From the September 2013 issue

Night sweats

Astronomers must overcome the ancient human fear of darkness.
By | Published: September 23, 2013 | Last updated on May 18, 2023
Autumn brings ever-expanding night. For many, this is not pleasant. Halloween unites classic darkness terrors with deliberate spookiness. And November in most of the United States and Canada is when suddenly bare, twisted branches and stronger gusts create a mood of icy menace. Outdoors, life’s colors and scents vanish. Even the birds pack it up and flee.

Most astronomers welcome these expanding eyepiece opportunities — especially when our sister galaxy, Andromeda, is overhead and we get our first peek at the returning brilliance of Orion and his friends. But even backyard stargazers sometimes look over their shoulders when cold winds howl. It can be creepy out there.

We glorify space travel and the notion of human colonies on other worlds. But astronauts will tell you: The starry realm is not benign. Death lurks beyond the crew compartment’s metal walls.

An unprotected person accidentally hurled out a spaceship’s airlock, that common sci-fi scene, would stay conscious for no more than 20 seconds. Composed mostly of water, a human body would quickly revert to the universe’s commonest form of H2O — a block of ice. If subsequently struck by a meteoroid, the body would shatter into pieces, perhaps dividing itself along internal fault structures defined by organs. If the experience occurred near Jupiter, radiation would sterilize all living tissue. Near white dwarfs or neutron stars, tidal forces would rip a skeleton to pieces.
In Earth’s vicinity, the side of the unprotected astronaut’s body facing sunward would rapidly heat like a microwave to some 250° Fahrenheit (120° Celsius), above water’s boiling point. Searing solar ultraviolet rays — including the fearsome UVC never experienced on Earth’s surface — would deliver a painful burn in 20 seconds. A three-minute exposure would cook skin to carbon. Meanwhile, being in a vacuum would nullify one’s health insurance. The pressure differential would force body gases outward; eardrums and eyeballs would pop.

We are creatures of Earth. We carry our planet inside us, fashioned as we are of terrestrial components like oxygen, which alone constitutes 65 percent of our bodies by mass. The more typical stuff of the cosmos — hydrogen and helium — offers no nourishment or support on its own. Fear of the sky thus has a rational basis.


For some reason, children below the age of 2 are rarely afraid of the dark. But they soon make up for this slow start, since it eventually afflicts a majority of kids. If severe enough, a fear is a “phobia,” and if the enemy is darkness, the condition is variously called nyctophobia (from the Greek word for night), achluophobia, scotophobia, or lygophobia. The only phobia with four different names, it afflicts 11 percent of U.S. adults, according to the National Institute of Mental Health. It edges out acrophobia (fear of heights) but, in prevalence, ranks below fear of public speaking (glossophobia), fear of death (necrophobia), and fear of spiders (arachnophobia). I’m not sure where fear of dropping an expensive eyepiece fits in.

For kids, it’s not the actual dark that scares them, but its unseen terrors. Ghosts don’t emerge until nightfall, and that shirt slung over a chair surrenders its monster shape only with the dawn. Even many non-phobic adults retain a lifelong nocturnal discomfort. The cause? Well, most ancient cultures feared darkness because of tigers and such, since these predators often boast superior low-light vision. They have the edge after nightfall.

The strange netherworld of dreams doesn’t help. Despite modern “dream labs” and sleep experiments, the little we know is more mystifying than clarifying. No one can explain why dreams get longer as night passes or why early dreams relate to recent events while later ones tend to be more surreal and mysterious in content.

Beyond the psychological explanations, might night sweats stem from actual dangers posed by the starry canopy? Do we harbor genetic memories of celestial cataclysms like meteoric destruction? Probably not. The sky has rarely been a source of injury. Only one person in recorded history was definitely struck by a meteorite, and that was by day. In Sylacauga, Alabama, Ann Hodges suffered a bruised thigh in 1954 after a chondrite came through her roof and ricocheted off a radio. Many others (in 1992 and in 1996, for example) have had close calls when meteorites plowed into their lawns just as they walked by — again, all by day.

So, away from city lights, the nocturnal realm is generally friendly, with many rural meadows filled with nothing more menacing than garden-destroying deer. A nightly stroll under benignly wheeling stars is a low-risk activity. Indeed, we astronomers should perhaps quote Shakespeare. It was he, in Romeo and Juliet, who foresaw a time when “all the world will be in love with night. And pay no worship to the garish sun.”
So let the darkness blossom. Nyctophobia begone!