THE SILURIAN HYPOTHESIS AND ITS SCARY IMPLICATIONS

On By AlessandraIn Ancient Civilizations, Silurian Hypothesis

The Silurians are fictional creatures that appeared in an episode of the cult science fiction TV show Dr. Who. In the story, these lizard-like creatures achieved industrial expertise about 450 million years ago, long before humans evolved on Earth.

In recent years, the idea of advanced prehistoric life has turned out to be intriguing far beyond its entertainment value, raising various exciting questions. Not least is this: if an industrial civilization had existed in the past, what traces would it have left? In other words, how do we know that ours is the first technological civilization on Earth?

Modern humans have been around for 200,000 years, but life has existed on this planet for 3.5 billion. That leaves more than enough time for the rise and fall of not one but several pre-human industrial civilizations. Yet, so far, little serious thought has been given to the possibility that we are not the first species to build a civilization in the Solar System’s history.

We’re used to imagining extinct civilizations in terms of underwater statues and subterranean ruins. These artifacts of previous societies are acceptable if we are only interested in timescales of a few thousand years. But things get trickier once we are interested in “deep time,” meaning tens or hundreds of millions of years ago. It is unlikely that any massive artificial structures would remain preserved through eons of geological activity.

Urban areas presently comprise less than 1% of the Earth’s surface. So any comparable settlements from an earlier civilization would be easy for modern-day paleontologists to miss. And no one should count on finding a Jurassic-era artifact, e.g., the Antikythera mechanism, used by the ancient Greeks and considered the world’s first computer. Complex items don’t last millions of years. The same is true for fossils of beings who might have lived in industrial civilizations. Moreover, the fraction of life that gets fossilized is tiny; of all the many dinosaurs that ever lived, only a few thousand fossil specimens have been discovered. Given that the oldest known fossils of Homo Sapiens are only about 300,000 years old, there is no certainty that our species might even appear in the fossil record in the long run.

For these reasons, Adam Frank, a physicist at the University of Rochester, and Gavin Schmidt, director of NASA’s Goddard Institute for Space Studies, have recently focused on what kind of signature a technological species might leave behind.

Fig.1: Intelligent dinosaurs in an ancient technological civilization. Picture made by the author with Midjourney AI.

The best way to answer this question is to figure out what evidence we would leave behind if our civilization collapsed at the current stage of development.

Humanity’s collective activity is laying down a variety of traces that will be detectable by scientists 100 million years in the future. The extensive use of fertilizers, for example, means we’re redirecting the planet’s nitrogen flow into food production. Future researchers should see this in characteristics of nitrogen showing up in sediments from their era. And then there’s all the plastic.

Increasing amounts of plastic are deposited on the seafloor everywhere, even in the Arctic. Sooner or later, all this plastic turns into microscopic particles, creating a layer that could persist for geological timescales. Still, the most promising marker of humanity’s presence is the carbon released into the atmosphere as a by-product of the burning of fossil fuels. This ancient carbon derives from plant life, which preferentially absorbs more of the lighter isotope carbon-12 than the heavier isotope carbon-13. The more fossil fuels we burn, the more the balance of these carbon isotopes shifts. Temperature increases also leave isotopic signals.

So if these are traces our civilization is bound to leave for the future, might the same “signals” waiting to be uncovered right now in ancient geological strata? Fifty-five million years ago, global temperatures rose from 9 to 14 degrees Fahrenheit. This is called the Paleocene-Eocene Thermal Maximum (PETM). During the PETM, Earth’s surface temperature rose because of a sudden release of greenhouse gases from the Earth’s crust. These greenhouse gases caused the climate to warm and the ocean to become more acidic. Such environmental conditions may have led to the extinction of most of the dinosaurs.
There are also other similar events in Earth’s history. For example, an event that occurred only a few million years after the PETM is called the Eocene Layers of Mysterious Origin. More massive events in the Cretaceous left the ocean without oxygen for millennia.

These events are almost certainly not caused by previous non-human civilizations. The present era (known as Anthropocene) is remarkable because of the speed at which we dump fossil carbon into the atmosphere. There have been geological periods where Earth’s CO2 has been as high or higher than it is today, but never before in the planet’s long history has so much buried carbon been dumped back into the atmosphere so quickly. Still, the PETM carbon isotope spike mostly shows Earth’s timescales for responding to whatever caused it, not necessarily the timescale of the cause. Finding evidence of a short-lived event in ancient sediments might take reliable and novel detection methods.

