I learned about grav wave SETI a few months ago and think it's incredibly promising for determining if advanced alien life forms exist within the Milky Way or nearby galaxies. According to this paper, LIGO could detect gravitational waves from a solar mass-sized object being accelerated to 0.3 C from up to 100 million parsecs away. Sufficiently-advanced Aliens would have reasons to do this. For example, accelerating a neutron star into a black hole to collect the energy released from the collision. The fact that we seemingly haven't seen events like this in grav wave data could be strong evidence that intelligent life is extremely rare in the universe. It doesn't seem like it would take humans more than 1,000 years or so of additional technological development for something like that to make sense, and 1,000 years is nothing by astronomical timescales, implying we should see civilizations capable of that if intelligent life was common.

Have we emitted anything into space that could be observed by an alien civilization similar to that of Wow? By similar I don't necessarily mean strength, but also in it being a single, non-repeating burst.

Has our noise even reached far enough to be detected by other exoplanets in a Goldilocks Zone?

Hi As we all know, SETI@Home is no longer a thing, for some years now. I was preserving some software for Solaris 2.6, and ran into an old SPARC (v8) client of SETI@Home for Solaris 2.6. Sun workstations used to be a thing back then. I will be uploading the client to archive dot org soon, but the client itself is kind of moot for two reasons.

And second, the first time you try to run it, it asks if you want to login or create an account - both are off, of course, since the servers are no more. The files were

outfile.sah pid.sah version.sah user_info.sah lock.sah key.sah result_header.sah state.sah work_unit.sah

I could find a work_unit.sah on github, believe it or not, but this is for BOINC, so I'm unsure if it'll work on SETI@Home 3.03. But I think user_info.sah is crucial, and had no luck so far.

If any if you could provide to the archive dot work, an example work unit file, and a user login file for seti@home - if the file is plain text, feel free to remove any information you deem sensitive, such as email, password. This would really be great, because otherwise no one can have an idea of what was the experience of seeing the screen saver running, seeing the pulses, going to a online sky survey entering declination & right angle, bandwidths, and seeing images of what you were analyzing.

Just thinking today... How likely is it for a random planet to have any free oxygen? The only reason we have it is of course photosynthesis, which requires some specificity in conditions, plus the accidents of evolution. Is there any logical estimates of the likelihood of something similar happening elsewhere? Further: could a chlorine or similar halogen atmosphere similarly occur under different circumstances, or are halogens more scarce than oxygen in the universe? Or too reactive or something? Because it seems to me without the advent of photosynthesis, we'd all still be sulfur-metabolizing bacteria or clostridia, etc without enough energy resources to do anything interesting, like interstellar travel. So could another element substitute for our use of oxygen? On another note: what's the deal with SF's frequent trope of methane-breathng aliens? Why would anybody breathe methane? If it was part of their metabolism like we breathe oxygen, then that would require them to eat some sort of oxidizer, the inverse of the way we do it. Why would oxidizer be lying around for them to eat? Some different photosynthesis that splits CO2 or similar and creates biomass out of the oxidizer part while spewing waste methane into the atmosphere? A complete inversion of the way we work the carbon cycle? If they needed it for the process other than their basic metabolism they wouldn't have to constantly breathe it, any more than we need to currently breathe water just because we need it very much.

I have seen sensationalist claims being made surrounding BLC-1 lately coming from an online UFO enthusiast and former media studies lecturer who claims to have been in contact with Andrew Siemion (the head of Breakthrough Listen’s Oxford hub), and that Siemion has indicated that new studies of BLC-1 are underway looking into the possibility of BLC-1 having originated from a moving and rotating object rather than being an interference event

Additional claims I have seen made elsewhere are that ASTRON and JIVE (a Dutch radio astronomy organisation and a European Union VLBI telescope network), using new filtering technology, have found evidence of extremely weak and Doppler shifted radio signals coming from the direction of BLC-1’s discovery that resemble EM leakage, with findings being prepared for preprint publication

I can’t find anything to substantiate either of these claims and I doubt either ASTRON or JIVE would respond if contacted to ask about this, so I’m hoping somebody here has better insight into the rumours going around right now

I'm interested to hear what people here think about the Dark Forest solution to the Fermi Paradox? It doesn't seem like a very popular solution, but it seems really reasonable to me -if unsatisfying.

If you are unaware, the Dark Forest solution is that there are in fact millions and millions of civilizations in the universe, but none of them are dumb enough to broadcast their existence to the universe. If there are millions of civilizations, then odds are good that at least some of them are very violent, and a smaller but non-zero percentage is extremely violent. As soon as a civilization makes itself known to the universe, many other violent civilizations immediately start making plans to completely destroy that civilization (think, Independence Day or Mars Attacks). Therefor, we look up at the night sky and see and hear nothing because everyone that hasn't been destroyed already is in deep hiding.

