Sciency Words A to Z: SETI

April 22, 2019April 21, 2019 ~ J.S. Pailly ~ 7 Comments

Welcome to a special A to Z Challenge edition of Sciency Words! Sciency Words is an ongoing series here on Planet Pailly about the definitions and etymologies of science or science-related terms. In today’s post, S is for:

SETI

In September of 1959, Italian physicist Giuseppi Cocconi and American physicist Philip Morrison published this paper, titled “Searching for Interstellar Communications.” That paper is essentially the founding document for SETI, the search for extraterrestrial intelligence, which is now considered a subfield of astrobiology.

The SETI Institute, on the other hand, was established in 1984 by Thomas Pierson and Jill Tarter. As stated in this report on the proper use of SETI nomenclature:

SETI should not be used as a shorthand for the SETI Institute, which is an independent entity and should be referred to by its full name to avoid confusion.

And let me tell you, this SETI vs. SETI Institute distinction… that really can cause a lot of confusion.

A few years back, I saw a report on the news. SETI (the Institute, I presumed) had picked up a signal form outer space, from a star located 94 light years away. According to the news lady on TV, a SETI spokesperson had this to say, and that to say, and some more stuff to say about this amazing discovery. “Oh cool,” I thought, and I quickly went to the SETI Institute’s webpage to learn more.

There was nothing—absolutely nothing—about it.

Another day or two went by, and then this article was posted on the SETI Institute’s website. Some Russian radio astronomers had picked up what they thought was a SETI signal (it eventually turned out to be a satellite). Somehow the media picked up on this story and ran with it, apparently without contacting the SETI Institute—or speaking with any actual SETI Institute spokesperson—to find out if any of this were true.

I should probably mention that in my day job, I work in the T.V. news business. This sort of sloppy journalism infuriates me, but I’ve found that it’s quite typical of how the popular press handles science news.

However, to be fair, prior to that misleading news report, I didn’t know to make a clear distinction between SETI and the SETI Institute myself. But I’ve tried to be more careful about this ever since. Language can be a messy way to communicate, so it’s important to try to be clear about what we mean. Otherwise, someone (perhaps even someone from the media) will get the wrong idea and run with it.

Next time on Sciency Words A to Z, the first astronauts on Titan may find themselves in a very sticky situation.

Sciency Words A to Z: METI

April 15, 2019April 12, 2019 ~ J.S. Pailly ~ 14 Comments

METI

In a sense, SETI researchers are just sitting by the phone waiting for somebody to call. Maybe that’s the wrong way to go about it. Maybe it’s time to pick up the phone, start dialing numbers, and see who picks up.

This idea is sometimes called active SETI, but it’s more common (and according to this paper, more appropriate) to use the term METI: the messaging of extraterrestrial intelligence.

Earth has been broadcasting TV and radio signals for over a century. This has led to a common misconception that even now, aliens on some far off planet might be gathering around their equivalent of a television set, watching old episodes of Howdy Doody or The Honeymooners. Or perhaps, if the aliens live nearby, they’re currently listening to our more recent music.

But Humanity is only a Type 0 or Type I civilization, depending on which version of the Kardashev scale you’re using. Either way, our broadcasts are not actually that strong. As David Grinspoon explains in his book Earth in Human Hands:

Our television signals are diffuse and not targeted at any star system. It would take a huge antenna, much larger than anything we’ve built or planned, to pick up on them. From a radio point of view our planet is not completely hidden, but it is hardly conspicuous. This could easily change. Targeted messages sent directly toward nearby stars would cause Earth suddenly to turn on like a spotlight, becoming an obvious beacon announcing, for better or worse, “We are here!”

Of course we’ve already done this. Several times, in fact. But not with enough consistency to truly make our presence known.

The first attempt was in 1974, when Frank Drake and Carl Sagan transmitted a message from the Arecibo radio telescope in Puerto Rico, aimed at the M13 globular cluster. But according to Grinspoon, if aliens ever do pick up that signal, “[…] they might dismiss it as a momentary fluke. We would.” That’s because the Arecibo message was a quick, one-time thing. By itself, it’s hardly proof beyond a reasonable doubt that life exists on Earth.

If we really want to get somebody’s attention, we have to send a sustained, repetitive signal, kind of like those repetitive radio pulses Jocelyn Bell detected in the 60’s. We have the technology. We can make METI a reality. But should we? Some say yes, others no. After all, we have no idea who might hear our signal, or what form their response might take, and there is no guarantee that the aliens will be friendly.

METI is a discussion and a debate that maybe we all, as a species, should be part of. Perhaps we should take a vote, because in the end, we all have a stake in what might happen. And while we’re at it, there are some other issues we all, as a species, should vote on. Or at least that’s what Grinspoon says we should do in his book.

Next time on Sciency Words A to Z, we’ll go back in time and check out the oceans of Mars.

Sciency Words A to Z: Kardashev Scale

April 12, 2019April 11, 2019 ~ J.S. Pailly ~ 16 Comments

KARDASHEV SCALE

In 1963, Soviet scientist Nikolai Kardashev published this paper concerning the search for extraterrestrial intelligence. Kardashev seems to have been primarily interested in how much information aliens might be able to transmit to us across the vastness of space. This, in turn, relates to how much energy an alien civilization is able to produce, because the more energy you have, the stronger your radio signals can be.

