Take Me to Your Leader: Perspectives on Your First Alien Encounter by Neil deGrasse Tyson - 6

There’s no reason Aliens couldn’t run faster than us. Jump higher. Or even fly. A useful power might be to regenerate appendages, as casually depicted in the 1984 indie sci-fi film The Brother from Another Planet . The Alien in that storyline escaped to Earth having been enslaved on his home planet. He was literally an undocumented Alien wandering the streets of New York City, after (coincidentally) crash-landing on Ellis Island I . He otherwise looks convincingly human. A severe leg injury completely heals while he hobbles around, regenerating a new foot. And in the 1997 film Men in Black , starring Will Smith, one of the Aliens on Earth—arms dealer Jack Jeebs—simply regrows his head anytime you shoot it off.

Turns out, all these physiological features already manifest in life on Earth. There’s of course no shortage of animals that can run faster and jump higher than we can. The world’s fastest human, Jamaican sprinter Usain Bolt, would easily be caught and eaten by a half dozen different species of mammal predators. II

Eleven thousand species of birds fly. But we can’t. Meanwhile, a lost claw is not a lost cause for lobsters. They regrow appendages. Same for newts and starfish. III Some planarian flatworms possess stem cells that will even regrow their own head, rendering the guillotine a useless form of capital punishment in their world. So Hollywood Aliens have got nothing on Mother Nature.

Sticking with humans, we’re biologically endowed with five traditional senses, many fewer than Voltaire’s Saturnian and Sirian Aliens. Collectively, these senses serve our need to gather information about our environment—mostly for our survival. In sequence of how far away they can detect things, we get: taste, touch, smell, hearing, and sight. When not invoking our senses for survival, which is most of the time in modern civilization, we divert significant personal resources to please them via food, music, and art. There’s no reason at all for Aliens to share these same five senses. They might wield fewer than we do, or many more. And those senses may be significantly more (or less) acute than ours. But if the evolution of animals on Earth is any indication, the Aliens will have, as a minimum, sight, sexual reproduction, and locomotion. These capabilities proved so useful to survival on Earth that they each evolved in multiple independent ways, across various species. The vertebrate eye, fly eye, spider eye, octopus eye, and bat echolocation (a talent shared by the blind Marvel Comics superhero Daredevil) do not have common evolutionary roots. As for locomotion, millipedes get around town with hundreds of legs, while, of course, the snake manages just fine with no legs at all. And sexual reproduction is rampant in not only the animal and plant kingdoms but also the fungal kingdom.

The large-eyed Alien trope grants them excellent vision. The laws of optics for big eyeballs give you better acuity (higher resolution) as well as excellent vision in dimly lit environments. But, if skulls matter, this power of vision comes at a cost. The human brain is eighty times larger in volume than our eyeballs. If your Alien has huge eyeballs, and if both their eyeballs and their brains reside inside their head, then huge eyeballs leave less room for brains. Animated Disney characters and horses, both with adorably large eyes, suffer the same problem. So too do all the creepy, big-eyed children illustrated by artist Margaret Keane. IV If the Disney queen Elsa from the Frozen film franchise has a human-sized head, then her brain is only ten times the size of her eyeballs. A horse’s brain, half the size of a human brain, is only five times the volume of its two eyeballs. So a big-eyed Alien, who acutely sees its environment, may be stupider than we first estimate, and, like horses, might startle easily.

The Alien in The Brother from Another Planet also had super-duper, hypersensitive hearing. By touching surfaces, he could detect sounds years and even decades after the incident that created them had passed. A spooky, powerful, creative addition that happens to be physically impossible. Sound is a vibrating pulse of energy that moves outward at various speeds, depending on the medium through which it travels. It doesn’t hang around. Actually, it can stay for a short while, but only if the environment allows an echo, itself typically vanishing to nothingness within seconds. V

When you don’t possess a sense that another life-form does, their behavior will, at times, seem peculiar. In what has risen to the status of proverb, but is commonly attributed to the nineteenth-century philosopher Friedrich Nietzsche, we revisit the role of senses in our understanding of objective reality:

And those who were seen dancing were thought to be

Insane by those who could not hear the music.

Nietzsche notwithstanding, as mere humans, we do quite well in the sensory department. To compensate for what we may be missing physiologically, civilization invented the next best thing. It’s called science. Ever since the near-simultaneous discovery of the microscope and telescope in the early 1600s, the number of science senses has grown steadily.