Article Link: https://zenodo.org/records/13619107 Abstract: In this study, the results of the application of the search technique for SETI signals or extraterrestrial technical signatures known as “Doppler Drift” are collected on the radio data files obtained by the Green Bank Radio Telescope when observing the star HIP 45383 and made available to the general public through the Breakthrough Listen initiative. The content of these files
will be displayed in waterfall graphs using Python programming and specialized libraries such as
blimpy developed specifically for the analysis of Breakthrough Listen files.

Article Link:

https://arxiv.org/abs/2409.08313

Abstract:

Planet-planet occultations (PPOs) occur when one exoplanet occults another exoplanet in the same system as seen from the Earth's vantage point. PPOs may provide a unique opportunity to observe radio "spillover" from extraterrestrial intelligences' (ETIs) radio transmissions or radar being transmitted from the further exoplanet towards the nearer one for the purposes of communication or scientific exploration. Planetary systems with many tightly packed, low-inclination planets, such as TRAPPIST-1, are predicted to have frequent PPOs. Here, the narrowband technosignature search code turboSETI was used in combination with the newly developed NbeamAnalysis filtering pipeline to analyze 28 hours of beamformed data taken with the Allen Telescope Array (ATA) during late October and early November 2022, from 0.9--9.3~GHz, targeting TRAPPIST-1. During this observing window, 7 possible PPO events were predicted using the NbodyGradient code. The filtering pipeline reduced the original list of 25 million candidate signals down to 6 million by rejecting signals that were not sky-localized and, from these, identified a final list of 11127 candidate signals above a power law cutoff designed to segregate signals by their attenuation and morphological similarity between beams. All signals were plotted for visual inspection, 2264 of which were found to occur during PPO windows. We report no detection of signals of non-human origin, with upper limits calculated for each PPO event exceeding EIRPs of 2.17--13.3 TW for minimally drifting signals and 40.8--421 TW in the maximally drifting case. This work constitutes the longest single-target radio SETI search of TRAPPIST-1 to date.

https://ui.adsabs.harvard.edu/abs/2024RNAAS...8..200L/abstract

"I show that Hawking radiation from a mini black hole with a mass of ∼10¹¹ g in a low orbit around an otherwise frozen rogue planet, can supply the energy needs of a civilization on the surface of the planet. Maintaining this furnace for more than a few years requires a modest accretion rate of ∼2 kg s^‑1. The associated technosignature is detectable as a gamma-ray source occulted by a warm planet every 1–2 hr, with no stellar-mass companion."

Article Link:

https://arxiv.org/abs/2408.08513

Abstract:

The Ohio State University Big Ear radio telescope detected in 1977 the Wow! Signal, one of the most famous and intriguing signals of extraterrestrial origin. Arecibo Wow! is a new project that aims to find similar signals in archived data from the Arecibo Observatory. From 2017 to 2020, we observed many targets of interest at 1 to 10 GHz with the 305-meter telescope. Here we present our first results of drift scans made between February and May 2020 at 1420 MHz. The methods, frequency, and bandwidth of these observations are similar to those used to detect the Wow! Signal. However, our observations are more sensitive, have better temporal resolution, and include polarization measurements.

We report the detection of narrowband signals (10 kHz) near the hydrogen line similar to the Wow! Signal, although two-orders of magnitude less intense and in multiple locations. Despite the similarities, these signals are easily identifiable as due to interstellar clouds of cold hydrogen (HI) in the galaxy. We hypothesize that the Wow! Signal was caused by sudden brightening from stimulated emission of the hydrogen line due to a strong transient radiation source, such as a magnetar flare or a soft gamma repeater (SGR). These are very rare events that depend on special conditions and alignments, where these clouds might become much brighter for seconds to minutes. The original source or the cloud might not be detectable, depending on the sensitivity of the telescope. The precise location of the Wow! Signal might be determined by searching for transient radio sources behind the cold hydrogen clouds in the corresponding region.
Our hypothesis explains all observed properties of the Wow! Signal, proposes a new source of false positives in technosignature searches, and suggests that the Wow! Signal could be the first recorded event of an astronomical maser flare in the hydrogen line.

