25 Comments

1. Alex Tolley on January 10, 2019 at 11:19

   Archivists and curators never lose usefulness.

2. Michael Spencer on January 10, 2019 at 13:26

   Our debt to Dr. Tarter ratchets up, once again, already beyond retiring. Standing firm in the face of often derisive criticism, she has almost singlehandedly lifted SETI to respectable – and respected – heights. Decade after decade she has demonstrated what it means to be a true believer. And a serious scientist.

   Indeed as a popularizer she has no peer (the tireless Seth Shostack standing at her side). Her analogy – that to date, SETI research matches a teaspoon taken from Earth’s oceans – is so vivid, repeated by me and countless others to the doubters, and wonderers, over the decades.

   We can never repay her. May she never stop

   • Andrei on January 14, 2019 at 16:39

     I fully agree Mr Spencer, she have done very important contributions, and advocated the search – while being confused/ derided for looking for ‘little green men’.
     Even as I disagree with most SETI scientists about the chance to find another civilization, it’s their job to be optimistic.
     We do agree that the search should continue, if there’s a ‘great filter’ that make civilizations disappear – we still have learned something, and need to take action. Or if intelligence is very rare, we still need to better care of ourselves and our planet.
     To me, both results would be an equally important finding.

3. Jason Wright on January 10, 2019 at 14:09

   Notes:
   1) I’m at Penn State
   2) The collaboration was actually with students of my class, Will Bowman and Caleb Cañas, not with me directly:
   https://sites.psu.edu/seticourse/final-projects/observational-seti-programs-through-the-decades/

   • Paul Gilster on January 10, 2019 at 14:13

     Yipes! What a typo. Have just fixed it.

4. Daniel Suggs on January 10, 2019 at 15:28

   I enjoyed your input to the Space dot com article on a possible interstellar probe. Well done.

   • Paul Gilster on January 10, 2019 at 15:33

     Thanks, Daniel. It’s always good to talk to Leonard David, who did his usual excellent job on that article.

5. Laintal on January 10, 2019 at 16:04

   A very good update Paul

   It was amazing to attend one of Jill’s talks

6. Gary Wilson on January 10, 2019 at 18:12

   Thanks to Jill Tarter and the students of Jason Wright. A brilliant idea.

7. Robin Datta on January 10, 2019 at 20:48

   “When the student is ready, the teacher appears”, the saying goes in some Eastern traditions. Let’s hope that that is also applicable to SETI as well: when the observer is ready, the evidence appears.

8. Dmitry Novoseltsev on January 10, 2019 at 23:46

   In addition to proposed database, I would suggest a separate section that includes data on the possible chemical and biochemical technosignatures, detectable in spectrometric and other observations.
   A number of papers (Adam Stevens, Duncan Forgan and Jack O’Malley. Signatures of Self¬-Destructive Civilisations. International Journal of Astrobiology 07/2015; -1(4)) have already considered some options.
   Thus, I suppose that the areas of increased concentration of complex organic compounds, up to DNA, RNA and their fragments, in protoplanetary disks of young stable stars, especially localized in certain areas of protoplanetary disks (Dmitry Novoseltsev. Engineering New Worlds: Creating the Future. Principium. Issue 17, May 2017), can be considered as potential technosignatures. This can be interpreted as the result of targeted activities for the dissemination of biological life, the most adapted to local conditions (analogue of the project “Catalysis”, the first stage). The results of recent experiments on the synthesis of complex sugars (Michel Nuevo, George Cooper, Scott A. Sandford. Deoxyribose and deoxysugar derivatives from photoprocessed astrophysical ice analogues and comparison to meteorites. Nature communications (2018) 9:5276.) generally confirm the technical feasibility of such a project.
   Another option may be an analogue of the project “Genesis” (Claudius Gros. Developing ecospheres on transiently habitable planets: the genesis project. Astrophys Space Sci (2016) 361:324), which may be manifested in observations as the detection of complex groups of biomarkers, presumably characteristic of the developed biosphere, in the atmospheres of fairly young exoplanets.

