Randall Munroe Quotes

But I’ve never seen the Icarus story as a lesson about the limitations of humans. I see it as a lesson about the limitations of wax as an adhesive.

Take wrong turns. Talk to strangers. Open unmarked doors. And if you see a group of people in a field, go find out what they are doing. Do things without always knowing how they'll turn out. You're curious and smart and bored, and all you see is the choice between working hard and slacking off. There are so many adventures that you miss because you're waiting to think of a plan. To find them, look for tiny interesting choices. And remember that you are always making up the future as you go.

There’s no material safety data sheet for astatine. If there were, it would just be the word “NO” scrawled over and over in charred blood.

The role of gender in society is the most complicated thing I’ve ever spent a lot of time learning about, and I’ve spent a lot of time learning about quantum mechanics.

Your plane would fly pretty well, except it would be on fire the whole time, and then it would stop flying, and then stop being a plane.

It’s not the fall that kills you, it’s the sudden stop at the end.

They say there are no stupid questions. That’s obviously wrong; I think my question about hard and soft things, for example, is pretty stupid. But it turns out that trying to thoroughly answer a stupid question can take you to some pretty interesting places.

Remember: I am a cartoonist. If you follow my advice on safety around nuclear materials, you probably deserve whatever happens to you.

I got in touch with a friend of mine who works at a research reactor, and asked him what he thought would happen to someone who tried to swim in their radiation containment pool. “In our reactor?” He thought about it for a moment. “You’d die pretty quickly, before reaching the water, from gunshot wounds.

I can't remember where I heard this, but someone once said that defending a position by citing free speech is sort of the ultimate concession; you're saying that the most compelling thing you can say for your position is that it's not literally illegal to express.

Things are rarely just crazy enough to work, but they're frequently just crazy enough to fail hilariously.

A world of random soul mates would be a lonely one. Let’s hope that’s not what we live in.

Maybe civilization will collapse, we’ll all succumb to disease and famine, and the last of us will be eaten by cats. Maybe we’ll all be killed by nanobots hours after you read this sentence. There’s no way to know.

The universe is probably littered with the one-planet graves of cultures which made the sensible economic decision that there's no good reason to go into space - each discovered, studied, and remembered by the ones who made the irrational decision.

I like it when things catch fire and explode, which means I do not have your best interests in mind.

Sometimes I mistake this for a universe that cares.

Do not try any of this at home. The author of this book is an Internet cartoonist, not a health or safety expert. He likes it when things catch fire or explode, which means he does not have your best interests in mind. The publisher and the author disclaim responsibility for any adverse effects resulting, directly or indirectly, from information contained in this book.

A million people can call the mountains a fiction, yet it need not trouble you as you stand atop them.

Space is about 100 kilometers away. That’s far away—I wouldn’t want to climb a ladder to get there—but it isn’t that far away. If you’re in Sacramento, Seattle, Canberra, Kolkata, Hyderabad, Phnom Penh, Cairo, Beijing, central Japan, central Sri Lanka, or Portland, space is closer than the sea.

The US isn’t a perfect model of the world,

A. Nearly everyone would die. Then things would get interesting.

If humans escape the solar system and outlive the Sun, our descendants may someday live on one of these planets. Atoms from Times Square, cycled through the heart of the Sun, will form our new bodies. One day, either we will all be dead, or we will all be New Yorkers.

Think of the elements as dangerous, radioactive, short-lived Pokémon.

The explosion would be just the right size to maximize the amount of paperwork your lab would face. If the explosion were smaller, you could potentially cover it up. If it were larger, there would be no one left in the city to submit paperwork to.

So Yoda sounds like our best bet as an energy source. But with world electricity consumption pushing 2 terawatts, it would take a hundred million Yodas to meet our demands. All things considered, switching to Yoda power probably isn't worth the trouble — though it would definitely be green.

If you set out a cup of warm water on Mars, it’ll try to boil, freeze, and sublimate, practically all at once. Water on Mars seems to want to be in any state except liquid.

Sure, we seem like we’ve taken over the planet, but if I had to bet on which one of us would still be around in a million years—primates, computers, or ants—I know who I’d pick.

Whatever happened to our dreams? The infinite possibilities each day holds should stagger the mind. The sheer number of experiences I could have is uncountable, breathtaking, and I'm sitting here refreshing my inbox. We live trapped in loops, reliving a few days over and over, and we envision only a handful of paths laid out ahead of us. We see the same things each day, we respond the same way, we think the same thoughts, each day a slight variation on the last, every moment smoothly following the gentle curves of societal norms. We act like if we just get through today, tomorrow our dreams will come back to us. And no, I don't have all the answers. I don't know how to jolt myself into seeing what each moment could become. But I do know one thing: the solution doesn't involve watering down my every little idea and creative impulse for the sake of someday easing my fit into a mold. It doesn't involve tempering my life to better fit someone's expectations. It doesn't involve constantly holding back for fear of shaking things up. This is very important, so I want to say it as clearly as I can: FUCK. THAT. SHIT.

