply don't know anything about this topic.
A more serious question would be the same, but replacing "alien invasion" by "potentially hazardous asterioids". Now you can start an interesting discussion because you know what asteroids are and which one can be classified as hazardous. You know what you can observe and what you can't. Knowing the detection limits and methods, you can start to discuss about blind spot and detection probability. Going further you can even talk about mitigation, worst case scenarios and post-impact solutions. On this one I'd gladly sit down with other experts.
Beta?
Well, an invasion would not normally happen out of the blue. It would normally be preceded by scouting parties, etc, to determine the strength and/or weaknesses of the adversary. So I guess the first step in detecting a possible invasion would be to detect the scouting party. Anyway, according to Fermi's Paradox, I think we should have been invaded long ago, that is, if there are any aliens out there to invade.
What you should be concerning yourself with, human, is how to detect a comet made of translucent ice 3D printed into the shape of a meta material cloak.
Why waste all that energy to get there, when we can take our time by resetting the complexity clock every few million years?
Has the benefit of plausible deniability, just in case the monkeys are tougher than expected.
We aren't good enough to spot those yet either ....
Easy they would have Kaspersky, and the rest of the antivirus industry trying to convince them that they need to buy their products or else their spaceships, will become infected and there homes will burn down and they will get their arseholes raped by a AIDS, infected black man with mycobacterium ulcerans flesh eating disease. Just saying..
https://www.youtube.com/watch?v=FGexJ2l8LOM
We actually have quite many detectors pointing in every direction and these are for detecting different kinds of interesting stuff. Gamma rays, radio, gravity waves, neutrinos, asteroids, and so forth. There are satellites and ground based detectors to make sure that there is essentially no blind spot, not even behind the Moon or the Sun, and the detectors are very very sensitive. These are all automatic and will report anomalies quite fast. Most of these are even linked to other detectors that would try to capture events in another medium. For instance, when we detect a gamma day burst, we want to detect it in optical and gravity as soon as possible. We also have an army of amateur astronomers with very good telescopes (with wide fields of view) trying to hunt asteroids, comets, and by all means.. aliens too (we've found none yet, in case you were wondering). So, in an event of an alien fleet would suddenly appear in our solar system, I'd guess that such an agent would register as an anomaly in all kinds of different detectors, and turn pretty much the world's eyes towards it within hours. Astronomers are very keen of detecting new and strange phenomena. I think the alien technology would be pretty advanced to cloak it from detection in such different mediums as broad spectrum electro magnetic (gamma, optical and radio), neutrino and gravity. I think such technology would have to be so utterly alien that we probably would detect an innovation, even in progress.. we might already be invaded and exploited. And what would be the point of fending off such innovation, if we wouldn't even take notice of it?
- Henrik
- when the Shadows descend -
http://neo.jpl.nasa.gov/neo.html/
This is not the sig you're looking for.
Assuming they don't use some sort of anti radar/optical material/scifi cloaking... they should be detectable if we have a full radar/optical map of the whole solar system. This is more a problem of computation then anything. You get a series of cameras and radar receivers and they all take regular scans of the whole solar system. Anything "ship" sized should be logged and fed into a model of the solar system. Anything that deviates from one scan to the next was either influenced by something the model did not account for or is operating under its own power.
I've decided to stop wasting my time responding to AC trolls/sockpuppets... so if you want a response from me... login.
As other poster pointed out : no because our detection system are mostly directed toward earth, and the few toward space cover not even a single % of sky at any time. But the reason why it is so is trivially simple : the energy requirement, and the distance make it an extremely improbable event, and why would we spend money for that ?
C. Sagan : A demon haunted world:
http://www.amazon.com/gp/product/0345409469/
visit randi.org
To me the best argument against an invasion is this (not mine, of course): with all the incredible technology they would have, they would find what they need in millions best places in the galaxy. Why should they chose one little planet among billions ones, and just the rare one that's hosting life? Unless they are sadist and enjoy killing living beings, of course, but that would be a too much expensive hobby even for them, I guess...
We have problems spotting and tracking 1km-long rocks in space beyond the Earth's orbit. We literally get taken by surprise by large rocks and their orbits all the time, whizzing around our solar system without us knowing they're there.
We're also not looking for those kinds of things, as such. A ship of some description able to sense us from afar and come into the system probably wouldn't jump in at the third planet out by default. They'd probably jump in off-axis, far away, and we'd be hard pushed to spot anything of space ship size (http://io9.com/nasa-spots-a-po...
That wasn't spotted for ages, discovered only in 2013, when it was only 10 times the moon's distance away (nearly a Mars distance). It was spotted only by something looking for near-earth objects and only because it looked like its natural trajectory may bring it close to Earth in the next 100 or so years. It's 650 metres long, orbits every three years and could weigh tens or hundreds of thousands of tons.
We can't see this kind of stuff. The angles and chances are just too small and anything that settles into a natural orbit is basically indistinguishable from a rock. It wouldn't take much for something to jump in just outside the outer planets and settle, say, a Saturn distance away, probably off-axis (hiding in-axis may well give shadows etc. that give it away and we likely look at the planets and other things in our axis more than elsewhere) and we'd never spot it. Never. If we did, we'd think it was a rock.
From there, a basic telescope (or a pair of binoculars) would be able to light us up like a Christmas tree, show us to be particularly interesting, and a simple radio antenna would be able to prove that their was life on here, while at the same time being basically invisible to us without even trying.
Any civilisation with a 1km intra-system space-ship capability likely has much better tech than a $200 telescope and a satellite dish connected to a radio scanner, They'd know we were here, and be able to observe us for centuries, long before we ever would know they were there - and we'd probably NOT know they were anything other than a rock.
The distances are too immense, the angles involved far too tiny once you get out past the moon, and there's just too much stuff moving about if you have a sensitive instrument. Hell, we don't even reliably know what everything in EARTH ORBIT is, let alone trying to go out to even a Moon-distance or Mars-distance or Neptune-distance.
Basically, we would never know. The only way to get to the point we would know would be to colonise enough of the solar systems to provide mapping and triangulation of the entire space in-between, And even then, you probably could still hide if you were at all careful.
How did the American Indians detect the Europeans?