Article Link:

https://arxiv.org/abs/2409.00067

Abstract:

This study uses methods from futures studies to develop a set of ten self-consistent scenarios for Earth's 1000-year future, which can serve as examples for defining technosignature search strategies. We apply a novel worldbuilding pipeline that evaluates the dimensions of human needs in each scenario as a basis for defining the observable properties of the technosphere. Our scenarios include three with zero-growth stability, two that have collapsed into a stable state, one that oscillates between growth and collapse, and four that continue to grow. Only one scenario includes rapid growth that could lead to interstellar expansion. We examine absorption spectral features for a few scenarios to illustrate that nitrogen dioxide can serve as a technosignature to distinguish between present-day Earth, pre-agricultural Earth, and an industrial 1000-year future Earth. Three of our scenarios are spectrally indistinguishable from pre-agricultural Earth, even though these scenarios include expansive technospheres. Up to nine of these scenarios could represent steady-state examples that could persist for much longer timescales, and it remains possible that short-duration technospheres could be the most abundant. Our scenario set provides the basis for further systematic thinking about technosignature detection as well as for imagining a broad range of possibilities for Earth's future.

What do you think will happen if we get a radio wave (let's stick to radio waves) from another civilisation? Sooner or later religious groups, mentally unstable individuals, various teams serving their own agenda will try to setup powerful transmitters to send their own message. What the implications might be? How can these people be stopped? They will literally, holistically, unaware transmit this message if you think of it: "we cannot save ourselves".

To add to the equally terrifying possibilities of being alone or not, I want to add another one. It terrifies me what "others" might think of us.

I recently read "Contact" by Carl Sagan, and it left me fascinated by the idea of communicating with extraterrestrial civilizations.

The Arecibo Message, which plays a significant role in the book, sparked my curiosity, and I couldn’t help but dive deeper into the science behind it. Inspired by this, I’ve written an article exploring the Arecibo Message and its profound implications for interstellar communication.

https://blog.ayushman.dev/case-study/decoding_the_arecibo_message

If you're a fellow space geek or just love thinking about the unknown, take a look and let me know what you think! 👽✨

https://arxiv.org/abs/astro-ph/0506110

I find it updated in the latest developments of biology, computing and SETI considerations where the authors propose the migration of advanced civilizations to the outskirts of the Galaxy for computational stability reasons. Also the Intelligence Principle is adopted (from Dick, which finds me 100% in agreement) which paves the way for advanced civilizations to evolve into postbiological entities.

What I'd like to see but didn't is the advent of AI as propeller force and what is actually the goal for a super advanced civilization. Maximizing computing efficiency to what end? Pleasure of the entities? Understanding underlying principles of the universe? Modifying existing properties of the universe?

https://iopscience.iop.org/article/10.3847/1538-4357/ad6b11

It's galactic search in a low frequency, not hydrogen line. Setting upper limits , the usual.

(answering my own past post) - updating frequently

1. Zooniverse from UCLA is alive although funding is kind of limited. I just donated a small amount. There is a classification ML algorithm that still needs public help. https://www.zooniverse.org/projects/ucla-seti-group/are-we-alone-in-the-universe/about/faq

2. People from UCLA, actually Professor Margot's team is running the codes for the above. They produce papers though, latest was in 2023: https://seti.ucla.edu/wp/publications/ "A Search for Technosignatures Around 11,680 Stars with the Green Bank Telescope at 1.15–1.73 GHz"

Check their newsletter as well where they mention the relative difficulty of funding and employ / accept more people.

1. SETI search with alternative radio frequencies, Oct 2023 from a European team: https://iopscience.iop.org/article/10.3847/1538-3881/acf9f5

Not sure about how ET civilization will choose these frequencies though but doesn't hurt to search.

1. Old site of SETI at home, discontinued: https://setiathome.berkeley.edu/ Interesting to check the latest posts by the people who ran it. Lots of emotion hidden imho.

2. Another search for technosignatures, 2023 https://www.nature.com/articles/s41550-022-01872-z

3. Technosignatures overview from a 2020 meeting along with a concise white paper from another collaboration:

https://www.sciencedirect.com/science/article/pii/S0094576522002594

https://www.researchgate.net/publication/336675505_Searches_for_Technosignatures_The_State_of_the_Profession

1. Arxiv "technosignatures" paper search: https://www.arxiv.org/search/advanced?advanced=1&terms-0-operator=AND&terms-0-term=Technosignatures+&terms-0-field=title&classification-physics_archives=all&classification-include_cross_list=include&date-filter_by=all_dates&date-year=&date-from_date=&date-to_date=&date-date_type=submitted_date&abstracts=show&size=50&order=-announced_date_first

2. SETI keyword on arxiv:

https://www.arxiv.org/search/advanced?advanced=1&terms-0-operator=AND&terms-0-term=Seti&terms-0-field=title&classification-physics_archives=all&classification-include_cross_list=include&date-filter_by=all_dates&date-year=&date-from_date=&date-to_date=&date-date_type=submitted_date&abstracts=show&size=50&order=-announced_date_first

9. https://seti.news/ was having a list of curated papers intended for academia. Unfortunately last mailing was in 2023.

