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New Horizons: Surprise in Houston

There is much to say about the 100 Year Starship Symposium in Houston, and as I have done with prior conferences, I will be drawing on my notes in the coming weeks. But I want to start the Houston coverage with the good news that emerged from the outer Solar System. Some time back, Jon Lomberg came up with the idea of sending a new kind of message into deep space. No, this wasn’t to be a controversial signal beamed at a nearby star, but a message from humanity that would fly aboard one of our spacecraft. New Horizons is already in the outer system on its way to a Pluto/Charon encounter in 2015 and, we hope, a close pass of a Kuiper Belt object after that. But Jon thought we could still use it, Voyager style, to house the sights and sounds of Earth.

lomberg

The plan: To re-purpose a chunk of New Horizons’ computer memory, about 120 MB worth, after it has achieved its mission and is continuing out into interstellar space. The 120 MB figure is at this point a rough guess; it represents about 1 percent of the onboard memory. The message from humanity could be assembled by crowd-sourcing the project, getting input from all over the world, and uploading to the spacecraft — Lomberg’s idea is to begin a global contest allowing people to submit their ideas exactly one year before New Horizons flies by Pluto in July of 2015.

Image: Jon Lomberg, who is once again thinking about how to send the sights and sounds of Earth into the cosmos.

I was happy to join the advisory team for the project, for if there’s anyone who can make this happen, it’s Jon. He’s well known as an artist who worked with Carl Sagan on COSMOS and with Frank Drake in designing the cover for the Voyager Interstellar Record. Sending human artifacts on interstellar trajectories is not exactly a common thing to do, but Jon Lomberg is one of the few who has experience at it.

While conversations about the project went into into full gear on the Net earlier this summer, my son Miles went to work on the website that would eventually take the New Horizons Message public. I had assumed when I left for Houston and the 100 Year Starship that I would be focused solely on the various meetings and presentations there, but on Friday night Miles, who had been tuning up the site off and on during the conference, told me that it was ready to go. A quick confirmation with Jon gave the go-ahead to make the project public. Serendipity rules, for who better to make the announcement than the guiding force of SETI, Jill Tarter, who was herself on Jon’s advisory panel, and who even as we were discussing this happened to walk right by?

IMG_0174

Image: A lively Friday night in Houston. From left, former Planetary Society executive director Louis Friedman, my son Miles, Jill Tarter and TZF founder Marc Millis.

Thus Friday night, which had already been enlivened by a panel with writers Jack McDevitt, Ken Scholes, Karin Lowachee and Mary Doria Russell, became an impromptu planning moment in the crowded foyer outside the ballroom. Jill quickly agreed, Miles forwarded the relevant URL to her computer, and the next morning, after guiding an excellent panel on recent discoveries (about which more later this week), Jill announced the New Horizons Message Initiative and put the site up on the screen. We then asked the formidable LeVar Burton, also intercepted in the foyer, to blast out a tweet to his 1.7 million followers on Twitter, and the initiative was launched.

IMG_0177

Image: A quick chat with LeVar Burton. Talk about a fun guy to be around, LeVar is a strong advocate for pushing to the stars, and he signed off on the New Horizons Message without hesitation.

There is much to do. First of all, we need people to go to the site to sign the petition to demonstrate public support that will persuade NASA. The New Horizons Message is a private initiative, and thousands of signatures on the online petition along with endorsements from leaders in astronomy and space sciences will be crucial in making the case to NASA. Also ahead is a fundraising campaign to provide the necessary budget supporting the project, which will pay for developing the techniques for storing and sending the message, holding meetings and conferences to plan and manage the submission process, and formulating and executing the ensuing contest.

The key here is to make this a message from the entire world, searching globally for pictures and other materials that can be voted upon in various categories of content. A self portrait of Earth in the early 21st Century will thus emerge. Unlike the Voyager Golden Record or the Pioneer plaques, however, this is a record that, once uploaded, can be updated over time, as long as the spacecraft is still in communication with the Earth.

No one realistically sees the New Horizons Message as a way to reach ET. This initiative is really about the Earth, and you might think back to the days of Apollo 8 and the stunning Earthrise photograph that so changed our perspective on our own planet. Astronaut Eugene Cernan is famous for saying “We went to explore the Moon, and in fact discovered the Earth.” That sentence was printed on a large poster in the ballroom at the 100 Year Starship Symposium, and along with it a parallel one: “What will we discover from another star?”