Science senses are stimuli to which human physiology is mostly or entirely oblivious. They’re measurements of our environment. A partial list includes the detection of electromagnetic energy beyond what our retinas see: radio waves, microwaves, infrared, ultraviolet, X-rays, and gamma rays. With high sensitivity, we can detect and measure Earth tremors, magnetic fields, and ionizing radiation. We can measure small changes in Earth’s gravitational field as you ascend an elevator. We can measure the polarization of light. We can decompose light into its component wavelengths using a spectrograph. We can detect sounds far outside the frequency range of human hearing—at both the high and low end. We detect chemicals that you can neither see, nor taste, nor smell—on the level of parts per billion. And in the hospital, we boast a half dozen ways to see inside your body without first cutting you open. So the next time someone at your dinner party boasts of a “sixth sense,” you no longer need to be impressed.

An enviable power for an Alien to possess would be the ability to see any band of light. You’d also want the capacity to tune those wavelengths, otherwise you’d be overwhelmed with visual information, rendering it useless. Imagine walking down the street with those powers. Tune to microwaves and what do you see? For every cell phone conversation the person’s phone would be ablaze with fluctuating light. Anybody using wireless headphones or earbuds? Their Bluetooth technology also uses microwaves. You’d see microwave light coming from the pocketed music player and sparking out of each ear. Key fobs? Every press of a button—to unlock the door, pop the trunk, relock the car—sparks another visible pulse of microwaves, at the key fob itself and at the car. Ubiquitous cell phone towers would be ablaze on the tops of buildings and hills. Know what else uses microwaves? Police radar guns. Aliens with multispectral vision would never get a speeding ticket because they could easily spot the radar well in advance, as a bright source of microwave light from behind the bushes.

Visible light from the Sun, upon being absorbed by Earth’s surface, converts to infrared light and reradiates back into the atmosphere, where it’s trapped by greenhouse gases. With vision tuned to the infrared part of the spectrum, you could watch this happen in real time, while you look upon global warming skeptics who look hopelessly ignorant to you.

While at the dentist, but only after the technician exits the room, you would see bright pulses of X-ray light emanating from that mysterious cone-shaped thing they aim at your teeth and gums. And, as people lie on the beach, exposing their skin to ultraviolet light from the Sun, you would bear witness to these rays as they damage skin cells, first darkening them, ultimately rendering them cancerous.

Perhaps the brightest source of light around us are radio waves. They’re everywhere. Communication satellites, especially the many thousands of SpaceX Starlink satellites that orbit Earth, would be fully visible in the dark of night, slowly crossing the sky. And in spite of most people receiving their TV entertainment via the internet or cable, TV and radio stations still broadcast powerful radio-wave signals via tall antennae. Control towers at airports would be ablaze with light. Airplanes in the sky would be equally ablaze as they communicate with air traffic control. And, as already noted, these are the signals that escape Earth, announcing to the universe who we are and where anybody can find us in the Milky Way.

If you couldn’t tune your bandwidths, your field of view would be overrun with visual noise.

Such powers did not go unnoticed by science fiction writers. In the 1987 reboot Star Trek: The Next Generation , which ran for seven seasons, the character Geordi La Forge wears a VISOR, which is the meta-descriptive acronym for Visual Instrument and Sensory Organ Replacement. He could scan and report on any and all electromagnetic energy in front of him—especially useful when on the deck of a starship navigating the Galaxy. So, tunable multispectral vision would surely be a most-coveted Alien power. Not a weapon of offense, but an extraordinary tool of awareness and surveillance.

Well before Star Trek , however, we had Superman, an Alien with a combination of X-ray and heat vision, first revealed in 1949, 1 eleven years after the comic and character had premiered. Not tunable, but he could definitely see through people, places, and things. He could also use this power of vision to set things on fire. Note that seeing X-rays and the X-ray vision reported for Superman are two different things. If all you could see were X-rays, and nothing around you emitted them, then the scene would be completely dark. If, however, your eyeballs emitted X-rays, your object of interest (situated behind walls, inside boxes, etc.) would need to reflect them back for you to know anything about what you’re looking at. Remember that a medical X-ray machine not only generates X-rays but uses a detector on the other side of the enclosure to see which X-rays passed through and which got absorbed by the target, be it a package for delivery, or your body parts.

Superman’s ability to heat things would, in 1960, be separated from his X-ray vision 2 and derive from his ability to concentrate other bands of electromagnetic energy on his target. Since X-rays pass through most common objects, they make a poor candidate to concentrate energy. Infrared would work well in that capacity. It’s absorbed by most things, allowing heat energy to accumulate, ultimately igniting the target.