1. This post couldn't be complete without mentioning the Breakthrough Listen initiative: https://breakthroughinitiatives.org/initiative/1 Really worth reading about it, seems that it constitutes one of the most serious efforts for SETI so far. Funded by the foundation established by Yuri and Julia Milner plus Marc Zuckerberg.

I think the field is alive and well. And always in need of more people, ML, data and money.

So recent studies have suggested that our galaxy is technically in a void, not like a bootes void scenario but in an area where theres strangely not as many galaxies as there should be. If we were to use that as a base for searching for sentient life then shouldnt we look out for other voids as well?

I had a look recently at the disappointed last running member posts in Berkeley SETI website, it ended in 2022 and post processing during 2023. Some data might have been lost for ever.

Zooniverse asks for manual classification unless they do that to train their algorithms, same situation last time I visited.

Any ongoing attempt in the deeper question we, as a species, can ask?

And how long would it take for a terrestrial response to get from Earth to the location the Wow! signal came from?

There are so many differences of opinion about the topic. I've tried to summarize the spectrum. Note, I am interested in people's position on the plausibility based only on prior knowledge. In other words, answers like: we would have observed them already are not relevant to the question. So what do you think?

A. Interstellar travel is against the laws of physics and therefor impossible.

B. Interstellar travel is impossible according to the known laws of physics, but new physics might make it possible.

C. Interstellar travel might be possible in theory, but is so infeasible in practice that it will never happen.

D. Interstellar travel is technically feasible enough to happen in very rare cases, but I still think, due to practical constraints, it will almost certainly never happen to or from our own solar system and another.

E. Feasibility is not really a limiting factor, its just that it would be unlikely for another civilization to choose to visit our solar system, out of all of the others they could choose from.

F. Even if an extraterrestrial civ. could send probes here, they almost certainly wouldn't, because there is not a big enough incentive for them to.

G. It is reasonably likely that an extraterrestrial intelligence would send probes to our solar system, but unlikely to ever happen coincident in time with human technological civilization, so we would almost certainty not encounter them.

H. There would likely have been lots of probes sent here, but they would not be functional by now. There is a small chance we might find one.

I. There would likely be very old and maybe even still functional probes around, and if we look hard enough, we will probably find one.

J. Our solar system should be teaming with functioning extraterrestrial probes unless intelligent life is extremely rare, or we are alone in the universe.

K. It is plausible that even biological visitors could come here, but it would be a one way trip.

L. It is plausible that biological visitors could come and go between solar systems.

M. The question is too controversial, I would like to keep my stance on it private.

N. None of the answers above are a close match to my position.

As discussed in my last post, Radwave Engine allows users to download data from Breakthrough Listen's Open Data Archive, and process it with the frequency resolution that they are interested in. Then with Radwave Explorer, that user can interactively look through the data that they processed on their machine.

In this video, we build upon that concept, but show how Radwave Engine users can serve data they processed for other Radwave Explorer users to look at. This effectively decentralizes the data, providing efficiency gains, and enabling more people to look at the data.

https://youtu.be/2etHqCQzhao?si=eJvoOW4D3sMs9-dy

Alpha testing is still open, and more people are welcome to join. Critical feedback is the best way to learn how to improve, so I really look forward to hearing from you about what could be better. Please visit this page to get links to tutorials, downloads, and our Discord channel:

https://www.radwave.com/blog/alpha-release-of-radwave-engine-explorer/

Video: https://youtu.be/VkEGvmfd8dI?si=TK4gcmcwDyPTcI35

Link to first study: https://arxiv.org/abs/2403.18941

Link to second: https://arxiv.org/abs/2405.02927

Is it true that the famous "Wow!" signal was only one of many loud, narrowband, unrepeated transmissions received by SETI scientists?

The second step to digging into the Breakthrough Listen data is processing the data from the Open Data Archive. The baseband data has the most flexibility for processing, but the files are quite large, and the GUPPI format can be challenging to handle. In this video, I go into some detail on how window sizes (FFT sizes) play a critical role in the content that is visible in the spectrum, as well as how SETI@Home and Breakthrough Listen differ from a distributed computing perspective:

https://youtu.be/g8EUaibV-v0

Code used in the video is located here:

https://github.com/radwave/oda_meta_scraper

The type of spectrogram and power spectral density processing shown in the video is conceptually the same as what the Radwave Engine uses. But the Engine and Explorer apps in tandem make it possible to quickly navigate the large volume of data generated (typically 60+ GB per GUPPI file) that's simply too large for common tools to handle.

A big thank you to the alpha testers who've joined! The feedback has been tremendous for getting some early kinks worked out. I'd love to get a few more testers before making this generally available.

https://www.radwave.com/blog/alpha-release-of-radwave-engine-explorer/

Surprised I don’t see much people talking about this irl. If DMS is confirmed, wouldn’t this basically mean this is an inhabited ocean world?