Fig.2: Two hypothetical members of a long-gone industrial civilization. Picture made by the author with Midjourney AI.

HOW TO TALK TO YOUR GENIUS CAT

On By AlessandraIn Cats, Wolfram "Morsy" Chettoh

Some experts (for example, Kalla J. Knopman in the already mentioned How to Measure  Your Cat’s IQ) say we shouldn’t talk “human” to cats. Instead, we should try to imitate their language so that they, in turn, can imitate us.

My experience with Wolfram Chettoh, whom I’ve owned for more than thirteen years, tells a different story. Cats have no problem understanding our language. Sometimes they may ignore us, but it’s almost always a pretense. So, there is no need to make ourselves ridiculous with pitiful attempts at feline language. Cats will usually act disgusted and annoyed when not outright scared.

Indeed, devilish genius cats can choose several ways to communicate with humans.

Wolfie Chettoh can do the following:

VERBAL COMMUNICATION:

(1) meowing:

Figure 1: Wolfie “Morsy” Chettoh in August 2018. Photo by the author.

This is standard cat talk. However, Chettoh seldom meows, with rare exceptions. When he was a kitten, Chettoh used soft meowing for whatever necessity. Then, his communication techniques began to diversify as his cognitive function evolved.

(2) complaining:

Figure 2: Wolfie “Morsy” Chettoh in July 2011. Photo by the author.

This is a long, high-pitched lament. Chettoh complains when he fears I might forget about him. It happens either when I come home after a long day at work, and I’m not fast enough to take care of his needs before anything else or when I’m about to leave. Chettoh always knows when I’m getting ready for work (see the previous post). Other occasions to complain are when I’m doing something stupid and pointless (from a cat’s point of view), like trying to fix a bathroom leak or another emergency around the house. Chettoh doesn’t like intense noises, like hammering on something or vacuum-cleaning.

A variant of the complaint sound is the “hurry up” call. This is a fast, impatient “meow,” telling you to get a move on when filling Chettoh’s bowl.

(3) chirping:

Figure 3: Wolfie “Morsy” Chettoh in July 2012. Photo by the author.

A deep, short rumble is Chettoh’s way of thanking you. Most of the time, Chettoh is a well-behaved cat, so he’ll say “thank you”  when you feed him, stroke his head, or indulge him, like when he wants me to pick up and carry him to his food bowl. In general, Chettoh chirps to greet you when he wakes up after one of his frequent naps.

(4) growling:

Figure 4: Wolfie “Morsy” Chettoh in April 2020. Photo by the author.

Chettoh seldom growls, but when he’s distraught. As I explained in the previous posts, he’s been my favorite pet for thirteen years. During this time, we only had a few fights, most of which can be attributed to my (often) limited understanding of a cat’s personality and behavior. For example, I thought I’d lost my precious iPhone a couple of years ago. Before I found out I’d forgotten it in a restaurant, I was so upset that I began muttering: “Oh my goodness! Where is the f… phone? What am I going to do? My phone! Oh no, I lost my phone!” And so on. Now, cats are good judges of human moods. Chettoh, in particular, immediately understands when I’m annoyed, even from rooms away. The only problem is that he usually thinks I’m angry AT HIM. Consequently, before I turn aggressive (I wouldn’t, but that’s what his predator mind tells him), he hits first. Before fully grasping what was going on, I realized the growling little monster had sunk his teeth and claws into my right shin.

NON-VERBAL COMMUNICATION:

(5) purring:

As a kitten, Chettoh seldom purred. Only when I picked him up, and he wanted to show his harmlessness, did he display this most peculiar cat behavior. Getting older and more socially clever, Chettoh purrs much more often. For example, he purrs when he greets me after work, when he’s eating, when he lies on my computer keyboard (and I’m trying to use it) when my friends come to visit, and they want to cuddle him, and also when I’m sad, and he wants to cheer me up. However, as most cat owners know, cats purr not only when they are happy or friendly. Some cats will purr when sick or aching, like a she-cat I used to have as a teenager, who softly purred right until she died (probably from eating poisoned food).

Figure 5: Wolfie “Morsy” Chettoh in June 2019. Photo by the author.

(6) twitching the tail:

Figure 6: Wolfie “Morsy” Chettoh in October 2022. Photo by the author.