I suggest we *not* do that...
Also how did the Poles detect the Mongols?
Let's *not* do that, either...
just write a virus on your apple powerbook and upload it to their mothership
problem solved
neil degrasse tyson understands:
http://www.goodreads.com/quote...
We conquer the Independence Day aliens by having a Macintosh laptop computer upload a software virus to the mothership (which happens to be one-fifth the mass of the Moon), thus disarming its protective force field. I don’t know about you, but back in 1996 I had trouble just uploading files to other computers within my own department, especially when the operating systems were different. There is only one solution: the entire defense system for the alien mothership must have been powered by the same release of Apple Computer’s system software as the laptop computer that delivered the virus.
duh! easy as pie
intellectual property law is philosophically incoherent. it is your moral duty to ignore it or sabotage it
They will come here slower or faster than the speed of light? If they come faster, no matter what technology we have to detect them, they will be here before the light of their travel. And if they are using something like the alcubierre drive, life on the entire solar system may be wiped on arrival anyway, with no defense possible.
And if they are coming slower than the speed of light, taking decades or centuries of their timeframe, they probably won't be an invasion or destruction force. Is just too much investment of time and resources for what you may get cheaper elsewhere. What makes us unique is our culture, and that would not survive an invasion.
When meteorites fall, they're typically unexpected until they enter the atmosphere. Unless the alien fleet announced its presence by radio on a frequency we're listening to, we probably wouldn't know they were here until they were in the atmosphere. At that point, we might detect them with radar, or we might not notice them until after they land, depending on the location.
If there are using a form of space-time distortion to travel, then we wouldn't detect them at all. The best we can hope for is to see the distortions as they appear in orbit above us.
Don't you watch the X-Files?
Politics is Treachery, Religion is Brainwashing
While we have loads of amateurs that look to the skies every day for fun, they'd be lucky if they spotted a fleet of aliens about to lay claim to our resources.
We have so many blind spots around the world, especially in the southern areas of the planet.
Then there is the entire "back-side" of the planet, the side where there are no continents, just a scattering of islands like Hawaii and such.
That whole area is pretty damn blind besides a few professional run satellites.
Even these large telescopes have a pretty narrow range, and take a while to scan the whole sky over. They also move quite slowly by design, so couldn't be set to scan the sky quickly.
Smaller ones have less of a problem doing that, but also probably lack the clarity or ability to see infrared, which would likely spot them far easier as they come closer, as they fall out of warp or whatever, there is going to be some energy signature unless their ships surface is made out of a one-way material to absorb all energy known to man. (we made a partial one-way EM trap before using metamaterials which was experimental at best)
Needless to say, it won't go like any of those films.
A species capable of interstellar travel, even through generation ships, would be heavily advanced. A good 300-500 years beyond us in progression. (as a whole, we could totally do all these things in less than 100 if we ditched so much of our society and focused everything in to said tech, but that isn't realistic)
If we spot an alien, good chance we are already dead.
Go see Randall, he's a specialist on this kind of subject. https://what-if.xkcd.com/
We do not. We have detectors for big honking stellar explosions. If a bunch of objects 200m across were as close as the lunar orbit, if we knew exactly where to look, it is unlikely we could really distinguish them from rocks.
This is the effect of atmospheric seeing on the Moon. http://upload.wikimedia.org/wikipedia/commons/e/ef/Seeing_Moon.gif
How far across is that crater? 200km.
Who do you actually think built the pyramids? People with sticks and stones? Who built megalithic stone walls that weigh hundreds or thousands of tons? Folks, we are alien and a brilliant experiment by some distant aliens. If you are in denial because you still believe in some mystic texts from some scriptures. Then you have missed the points those text actually made. So many signs point to humans being helped for thousands of years by higher intellect. We have just been too stupid to realize it.
First assumption: for the sake of discussion, how much are we going to "break reality" ? I mean, you said "jump" into our solar system - this assumes physics can provide a life-supporting model past our relativity. So I'll try to keep it gritty, otherwise anything could really happen - why not jumping directly next to the designed target? This might also affect why would an alien fleet or spaceship come so close to our planet.
So, the first assumption is: this spacefaring civilization is using technologies we have "in the works" - nuclear reactions as propulsion, for instance, and sub-light speed travel.
Second assumption: this type of travel is extremely slow and requires something akin to fuel.
Third assumption (and this goes a little past the question): if their spacecraft is sailing with a mission, it should mean that the civilization operating it would have solved the time scale problem - either their lifespans are way longer than ours, or their culture-technology has allowed them to transcend some of the limits nature gave them.
This being said: we'd start seeing patterns of radiation bursts somewhere along the horizon. Cross-checking with other space satellites, once the possibility of a pattern is established, would give us some headstart on their position and trajectory. Decades, probably more if their radiation signature was evident enough.
Now, the problem becomes: why would a space faring, biologically transcendent civilization want to destroy life on other planets?
Another batch of assumptions are needed.
Would this be a pioneering spacecraft exploring unknown parts of space, or would it be a drone exploring a mapped zone? Would it be unique or mass-produced? Would it be a civilian or a military craft?
Building something as massive as an unique pioneering military craft, thinking along the lines of logic that describe our society, a whole planet would be needed to design, develop and man such a vessel. It would need cutting edge technology, a huge amount of resources, and top talent - it would be this civilization's new milestone. Self preservation would be mission critical, therefore it should have means to restock its fuel supplies without the need of conflicts. It would probably have weapons but would never engage in battle, it should have proper long range scan systems to avoid threats (from radiation bursts to asteroid showers). So why pick a fight you don't know you've already won?
And the biological matter of the issue: you wouldn't want to make contact with other atmospheres' micro-organisms before making sure they won't destroy your biology. Should such a vessel be equipped with weapons, they would be designed to turn a planet into nothing, no half measures. It just woulnd't make sense.
But - going past the question - why would a transcendent civilization, who can successfuly develop a space program that allows them to travel so far from home, compromise its project by having unnecessary conflicts? It would be more reasonable to have a "planet-grinder" hatch to harvest radioactive materials ("fuel") and avoid other life forms altogether - contact would need a mass-produced design, a program including expendable crews and ships, and -last but not least- a real need to do it besides curiosity.