9. Michael C. Fidler on January 11, 2019 at 9:42

   Good article on Barnard’s star b at GeekWire but the best part is the link to the poster presentation from the AAS 23 meeting.

   https://www.geekwire.com/2019/barnards-star-harbor-icy-home-life-astronomers-weigh-options/

   http://clusty.ast.villanova.edu/gallery/Barnard_Poster_AAS2019.pdf

   Now bear with me for there may be a relation to Technosignatures.
   If life did develop on a planet like b in the early higher intensity youth of Barnard’s star what interest me is the comparison to our snowball earth. If geothermal activity may of helped complex life develop around hotspots in the snowball earth could it already have advanced enough that the cambrian explosion was not an explosion but an outcome of those pockets of life. Since the ice destroyed all fossil evidence in that period we do not know what happened. “Researchers suggest missing crust layer can be blamed on ‘Snowball Earth.’ ” https://phys.org/news/2019-01-crust-layer-blamed-snowball-earth.html
   Neoproterozoic glacial origin of the Great Unconformity.
   https://www.pnas.org/content/early/2019/01/07/1804350116

   So life may have developed on Barnard’s star b and Proxima b dark side, so these two nearby planets and stars should be observed carefully at all frequencies for signs of technosignatures and the other possibility of other ET’s colonizing them. This is where we can look at the type of devices or structures that may exist and also look for unusual signatures that may not have been considered in the normal SETI. Barnard’s star is an especially good target because it is only 4 degrees north and can be observed from all places on earth. A program of permanent observations 24 hours a day with smaller instruments could be justified.

10. AlexT on January 12, 2019 at 4:34

    I suppose that good database that dedicated to SETI efforts and results, add the good ground for “Fermi paradox” and “negative SETI results “. Scientists need only to decide when to stop and there was well enough SETI to conclude that present (seti) methodology gave only negative results… and this “negative” – it is real scientific fact that have to be scientifically explained and further research methodology have to be coordinally changed.

    • Andrei on January 15, 2019 at 6:49

      We are very far from that yet.
      Current instruments can only detect general radio noise up to a few hundred lightyears. Dedicated transmissions up to about ten thousand lightyears – unless the civilization have an incredibly powerful transmitter. But we do not monitor all the sky at all times either, a species who send a blip every few thousand years to all stars that is promising, calling for our attention – with a general broadcast that need a much more sensitive radio telescope to be received – easily could have been missed.
      A likely scenario is that once we have the instruments to really scan the sky efficiently, we pick up a signal from a civilization that broadcasted long ago, and who no longer exist.
      There were an interesting paper published about that some years ago, I do not remember the title, but now with Dr Tarter’s database I guess I can find it again. :)

      • AlexT on January 16, 2019 at 5:10

        It was retiric question – I am sure that SETI activists will never conclude that their efforts brought negative results. It only proves my statement that SETI’s fan argument that “negative SETI result is also good scientific result” – is hoax, no more, because it will be always possible to use contr-arguments like you use :-) Universe in huge – it is fact.
        But I mean that there should be some limit, when scientific community that methods used by SETI are wrong, it is mostly gambling than making science and all further SETI activity should be left for professional gamblers, i.e. private funding only, no any government funds allowed anymore.
        In addition I am in doubt that SETI science, because it leave no posdibility and chance to get negative result. Negative redult in SETI is same operation like divide number by ZERO.
        In same time – discussed database creation – is good deeds, because it solidifying fruiltess “success” of SETI efforts.

        • Andrei on January 16, 2019 at 11:33

          Yes I guessed it was.
          But you pointed at a thinking I have noted, and that is:
          We have not found anything when listening to radio signals so far – so perhaps we need to look for other wavelengths, laser, exotic massive and- or high energy particles etc.
          So my reply were also rhetoric, radio make sense for a first contact ‘hello’ and that we have not even started to look yet – as the sensitivity and around the clock monitoring of at least a large part of the sky is not currently done.
          Radio telescopes have a wide field, so such a system is possible, also the technology to shift trough million of frequencies in a short time, what is missing is the sensitivity.
          To make an equally good system for some exotic way of communication, might be more expensive and take an even larger effort. So aliens, if they broadcast right now, will know that also.
          So far we agree, but I am against the idea of privately funded science in any form, as such do not only demand results, but also ask for control over how the research is carried out, and there will not be the same double check with peer review etc as in academia.
          This is a long term project, and also blue sky research – such never have done well in the hands of private funders.

          • AlexT on January 16, 2019 at 16:38

            …exotic way of communication..

            I am sure any communication that is limited by speed of light on the distances more than ~50 light years is practically impossible, too slow exchange rate.

            …I am against the idea of privately funded science in any form…

            After some close look at SETI history and modern SETI community, I am sure now – SETI is not the science, may be on some higher levels it is good engineering hobby and science fiction dreams. SETI’s methods – are mostly gambling.
            Widely advertised outcomes of SETI positive result – many order overestimated, if positive SETI efforts can give as only answer to one scientific question – “we are not alone”, but in same case SETI methodology do not allows negative result in any way.
            So in the case we are alone (or we are fist intelligent life in he Universe) – SETI approach does not allow to confirm this fact, analyzing modern sources I see no way , how SETI can do that.
            So I am sure it will be better to spend SETI funds to real science and engineering (astronomy, space exploration and colonization, biology, novel propulsion engines etc.).
            SETI it is branch of HAM radio hobby, with difference that it does not allow duplex communication in reasonable time scale :-)

11. Michelangelo on January 15, 2019 at 12:41

    Is there any database similar to this but for METI? It would be interesting to know the power and frequency range of each radio message sent to space (with a minimal power threshold just to avoid considering each TV transmission a METI message).