Not until the Golden Age of Islam, a millennium ago, did anybody figure out that sight was a passive phenomenon. VI When you look at anything, even when you look hard at it, you’re simply waiting for light to reach your retina. Those who claim they can “feel” when someone stares at them can never reproduce that claim in controlled laboratory settings. This presumed power of vision nonetheless made it into all manner of legends and mythology. Most famous, perhaps, is Medusa, an Earth Alien if there ever was one. Apart from her snake hair, if she simply looked at you, you’d turn to stone. Hero Perseus slayed her with his sword by taking aim via her reflection on the inner surface of his polished shield. Apparently, reflections neutralize the stone-stare. These are the stories that get written when you have no understanding of physics.

One can speculate whether Superman’s inner physiology is also superhuman. Like dogs, he can hear sound outside the normal human range of frequencies. But how do his inner organs function? This subject was addressed on a StarTalk podcast in response to a question submitted by a listener. 3 If, whatever humans have, Superman has more of it, then he might have super digestion, enabled by super bacteria in his gut. His bacteria would generate super waste gases—especially hydrogen sulfide (H 2 S) and methane (CH 4 ). These enhanced effluences would be noticed immediately by anyone standing near him, especially in a closed elevator. But therein lies two new superpowers. Hydrogen sulfide is smelly and actually deadly, even in small concentrations, giving literal meaning to the phrase “silent but deadly.” It’s one of the few gases that we can smell at a much lower concentration than what will kill you. Evolutionarily, that’s why farts smell bad. Anybody who took pleasure in flatulence-based aromas (eau de fart) would be summarily removed from the gene pool. So that’s one superpower: he could kill everyone in the elevator if he chose to.

But also, methane is highly flammable. If you must know what that looks like chemically:

CH 4 + 2 O 2 CO 2 + 2 H 2 O + Energy

Though rife with risk and hazard, those who attempted to light farts with matches or a cigarette lighter at summer camp were performing an actual science experiment. Combine the methane in Superman’s farts with his infrared vision, and he could roll down his drawers, aim his butt at a target, let one loose, and direct his infrared vision at the gas stream, creating a veritable flamethrower. Surely occasions abound in crime fighting where a butt flamethrower would be useful, but shooting flames from your eyeballs would be simpler and less humiliating.

Is any of this different from a fire-breathing dragon? Perhaps not. Cows, which all have active digestive systems, utilizing multiple stomachs, burp and fart more than two hundred pounds of methane per year, per cow. 4 Many farms today harness cow methane and burn it for heat and electricity in their barns. 5 Methane is also a potent greenhouse gas, nearly thirty times as absorptive of infrared energy as carbon dioxide. So if you see a cow-Alien descend from a spaceship, keep your distance, front and back. If they’re also equipped with Superman’s infrared vision, the creature could ignite flames at both ends.

A persistently portrayed feature of Aliens is their ability to communicate with one another telepathically. Why not? Our thoughts are nothing more than neurochemical and electromagnetic impulses within our brain. From afar you can’t know the neurochemistry, but the electromagnetic activity creates a field both inside and outside your skull, which is detectable and, in principle, decipherable. There’s otherwise no secret undiscovered means of projecting thoughts or information from one being to another.

Here’s why we can make that claim: to communicate, or to simply detect any signal at all, requires a change in the configuration or energy state of a system. Consider that, in 2016, astrophysicists figured out how to detect ripples in the fabric of space-time 6 caused by two colliding black holes in a distant galaxy. After traveling at the speed of light for billions of years, the energy of those waves that washed over Earth was small enough to require a measurement on the scale of one one-hundredth the diameter of a proton—a triumph of relativity and quantum physics. To achieve that level of precision requires that you account for all other possible causes of vibrations in the experiment. And they did. The lesson? If anybody is walking around with actual extrasensory perception (ESP), be they human or Alien, it would not escape our detectors, empowering physicists with means to eavesdrop on telepathic secrets.

A spooky possibility, however, would be if the Aliens project electromagnetic signals into our brains that we think are our own thoughts. This trick is famously used by Jedi in the Star Wars franchise. Works especially well when you’re not otherwise authorized to walk past a guard on duty. You wield your authority with a gentle wave of your hand. The guard mindlessly agrees with you and lets you pass. To control someone’s thoughts is to control their behavior, which would signal the end of free will. If Aliens wielded that power over us then it’s game over.