I went a little bit over.
Assuming realistic (for our physics) conditions, I think we would see them. I don't think they'd be a threat to us.
An alien invasion could be detected by satellite control radar for earth orbit. However, if they use stealth technology. We would only be able to see them after landing. If they try to infiltrate us by replacing one by one with remote controlled automatons, then we would see that only on a personal level (at least in the West, because we normally do not care about our neighbors that much).
However, it is totally stupid to think that any alien able to travel to the stars requires our planet.
WTF does that even mean? It is useless speculating about what is unknown or is fiction.
That said, if they were arriving through more conventional means, we would simply see them: some mode of optical detection such as star occultation, sunlight glints, drive flares, and eventually just flat out seeing them via telescope (assuming we were looking).
Also we could hear them: energy discharge from drives, EM transmissions... assuming they communicate as we do.
So far as I know there are no deep space facing military radars - I once worked at the Maui Space Surveillance Site in Hawaii: basically the place is an Air Force observatory with awesome optical trackers and some laser tracking facilities. No massive radars pointing at Alpha Centauri.
Maybe we would get lucking with some ballistic missile early warning radars... but they would be fairly close in at that point.
I am very small, utmostly microscopic.
We do not. We have detectors for big honking stellar explosions. If a bunch of objects 200m across were as close as the lunar orbit, if we knew exactly where to look, it is unlikely we could really distinguish them from rocks.
They might even be rocks. A 200m rock makes a very effective Kenetic Kill round. A 200m chunk of ice is probably going to be even harder to see, but still rates in the tens of MT range.
What was the movie?
Since we are "enlightened" and no longer believe the myths of the wrath of the gods, we have to substitute with *another* imaginary all-powerful foe?
What material basis would these aliens have for this amazing technology and power that we "wouldn't stand a chance"?
It's the same 90ish stable chemical elements across the universe, the same fundamental forces. They won't have any stronger materials or more powerful propulsion than anything we can think up. It's gotta be made of matter. And since it does, and there's no force fields, tractor beams, or other imaginary weapons, well so what?
And if these aliens somehow are able to cross interstellar distances given slower than light, actual physical reality, they'd have plenty of real resources at their disposal and they certainly wouldn't expend petajoules and kiloyears just to come here, which is just another planet made of the same stuff they already have plenty of!
What are they gonna do? Send their equivalent of Virgin Galactic over here? Use the universal translator to threaten us? By which time every FPSRussia wannabe will open fire with perfectly fine and powerful projectile weaponry and it's going to be over just like that!
Hollywood is not a substitute for actual knowledge you delusional Space Nutters!
...aliens detect YOU!
Always remember, if a species figured out interstellar flight, then they are centuries ahead of us in technology. It would be the equivalent of monkeys with rocks against stealth bombers. Except.... the monkeys do have a weapon that would decimate nearly anything any alien race could come up with. It's a horrible weapon, and would probably leave the planet useless..
Dig deep holes, put a nuclear bomb at the bottom of the hole, and cap it off with the biggest heaviest single piece steel plug we can find. Basically we are making a Nuclear canon and using the earth as a gun. When you detonate the bomb, the steel plug will be thrown with so much energy that it will destroy nearly anything on it's way through it. And yes if you did things right you could take out giant indestructable ships in orbit with this, you just have to wait for the ship to go overhead.
http://en.wikipedia.org/wiki/O...
Do not look at laser with remaining good eye.
"Things Only Slashdot (and maybe io9) Readers Worry About".
But consider this: the Chinese eat ducks. #ToServeMan
All the assumes that an invader would be perhaps biological and probably macroscopic. Assuming for the moment no faster than light travel and no magical energy sources. This means that travelling between stars will take a long time and need lots of energy. So mass and biological lifespans are a huge factor, the smaller the mass and the longer the passenger lives, the faster it can be pushed with less energy, relativistically speaking...
Today in the near earth environment we can track things larger than a baseball travelling at orbital velocities with existing NORAD space tracking. But anything smaller or faster or further away, forget it. Therefore I wonder if we would even know should the invader consisted of a cloud of nano-machines released from a micro-probe that had travelled here at near light speed.
Once the invader was here, floating down from the stratosphere scanning for useful biological machines with large enough brains we would not even be aware. Save perhaps for a spectacular sunset or two. The first sign that we had been invaded would be perhaps a sudden breakout or global cooperation and perhaps the appearance of apparently physic abilities and heightened regenerative abilities in infected subjects. It would only be much-much later that any remaining uninfected individuals would see the real purpose, when a new international space plan is put into place to send AI nano-machines as avatars for ourselves to the nearest stars.
This question is so loaded it's pointless. You may as well as "when did the aliens stop beating their wives?" You have to assume, axiomatically, that they would have any reason to invade, but that's absurd. It's even self contradictory. The nature of the challenge put forward is that aliens have mad advanced technology... so what would they invade for? It's like a person from affluent western society giving up their life and flying to the other side of the world, to a desert island, to beat up a native, take their shack.. just because they have a tree that grows fruit you like. IT MAKES NO SENSE. In fact that makes even more sense than alien invasion because aliens will have evolved in a completely different eco-system an wouldn't consider our's very inviting. This is just another zombie apocalypse escapist fantasy distracting people from real looming apocalypses that are too boring to worry about.
Nice try advanced scout party. You slipped through but I doubt the armada will fair as well.
They always ask to see our leader.
"Sometimes I think the surest sign that intelligent life exists elsewhere in the universe is that none of it has tried to contact us."
Sanity is the trademark of a weak mind. -- Mark Harrold
If they are used in such a manner, then the question is just one of near-Earth object detection, of which there are good FAQ's a Google search away.
If there are aliens that actually are living rocks, I'm either not at all worried or completely terrified, and either way the detection is useless.
Don't worry - the aliens are waiting for us to finish the process of nuclear disarmament - then it will be safe to proceed with their invasion.
There is no God, and Dirac is his prophet.
A civilization advanced enough to get here from another star would have better control of matter than we do. Coming here would be pointless; all we have to offer is just more carbon, oxygen and iron -- who cares? Cheaper to harvest atoms and energy more local to them and organize them beneficially.