Like most adult cats, Chettoh “speaks” a lot with his tail. This happens when he is happy (vertical, parading tail) or angry (low, left-to-right, fast swishing tail). Indeed, a sure indicator that a cat is about to attack is the rapid movement of its tail. This happened on the occasion I told above. However, I didn’t know my kitty enough at the time to catch the red flag. Chettoh also uses his tail when he’s too lazy to meow. For example, when Chettoh is pretending to sleep next to where I’m working at home, if I ask him a question like: “Did you eat your food?” or: “Would you like some more food?” he twitches his tail twice. Of course, if the question is, “Did you make that mess in the carpet?” he puts on his “Sleeping Furry Beauty” act, worthy of an Academy Award. Sometimes, Chettoh uses his tail to express curiosity. When he’s investigating a strange noise, for instance, or trying a new kind of food, he shapes his tail like a question mark.

(7) rubbing the head on your leg, ankle, or a nearby object:

Apart from the usual rubbing against your ankles, which many cats use to transfer their scent and claim you as “property,” grown cats may use this kind of non-verbal communication for more complex reasons. Lately, for example, Chettoh has adopted what I call the “Muttley talk,”  from the name of the dog character in the 70s Hanna-Barbera Productions TV series Dastardly and Muttley in Their Flying Machines. In that funny cartoon, Muttley, the dog, used to point at his chest to ask for a medal. Similarly, when Chettoh wants to be stroked, he first jumps on the nearby tallest spot, then rubs his head on something and repeatedly points at it with his right paw.

Figure 7: Wolfie “Morsy” Chettoh in November 2022. Photo by the author.

Rating Chettoh’s non-verbal communication:

According to Kalla J. Knopman’s Measure Your Cat’s IQ,

(a) “if your cat has a unique way of expressing itself […], give kitty 5 points.”

       As explained above, Chettoh has many peculiar ways to express himself, like the “Muttley Talk,” so I’ll award him five points;

(b) “Give 3 points if the kitty meows to get your attention when another cat or human does something wrong.”

       Chettoh doesn’t meet many people, so when he meows at someone, that’s usually me. Three more points to Chettoh, then.

Great Sci-Fi Novels 3: Jack Vance’s ‘The Demon Princes’

On By AlessandraIn Books, Reading, Writing

The Demon Princes is a galactic saga that Jack Vance wrote in five installments: The Star King (1960), The Killing Machine (1964), The Palace of Love (1965), The Face (1978), and The Book of Dreams (1979). It draws upon elaborate worldbuilding, which the author introduces in the form of “sources,” e.g., imaginary magazines, scientific papers, and textbooks describing exotic planets, alien peoples, strange rules, and customs. Quoted at the beginning of a chapter, these fictional sources minimize the need for long descriptive paragraphs.

Here are a few examples taken from the first novel, The Star King:

Chapter 1:

From an interview with Mr. Smade of Smade’s planet, a feature article in Cosmopolis, October 1523:

A short Q&A introduces the reader to the concept of Beyond, short for  “Beyond the Pale” or border, which separates the group of solar systems explored and settled by humans from the largely unknown Galaxy.

Most of the action revolves around the adventures of Kirth Gersen, an enigmatic character seeking revenge for the kidnapping and enslavement of his people. To this end, Gersen must confront five cruel overlords, the Demon Princes. The confrontations usually happen in the Beyond, a place, according to Mr. Smade, “frequented by the most notorious pirates and freebooters.”

Chapter 2:

From an article in Cosmopolis, May 1404:

Here Vance introduces Brinktown: “Once the jumping-off place, the last outpost, the portal into infinity – now just another settlement of the North East Middle Beyond.” As is often the case in SF novels, Brinktown seems to be both the name of the planet and the city, the latter being portrayed colorfully: “an explosion of architectural conceits, what turrets and spires, belfries and cupolas… the magistrates are assassins; the civil guards are arsonists, extortioners, and rapists.” We cannot help thinking of Star Wars Mos Eisley: “Not a more wretched collection of villainy and disreputable types exists anywhere on Tatooine.”

Chapter 4:

From New Discoveries in Space, by Ralph Quarry:

“The Rigel Concourse… twenty-six magnificent planets, most of them not only habitable but salubrious, though only two display even quasi-intelligent autochthones.”

When Kirth Gersen isn’t hunting for one of the Demon Princes beyond the Pale, he usually hangs around the Rigel Concourse, the planetary system of the blue supergiant star Rigel. According to Jack Vance, Rigel has twenty-six planets, of which Alphanor – the setting of most of the first novel – is the eighth. Jack Vance based the worldbuilding of The Star King on the early sixties astronomy. However, SF authors should be careful not to be too specific when including real planets or stars in their stories. What was then state-of-the-art knowledge soon became obsolete. It has been known for decades that extremely short lifetimes prevent blue supergiant stars like Rigel from developing habitable planets (before they turn into neutron stars or black holes).

