Why haven't aliens got in contact with us yet?

[Ryujin]

(I'm doing this rather a lot, but....) I book I read, but again can't remember the title of, was based on the premise that a SETI installation detected a "Wow!" signal, that was composed of a high powered LASER transmission from a distant star. Clearly it was aimed at us. Clearly we had no way to know how they knew of our presence, because the star system in question was well outside our range of historic transmission (as in by millennia). It was a densely packed, three dimensional model transmission that included high physics concepts like the creation of wormholes, singularities, and the like. Information that could easily be used to destroy the Earth and more. One of the big questions in the story was why would they send all of that?

LASERs would be one way to send such data, that could be detected by our present day technology, and I believe it's one of the things that SETI is looking for. Single wavelength light isn't exactly a naturally occurring phenomenon.

 

[Umbran]

The gap created when the Dyson sphere was created (from the STNG episode).

1) Wasn't actually created by the culture of the Federation, or its allies/adversaries. If I recall correctly, that Sphere had been abandoned.

2) The Dyson Sphere is a stellar-sized object, but it only emits in the infrared. Technically that could be detected, but practically speaking - it is *one* star. One. Out of billions. It'd have to be close by to expect us to note it by anything other than chance.

Anomalous supernovas, of which there have been several.

You don't know it was anomalous unless you were watching the star *before* the supernova. So, again, except by sheer chance, you won't realize, "Wait, that star shouldn't have exploded at all!"

Shock waves of various sorts.

With respect, "shock waves" in the Trek sense are not a thing, despite what the treknobabble says. In reality, a shock wave is what you get when a wave is moving through a medium faster than the speed of sound in that medium. Note how in interstellar space, there is no medium to speak of, and you can't have a shock wave in a medium that doesn't exist. If your shock wave is in subspace, we won't see it.

 

[Umbran]

LASERs would be one way to send such data, that could be detected by our present day technology, and I believe it's one of the things that SETI is looking for. Single wavelength light isn't exactly a naturally occurring phenomenon.

SETI has optical detection projects, but they aren't anywhere near comprehensive - meaning that there's a lot of sky, and they don't watch all of it all the time. So, again, technically it *could* be detected, but in a practical sense, it likely wouldn't be.

 

[Ryujin]

With respect, "shock waves" in the Trek sense are not a thing, despite what the treknobabble says. In reality, a shock wave is what you get when a wave is moving through a medium faster than the speed of sound in that medium. Note how in interstellar space, there is no medium to speak of, and you can't have a shock wave in a medium that doesn't exist. If your shock wave is in subspace, we won't see it.

"Gravity waves"?

SETI has optical detection projects, but they aren't anywhere near comprehensive - meaning that there's a lot of sky, and they don't watch all of it all the time. So, again, technically it *could* be detected, but in a practical sense, it likely wouldn't be.

In the book the source was improbably bright and stood out from the background. Virtually "naked eye" bright; the sort of thing that would take a sizable amount of the output of a star to create the single, coherent beam.

 

[Eltab]

Not really. We mainly find gas giants because they're easy to spot. Small rocky planets like ours are harder to see. Therefore the vast majority of planets we've detected so far have been the ones we're currently capable of seeing.

Of course. Not what I was alluding to.
The gas giants we have found, their non-circular orbits, and distance from their star are leaving very few systems where an Earth-like planet can exist at the right range from its star.

Then there is the problem that yellow (and nearly-so) stars are not all that common to start with.

 

[Eltab]

We spend a lot of time being grimddark, future's gonna suck. It only sucks if we let it.

I was only a kid at the time, but I remember seeing grown adults cry when they heard that the Apollo Project was cancelled. Because somebody had just reached out and killed a Dream.

 

[Umbran]

"Gravity waves"?

Gravity waves exist, yes. But note that we only detected our first gravity waves *two months ago*. And that was an event that turned three times the mass of our sun directly into gravity waves in a fraction of a second, and we only barely detected it. The societies in the Trek universe aren't releasing energy on that magnitude. So again, we'd not detect Star Trek cultures via our current gravity detection tech.

 

[Ryujin]

Gravity waves exist, yes. But note that we only detected our first gravity waves *two months ago*. And that was an event that turned three times the mass of our sun directly into gravity waves in a fraction of a second, and we only barely detected it. The societies in the Trek universe aren't releasing energy on that magnitude. So again, we'd not detect Star Trek cultures via our current gravity detection tech.

You never know. We might be this galaxy's "hot girl" and some strapping young intergalactic culture might slap a couple of galactic core black holes together, to get our attention. After all, size does matter. Or anti-matter.

 

[tomBitonti]

1) Wasn't actually created by the culture of the Federation, or its allies/adversaries. If I recall correctly, that Sphere had been abandoned.

2) The Dyson Sphere is a stellar-sized object, but it only emits in the infrared. Technically that could be detected, but practically speaking - it is *one* star. One. Out of billions. It'd have to be close by to expect us to note it by anything other than chance.

You don't know it was anomalous unless you were watching the star *before* the supernova. So, again, except by sheer chance, you won't realize, "Wait, that star shouldn't have exploded at all!"

With respect, "shock waves" in the Trek sense are not a thing, despite what the treknobabble says. In reality, a shock wave is what you get when a wave is moving through a medium faster than the speed of sound in that medium. Note how in interstellar space, there is no medium to speak of, and you can't have a shock wave in a medium that doesn't exist. If your shock wave is in subspace, we won't see it.

Based on the star trek timeline, there seems to be an extra supernova about every 100 years, if not more often. That is already (about) 5-10x the number of supernovas per millenium for the milky way than the current observed rate. And that rate is just in a our quite small neighborhood. It seems that we might notice that the population of supernovas in our and other galaxies don't match up, or at least we would notice a particular type of supernova which is modeled as "anomalous main sequence supernova" with an unknown physical process causing fusion to stop. Or rather, those would be the dominant type, since there would be a lot more of them than natural supernovae.

Not clear from the episode itself, but there is a ST novel about the Dyson sphere which described a 100ly void around it which were the stars and such which were dismantled to create the sphere.

Anyways, Star Trek has had a number of Kardashey type II civilizations, which seem likely to have noticeable impacts.

Or maybe not. The impacts might not be noticeable for another few centuries, which for the ST universe is past when we achieved warp drive, so the point becomes moot. But if we stay near our current technology for the next 1000 years, I'm thinking that is enough time for us to notice things.

Thx!
Tom

 

[Morrus]

Gravity waves exist, yes. But note that we only detected our first gravity waves *two months ago*. And that was an event that turned three times the mass of our sun directly into gravity waves in a fraction of a second, and we only barely detected it. The societies in the Trek universe aren't releasing energy on that magnitude. So again, we'd not detect Star Trek cultures via our current gravity detection tech.

Societies might not, but random Romulans from the future and Vgers and Qs and stuff are all doing pretty wacky things.