Often we are assuming that the aliens will be these green men, or god-like creatures, but basically a single species, but more powerful, or smarter or whatever then we are. Does it have to be? For years now rocket scientists have been concerned about contamination of Mars etc by our probes, and contamination of any returning probes by extraterrestrial microorganisms.
As a fictional example of an invasion by alien _ecology_, you can do much worse then read David Jarrod's (of "Trouble with Tribbles" fame) Chtorr series. Or you could just look at how the zebra mussels are taking over the Great Lakes, or Burmese pythons are taking over Florida's Everglades.
What is the point of this? Obviously we detect nothing and get wiped out or detect it like any normal mass in orbit and have no ability to do anything about it.
Really pointless and stupid question.
According to Snowden, the NSA has AIDS (Alien Invasion Detection System). The exact particulars are classified but the amount of data collected should serve to warn us in plenty of time to mount a defense. No worries.
Any technology that enables aliens to visit us would be so advanced that we could never combat it at all. But the good news is that any such advanced beings would also have no need for us or anything we possess. Concepts like wealth would probably not exist in such a race and ideas like eating may also have been reduced to some sort of technology that disallowed ingesting what we call food. The technology possessed by such beings is beyond our imagination. To us a comparison might be that God dropped in on us and had a real craving for a quarter pounder with cheese and some of those skinny french fries.
There are lots of sci-fi stories about aliens invading, for all sorts of reasons. Sex, Water, Engergy, what not.
But really, why would they? There aren't any rare elements on earth you cannot get to easier any where else. If our theories about life is correct, the universe is filled with life. The only odd thing about the earth is plate tectonics.
If you have the technology to travel between the stars, there is nothing on earth you'd need, except maybe sex. :-)
You do realize that all these ideas come from our relatively limited technological capabilities, plus a heavy dose of fiction, don't you? Any actual encounter would force us to reset all our expectations pretty much instantly. My advice would be to stay away from fiction, and focus on solving some real problems down here instead.
This is like asking if you could detect an F16 coming at your house -- by the time you hear it it's too late and the pilot is on the ground having a second cup of coffee. If you happen to see it your AR isn't going to do squat against it. If they can get here it won't matter whether we see them arrive or not. Either they will have a tremendous energy source (assuming relativity holds) or they will be way smarter than we are (to get around relativistic energy limitations).
My question is how good are we at the moment in detecting an alien ship/fleet that jumps into our solar system
I would say next to none at all. Nobody wants to foot the bill. NASA is mandated to track all "Near Earth Objects" larger than 1km in diameter, and they keep getting their budget slashed. So 95% of the ones you hear about in the news are being found by volunteers and other amateur astronomers.
They'd send a couple of capsules the size of a nickle into our atmosphere from outside the ort cloud. They'd either be laced with a virus to kill us all, antimater or some other yet-to-be-discovered nastiness and it'd be all over in seconds. We'd have no idea if they didn't want us to have one.
That being said, if the craft was travelling at light speed you could not see it. The light emitted from the front surface at near the speed of light would be so highly blue shifted that it would be above or in the gamaray zone, but not a particularly powerful source nor a single burst that would then trigger sensors like SWIFT, or Fermi, but might be visible to HESS if they do comparative imaging over time to detect moving gammaray objects *across* its field of view. If its coming right at us probably not.
Due to the laws of physics I can still sleep well at night.
To start with our species are not what I would call robust. Look at the narrow range of altitude, pressure and temperature that it can work in. I would call it rather flimsy.
I cannot logically say that we are the only species in the universe, nor is it very observable. Any discussions of technology and capabilities is simply silly since our grasp of what the laws of the universe are is limited to what we have accomplished on Earth for a very short while. An alien force could have spent millions of years developing technology that is so far ahead that we could easily mistake them for gods, as far as their capabilities goes.
Nuclear weapons?! Why would they use such primitive and impractical weapons? No I'm sure would they arrive they would so totally blow our minds, capability wise it would not be funny.
We are biased to consider the question in current technology terms.. we have no other view point.
Jules Verne would have a different opinion from H.G. Wells for example, from Robert Goddard, from Einstein from Hawking.
Currently.. interstellar would involve either a close pass by a comet or stellar system to ours.. or using a Higgs Boson like transporter to "lens" an object from one solar system to another over a gravitational wake.. more or less "riding or surfing a graviton field sling shot" so that no fuel would be required and would end up at close to zero relative velocity in a nice solar obit once they arrived. With that in mind unless we had gravity detectors.. we wouldn't notice very much.
We likely wouldn't even realize we were under attack until it was far too late to do anything.
If we reject the OPs "jumping in" and assume the statement is from a person who's watched too much sci-fi, what would we see as the alien fleet arrives?
Well, the first question is, what methods do we know of right now that could work for the alien's engines?
There are :
1. Nuclear salt water or nuclear pulse (orion drive)
2. Fission Fragment
3. Fusion
4. Black holes
5. Antimatter annihilation
6. Some kind of sci fi method to just release the rest mass as energy in ordinary matter without the antimatter needed.
Number 1 is some variant on a fission bomb propelling the ship. A couple percent of the speed of light, tops. Number 2 and 3 have the problem of pathetically low thrust although high isp. Black holes depends upon assumptions about a black hole that makes them movable (they have to be electrically chargeable) and constructible (you need solar system sized mass drivers to accelerate metal rods to slam into each other at a sliver below the speed of light to form the black hole). But, they are a near perfect form of engine - you feed the black hole a particle beam of ordinary matter, collected by ramscoop, and you get back gamma rays that your enormous ship reflects like a parabolic dish. Antimatter annihilation is similar to black holes except it requires you to carry all your antimatter with you, and it's immensely difficult to avoid blowing up the ship.
Anyways, all these methods have a common factor. All of them will release a flare of gamma rays as the alien fleet decelerates. The alien fleet probably would not even use their engines except to maintain speed and slow down - they'd probably use a stream of mass accelerated pellets launched by mass drivers in their starting system to reach their cruising speed.
Also, all these methods have the problem that they provide pathetically low acceleration. 0.1 g (1 m/s^2) at best, a tiny fraction of that at worst. Realistically, the alien fleet will be decelerating for about 10 years to centuries. We'd be able to see the gamma ray flare from this for many years if a gamma ray telescope is pointed the right way.