Another good example can be found in the second novel, The Killing Machine:

Chapter 3:

From Chapter 1, The Astrophysical Background, in Peoples of the Concourse, by Streck and Chernitz:

The quotation at the beginning of the chapter partially answers the objections we raised above:

“But the very circumstances which make the Concourse what it is, provide one of the galaxy’s most tantalizing mysteries. Rigel is deemed by most authorities a young star, ranging in age from a few million to a billion years. How then to explain the Concourse, [with its] twenty-six mature biological complexes? [Some] have wondered if the planets of the Concourse were not conveyed hither and established in these optimum orbits by a now-dead race of vast scientific achievement.”

In other words, plot holes in SF stories stretching over several novels can be retroactively fixed with accurate worldbuilding in the next installments. To quote a famous example, this is what happened with some inconsistencies in the Star Wars Original Trilogy (1977-83), e.g., Leia kissing Luke, who turns out to be her brother, and Leia remembering her biological mother, who died in childbirth. All apparent errors were later explained in the “prequels” (1999-2005) and recent spin-offs like Kenobi (2022).

WHAT WOULD BE A GREAT PLACE TO SEARCH FOR ET?

On By AlessandraIn Extrasolar Planets, S.E.T.I.

The Dyson sphere is a hypothetical megastructure physicist Freeman Dyson proposed in 1960.

According to his paper published in Science magazine, a technologically advanced alien civilization would use increasing energy as it grew. As the most significant source of energy in any solar system is the parent star, sooner or later, the civilization would build orbiting solar panels to try to capture it. Such structures would take up more and more space until they eventually covered the entire star like a sphere.

In a 2008 interview with Slate, Dyson also credited the concept to writer Olaf Stapledon, who introduced it in his novel Star Maker in 1937.

Dyson’s hypothesis turned out to be hard to verify because a complete Dyson sphere, absorbing all of the light from the star, would be invisible to an exo-planet hunting telescope (such as NASA’s Kepler). Only half-completed spheres would have a chance to be discovered.

Unfortunately, a Dyson sphere is unlikely to remain under construction for long. The time it takes to make a Dyson sphere is relatively short. A 2013 paper by Stuart Armstrong and Anders Sandberg (“Eternity in six hours: Intergalactic spreading of intelligent life and sharpening the Fermi paradox”) estimates that disassembling Mercury to make a partial Dyson shell could be done in 31 years.

An alternative would be to look for waste heat in the infrared. After being absorbed and used, the energy from a star needs to be reradiated, or else it would build up and eventually melt the Dyson sphere. This energy would be shifted to longer wavelengths so that a Dyson sphere might give off a peculiar energy signature in the infrared. In other words, Freeman Dyson saw a search for his namesake spheres as a complement in the infrared to what Frank Drake’s Search for extraterrestrial intelligence (SETI, see previous blog post) had begun to do with radiotelescopes.

Carl Sagan and Russell Walker first voiced an issue with Dyson’s SETI notion in their 1966 paper “The Infrared Detectability of Dyson’s Civilizations” for the Astrophysical Journal. The authors noted that:

discrimination of Dyson civilizations from naturally occurring low temperature objects is very difficult, unless Dyson civilizations have some further distinguishing feature, such as monocromatic radio-frequency emission.

In the following decades, the search for Dyson spheres expanded dramatically. Starting from the 1980’s researchers went to work using sources identified by the Infrared Astronomical Satellite (IRAS). These early searches produced little o no results, as most Dyson sphere candidates had either non-technological explanations or needed further study. Subsequent investigations using NASA’s space-based WISE (Wide Field Infrared Survey), with higher resolution than IRAS, have all concluded that the identification of a promising source would not in itself be proof of an extraterrestrial civilization unless the object could be followed up with more conventional methods, such as laser or radio search.

Among the latest developments concerning Dyson spheres are the following:

  • Dyson spheres could be built around black holes instead of stars.

Black holes can radiate incredible amounts of energy (105 more energy than the Sun) produced by the so-called “accretion disk” of gas and dust falling into the black hole’s maw. As a consequence of their spiraling and spinning motions, these materials heat up through friction to millions of degrees, emitting extremely energetic X-ray photons.

