Do you think aliens are watching us?

Don't they have something to do ? Even if there were any other life forms in the universe, the distance is far to great to make observation/communication likely.

I don't think there is any serious evidence. If they were in fact studying us, then, as many SF stories have written they would declare us dangerous, to be avoided at all costs, because as nations we lack logic and good sense, and are likely to destroy everything including our planet. We have greedy, insane heads of state and politicians, who are o f course, when free elections are in fact available, elected by illogical, superstitious, uninformed clueless stupid voters.

nah, I wish

I doubt it. Galactical distances are enormous. There may be life forms in many places in the universe but most likely, they are living autonomous existences rather than under surveillance by aliens.

Why is there such resistance to the acceptance that there is alien life that is much more physically evolved and incomprehensibly more technologically advanced than us? Common sense tells us the universe is teeming with life. Only our ignorance limits what we think is possible.

The investment of 1,000,000 years to an intelligent life form that has existed for a billion years is trivial. And that is if 90% of light speed is a limiting factor. But transportation from one point in space time to another is not limited by our rudimentary mathematics.

We study ants and birds and chimps and mice and men to advance science and satisfy our curiosity. We have learned that to get the most accurate observation the subject should not know it's being observed. Observation changes behavior, even with elementary particles.

Now to lose all of those I didn't sway anyway, I am a pilot and I have seen, while flying one night in my private plane, a craft that defied the laws of physics. After it followed me for ten minutes I remembered I had a professional camera. Before I could point it at the clearly visible circular craft, it reversed direction without a turn and bank and was gone across the horizon in an instant. The next day multiple people claiming to seeing UFOs was reported in the local newspaper headlines.

Over and over, people bring up the distance. It is true that WE can't possibly travel, or even observe in anything close to real time over these distances.

A few hundred years ago we couldn't possibly observe or communicate with someone more than a few miles away. And the fastest we could travel was as fast as our legs, sails, or animal legs could carry us. Unless we fell from a high place. Then we could travel MUCH faster, for a short time. Seldom very productive though.

A few hundred years back, crossing an ocean was as hard as entering orbit is now. For good or bad, we are filling the skies with semi-active objects, some with US IN THEM. We have been to the moon, and landed robots on mars.

With only a couple thousand years of tech past the bronze age.

What will another couple thousand do? Remember, this solar system is Very Young. Most of the solar systems we know of are older than this one, by a lot. If there are in fact other smart critters like us out there, they may well have 10s, 100s, more? thousands of years on us.

Tech leaps. Everything we do now was fantasy at some point. Give us another big leap, maybe we find away around the universal speed limit. Maybe if there are others, they already have.

Considering astronomical distances, I think it's unlikely that aliens are watching us, and if intelligent life exists on other planets, it might even be plausible that they haven't yet developed the technology to observe space.

Depends on how far away the aliens are. Probably those most interested have just seen the first wheels.

Makes me wonder if there is fossil light reflected from Earth 66 million years ago still orbiting a black hole somewhere “nearby” that could be collected from outside the event horizon (don’t ask how) and reconstructed into images so WE can see our ancient dinosaurs. Enormously sophisticated technology? Yes, but not impossible.

A change in temperature in/on Planet Earth to assess the sort of life which could survive.

A form of intelligence has probably developed somewhere in the Universe.

The subject and the query is intriguing. The reason being, we as 'Human Beings' have been provided with our sensory bandwidths to observe/hear/feel/touch/taste, etc. only for the world that we are currently perceiving..! This is the most wonderful aspect of our Existence. Now, if we have had a switch or knob to tune our bandwidths to other dimensions, we certainly will see the other 'world'. Extending this argument, one can logically conclude that the so called 'Aliens' are possibly living in a dimensional world beyond ours and may be as aloof of our existence as we of theirs. By a quirk of bandwidths overlap or instrumental perceptions there is a strong possibilities they may observe us and we, in reciprocation, them (if reciprocity exists in that dimension). So, a strong yes on this possibility that they are observing us.!!

If the alien observers were to use gravitational lensing, how would that change Phil Plait's calculation?

Okay, Barry, good post. Everyone is obviously fixated on the lightyear distance correlation, and doing the viewing (by the aliens) through space-time as we observe it. What that leaves out is our knowledge of astro- and quantum-physics is most likely quite elementary. We think we know everything. We don't. There probably is quite a lot going on around us that we just haven't learned to "see" (learn, feel, observe) Calculating and imagining the mass of a telescope 35 lightyears across, I submit, is better brain exercise that bingewatching 1980s sitcoms. However, I think you're right. I have all the M*A*S*H episodes.