It’s a question with profound implications. I’ve said before in these pages that while the problem of the starship is a problem of science, it is also a problem of philosophy, for we have key choices to make as a species on how we want to live. Turning our aspirations toward space offers us the opportunity to reflect on our place in the cosmos and to see what we are doing in a new light. I strongly support the New Horizons Message Initiative and hope you will as well.

nhmi

Comments on this entry are closed.

  • Antonio Tavani September 23, 2013, 10:29

    Bellissima iniziativa!
    Ma fino a quando, questa missione spaziale, sarà in contatto radio, con il nostro pianeta?
    Saluti da Antonio Tavani

    Via Google Translate:

    Wonderful initiative!
    But how long will this space mission be in radio contact with our planet?

    Greetings from Antonio Tavani

  • Alex Tolley September 23, 2013, 12:04

    My first thought is that this project will have to face not only the “dead file format” problem, but also the “dead chip hardware” problem.

    Proprietary/lost file formats are going to be a real problem. With only 120MB, the temptation is to used highly compressed file formats. Will we even know about them when the New Horizons is found/reactivated/retrieved? But even a simple uncompressed bitmap may prove difficult to decode (how many bits/pixel, is the file contiguous?). [The website is vague of the file format, but if it is new, that might further obfuscate the decoding].

    The hardware problem has already been faced with the project to recover the Apollo moon landing data, and that was less than 50 years ago. Our salvage crew must know that there is useful data in the memory (archived how, as not indicated on the spacecraft?), correctly identify the memory chips (Solid State Recorder = flashdrive?), and then, either in situ or removed, reactivate the chip and extract the information somehow. Will this require potentially reading transistor states? If this somewhat daunting prospect is correct, how much damage of the information is going to happen due to GCR impacts and other bit destroying processes? We might be able to do this, but how is ET going to know anything about the hardware and memory contents?

    I think the concept is lovely, but I doubt the practically of the project to achieve its message transmission goal. It may be hard enough for us to retrieve, let alone ET. We’ve discussed this idea of information storage for use on satellites to preserve our cultural information, with many of the same issues.

  • Paul Gilster September 23, 2013, 13:37

    Re Antonio’s question above, this from the New Horizons Message Initiative site:

    How long will the message last on the computer memory?
    Nobody really knows. The spacecraft memory is similar to a flash drive storage device, very different from anything on Voyager.
    The extreme cold might lengthen the time it takes the message to fade, the radiation environment might shorten it. The most conservative estimates are a lifetime of a few decades. Other physicists and engineers believe the message might remain for centuries or even millennia. Another unknown is the advanced technology ETs who find the spacecraft might possess. They might have ways of reading the faded memory we cannot yet imagine.

    As to how long we will be talking to New Horizons, I don’t know the answer to that one. Can anyone help?

  • Rafal September 23, 2013, 13:54

    off topic, but very important. We’re 3 planets short or reaching 1000 known exoplanets.
    http://exoplanet.eu/catalog/

  • Andrew Palfreyman September 23, 2013, 14:31

    Hate to be a killjoy, but New Horizons is an absolute tortoise. We could beam something out there to pass it in short order at many times its speed. Oops – except we don’t have any beamers.

    The 2012 NASA Beamed-Energy Propulsion (BEP) Study slates space-based beamers as “economically unviable”. And they’re right – a market doesn’t exist to justify the cost on purely economic grounds. Mining NEAs seems to be a good kickstart approach.

  • Jon Lomberg September 23, 2013, 14:32

    The mission expects to be in contact with the spacecraft for a few decades after Pluto. My own opinion is that NASA always underestimates the operational lifetime of its spacecraft: the Viking landers were designed for a 90 day mission and lasted 7 years. Same for the MER rovers Spirt and Opportunity. And who knows what advances in sensitivity will come about, extending the range in which the spacecraft can be controlled? As for readability, the comment that ET will not be able to understand jpg or other compressed files is correct. We can not use standard file formats. One of the challenges is to encode the message in such a way as to make it obvious to spot and easy to understand. Quite a task, but I believe it is possible. Indeed, our project Advisors have already been taking about how to do it.