But why would an alien civilization decide to build a Dyson sphere around a distant black hole (if it weren’t “distant,” the civilization would have been “eaten” long before it managed to construct the sphere) rather than using their much closer parent star? Black holes concentrate an enormous mass into a space area that is orders of magnitude smaller than a star’s, and are therefore easier to encircle. On the downside, black holes often have bursts of activity followed by quiet periods as they consume varying lumps of matter in their disks. An alien species woulod have to protect their orbiting structures from the huge explosions that might destroy them.

  • Dyson spheres could be circling the husks of sunlike stars known as white dwarfs.

Every star has a finite lifetime. If a civilization arose around a typical sun-like star, then someday that star would turn into a red giant and leave behind a white dwarf. That process would roast its solar system’s inner planets and freeze the outer ones as the white dwarf cooled off. Consequently, the civilization would have to choose between moving to another system or building a series of habitats that harvest the radiation from the remaining white dwarf. It seems unlikely that a civilization, no matter how advanced, would go through the enormous effort of traveling to another star only to build a Dyson sphere.

This allows a direct connection between stellar lifetimes and the prevalence of Dyson spheres.

If enough aliens decided to build Dyson spheres around their white dwarf homes, then astronomers should find at least one Dyson sphere in white dwarf surveys. The presence of a megastructure like a Dyson sphere around a white dwarf would absorb part of its radiation and convert it into reusable energy. Since no conversion is 100% efficient, this process would leave behind waste heat that would escape as infrared light.

Astronomers have already found many white dwarfs with excess infrared emission, usually explained as dust in those systems, not megastructures. According to a paper by Ben Zuckerman and recently accepted for publication in the journal Monthly Notices of the Royal Astronomical Society, no more than 3% of habitable planets around sunlike stars give rise to a white dwarf sphere-building civilization. Still, there are so many planets orbiting sunlike stars that this calculation only provides an upper limit of 9 million potential alien civilizations in the Milky Way.

CATS AND SYMBOLS. DO THEY REALLY GET THEM?

On By AlessandraIn Cats, Wolfram "Morsy" Chettoh

Does Wolfie Chettoh understand symbols? The answer is yes, if you consider a sad Covid face mask a symbol.

Let’s consider Stage 2: Preoperational Stage test, or ‘the subject learns to understand images and symbols’ (I took this terminology from Calla H. Knopman’s Measure Your Cat’s IQ.)

Wolfram Chettoh hates being alone. Although he pretends aloofness, wherever I go, he follows. According to cat psychologists, an explanation for this behavior might be that cats see humans as parental figures who take care of their needs. So, Chettoh is just afraid that in case of a sudden urge (to eat, drink, or be cuddled), his foster mum might not be around to satisfy it.
When I’m working at my desk, he’s pretending to sleep nearby. I say ‘pretending’ because he’s actually keeping tabs on me. If I move to another room for just a few minutes, he waits for me to come back; if it takes longer, he joins me: to the kitchen to be taken care of before anything else, or to the bathroom, to sleep on the sink while I’m doing whatever I’m doing. Not to the bedroom, though. The bedroom is off-limits for Chettoh. For years, I let him sleep at the foot of the bed. Then I realized that when I was gone, he immediately relocated to my pillow. Once I got fed up with having to remove a layer of black hair before sleeping, I shut the culprit out.
But what Chettoh hates the most is when I leave home for longer. Having been my devilish pet for twelve years, he learned my habits well. He knows, for example, that on weekdays I’m out for work from about 7:30 AM until 4:00 PM. He’s also aware that on Sunday nights, I usually go out for pizza with friends. So, he gets nervous whenever I don’t follow the usual routine.
For example, if I suddenly change my slippers for a pair of shoes and – in Covid times – put on a face mask, Chettoh rightly understands I’m about to leave. In this case, he waits for me by his food bowl, which happens to be near the main entrance, and demands (with loud, heartbreaking meows) an extra supply of kibbles and cuddles.

Great Sci-Fi Novels 2: Frank Herbert’s ‘Dune’

On By AlessandraIn Books, Reading, Writing

Frank Herbert’s Dune is another famous novel where some backstory is relayed at each chapter’s heading.

The novel’s first installment is much more extended than the Foundation trilogy, so Herbert had more “narrative space” than Asimov to introduce subtle details. 

Each chapter begins with a fictional quote, e.g.: 

“[…] And take the most special care that you locate Muad’Dib in his place: the planet Arrakis. […] Arrakis, the planet known as Dune, is forever his place.” 