Kardashev summarized his thoughts on this by devising a scale—now known as the Kardashev scale. In Kardashev’s original system, there were only three types of civilizations:

Type I: a civilization that has harnessed energy on a planet-wide scale. Kardashev considered Earth to be a Type I civilization.
Type II: a civilization that has harnessed the energy of an entire star, perhaps by building a Dyson sphere or some other megastructure around their own sun.
Type III: a civilization that has harnessed the energy of an entire galaxy. Kardashev doesn’t offer any examples of this, but I might point to something like the Galactic Republic/Galactic Empire in Star Wars—they’re approaching Type III status.

Later scientists have expanded on the Kardashev scale. Humanity has been demoted to a Type 0 civilization, because we don’t really use all the energy available to us on our planet. Not yet, at least.

We can also talk about Type IV civilizations, which can harness the energy of the whole universe, and Type V civilizations, which can harness all the energy of the multiverse, or perhaps all the energy of alternative timelines, or something like that. Examples? I don’t know, maybe the Timelords from Doctor Who or the Q-Continuum from Star Trek. Or maybe these people.

So which of these civilizations should we expect to find out there? What sort of transmissions do we expect to see?

The problem with Type IV and V civilizations is that their activities would be, to us mere mortals, virtually indistinguishable from nature. As for Type 0 and Type I, their radio signals (if they’re sending any) may be too weak for us to detect over all the background radiation of the cosmos.

But the Type II and Type III civilizations… Kardashev was pretty optimistic about our chances of finding them. In his 1963 paper, Kardashev argues that it’s absurd to think Earth is the only planet with intelligent life, and furthermore most alien civilizations should be far older and far more advanced than we presently are. You may recall Enrico Fermi made a similar argument.

So there should be plenty of Type II civilizations out there, and perhaps a few Type IIIs as well, all chattering away in loud, easy-to-detect radio transmissions. Or so Kardashev claims. “In any case, the deciding word on this question is left to experimental verification,” he wrote. But after fifty years of trying to detect something… anything… what has the experimental evidence shown us?

That’s a fair question. And yet I have to agree with Kardashev: it is absurd to think Earth is the only planet with intelligent life. So once again, in the immortal words of Enrico Fermi, where is everybody?

Next time on Sciency Words A to Z… wait, did we detect a signal? Nope. False alarm.

Sciency Words A to Z: Intelligence

April 10, 2019April 7, 2019 ~ J.S. Pailly ~ 8 Comments

INTELLIGENCE

In 1959, this paper by Giuseppi Cocconi and Philip Morrison appeared in the journal Nature. The ideas Cocconi and Morrison laid out in that paper were bold, and maybe a little presumptuous, but they became the foundation for a very important subfield of astrobiology: the search for extraterrestrial intelligence, or SETI for short.

The A to Z Challenge being what it is, it’s too early for us to start digging in to the subject of SETI research. But we can talk about part of it. Specifically the I part—“intelligence.” It’s fairly obvious what “search” means, and “extraterrestrial” simply refers to something that’s not from Earth. But what is the definition of “intelligence”?

What does it mean to be intelligent? How would we recognize an extraterrestrial intelligence if and when we find one? Are we sure we humans are a good example of what an intelligent life form is like? (No, wait, maybe don’t answer that last one!)

In this article from Space.com, the famous SETI scientist Jill Tarter is quoted as saying:

SETI is not the search for extraterrestrial intelligence. We can’t define intelligence, and we sure as hell don’t know how to detect it remotely. [SETI]… is searching for evidence of someone else’s technology. We use technology as a proxy for intelligence.

This reminds me of a joke from the Hitchhiker’s Guide to the Galaxy, that humans think we are the most intelligent creatures on Earth because we built cities and nuclear weapons and things like that, while dolphins believe they are more intelligent than us because they chose not to do those things.

So it is time we change SETI to SETT—the search for extraterrestrial technology? It sounds like Tarter would support that change. She calls the SETI acronym “problematic” and suggests that we “talk about a search for technosignatures” instead. But as regular readers of Sciency Words should know by now, once a word gets embedded in the scientific lexicon, it’s really, really, really hard to change it, no matter how problematic it might seem. Don’t believe me? Click here or here or here or here or here.

And I suspect that Jill Tarter knows this. In this report on SETI nomenclature, which is co-authored by Tarter, it says, “Definitions of intelligence are slippery […]” however, “[the word’s] use in the acronym SETI is sufficiently entrenched that we recommend against a more precise rebranding of the field.”

So what does it mean to be intelligent? For the purposes of SETI, no one knows. The term is vague to the point of being unusable for official scientific discourse. But scientists have been talking about and writing about this for decades—remember, that Cocconi-Morrison paper came out in 1959—so at this point we’re sort of stuck with the I in SETI.

Next time on Sciency Words A to Z, we’ll get the latest juicy gossip from the moons of Jupiter.