  • Laurel Kornfeld September 23, 2013, 15:03

    All together now, everyone send this message: Pluto IS a planet!!! :)

  • ljk September 23, 2013, 15:49

    This is certainly good news. Perhaps this effort will be the one that finally wakes up the space agencies and humanity in general that ALL deep space vessels, especially the ones leaving the Sol system for points unknown in the Milky Way galaxy, need information packages for their finders.

    ETI will learn something about the makers of the vessels, which will likely be inactive by the time they are found. Initially it will hopefully alleviate any concerns they may have about an unknown alien vessel. Then they will learn about us and our world, something we would no doubt greatly appreciate if an alien probe came wandering into our reach.

    The other benefit is to preserve knowledge and information about our species, civilization, and world that may not survive in other ways, especially if left on volatile Earth. Future human space explorers may really appreciate this rare and even unique knowledge from the early days of the Space Age, the effort that got them into the galaxy in the first place.

    Certainly the NHMI will be far more informative than what is on New Horizons now:

    http://www.collectspace.com/news/news-102808a.html

    Do the right thing, NASA, and thank you Jon Lomberg.

  • Joseph Moran September 23, 2013, 16:48

    Well, this is a bit of déjà vu. Way back before New Horizons launched, I was trading notes with Adolf Schaller and we tried to push for a Pioneer10-style postcard to be installed on NH. We figured no one would have time or energy for anything more. NH’s PR staff weren’t interested. Neither was Jon Lomberg at the time, we couldn’t get a response from him. I concluded the Pioneer & Voyager messages were a quirk of the 1970s unlikely to be repeated.

  • David September 23, 2013, 17:28

    Yes, great idea. I was thinking that once the message was sent to the
    “New Horizons” spacecraft, that it also be put on a CD or DVD for people to buy.
    The money could then be used to help pay for future events or initiatives and
    would also help raise public awareness of interstellar travel.
    I certainly would buy a DVD or CD. I recall that there was talk of putting the Voyager
    message on a record for sale ? Did that ever happen, and if so, does anyone
    know if any are still available ?

  • David A. Czuba September 23, 2013, 18:26

    I thought that the “discovered the earth” quote is attributed to Bill Anders of Apollo 8. I’m not sure how to confirm that.

  • ljk September 23, 2013, 19:21

    Joseph Moran said on September 23, 2013 at 16:48:

    “Well, this is a bit of déjà vu. Way back before New Horizons launched, I was trading notes with Adolf Schaller and we tried to push for a Pioneer 10-style postcard to be installed on NH. We figured no one would have time or energy for anything more. NH’s PR staff weren’t interested.”

    The following is quoted from this article:

    http://www.collectspace.com/news/news-102808a.html

    “After we got into the project in 2002, it was suggested we add a plaque and I rejected that simply as a matter of focus. We had a small team on a tight budget and I knew it would be a big distraction. I didn’t want to see us being distracted from the project and find ourselves derailing the project or getting into flight and finding we had some problem and wishing we’d have been more focused during development.”

    Not everyone agreed with Stern’s decision.

    “One individual on my team, one scientist, felt strongly we should have a plaque and protested that to NASA Headquarters, but NASA Headquarters agreed with me that we were taking the best course of action. We put that issue issue to bed in early 2003,” said Stern.”

    The paltry offerings placed onboard New Horizons and the lack of interest by most of the space probe team to create – or at least find individuals who would make the effort – information packages comparable to what is on Pioneer 10 and 11 and Voyager 1 and 2 had me talking to folks about making a group dedicated to creating information packages for deep space missions for all future endeavors.

    Thus the Faces from Earth effort was born:

    https://www.centauri-dreams.org/?p=11913

    https://www.centauri-dreams.org/?p=14247

    My quote from above:

    “The importance of being in essence respectful citizens of the galaxy and giving some kind of valuable legacy to our children is a driving force in the creation of Faces From Earth. It is designed to bring together people from multiple fields and disciplines across human culture to more fully represent the beings and items of our world to the Universe on all future deep space missions.”

    My extensive thoughts on messages and information about humanity and our world on deep space missions here:

    https://www.centauri-dreams.org/?p=26171

  • Alex Tolley September 23, 2013, 20:10

    @ Jon

    One of the challenges is to encode the message in such a way as to make it obvious to spot and easy to understand.