As for vulnerability - they'd be immensely vulnerable upon arrival. Not to the technology we have now, but technology we could probably develop relatively rapidly. The alien ships would not have high acceleration engines able to avoid incoming fire or outmaneuver attackers because that kind of engine is too inefficient for interstellar travel. Their ship is unlikely to have anything on it more than a payload of factories and data, because the mass for weapons or engines is too much.
Their plan would almost certainly have to involve decelerating to rest near an object with some mass in our solar system, preferably one close enough to the star so that solar energy is available. One of the various comets or asteroids would do fine. They'd eat the rocks, turning it into more equipment, and essentially regrowing all their technology and infrastructure from the actual starship seed payload.
This is when you jump them. You need an orion drive space battlewagon to show up before the aliens eat enough rocks to build something to fight with.
No rocks form space
No nukes
No lasers
No armada
Just a nasty virus which already have plenty off and that's all it takes to get rid of any population on a planet.
If you can get here from somewhere you can gently nudge a big asteroid, so no big fleet just a modest size space probe with an ion drive on a big comet. Something our tech could almost do now. Mostly undetectable, big comets are only detectable when they are in the inner solar system and probes only if they are broadcasting toward earth.
So a solid no, and a civilization ending event that looks like bad luck.
Ask the Indians how it went for them.
You won't see any aliens. Nor will your children. Or theirs, or theirs to the next thousands or more of generations. Why? Imagine all the grains of sand on a beach. Pick up one. That's how long we have been here compared to the universe. We have not been here long enough to even be a miniscule blip in time to have encountered aliens. All the SETI projects and their like searching for aliens is a waste of time. No pun intended. Give it a few hundred million more years.
We have already proved that humanity is lucky in the sense, that we have been able to detect rogue rocks flying around our solar system. Not all of them and most of the time too late to do anything about it they were lethal. I would not rule out that we have "no chance" of knowing, but its highly likely we have no chance.
As far as invasion, typical "war tactics" which I am sure earthlings are not the first to use, would be performed. Research, scouting, and observation will have been done to our planet and our inhabitants ( I am sure this has happened already, and still is happening). The results there of, would reveal to the invaders what our weaknesses are as well as what we can do. Thus they would formulate a plan that will result in victory with little to no loss on their part. Then they can reap the planet of its valuable plastic!
Perhaps the speculations are correct and humanity DOES have non-earthling allies or relationships, which then we could ask for help against whatever invading species is coming our way. (We can pay the allies with precious plastic).
You would be able to tell because the background music would get more dramatic whenever you looked into the night sky.
#naabhaprzrag, #sverubfr-000, #agi-fcbafberq, negvpyr[pynff*=' negvpyr-ary-'] { qvfcynl: abar !vzcbegnag; }
Obviously if there were an invasion fleet looming around our planet, it would first be detected by some misanthropic kid with a telescope. That would be the easy part. Then the kid would have to convince his alcoholic, ex-Air Force father of the impending invasion. Then the father would have to swallow his pride and contact his old partner (the one who was promoted after turning in the father for doing something that was technically wrong, but was undeniably the honorable thing to do in the situation), who now just-so-happens to head a clandestine wing of the military specialized in dealing with alien invaders. Obviously.
Thats the real reason for installing them, doncha know.
We almost certainly wouldn't see the alien ships until they were in orbit, particularly if they approached from one of the solar polls rather than in the ecliptic plane (the geometric plane that contains the planets and asteroids).
We can get radar observations from objects as far away as Saturn, *but we have to already know they're there* to observe them with radar astronomy, and they have to be quite large -- 100s of km across. Even as far away as the moon an object would have to be a km across to be caught on radar. So we don't send radar signals willy-nilly into space unless we know the object is already there. The way we detect near-Earth objects like asteroids is optically, looking for "stars" that move across photos taken in succession. But this might not detect the approaching fleet at all, even if it were approaching along the ecliptic; and if it did it's likely that we wouldn't notice for days. The system isn't designed to detect fast spacecraft maneuvering toward Earth; it's designed to detect rocks more or less traveling along with us that wander into our gravity well.
Of course all this depends on your assumptions about the ships. If the ships were as big as the Moon, we'd notice them from a few AU away. If they emitted exhaust plumes that were bright as Jupiter, we might even see them with our naked eyes well before they reached orbit. But if they're only a few km across and not fantastically bright, chances are we wouldn't notice them until they showed up on our orbital debris tracking system. Even then we wouldn't necessarily notice right away. The system isn't a real-time early-warning system. We'd probably still be chasing down the "glitch" in our systems when the first aliens landed.
Now I wanted to answer your question, because it raises and almighty rant in me that I just have to get out: is it too much to ask that writers of "science fiction" have a *little* science knowledge and a more-than-room-temperature IQ? For Pete's sake the energy in life forms (at least Earth ones) is solar radiation converted into chemical bonds. The notion that a spacefaring species would have to transport those chemical bonds across insterstellar distances for its *energy* needs is preposterous. The notion that this would net them any usable energy is nearly as preposterous. Would you send a log into orbit to fire a boiler?
It's not just second string popular sci-fi that has this problem. Both the J.J. Abrams Star Trek movies show a complete lack of thinking about the geometry of space. In the last movie the Enterprise is chased across interstellar space only to be stopped 240,000 km from Earth, and they're *right by the Moon*. Yes, 240,000 km is roughly the radius of the Moon's orbit, but the chance you approached from some random direction and happened to end up right by the moon is minuscule, even if you're at the right distance. And then when they lose power they *instantly* fall *straight down* into the Earth's atmosphere.
Yeah, I understand it's the storytelling that counts, but it matters if the scenario is just plain stupid.
Post may contain irony: discontinue use if experiencing mood swings, nausea or elevated blood pressure.
You *do* know why it's hard to see rocks in space, right?
At the distances you're discussing, it has nothing to do with their size. It has to do with the fact that they're very nearly as cold and 'dark' as space itself. Starships wouldn't be, or their occupants would be long-since frozen. If the occupants aren't frozen, and the starships aren't brighter than the background of space in at *least* the infrared part of the spectrum, then the ships are autoclaves, and their occupants would be long-since *baked*.