Consider, however, that metal can shield electromagnetic fields. Any cavity enclosed by metal is called a Faraday Cage and will protect all that’s inside from electromagnetic intrusions. Lightning itself cannot even penetrate. The military builds such rooms and calls them SCIFs, for Sensitive Compartmented Information Facilities. That’s where they share secrets that can’t be externally bugged by any form of electronics. What this means is that all the people we know, or have read about, who wear “tinfoil” hats VII may be our saviors when confronted with mind-control Aliens.

Some Aliens like to disappear and reappear at will—popping in and out of existence. A highly improbable green Alien named “the Great Gazoo” visited Fred Flintstone and Barney Rubble in the last season of the 1960s prime-time Stone Age cartoon The Flintstones. Gazoo had the power to appear and disappear with the snap of his finger. As you might have guessed, the show had just “jumped the shark.” VIII Even though Gazoo was not real, it doesn’t change the physics of the situation: you cannot simply pop into and out of existence without a trace. When matter disappears, it becomes energy, not nothing.

You can’t cheat E = mc 2 .

One could, however, access a wormhole through space-time—stepping in and out of your location without making a formal entrance or exit and without leaving a trace. We know how to make wormholes, only we can’t. We don’t have the right ingredients. Wormholes require a substance that may or may not exist in the universe, carrying negative gravity, allowing you to pry open the fabric of space-time. Regular gravity, on the other hand, wants to collapse space-time onto itself. The humanoid superheroes Thor and Superman are both Aliens. And they both arrived on Earth via wormholes, IX so we’re good there.

The physics of invisibility remains a fascinating frontier of quantum optics. The challenge is to get a photon of light from behind you, which you otherwise would have blocked, to travel around your body and come out the other side, continuing on its way as if you weren’t there at all. In the 2002 James Bond film Die Another Day , starring Daniel Craig, his Aston Martin Vanquish employed technology, at the press of a button, to simply disappear from view. It uses physics, rather than the magic required for Harry Potter’s invisibility cloak in the book and film storylines. In both cases, however, you have not physically disappeared. You’re still there. It’s just that nobody can see you.

This distinction is not a simple matter of semantics. A clear window is transparent because visible light photons from one side emerge coherently on the other side. The glass has disappeared from view, even though it’s still there. Conversely, most household glass blocks ultraviolet light. So if we could tune our eyes to that band of light, transparent windows would all of a sudden become opaque. One of the factors that delayed the creation of lenses for microscopes and telescopes was the technological challenge of manufacturing perfectly clear glass. Hence the prevalence of crystal balls as transparent objects in storytelling and even in ancient reference to planetary orbits, each embedded in a “crystalline sphere,” allowing you to see through them all, to the outermost layer of “fixed” stars.

The coolest thing ever would be if Aliens occupied more spatial dimensions than we do. We are three-dimensional creatures. Nothing to stop an Alien from living in four or five or more dimensions. If they never deigned to pass through our measly three dimensions, we would never know they were there. But if they did, they would appear out of nowhere, and we would only be able to detect three of the Aliens’ higher dimensions of existence. In a simple example, imagine we were 2D creatures living in, and constrained to, a flat plane. We would know squares, but have no concept of a cube, which requires an extra dimension that lives outside of our 2D awareness. If an aligned cube sank through our world, all we would see are squares. If a sphere passed through our 2D world, all we would see are circles.

Another feature of higher-dimensional Aliens would be their ability to see all the organs inside your body. Actually, they would be able to see inside of any 3D enclosure. This power comes not from some magic X-ray vision. It’s a simple property of your existence in a higher spatial dimension. If you first draw a square on a sheet of paper, and then imprison a stick figure within its border, nobody in the universe of your 2D paper would know about your stick figure. For them, no sight line has access to the square’s contents. Yet what’s inside is completely visible to you, a high-and-mighty 3D person, relative to all the flat residents within the paper. Upping this analogy by one dimension, everything that sits within a 3D enclosure, in a 3D world, is completely visible to all 4D beings. If we had access to this fourth spatial dimension, privacy laws would look very different. More importantly, medical surgery would be transformed, granting the 4D surgeon direct access to your innards without cutting you open.

These higher-dimensional Aliens could, in principle, disappear from view by simply sliding out of our three dimensions. But this doesn’t make them invisible. They’ve simply exited your space. While passing through our dimensions, we would most definitely detect their existence even if we can’t envision their full form in their higher-dimensional world.

In summary, Aliens that disappear from view—no problem. Aliens that step back and forth across wormholes—no problem. Aliens that disappear without a trace within our three dimensions? Now you’re violating universal laws of physics.