    I’ll be interested to read about that in a future post. As I recall, the “obvious” way to encode images by SETI was prime number x,y dimensions and just single bit values for the data. I hope we have advanced from that. :)

    Any thoughts about how you intend to address the hardware problem – how to access and read the files from a likely inert chip?

  • Eniac September 23, 2013, 20:16

    I do not share the concern about file formats as voiced above by Alex and Jon, so much. It is fair to grant ET intellectual abilities equal to ours, and us humans have demonstrated much more advanced capabilities of reverse engineering circuitry and decrypting cyphers than would be needed to recognize and read a memory chip and decode a JPEG or MP3 file located on it. No matter how alien.

    Still, for the benefit of the less intelligent ETs out there, we should probably include some type of Rosetta Stone and user manual, just to be sure.

  • steven rappolee September 23, 2013, 22:03

    I recall also having an email conversation with Dr Stern via email about a plaque, I think the concern was about weight and spacecraft center of gravity issues,
    I suggested a plaque in the star solid motor but this third stage gets hot during flight and every ounce of mass on the solid motor subtracts from the final payload mass.

    Dr Stern has over the last decade shown to me a more compassionate response to the fate of the solid motors trajectory, this has been posted years ago on the missions website.
    what we all should ask the mission team now is; where will the spacecraft and third stage be millienia from now? what star systems will these objects fly “near to”

  • Rickstar September 23, 2013, 22:28

    Brilliant idea!I can’t wait to see what Pluto will look like,up close!Godspeed new Horizons.IF this gets the “Green Light”,I would like to send out a road/starmap to Earth, & Sol,and a brief pictorial history of Earth,with music,much along the lines of Voyager.Captions,along side,many pictures could also be given,to help teach any alien finders of the New Horizons spacecraft,how to understand English,also.

  • CharlesJQuarra September 23, 2013, 23:08

    the ideal way to encode 2D images or other N-dimensional datasets is by making the sides of the square/cube a product of N prime numbers, so it will be obviously that the only way to arrange p1*p2 items is in a square shape. Compression would be a hard nut to crack, since the huge diversity in compression algorithms force any future decoders to explore an exponentially big space of encodings. But it is also true that we shouldn’t underestimate them too much. I guess jpeg could be decoded by some clever decoders after some time thinking about it.

  • Jon Lomberg September 24, 2013, 0:41

    The classic prime number picture matrix is indeed a method that could work here. Just strings of 1s and 0s that decode into pictures. I offer that as an alternative to anything else better– and hope we can devise something of equal elegant simplicity for sound. As for reading the data– that is the problem left to ET. But they are in a starship, so they’ve got some awesome instruments. I wish I shared Eniac’s confidence about reverse engineering what a jpg is. I think you could do it if you had the picture to work backwards from, but not without. A File Format Rosetta Stone (perhaps using prime number matrix pictures) is an excellent idea and one I encourage him to pursue. Being able to use compression increases the message complexity enormously.

  • Randy Chung September 24, 2013, 1:51

    An ET would have to know a lot about humans before they could decompress a JPEG or MP3. JPEG compression was developed using knowledge of the human visual system (the eye-brain system), and uses many different techniques with lots of “magic numbers”. Without a specification, it would be very very difficult to figure out the start codes, the Huffman codes, the zig-zag pattern, the quantization tables, the fact that DCT is used, that the image data is YCrCb rather than RGB, and many more details. MP3 is even more complicated, it gets its compression using a human psychoacoustic model and lots of digital filtering. The simplest encoding technologies would be better, like PCM, although they’d have the lowest compression.

  • David Cummings September 24, 2013, 7:51

    Just to be clear, 120MB is a fair amount of text space. A rough guide is 250 pages of text for 1MB, which means about 30,000 pages. If a standard text book is around 1,000 pages, this translates to 30 standard textbooks. It’s not the Library of Congress, but it’s not too shabby. You can put a lot of information in 30 standard textbooks. Of course, I’m talking about text only, non-unicode text only. Things change if images are included.

  • Doug M. September 24, 2013, 9:19

    TLDR: New Horizons should last until sometime in the 2030s, maybe the early 2040s, but certainly no more than that.

    Longer version: Paul, New Horizons is using a plutonium-powered RTG. (Specifically, a GPHS-RTG, which was the standard model for about 25 years. The newer model is the MMRTG, which is what MSL / Curiosity is using.) The power output of the RTG falls smoothly and steadily over time as the plutonium decays. So New Horizon’s lifespan is ultimately limited by the power output from the RTG; when that falls too low to power its instruments, heater, and radio, it will die.