(Chapter 1 Heading, from Princess Irulan’s The Manual of Muad’Dib)

The story’s primary location is the arid planet Arrakis, a.k.a. Dune. To paraphrase the ancient Romans: “nomen omen,” the destiny is in the name. In other words, one can already guess that the planet’s environment will be as crucial to the plot as the human characters.

“YUEH […], Wellington […], Stdrd 10,082 — 10,191; medical doctor of the Suk School […]”. 

(Chapter 5 Heading, from Princess Irulan’s Dictionary of Muad’Dib)

Writing about Galactic empires, one must pay attention to the word ‘years.’ The length of the year on Earth (365 days) is not the same as, for example, on Mars (1.88 Earth-years) or Venus (224.7 Earth-days). Dune’s universe extends over numerous worlds, each with its revolution period around the parent star. Thus, to credibly define Dr. Yueh’s age, Herbert had to use an Stdrd (i.e., standard).

“[…] With the Lady Jessica and Arrakis, the Bene Gesserit system of sowing implant-legends through the Missionaria Protectiva came to its full fruition. The wisdom of seeding the known universe with a prophecy pattern for the protection of the B.G. personnel has long been appreciated, but never have we seen a condition-ut-extremis with more ideal mating of person and preparation. […]. ” 

(Chapter 7 Heading, from Princess Irulan’s Analysis: The Arrakeen Crisis)

The Bene Gesserit order is probably what inspired George Lucas when he invented the Jedi order of Star Wars. Like the Jedi Masters, the Bene Gesserit use powerful mental techniques, developed through years of hard training, to engineer Galactic politics according to their plan. For example, one of their purposes is to select the mythical figure known as Kwisatz Haderach genetically. A similar plot device occurs in The Phantom Menace, the first episode of the Star Wars saga. The main storyline has the Jedi Master Qui-Gon Jinn and his apprentice Obi Wan-Kenobi chance upon a boy who might be the “Chosen One.” This is another name for a Galactic Messiah.

“[…] On the first day when Muad’Dib rode through the streets of Arrakeen with his family, some of the people along the way recalled the legends and the prophecy and they ventured to shout: ‘Mahdi!’. But their shout was more a question than a statement, for as yet they could only hope he was the one foretold as the Lisan al-Gaib, the Voice from the Outer World. […]”

(Chapter 13 Heading, from Princess Irulan’s The Manual of Muad’Dib)

The author’s intent is once again to convey the significance of Muad’Dib’s character. The people of Arrakis call him ‘Mahdi,’ a strongly messianic title. Indeed, ‘Mahdi’ isn’t a fantasy name but belongs to a religious figure of Islam. According to some Muslim traditions, the Mahdi will show up to deliver the world from evil and injustice in the Last Days. Throughout history, various individuals have claimed to be or were proclaimed to be the Mahdi. Among them, Muhammad Ahmad, the religious leader who established the Mahdist State in Sudan in the late 19th century and obtained a famous victory over the British in the siege of Khartoum.

ARE ROGUE WORLDS THE ULTIMATE ABODE FOR LIFE?

On By AlessandraIn Extrasolar Planets, S.E.T.I.1 Comment

The search for extraterrestrial life has captivated humanity for centuries. Countless questions arise in our quest to discover if we are alone in the vast universe. The Drake Equation, a mathematical formula introduced by astronomer Frank Drake in 1961, attempts to estimate the number of civilizations within our Milky Way Galaxy. However, recent scientific discoveries have unveiled a new intriguing possibility – rogue worlds. These wandering bodies, expelled from their original solar systems, may hold the potential for harboring life. In this blog post, we will explore the fascinating intersection of the Drake Equation and the enigmatic realm of rogue worlds, exploring the tantalizing notion of life beyond our home planet.

The original form of the equation is the following:

N = R* f(p) n(e) f(i) f(l) f (c) L

• N is the number of civilizations trying to communicate with us right now;

• R* is the rate of star formation in stars per year;

• f(p) is the fraction of those stars which have planetary systems;

• n(e) is the number of Goldilocks (i.e., Earth-type) planets in a planetary system);

• f(l) is the fraction of habitable planets that are inhabited;

• f(i) is the fraction of inhabited planets that possess intelligent technological civilizations;

• f (c) is the fraction of intelligent technological civilizations that choose to emit detectable signals;

• L is the length of time signals will be sent.

The first three factors are astronomical, the fourth and fifth are biological, and the last two factors are social. There are several issues with the equation. Among these:

(1) The uncertainties are large enough for the astronomical factors and increase as one progresses from the astronomical to the biological to the social.