    In that way we could map the number of stars that could receive those messages with a fixed size for the receiver antenna and establish which time is more probable to receive a response considering two-way paths.

    • ljk on January 16, 2019 at 12:06

      That is an excellent idea. Know anyone who can handle this? The SETI Institute, if they are not afraid to touch the subject? Breakthrough Listen, where METI is supposed to be one of their objectives?

      Here is a start:

      https://en.wikipedia.org/wiki/Active_SETI

    • ljk on January 16, 2019 at 12:25

      Note that METI can also be physical, not just electromagnetic transmissions:

      Keeping Track of the Weird Stuff We Send Into Space?

      A new catalogue attempts to figure out what we’re telling the rest of the universe about ourselves.

      by Sarah Laskow

      November 19, 2018

      https://www.atlasobscura.com/articles/weird-stuff-sent-to-space

12. ljk on January 17, 2019 at 11:34

    https://arxiv.org/abs/1901.04057

    A search for technosignatures from TRAPPIST-1, LHS 1140, and 10 planetary systems in the Kepler field with the Green Bank Telescope at 1.15-1.73 GHz

    Pavlo Pinchuk, Jean-Luc Margot, Adam H. Greenberg, Thomas Ayalde, Chad Bloxham, Arjun Boddu, Luis Gerardo Chinchilla-Garcia, Micah Cliffe, Sara Gallagher, Kira Hart, Brayden Hesford, Inbal Mizrahi, Ruth Pike, Dominic Rodger, Bade Sayki, Una Schneck, Aysen Tan, Yinxue “Yolanda” Xiao, Ryan S. Lynch

    (Submitted on 13 Jan 2019)

    As part of our ongoing search for technosignatures, we collected over three terabytes of data in May 2017 with the L-band receiver (1.15-1.73 GHz) of the 100 m diameter Green Bank Telescope. These observations focused primarily on planetary systems in the Kepler field, but also included scans of the recently discovered TRAPPIST-1 and LHS 1140 systems.

    We present the results of our search for narrowband signals in this data set with techniques that are generally similar to those described by Margot et al. (2018). Our improved data processing pipeline classified over 98% of the ? 6 million detected signals as anthropogenic Radio Frequency Interference (RFI). Of the remaining candidates, 30 were detected outside of densely populated frequency regions attributable to RFI. These candidates were carefully examined and determined to be of terrestrial origin.

    We discuss the problems associated with the common practice of ignoring frequency space around candidate detections in radio technosignature detection pipelines. These problems include inaccurate estimates of figures of merit and unreliable upper limits on the prevalence of technosignatures.

    We present an algorithm that mitigates these problems and improves the efficiency of the search. Specifically, our new algorithm increases the number of candidate detections by a factor of more than four compared to Margot et al. (2018).

    Comments: 17 pages, 9 figures

    Subjects: Earth and Planetary Astrophysics (astro-ph.EP); Instrumentation and Methods for Astrophysics (astro-ph.IM); Popular Physics (physics.pop-ph)

    Cite as: arXiv:1901.04057 [astro-ph.EP]
    (or arXiv:1901.04057v1 [astro-ph.EP] for this version)

    Submission history

    From: Pavlo Pinchuk [view email]

    [v1] Sun, 13 Jan 2019 20:38:23 UTC (2,367 KB)

    https://arxiv.org/pdf/1901.04057.pdf

13. ljk on January 17, 2019 at 11:58

    15th January 2019

    Parasitic SETI and Parasitic Space Science

    Recently there have been signs that NASA may consider a rapprochement with SETI and SETI scientists, after more than twenty years of a de facto NASA ban on funding SETI. It’s not yet clear how far this rapprochement will extend, but NASA did lend its name to the NASA Technosignatures Workshop (NTW18) last September. I wrote on Twitter that the term “technosignatures” may be more palatable than “SETI,” which may sound like an overly-subtle gloss on the situation, but it is still significant. It is conceivable that NASA will consider funding projects that mention “technosignatures” while continuing to pass over any project that mentions “SETI.”

    Full article here:

    http://geopolicraticus.tumblr.com/post/182049010987/parasitic-seti-and-parasitic-space-science

    To quote:

    There is a kind of subtle irony in SETI science having to operate parasitically on other projects deemed more fundable, or, at least, projects that would not draw the ire of politicians looking for a soft budgetary target to attack. Arguably, whatever public support that there is for space exploration (and however correct or mistaken it may be to connect space exploration with SETI), derives from the hope, perhaps even the titillating hope, of finding something “out there” that would mean that we are not alone.