These are the three options for long-distance space travel:
1) Use/generate so little power that your ship cools to background levels, and freeze.
2) Insulate your ship so that it's *exterior* remains cool to background levels, and bake.
3) Emit heat, and be easily detectable at long ranges.
To me the best argument against an invasion is this (not mine, of course): with all the incredible technology they would have, they would find what they need in millions best places in the galaxy. Why should they chose one little planet among billions ones, and just the rare one that's hosting life? Unless they are sadist and enjoy killing living beings, of course, but that would be a too much expensive hobby even for them, I guess...
Well, that assumes Star Trek/Wars levels of magical glowing technology, where traveling 500 light-years is only slightly more involved than traveling 5 light-years. Suppose instead they're, say, a third of the way between Neil Armstrong and James T. Kirk. They can travel interstellar distances, but only barely. And, fuck our luck, it turns out they live within a dozen or so light-years of Earth. Maybe they didn't even seek us out, they just sent out missions to all the nearby star systems, and we were on the list.
In other words, what if it's our dumb luck to be within a few light-years of some aliens who are just a century or two ahead of us, developmentally?
The upside of this conjecture is that it would be much more feasible for humans to repel an invasion, if necessary. We might not be able to make a trench run at the Death Star, but shooting down nuclear weapons coming from space is something we're already working on.
...for our puny weapons. I've got a board with a nail in it!
Earth has nothing to offer a far more advanced species. Minerals, water, etc. are far more abundant in space. Slaves need to eat and sleep so manufacturing robots would be far more efficient to make things. Proteins can be grown to provide more than enough food. We're probably not much more than a curiosity to a more advanced civilization.
if their ship is the size of the death star, and the whole thing is covered in neon signs advertising Darth Vader Brand Prosthetics, and Axe Imperial Deoderant (for the stormtrooper looking for that sexy cadet)
then, it's probably not hard for an amateur astronomer to happen to see it. Especially if it happens to cross near something that amateur astronomers like to look at, like planets, known bright stars, etc.
likewise, if coming in from hyperspce triggers a small supernova worth of electro-magnetic waves, then every radio astronomy telescope on the planet, will detect them.
OTOH, if they have a ship that is only the size of LA, and the ship isn't trying to advertise itself, (or thrusting with a really obvious plume of exhaust), then its about as likely to be seen as any near earth object. We've had a few decades of modern tech looking for those, and have found well under 10 percent. If you want to find it in the first month since the aliens appear, I'd say less than 1 percent chance.
Obviously.
A better question would be how we could detect the activities of extraterrestrials who have been visiting Earth routinely for a very long time, and whether it's even in our interest to do so.
Nope it's too late - they are already here having strategically taken over Comcasts call center in a bid to drive us off the planet.
We make some discovery that unifies harvesting gravity for power but our motivation is still happiness and health. As you can tell from most alien invasions is the aliens are mean, not happy. What motivation does any life form have for dominating a universe?
Owing to the vast distances between planets likely to have intelligent life, machines are likely the only alien things you'll ever see. Owing to the energy expense of traveling vast distances, they will likely be very tiny machines, like nanobots from science fiction. Due to the speed of light and hence radio communications, the machines won't be able to be in contact with their makers, at least without significant transmission delays; therefore, the machines will likely possess advanced intelligence on their own.
Having said all that, we could very easily have been invaded many times over by intelligent nanobots from space. They would have been completely undetectable until maybe a few decades ago and perhaps are clever enough to continue to escape detection. Our planet is highly unexplored. We've only cataloged a tiny percentage of life. We've barely glimpsed into the deep oceans. We're also quite ignorant about the underground, as we're drilling for oil right now and have no clue what might even cause an earthquake (so we're ignorant about not just tiny things, but features gigantic enough (possibly miles in diameter) to produce earthquakes).
In fact, the very cells in our bodies could be invaded by aliens disguised inside bacteria or viruses. How many of these bacteria and viruses have we even looked at under a microscope? We have trillions of these organisms. Imagine the power of one million compute nodes that could hide in less than 1% of our cells. And right under our noses is just one possibility among many.
Maybe the world is like the Matrix, except the robots are tiny instead of massive with a little bit of Scientology thrown in, where our bodies have an alien presence inside of them (but not the part about stealing people's money).
Beyond that, what it the point of your post?
Any race advanced enough to travel here to invade will have capabilities way beyond anything we could hope to combat or detect. I would imagine the first sign you would have would be if you were one of the lucky ones to see half the world wiped out a few seconds before you yourself were removed from this mortal realm.
Well, I think when they start posting on slashdot asking about the possibility of detection, that's a pretty good first sign.
The earth has millions of different microbe-sized species. Many of them growing and living on and in us as well as every other creature on the planet. I can't believe an alien race won't have the same ecological setup, just different microbes. So we'll detect alien contact when new plagues sweep through some species, human, animal, plant, or otherwise. In turn, just like in Well's "War of the Worlds" some germ on earth will wipe out the alien invaders. Single celled creatures are voracious, relentless and constantly reproducing. It will be a bacteria (maybe a virus) that will escape quarantine and consume some species or many related species and cause great harm, possibly disaster and ecological collapse that will signal alien contact.
I think that we'll find that the only safe way to communicate with any alien race will be by telecommunications. Direct, physical contact will have too much risk of unintentional infection. Likewise, trade will only be in ideas.
maybe those "Gamma Ray Bursts" and "supernovas" are star systems being eliminated for defying the Emperor. Just hope we're not in the queue.
we can see about 1~2% of the sky with radio telescopes, etc. Most of our infrastructure is pointed back down at us.
Depends on too many different assumptions about the alien technology.
If they were ships that had to use reaction drives when their magic FTL wasn't working, we'd notice them pretty quickly.
Any ship big enough to be interesting would need a drive that expends enough reaction mass to move it to interesting places. MHD drives, Nuke-Thermal, big Ion engines, chemical rockets, god forbid Pulsed bombs or Valkyrie Nuclear or anti-matter annihilation torches, would be visible at 2 AU distances at least. (if you were looking in the right spot.) Most of those would also put out a good deal of EM radation or outright gamma shine which would be impossible to hide.