(2) Most factors depend on theoretical insights of star and planet formation, new discoveries about exoplanets, and varying subjective opinions on the evolution of life and intelligence. The presumed longevity of civilization must also be taken into account.

(3) The equation has many hidden assumptions: a uniform star formation rate (SFR) over the Galaxy’s lifetime and a steady state of civilization birth and death. 

(4) No matter what value one chooses for R*, the assumption is always that a habitable planet must have a star. However, rogue worlds (bodies that have been thrown out of their own nascent solar system) wander around the Galaxy unattached to a star.

This last item has recently awakened great interest in the scientific community.

Theoretical calculations (Imagined Life, by James S. Trefil and Michael Summers, 2019) suggest that:

“[…] the number of rogues might be between twice and thousands of times the number of conventional planets. Interstellar space must be littered with them!”

Also, rogue planets need not be uninteresting ice balls with no life and energy. Lacking direct radiation from a star, a world can be heated by the residual power from its formation and the radioactive decay of elements in its interior. If provided with one or more moons, the planet can draw energy from a process known as tidal heating (which is responsible for the subsurface oceans on some of Jupiter and Saturn’s moons).

All in all, rogue planets can be compared to (Imagined Life by James S. Trefil and Michael Summers, 2019):

“[…] houses whose lights have been turned off but whose furnaces are still operating.”

Interestingly, rogue planets had been predicted as early as the 1930s by American horror and S.F. author Howard Phillips Lovecraft.

In his short story: The Haunter of the Dark, he wrote:

“[…] remember Yuggoth, and more distant Shaggai, and the ultimate void of the black planets… […].”

When the planet Pluto had just been discovered by Clyde Tombaugh (1906-97) at Lowell Observatory (Flagstaff, Arizona), he wrote another short story: The Whisperer in Darkness.

Here are a few quotes: 

“[…] Their main immediate abode is a still undiscovered and almost lightless planet at the very edge of our solar system – beyond Neptune and the ninth in distance from the [S]un. It is, as we have inferred, the object mystically hinted at as ‘Yuggoth’ in certain ancient and forbidden writings; […] I would not be surprised if astronomers become sufficiently sensitive to these thought-currents to discover Yuggoth when the Outer Ones wish them to do so. But Yuggoth, of course, is only the stepping-stone. The main body of the beings inhabits strangely organised abysses wholly beyond the utmost reach of any human imagination.”

And also:

“[…] Those wild hills are surely the outpost of a frightful cosmic race – as I doubt all the less since reading that a new ninth planet has been glimpsed beyond Neptune, just as those influences had said it would be glimpsed. Astronomers, with a hideous appropriateness they little suspect, have named this thing ‘Pluto.’ I feel, beyond question, that it is nothing less than nighted Yuggoth […].”

What would life be like on a rogue planet?

According to Imagined Life, by J.S. Trefil and M. Summers:

“It’s dark. Not midnight-on-a-side-street dark, but trapped-in-a-cave dark. And no wonder—there’s no sun in the sky, for this is a rogue world, one that circles no star. There is a moon up there somewhere, but without a source of light for it to reflect, it’s just a darker patch in the sky. Whatever life forms live on this planet had better be able to see in infrared because there’s simply no other light to be had. You’re wearing infrared sensors, fortunately, and you spot a few of these creatures scurrying back to the planet’s subterranean tunnels, where they can bask in the heat emanating from the planet’s interior. […]”

Life on a dark planet has been described by British author Arthur C. Clarke in his 1950 short story: A Walk in the Dark:

“[…] Here at the edge of the Galaxy, the stars were so few and scattered that their light was negligible. […]” 

“[…] Here at this outpost of the Universe, the sky held perhaps a hundred faintly gleaming points of light, as useless as the five ridiculous moons on which no one had ever bothered to land. […]” 

“[…] No one could deny that the tunnels out in the wasteland were rather puzzling, but everyone believed them to be volcanic vents. Though, of course, life often crept into such places. With a shudder, he remembered the giant polyps that had snared the first explorers of Vargon III […]

The Drake Equation is not meant to give a precise answer but to stimulate scientific discussion and exploration. It is based on several factors that affect the likelihood of finding intelligent life, such as the rate of star formation, the fraction of stars with planets, the fraction of planets suitable for life, and the fraction of civilizations that develop radio technology. Each factor is multiplied by the previous one, resulting in the number of detectable civilizations in our galaxy. However, many of these factors are uncertain, and different assumptions can lead to different outcomes. For example, some estimates suggest that there could be millions of civilizations in our Galaxy, while others suggest that we might be the only one.