    Things are complicated slightly by some uncertainty on the degradation rate of the RTG. The half life of the plutonium is known, but there is also degradation due to radiation damage to the bimetallic junctions in the thermocouples that generate power. Over time this adds a few percent of uncertainty into power output projections, which is why even the most meticulous prediction is always approximate.

    New Horizon’s RTG was giving about 240 watts at launch, and will still be about 200 watts at Pluto. Much below 200 watts and the instruments have to start cycling. Cruise mode requires 150 watts (for basic functions like radio and heating).

    That 150 watt level is the point where NH’s survival begins to get really iffy. On current extrapolations, it is expected to be reached in the early 2030s. There’s probably a margin for error built in there, and Voyager has shown us that clever power management can, by various tricks, eke out a bit more performance than the original design specs. Nevertheless, by 2040 the inexorably declining output line will be down below 120W, and it’s hard to see how the machine can survive much past that.

    New Horizon won’t live as long as the Voyagers (who are expected to get within shouting distance of 50 years before falling silent), because its RTG is not as big. The Voyagers — luckily for us — turned out to be a bit overpowered. It was the 1970s, space exploration was still young, so the engineers were designing in bigger margins of error. Still, 30+ years would be very respectable.

    Doug M.

  • Doug M. September 24, 2013, 9:23

    Here’s a cite for the above. Note particularly the graph on page 25, and the discussion on pgs. 28-31.

    http://www.boulder.swri.edu/pkb/ssr/ssr-fountain.pdf

    Doug M.

  • Joseph Moran September 24, 2013, 14:12

    Hi folks. Nice to see there were others thinking a postcard was a good idea at the time. But I have to agree with Stern and NASA HQ: the mission’s future was precarious enough without bringing in this issue. Just for grins, I looked in my archives to see if I still had the proposal we sent out. Here’s a link to the PDF. It was a fun exercise that got me through a hard time between jobs.

    https://docs.google.com/file/d/0B4FFIpqStnhjeTl6LXBNcHZHM1k

  • Eniac September 24, 2013, 21:41

    I agree with David Cummings that text would be more meaningful and efficient to send, particularly if memory space is limited. A picture may say as much as a thousand words, but it takes a lot more memory. Besides, we do not know if the ETI can actually see. To a blind person, an image is meaningless, but a book reads just the same.

    No need to mess with the alphabet, just number the words and send the numbers. 16 bit words would cover a pretty nice vocabulary of 65536 words, a little less than Shakespeare, perhaps, but enough to get a lot of points across. A carefully crafted tutorial on the language would help, the rest is just transcribing encyclopedias, literary masterworks, cookbooks, science texts, whatever the committee decides to include.

    Wikipedia, perhaps? Mmmmh, probably too big…..

  • Heath Rezabek September 24, 2013, 22:24

    @Charles – That’s an intriguing idea, regarding using prime numbers to shape the square. I wonder if some similar sort of approach to compression could be used; a compression scheme developed which may not be the most efficient compression, but which contains in itself clues to its own decompression. After all, compression and cryptography are two sides of the same coin.

    In general, here’s another thing I think it’s important to remember: When dealing with very long term messaging or archival, the fate of any single instance of the message is less important than the fact of arriving at any sort of message at all, as that suggests the potential for casting it into other future additional forms or formats. The idea of an upgradeable, versioned message from Earth is a tremendous one, regardless of the lifespan of New Horizons’ chipsets.

  • ljk September 25, 2013, 13:12

    Joseph Moran said on September 24, 2013 at 14:12:

    “Hi folks. Nice to see there were others thinking a postcard was a good idea at the time. But I have to agree with Stern and NASA HQ: the mission’s future was precarious enough without bringing in this issue.”

    I find this argument to be bogus. The New Horizons team had no problem putting various items on board that had NO benefit towards the mission whatsoever. They even put some of Clyde Tombaugh’s ashes in a container attached to the probe, and please do not tell me that did not require some effort to get approval from NASA.