The lesson: If the optimist says the glass is half full, and the pessimist says the glass is half empty, the physicist ducks.

Physics doesn’t care if your question is weird. It just gives you the answer, without judging.

Horned lizards shoot jets of blood from their eyes for distances of up to 5 feet. I don’t know why they do this because whenever I reach the phrase “shoot jets of blood from their eyes” in an article I just stop there and stare at it until I need to lie down.

By choosing the right words, you can take an idea that's happening in your head and try to make an idea like it happen in someone else's. That's what's happening right now.

Take wrong turns. Talk to strangers. Open unmarked doors. And if you see a group of people in a field, go find out what they are doing. Do things without always knowing how they’ll turn out.

It makes me happy that an arm of the US government has, in some official capacity, issued an opinion on the subject of firing nuclear missiles at hurricanes.

We don’t know what astatine looks like, because, as Lowe put it, “that stuff just doesn’t want to exist.” It’s so radioactive (with a half-life measured in hours) that any large piece of it would be quickly vaporized by its own heat. Chemists suspect that it has a black surface, but no one really knows. There’s no material safety data sheet for astatine. If there were, it would just be the word “NO” scrawled over and over in charred blood.

I'm not sure why we romanticize 'young love,' or love in general...It just leads to the idea that either your love is pure, perfect and eternal, and you are storybook-compatible in every way with no problems, or you're LYING when you say 'I love you.

If you liked it, then you should have moved a mass inside its Roche limit.

There’s no nondestructive test for indestructibility.

Sometimes it’s nice not to destroy the world for a change.

Lastly, we need to know the strength of gravity on Dagobah. Here, I figure I’m stuck, because while sci-fi fans are obsessive, it’s not like there’s gonna be a catalog of minor geophysical characteristics for every planet visited in Star Wars. Right? Nope. I’ve underestimated the fandom. Wookieepeedia has just such a catalog,

A 1-watt laser is an extremely dangerous thing. It’s not just powerful enough to blind you—it’s capable of burning skin and setting things on fire. Obviously, they’re not legal for consumer purchase in the US. Just kidding! You can pick one up for $300. Just do a search for “1-watt handheld laser.” So, suppose we spend the $2 trillion to buy 1-watt green lasers for everyone. (Memo to presidential candidates: This policy would win my vote.)

In the Clarendon Library at Oxford University sits a battery-powered bell that has been ringing since the year 1840. The bell “rings” so quietly it’s almost inaudible, using only a tiny amount of charge with every motion of the clapper. Nobody knows exactly what kind of batteries it uses because nobody wants to take it apart to figure it out.

What if every day, every human had a 1 percent chance of being turned into a turkey, and every turkey had a 1 percent chance of being turned into a human?

I mean, I guess it's just me who argues that; but I'm very vocal.

In conclusion, if the Sun went out, we would see a variety of benefits across many areas of our lives. Are there any downsides to this scenario? We would all freeze and die.

Q. Is it possible to build a jetpack using downward-firing machine guns? —Rob B A. I WAS SORT OF surprised to find that the answer was yes! But to really do it right, you’ll want to talk to the Russians.

For starters, would your soul mate even still be alive? A hundred billion or so humans have ever lived, but only seven billion are alive now (which gives the human condition a 93 percent mortality rate). If we were all paired up at random, 90 percent of our soul mates would be long dead.

There’s a thing about being alone and there’s a thing about being lonely, and they’re two different things.

This is a completely ridiculous suggestion, so it should come as no surprise that it was studied by the US government during the Cold War.

A magnitude 15 earthquake would involve the release of almost 1032 joules of energy, which is roughly the gravitational binding energy of the Earth. To put it another way, the Death Star caused a magnitude 15 earthquake on Alderaan.

THEY SAY LIGHTNING NEVER strikes in the same place twice. “They” are wrong. From an evolutionary perspective, it’s a little surprising that this saying has survived; you’d think that people who believed it would have been gradually filtered out of the living population.

IF YOU WANT TO transfer a few hundred gigabytes of data, it’s generally faster to FedEx a hard drive than to send the files over the Internet. This isn’t a new idea—it’s often dubbed “SneakerNet”—and it’s even how Google transfers large amounts of data internally.

If we divide up the world’s land area evenly, there’s enough room for each of us to have a little over 2 hectares each, with the nearest person 77 meters away.