According to a recent study, under the strictest set of assumptions, where life forms between 4.5 billion and 5.5 billion years after star formation, there are likely between four and 211 civilizations in the Milky Way today capable of communicating with others, with 36 the most likely figure. Another study yielded two main results: an optimistic one and a pessimistic one. In the optimistic situation, the researchers suggested the aforementioned 42,777 communicating extraterrestrial intelligent civilizations (CETIs) with an error margin of plus 267 and minus 369, and they would need to survive 2,000 years on average to communicate with us.

The Drake Equation is a fascinating way to explore the possibilities of extraterrestrial life and communication. It helps us understand what we know and don’t know about our place in the universe. It also inspires us to keep searching for signs of other civilizations and to wonder what they might be like.

Read more about this topic in this post and this other post.

HOW TO CALCULATE YOUR CAT’S IQ

On By AlessandraIn Cats, Wolfram "Morsy" Chettoh1 Comment

Cats’ IQ has long fascinated pet owners and researchers alike. The latest scientific findings shed light on various aspects of feline cleverness, allowing us to appreciate their unique abilities. Measuring cats’ intelligence involves assessing their cognitive abilities and problem-solving skills. One standard marker of cat intelligence is their ability to adapt to new environments and learn from experiences.

I had my cat Chettoh take a challenging test to assess his IQ (which I suspect must be way above the feline average). I found this test in Calla H. Knopman’s book Measure Your Cat’s IQ, which I mentioned in a previous post.

The Cats as Analytical Beings Test comprises four stages, each harder than the earlier one. Depending on the outcome of a given step, a devilish genius like my Chettoh can either improve his entry score (5 points) or subtract from it.

Stage 1: Sensorimotor test, a.k.a. ‘out of sight, out of mind test.’

The aim is to test the cat’s ability to understand object permanence.

According to the book, one must:

“[…] Show the kitty a toy and keep their attention by playing with it. Then hide the toy behind your back or someplace out of sight and see if your cat finds it. Kittens and young children would have no idea what happened to their toys. [However], most adult cats immediately go behind your back to retrieve the toy, wondering what is wrong with you. […]”

Unfortunately, Chettoh doesn’t like to play. One might argue that a fourteen-year-old cat is an elderly cat: of course, he doesn’t want to play. I doubt that’s the problem, though. Chettoh never loved cat toys, not even when I first brought him home on April 24th, 2009, in a shoebox with a punched lid.

Soon, I realized that eating, sleeping, licking his fur, and using the litter took up 98% of his time. Sometimes, he enjoyed a bit of hand-to-hand fight (literally) with his human mom. If I only tried to stroke him, he would become a biting and scratching little panther. This attitude soon earned him a second nickname: Morsy, Italian slang for ‘someone who bites.’

So, I can’t use a toy to assess Chettoh’s sensorimotor prowess. Still, I have another story that serves as a perfect example of his uncommonly analytical mind.

Like many cats, Chettoh occasionally suffers from hairballs. This happens mainly during the shedding season. And the consequences are rather unpleasant: he often barfs, usually in the house’s most hidden and hard-to-reach corners. Trying to solve the problem, I went to a pet shop and bought a medication tube. According to the instructions, the yellowish jam had to be spread over the cat’s food. Only a few small doses would suffice to eliminate the worst hairball symptoms.

Well, it didn’t work. Chettoh became pickier than usual with his food. He refused to eat whenever he smelled the tiniest amount of yellow jam. Out of ideas, I resorted to reading the small printing on the patient information leaflet. “In case of difficult cats,” it said, “the product should be smeared on the animal’s paws.”

At first, this second attempt was a roaring success. But, as often happens, it was too good to be true. Sure, Chettoh gulped all his food, carefully licking every last scrap of medication from his front paws. Also, he stopped throwing up.

However, he soon developed an unquenchable craving for the yellow jam. He began refusing even his favorite food (fish and chicken cakes). All he cared for was a generous amount of that devilish drug on his paws. 

I tried to wean him out of that medicine by gradually reducing the amount I put on his paws and hiding the green tube.

Unfortunately, Chettoh knew the kitchen cabinet where I kept it and waited long hours in front of it, looking sad.

Finally, after long, frustrating weeks, I succeeded.

So, I know the answer to the sensorimotor test. My cat can understand object permanence.