Calculations like this might be viewed by many as lost "opportunity cost," that is the time could have been used more profitably, like bingeing on a 1980's TV show. On the other hand, the detailed calculation allowed for some good information, like the angular dimension of the moon ( i would have noted, the sun to be the same, a coincidence that results in "goldilocks" frequency of solar eclipses), and a reminder of the sheer size of the universe, requiring "deus ex machina" abrogation of the laws of physics for shows like Star Trek. No, aliens (from outer space, not inhuman government agencies) are not watching us. And any hope that we will ever make contact is a fantasy. And were they somehow to get here, I guarantee that after such a long trip, they would do everything they could to be friendly and non threatening.

Rather than a almost impossible telescope I'd think a light reorganising technology of some sort might be more easy, like something that reorganises "our" light that has reached their planet back into the exact image of when it reflected of us, or dinosaurs. The math and science of that might be more difficult than building that telescope though.

The question assumes we would be sufficiently interesting for an alien to observe. It is more likely that if they have observed us, they would dismiss the observation as unimportant and go on about their daily lives, attempting to dominate the universes

I'm a huge sports fan and I love to imagine aliens watching our American Football or tennis or any sport really, and how amusing (or inscrutable) those activities might seem to them.

They are not watching us yet.

There are many narrations of encounters with “superior” beings in the course of human history, usually these have been embedded in one, or more than one, complex of religious beliefs. I think it is more probable (presumably, a very low probability) that some of these narrations are factual. Whether these might be attributed to “aliens”, i.e. physical creatures from other solar systems, is simply adding another order of magnitude to the problem. So, in short, I do not believe “aliens”, defined as embodied creatures from another planet/solar system/galaxy, are watching us. The distances are too staggeringly huge. However, this does not mean that … nobody is watching.

I cannot prognosticate which Earthly developments aliens may find most interesting, but I will hazard the guess that learning about life in the universe could be one of their intellectual pursuits. Perhaps events during our history, spanning 1914 through the late 1940s, may be interesting and instructive for aliens to review and study. This time period would include the extremely convulsive events we remember as World War I, the Great Depression and World War II. These serial events were related to a degree and alien studies may reveal valuable insights into how life on Earth manifests and copes with their survival instincts. I imagine the topic of survival is likely a top priority on any lists of pursuits composed by all life forms in the universe.

Has anyone ever considered that time may flow differently on another world. That planet may not even use the same version of time that humans created to reach deadlines. The aliens may not even need telescopes to see earthly activities. If a quantum telescope were envisioned, things could be seen as they happen or, it could take them twice as long to see earthlings due to lesser than standard equipment and technology because they 'aren't' technologically advanced enough

Considering that Humankind has had a mere 2,000 years to develop anything like technology, we are at a dangerous stage in our development between the discovery and manipulation of atomic energy and our extinction. I it is my contention that we became visible to extraterrestrials with the first atomic weapons tests (assuming that they exist) and they have arrived to observe us and study our behavior. Given the obvious fact that we are creatures predisposed to violent action, they cannot risk contact. There are mounting highly credible reports of the presence of non-human beings here since the birth of the Atomic Era It seems obvious that they are watching us. Credible testimony from those who have directly witnessed the presence of non-human”visitors” at military bases, atomic missile sites and space launch facilities (Vandenberg for example) exist. I ask you to watch the new documentary featuring these eyewitness accounts entitled “The Age of Disclosure”. It is difficult to dismiss.

(I have no connection to the film nor its creators or distributors)

Seems to me that anybody observing us from light years away would need a BIG technological jump from where we are. Might be possible! Might not. I assume life is everywhere in the universe. Complex life that is interesting to normal people (sorry micro-biologists!) much less common. Intelligent life that might want to visit here? I can't even guess.

One branch of mammals here got smart enough to wonder about things like this. Might be a fluke. Look at crocodilians or sharks. They have been pretty much the same for many hundreds of millions of years. Not very smart. Because they were already perfect! Evolution responding to circumstances in their environment might make them bigger or smaller, or change the exact shape of their beaks, but they are still fundamentally the same. Not getting smarter.

We got smarter accidentally. Evolution does not select for intelligence, but for survivability. I expect there are, or have been, or will be, other critters with our penchant for exploring just because there are so damned many places they could be! But they would need tech that we have no dreams of yet to find us and visit.

Give us a few thousand more years and we might find a way to do it. But we have called our continued existence into question with just the few thousand years of tech we have now. Will we have the time?

Hope so.

Ok. But I'm more curious about the detectable range of our radio and TV broadcasts that might have leaked into space. How large and sensitive would an antenna/dish have to be to pick those up at, say... 10 light years?

The probability is very high that there are no aliens within detection range of Earth Our radio and TV broadcasts would be detectable only out to about 50 light-years from Earth, unless the aliens were directly in the path of military-grade radars or the Arecibo dish when it was transmitting. According to the Drake equation, even under the most optimistic of assumptions, you get a probability of 10-50% that there would be one advanced alien civilization within that volume of space. Less optimistic assumptions cut the probability almost to zero.