    I have often said that the excitement over things like exoplanet searches always turns on whether the planets are habitable, and excitement over whether the planet is habitable largely turns on whether we can ever determine whether or not these planets have life, and the excitement over whether or not we can determine if these planets have life largely turns on whether that life could be intelligent, and the excitement over whether or not this life could be intelligent largely turns on whether we might possibly communicate with or travel to these intelligent beings.

    I’ve read a few candid comments to this effect (I can’t remember the source), and I have no doubt that this is the case. In the same way that conservation biology has an easier time raising money to fight for charismatic megafauna but has a much more difficult time raising money based on unattractive or very small animals, so too space science efforts do better when they are related to some “sexy” space science topic like aliens—but this has to be done sotto voce, with a wink and a nudge, because NASA, to be taken seriously, must keep up the appearances of a buttoned-down science prof.

    In a sense, then, it is space science that is parasitic upon SETI and human spaceflight (which appeals as a source of national pride in accomplishment), which, when the latter dominated NASA and NASA’s budget, took the lion’s share of the money and left little for space science. In recent decades, the focus has been more on space science, and so it is SETI (rather than prestige) which is the unspoken background to what is going on in the foreground.

    While I care deeply about space science, and I know how much NASA’s space science programs have transformed our knowledge of the universe, few in the public share my sentiments, and they cannot be expected to share them. But they can share an interest in the “charismatic megafauna” of astrobiology, which are the intelligent aliens that SETI is seeking.

    If NASA can embrace technosignatures as a part of astrobiology, it may find a way to excite the interest of the public while maintaining its scientific respectability. And if that requires a shift in terminology, I suspect that SETI researchers will be ready to make that shift. Of course, any scientific discipline, as it evolves, eventually revises its terminology, as it usually begins with imprecise terms from ordinary language and eventually settles upon more formalized usages that are defined with scientific precision. And there is scientific precision in spades to be found in SETI research papers. What is wanting in SETI (and in technosignatures, for that matter) is the conceptual framework within which these terms of formulated. SETI science is strong, but its concepts are often weak and ambiguous. I have had this on my mind for some time, and I hope to be able to write more about this as I clarify my own thoughts on the matter.

14. ljk on January 18, 2019 at 11:02

    17 January 2019

    AI helps us sift for SETI signals

    We’ve just released a new research paper on a deep learning alternative to traditional SETI algorithms.

    At Breakthrough Listen, we filter candidate signals by their localization on the sky. At the Green Bank Telescope (GBT), we conduct observations in an “on/off” fashion. The telescope focuses on a small region of the sky for 5 minutes, before moving “off-target” for 5 minutes. The majority of signals appear in both observations, indicating that they are not originating from the target direction, but rather from a terrestrial source nearby.

    Full article here:

    http://seti.berkeley.edu:8000/conv-lstm/

    The paper, published in the 2018 IEEE GlobalSIP conference, is available for download at:

    https://arxiv.org/pdf/1901.04636.pdf

15. ljk on January 18, 2019 at 11:32

    https://arxiv.org/abs/1901.04636

    Self-supervised Anomaly Detection for Narrowband SETI

    Yunfan Gerry Zhang, Ki Hyun Won, Seung Woo Son, Andrew Siemion, Steve Croft

    (Submitted on 15 Jan 2019)

    The Search for Extra-terrestrial Intelligence (SETI) aims to find technological signals of extra-solar origin. Radio frequency SETI is characterized by large unlabeled datasets and complex interference environment. The infinite possibilities of potential signal types require generalizable signal processing techniques with little human supervision.

    We present a generative model of self-supervised deep learning that can be used for anomaly detection and spatial filtering. We develop and evaluate our approach on spectrograms containing narrowband signals collected by Breakthrough Listen at the Green Bank telescope. The proposed approach is not meant to replace current narrowband searches but to demonstrate the potential to generalize to other signal types.

    Comments: 5 pages, 3 figures

    Subjects: Instrumentation and Methods for Astrophysics (astro-ph.IM)
    Journal reference: IEEE GlobalSIP 2018

    Cite as: arXiv:1901.04636 [astro-ph.IM]
    (or arXiv:1901.04636v1 [astro-ph.IM] for this version)

    Submission history

    From: Yunfan Zhang G. [view email]

    [v1] Tue, 15 Jan 2019 01:59:30 UTC (1,658 KB)

    https://arxiv.org/pdf/1901.04636.pdf

16. ljk on March 11, 2019 at 14:46

    Megastructures: A Sign of Larger than Life Aliens?

    https://interestingengineering.com/megastructures-a-sign-of-larger-than-life-aliens