If it was something small and cold, a cloud of von-neumman assemblers that never expended any reaction mass, until just before hitting our atmosphere, we could potentially never see them.
If the aliens just wanted us gone, and had the energies required for interstellar travel, we'd be toast. A couple inert multi-ton masses of carbon fiber or iron fillings, sped up to 1/2 of C, put into the planet, would ruin the current biosphere for a good long while, and kill anyone within LOS of their reentry. Two or three dozen of them, and survival of anything on the surface, or the photosynthetic ecosystem is gone. We'd never see it coming. Pif.
Chances are they will treat us as a holiday destination, or a research station. Chances are they wont be that interested in the earth, you people are so planetist
What's up with this "we" shit? I plan on siding with the Aliens and telling them how tasty all you all are with a bit of Cajun seasoning! I for one welcome our alien invading overloads!
We would notice 1 or more extra moons!
Okay, this may never get read, but a few problems with your post...
- Judging from IR images of very warm planets, even hot objects aren't going to be so noticeable. ...pretty sure there's more, but as you're AC and not modded up, and this thread has gotten pretty big, probably no point in writing more.
- Angular resolution really is a bitch... you really trying to tell me that thermal radiation of an object a few hundred meters across is so extensive that we could see it as far away as the Moon?
- Our coverage of IR is much worse than visual spectrum, because of water vapor in the atmosphere. If you gave us exact coordinates, which you wouldn't have, you probably couldn't get telescope time anywhere that could measure it.
A) The aliens are openly hostile, either through malice or ambivalence. Here, the risk is that their actions upon discovering our planet quickly render the planet uninhabitable (either because they mine it for resources, wipe us out with a death ray, or build an interstellar bypass through our solar system). We would not win in this encounter.
B) The aliens are openly friendly. This could mean we get uplifted, or get to open trade deals, and/or have all our worldly issues quickly resolved for the better. Maybe this is too optimistic, but I'd like to think that an advanced alien society would also have highly advanced morals which would recognize all life as having a right to live.
C) The aliens are ambivalent or outright ignoring us. This is likely the situation we are actually in. With the Drake equation and the Fermi paradox well understood, I feel it is most likely possible that any advanced alien society that has detected us recognizes that our little world is simply not worth disturbing. Maybe we haven't met the technological level to justify meeting us, or maybe we live in the equivalent of a refuge or reserve. Or maybe the aliens that did survive have simply gotten so advanced that they would look like gods to us, and we would be ants to them. When was the last time you bothered paying attention to an ant? Or maybe you simply can't travel faster than the speed of light so no one bothers. Or maybe we're it, there are no aliens, it's just us.
Frankly, if it indeed turns out that the Universe isn't 13.8 billion years old, and is instead actually timeless, C is the most likely to be true. 13.8 billion years is easily enough time for a society to produce the perfect moral code, so clearly more time makes C even more likely. The fact that we haven't been visited in any significant way (no spaceships with ambassadors landing on the white house lawn) points to C being the most likely reason.
Some alien scouts have recently landed on earth. Right now, the alien scounts are investigating the best way to invade earth. They have found 'humans', and learned that humans use something called 'internet' to ask for information.
The aliens were detected when they submitted a question to slashdot to investigate if their invasion would be detected.
...we can't even detect small asteroids approaching in the tens of thousands (or more?). How in the world do we stand a shot today of detecting aliens that are attempting to be stealthy?
Same reason I cringe at Star Trek battle scenes. I I was Picard (or Worf) I would just beam a big blob of plasma straight onto the enemy bridge. Or beam their warp core out. Or just beam them all straight off their ship into a holding cell. Or to the inside of a star. OR beam the enemy warp core containment into space. Why even launch a photon torpedo? Just beam it there ASAP. I could go on and on on on.
If enemy shields is a problem just beam the photon torpedoes en masse to a point 1 second before impact on their shilds. They can't evade and you can saturate the shield with missiles until it collapses. And then go beaming away.
A transporter beam a la Star Trek is pretty much the ultimate weapon.
Breaking Bad has a classic piece of dialogue between Badger and Skinny Pete about this.
http://www.cinemablend.com/tel...
The dangers of excessive individualism are nothing compared to the oppressiveness of excessive collectivism
It took NASA about 20 years to find 90% of NEO asteroids bigger than 1KM in diameter. and most of those more than 100M... so if The Aliens have been stalking earth for the last decade trying to match orbit, and have a ship more than 1KM in diameter, then there's a 50% chance that we've mistaken them for an asteroid.
Sometimes boldness is in fashion. Sometimes only the brave will be bold.
Easy. They will not have valid credit cards.
1) There would be no reason for a species so advanced to invade us for resources. There are lots of resources in the universe.
The only realistic reason to wipe us out is if they see us being a potential threat in the future. Which clearly, if they can space jump to us, we're a long way off being any sort of threat.
2) If there are intelligent aliens in our neighbourhood of the galaxy we're probably already being watched. They'd probably have the technology to send micro machines to record everything we do.
Right now there is probably a tiny machine the size of a dust particle recording what you type on your computer. It's almost certain the aliens watch you picking your nose and take samples of your farts for analysis.
Spotting them first?
Not bloody likely
The only way we could see them before they got here is If for some reason do to how their long distance space travel is a fair bit slower than light..
If its faster than light forget it.. Because they would be here Before the light or radio signatures got here..
Also Unless there is something really strange like a few stories that have been written Where faster than light was found before other tech.
they would have far superior ships and weapons to us..
We are already to pretty advanced planes, drones, mach 4 planes, nukes, rail guns, and weaponized lasers..
And We are No where Near getting to a double digit percentage of the sped of light..
Think of how far we will be by the time we can do real interstellar travel...
So Anyone that makes it here..
Think of how far ahead they will be..
So we best hope our luck holds a while longer..
Seeing as no one in human history has come by that wanted to wipe us out..
Doesn't mean no one will ever..
Cause just like a school yard or a big city.. We can't depend on Everyone out there being friendly..
... Will destroy themselves centuries before they can come and kill us.
Unless there is technology that we can only dream of today, like warp propulsion, our current physics can't provide us even with the means to power a warp drive.