    As with Pioneer and Voyager, the mission team could have gotten some outside help to create a proper information package for the probe. Joseph, your updated Pioneer Plaque would have done nicely. Instead we have a probe with items that one often finds in a typical small town time capsule. Perhaps that will speak volumes to the finders about the current members of our species, human or otherwise.

    http://paleofuture.gizmodo.com/this-week-in-time-capsules-lost-steve-jobs-capsule-h-1356021778

  • ljk September 25, 2013, 13:18

    Coolest Time Capsule Ever Has Left The Solar System

    Paleo-Future

    Arguably one of the coolest time capsules ever created was in the news this week. NASA finally determined that Voyager 1 officially left the solar system around August 25th of last year. Voyager 1 includes the Golden Record, perhaps best described by President Jimmy Carter:

    “This is a present from a small, distant world, a token of our sounds, our science, our images, our music, our thoughts and our feelings. We are attempting to survive our time so we may live into yours.” Float on, little buddy. And may the aliens that find you have a bitchin’ hi-fi system.

    http://paleofuture.gizmodo.com/this-week-in-time-capsules-best-capsule-ever-leaves-th-1303813828

    A needle and stylus were included with both Voyager Interstellar Records. If the finders can do nothing else, they can run the needle in the grooves and listen to the audio portions of the record. Cannot do that with a CD, which is also subject to degradation by cosmic rays.

  • Eric W.Davis September 26, 2013, 0:52

    Unfortunately, as Doug Vakoch (SETI Inst.) has shown over the years, the incommensurability problem between human linguistics (which includes mathematical messages and coding schemes) will not be understandable by any alien species that evolves in a different environment and uses different physiological sensory devices to gain knowledge and build a model of the universe as they observe it using those senses. A putative platform for crossing that bridge will rely on a clever adaptation of semiotics.

  • Eniac September 28, 2013, 12:05

    Eric W Davis:

    … the incommensurability problem between human linguistics (which includes mathematical messages and coding schemes) will not be understandable by any alien species …

    I am not sure I understand. Surely “mathematical messages” such as a series of prime numbers will be understood by ANY intelligence that has pondered mathematics, ever. As numbers are understood, ways of coding them, will too. Mathematical quantities, such as Pi or e will be universally recognized, as will physical quantities such as the fine structure constant.

    A simple example: Say we received a message with groups of dots counting out prime numbers. Then, a series of, say, octal codings of the same numbers. Then, the fine structure constant in that same octal representation, but with 15 more digits of accuracy than we are able to measure ourselves. The message is: “We are here, we know math, we know physics, we are more advanced than you, and here is a better estimate of alpha than you ever dreamed possible”.

    Are you (or Vakoch) saying that this sort of message will not be understood? Which part of it and why?

    If not, what then are you saying?

  • Alex Tolley September 29, 2013, 11:06

    @Eniac.

    Keith Devlin did a talk at SETI about why communication with mathematics is not necessarily going to work for alien communication.
    https://www.youtube.com/watch?v=KveKjHIipgo

    The late John McCarthy argued that intelligence was subject to convergent evolution. This supports the argument that mathematics, at least in the abstract, may be common to all intelligences.
    https://www.youtube.com/watch?v=kvIqc0aBR0A

    I attended the McCarthy talk but was not really convinced by his argument. I have watched the Devlin talk, but I found it a little hard going to follow his argument.

  • Eniac September 29, 2013, 22:20

    @Alex Tolley: Interesting references, but what say you about my specific example? Likely to be understood by ETI, or not, and how possibly not?

  • Alex Tolley September 30, 2013, 14:23

    @ Eniac – you would have to assess that yourself. I think the point is that we build in a lot of assumptions about aliens that may make transmissions unintelligible. BTW, I just read “Barid’s “The Inner Limits of Outer Space” (1986) that Paul Gilster had recommended a while back. Baird is [was?] a psychologist and he tries to unpack many of the SETI communication models to show how they may not be understood – in either direction. We assume math is universal, but how math is constructed and conveyed in a signal may prove more difficult than we think.

  • ljk October 1, 2013, 0:20

    Actually I recommended Baird’s book here:

    https://www.centauri-dreams.org/?p=27889

    My article discusses the book Civilizations Beyond Earth which looks at SETI and alien life from the perspectives of biologists, anthropologists, historians, and sociologists.

    I also strongly recommend the reading of this book which is online plus linked to and quoted in my article:

    http://www.daviddarling.info/encyclopedia/S/SETI_critical_history_cover.html