The closest example we might imagine to being transported into another dimension is a fish, living its whole life underwater. It suddenly gets yanked from the sea with a hook in its mouth, grabbed by human hands, stared at briefly, judged to be too small, then tossed back, to live another day and tell its friends what just happened. No matter how that incident gets told, fellow fish friends will never believe it, even though the fish never left three dimensions. Now imagine the challenge of describing an actual higher-dimensional excursion. 7

People who say they saw Heaven and try to describe it usually have a hard time doing so. But if a prerequisite for seeing Heaven is you being dead, then why should anybody believe you? Unless you saw Heaven while you were temporarily dead and doctors brought you back to life. If so, then modern medicine thwarted the will of your God. Seems to me, that’s a story worth hearing too.

Fanciful dreams are also a challenge to describe with any precision. Maybe it’s our mind routinely accessing other dimensions. Or, more likely, it’s just neurochemistry having fun.

One TV Alien deserves special attention. In spite of mediocre reviews from critics, the sitcom Out of This World ran for four seasons, X beginning in 1987. It featured a half-Alien teenage girl, Evie Garland, born of a human woman and a highly humanoid male Alien from the planet Antareus. His spaceship crashed on Earth, after which he met, married, and mated. He was later called back to his home planet to fight in a war, leaving behind his wife and daughter. One of Evie’s several Alien abilities, which first manifested when she turned thirteen, is the power to stop time by simply touching together the tips of her two index fingers. Upon doing so, she can then move and maneuver within the scene, both manufacturing and mending the sitcom-havoc required of the plotlines.

In Albert Einstein’s theory of relativity, the flow of time is relative and can be influenced by your motion through space or by the strength of gravitational fields. This cosmic fact, as with other laws and principles of physics, is not “just a theory,” but has been verified across the Galaxy and across the universe.

There’s no reason, in principle, why advanced Aliens could not harness these facts-of-physics into a superpower. If our teen Alien managed to subject everything around her to an extremely high gravitational field, such as what one finds in the vicinity of a black hole, then her perceived passage of time would feel normal, while everything else would have slowed to a near-standstill. No, she can’t stop time completely, but she can make it pass arbitrarily slowly for all around her. The problem is that if you find yourself in the same place at the same time as someone else, it means your worldlines intersect. “Worldline” is the slick and authentic term that describes your life’s trajectory through space and time. Where worldlines join, every person, place, and thing at the point of intersection will experience the same flow of time. So the closer Evie approached others, frozen in the scene, the slower her time would tick as well. Can’t get around that fact. But I’m otherwise happy to write Out of This World a hall pass for thinking up this novel and entertaining Alien power.

Evie also wields powers of telekinesis—the ability to move objects at will, without physically touching them. There’s no end of such portrayals in movies that feature very, very, very smart people, even though there’s no biological reason whatsoever for such powers. Apparently, we’re not content with just really smart people solving really hard problems. In both the 1996 film Phenomenon , starring John Travolta, and in the 2014 film Lucy , starring Scarlett Johansson, for example, the main character becomes superintelligent and also telekinetic. In Phenomenon , the main character could also sense ground stress that precedes earthquakes—an admittedly useful power of perception.

When cinematic smart people wield the ability to move stuff, it’s often with finger gestures controlled by their mind. Of course, we perform telekinesis in physics all the time. It requires a configuration of matter that can act on the object you want to control, and it has nothing to do with your brain. In physics each of the forces creates a field that can set matter into motion under the right conditions. A familiar example comes from electromagnetic fields. They’re how magnets manage to move things. And if we could manufacture and manipulate mini–black holes, we could move things around in our lives gravitationally.

Ordinary matter is neutral, possessing a mixed and balanced number of negative charged electrons and positive charged protons. But if you managed to segregate some of the object’s electrons over to one side, you could then adjust the charges within your finger to display an excess of protons toward the object, thus attracting it. Want to push it away? Show it an excess of electrons.

Two problems, however: (1) Your satchel of black holes would all merge into one larger black hole. That larger black hole will then consume you. That even larger black hole will then systematically consume all of Earth. That would be bad. And (2) electrons are necessary ingredients in all molecules. They’re what enable atoms to stick together and exhibit the myriad properties that make life possible. To pull electrons away from their jobs is to ionize the molecules, undermining the integrity and identity of the molecules themselves. That’s why ionizing radiation is harmful and ultimately lethal.

Ignoring those complications, teen-Alien telekinesis is clearly a useful power to possess, especially when navigating the complex and stressful social life of high school.