Even with the most advanced conceivable nuclear ion propulsion, coming with anything over a few dozen tons from the closest solar system is essentially inconceivable.
If mankind decided to put together a large enough spaceship to send men to the nearest goldilock planet on another solar system would require all of earth to pool together massive resources, like decades worth of current space budget of all of earth's planets combined.
So while it highly likely there are many planets with intelligent life in the milky way, that civilization would first have to fully unite itself before they could dream about launching a spaceship able to just visit earth. In fact should their intents be military, its far more likely they would land on Mars, and use Martian resources to increase their popullation and manufacturing resources before trying to attack us.
Its all about understanding DeltaV, Specific Impulse and other utterly inconvenient scientific facts that make sending humans to other solar systems impossible today (hence the same challenges for the inverse trip). The rest is just Sci Fi.
Maybe the next Einstein will revolutionize Physics like the last one and unleash practical, compact, lightweight fusion to power and solve warp drive physics to use that power.
Take Ion thrusters. In order to be very efficient, it pushes individual little molecules at very high speeds, typically using electricity from solar panels.
Very high ISP, but tiny thrust. That good old solar energy problem, low energy density.
If we could increase ion thrust energy by a factor of a thousand, we would need monster energy sources to generate that kind of power, but if those are too heavy, the whole advantage of reducing the fuel used is wasted by the heavier energy source. So far there has been no viable electricity source that was light enough to replace solar cells to power an ion drive efficiently (for interplanetary level missions).
Plus the most efficient propellants are heavy noble gasses, like Xenon and Krypton, both very hard to come by (one predictable source for them would be nuclear reactors, but solid fuel reactors make harvesting those complicated, can't drain the gasses in realtime).
Some one will suggest plutonium 238 type nuclear thermal generators, but those only last one century, their power drops precipitously due to half life effect. It has to be a nuclear fusion / fission power source whose fuel can be stowed aboard and be good to use 10000 years later.
Oh, and the ship must be big enough we must send families that will live and die aboard the ship. Those landing on the other side will be dozens to hundreds of generations later.
HFT (High-Frequency Trading) technology applied to detection and defense: discuss amongst yourselves.
Scientists and Philosophers at SETI believe that an alien race sufficiently advanced to visit our solar system would have evolved beyond biological life, becoming cyborg or truly artificial life. It's a logical progression from computing to AI to re-engineering their own life forms, and we are likely headed that way if we survive. I blogged about it, as evidence for my own assertion that Web 3.0 will involve a direct neural connection to the internet, a first step in melding human and artificial intelligence. Philosopher Susan Schneider has proposed that any alien race we are likely to counter are probably BISAs: Biologically-Inspired Superintelligent Agents. One reason SETI has not produced results is because we have been looking for biological life and consciousness. And what would any sane and advanced alien civilization want with our messy biological self-destructive race, and our ruined planet, anyway? I think they stay the hell away from us, like we have Ebola. I have also considered that UFOs may be time travelers, perhaps from our own future?
aliens are already here. who else would promote the use of radiation = endangering all life on the entire planet just to boil water?
look out for mandatory vaccinations too! when the exercise of free will is outlawed that IS a "take over"!
Since we are just beginning to appreciate the tenacity of life itself, currently we only have ourselves to look upon for some precedent regarding intelligent extraterrestrial life. At this point in developed countries' cultures much of the expenditure is on military spending. We have not progressed past our warlike tendencies. It has been suggested that, were an alien race to make themselves known to us, that they would have transcended their cultural tendency towards war expenditures and spent more time on exploration to the extent that would allow them intergalactic travel. In the ability to see other planets, Kepler, despite being hobbled by its pointing wheels, has already given four or more years of planetary data and new discoveries of planets within the habitable zone are always being found. Recently the question of what we consider to be habitable has even been revised. For closer objects, I think we could be doing better; not necessarily for flying saucers but to safeguard our planet against things such as Chelyabinsk or worse. Asteroid 2014 BA14 was discovered by an independent group in Spain by using equipment by a grant from the Planetary Society so this was no large government funding this project. The asteroid is 250 feet (45 meters) in diameter so that should give you an indication of what a small but dedicated team of researchers can accomplish. The problem with spotting near Earth objects, be they ETs or asteroids, is where they are in the sky and their composition. Looking towards the sun is not very successful and if the object is dark, space is dark as well, compounding the problem of seeing it, therefore infrared is a good way of spotting it. Mathematically, its very possible and plausible that there is life on other planets. How much is intelligent remains to be seen.
With things like a parasite that can change behavior, I'd say we've already been invaded and no, we haven't noticed it. (Toxoplasmosis is one example.)
Lemme guess, it didn't work because no birds. But they still would have killed for the accurate clock and camera. Show them your sextant app, and they'll show you their sex tent "app".
https://www.youtube.com/results?search_query=nasa+tether+incident
Tether incident unexpected electric overload. UFO during Live NASA transmission.
Ice debris or UFOs:
Both arguments are correct. There is both ice debris and UFOs, but they get mixed up in this clip. That is because all of them looks the same in this camera.
The issue at hand would be to detect an invasion fleet jumping in directly to our solar system. That's be an event probably releasing extreme amounts of energy. Considering it would be a fleet, I assumed it to be ships considerably larger than 200 m across, and more than a few. The reference was sci-fi movies so I gathered Star Destroyers or Independence day, Goa'uld or V motherships, i.e. kilometers across, and perhaps hundreds of them. Just the warping in millions of tons of matter into the solar system would release a gravity wave that'd be detectable. These ships will radiate enormous amounts of IR just by being lit buy the sun, not considering spill heating from the internal environment. Their propulsion would generate exotic energies, and/or release chemicals that would radiate in turn (and be harder to cloak). And if they were to communicate by something in the EM-band, that would also be detectable too, even if they were to use very focused beams, since there'd be scattering in the interplanetary dust leaving trails (like a cloud chamber, or comet trails). and the list goes on.
- Henrik
- when the Shadows descend -
FTL is impossible, per Einstein. So yes, we know that it has to use the physics in this universe.
Those who advocate genocide deserve every protection afforded by law, and none afforded by common human decency.