It's weird how I am constantly surprised by the passage of time when it's literally the most predictable thing in the Universe.

You may actually receive a lower dose of radiation treading water in a spent fuel pool than walking around on the street.

This would be something never before seen in the history of the universe: an underground shooting star.

A darkened Sun would liberate us from the parsnip threat.

I still don’t know whether there are more hard or soft things in the world,

Red Delicious apples, whose misleading name is a travesty.

There were no earthworms in New England when the European colonists arrived.

Do not build the seventh row.

As far as I know, this steak question originally came up in a lengthy 4chan thread, which quickly disintegrated into poorly informed physics tirades intermixed with homophobic slurs. There was no clear conclusion.

But what about gender and sexual orientation? And culture? And language? We could keep using demographics to try to narrow things down further, but we would be drifting away from the idea of a random soulmate. In our scenario, you wouldn’t know anything about who your soulmate was until you looked into their eyes. Everybody would have only one orientation: towards their soulmate.

I have never seen a work of fiction so perfectly capture the out-of-nowhere shock of discovering that you've just bricked something important because you didn't pay enough attention to a loose wire.

For a small smartphone charger, if it’s not warm to the touch, it’s using less than a penny a year. This is true of almost any powered device.1

Self-fertilization is a risky strategy, which is why sex is so popular among large and complex organisms.

The Mars rover Curiosity, for example, is powered by the heat from a chunk of plutonium it carries in a container on the end of a stick.

Even calling DNA “source code” sells it short—compared to DNA, our most complex programming projects are like pocket calculators.

Eventually, they give up, and the unexplained meteorological phenomenon is simply called a “dubstep storm,” because—in the words of one researcher—“It had one hell of a drop.

However, the tests still suggest that nuclear weapons probably don’t make great bottle openers.

Without us, Earth’s geology will grind on. Winds and rain and blowing sand will dissolve and bury the artifacts of our civilization. Human-caused climate change will probably delay the start of the next glaciation, but we haven’t ended the cycle of ice ages. Eventually, the glaciers will advance again. A million years from now, few human artifacts will remain.

That’s why I don’t like making fun of people for admitting they don’t know something or never learned how to do something. Because if you do that, all it does is teach them not to tell you when they’re learning something . . . and you miss out on the fun.

In fact, humans on Titan could fly by muscle power. A human in a hang glider could comfortably take off and cruise around powered by oversized swim-flipper boots—or even take off by flapping artificial wings. The power requirements are minimal—it would probably take no more effort than walking.

GPS timing is incredibly precise; of all the problems in engineering, it’s one of the only ones in which engineers have been forced to include both special and general relativity in their calculations.

X-Plane tells us that flight on Mars is difficult, but not impossible. NASA knows this, and has considered surveying Mars by airplane. The tricky thing is that with so little atmosphere, to get any lift, you have to go fast.

I really love that we can ask physics ridiculous questions like, “What kind of gas mileage would my house get on the highway?” and physics has to answer us.

To put it another way, the Death Star caused a magnitude 15 earthquake on Alderaan.

That’s if everything goes as planned.

two magnitude 9+ earthquakes this century both altered the length of the day by a tiny fraction of a second.

Introverts understand; the loneliest human in history was just happy to have a few minutes of peace and quiet.

the Curiosity rover is working so hard to find evidence of water, so I figured we could make things easier for it.

I like doing math that involves measuring the lengths of numbers written out on the page (which is really just a way of loosely estimating log10x). It works, but it feels so wrong.

But this is where it gets weird. The mole planet would be a giant sphere of meat.

Removing Japan would also have a big effect on ocean currents.

Hello! This is a book of bad ideas.

if you mention how many nuclear weapons you have, you can convince them to give you a discount.

This plan has some flaws. It destroys the Earth, yes, but it’s also unnecessarily inefficient.

Hockey players can also brace pretty hard against the ice. A player skating at full speed can stop in the space of a few meters, which means the force they’re exerting on the ice is pretty substantial. (It also suggests that if you started to slowly rotate a hockey rink, it could tilt up to 50 degrees before the players would all slide to one end. Clearly, experiments are needed to confirm this.)

If you were standing in the path of the beam, you would obviously die pretty quickly. You wouldn't really die of anything, in the traditional sense. You would just stop being biology and start being physics.

While researching this answer, I managed to lock up my copy of Mathematica several times on balloon-related differential equations, and subsequently got my IP address banned from Wolfram|Alpha for making too many requests. The ban-appeal form asked me to explain what task I was performing that necessitated so many queries. I wrote, “Calculating how many rental helium tanks you’d have to carry with you in order to inflate a balloon large enough to act as a parachute and slow your fall from a jet aircraft.” Sorry, Wolfram.

As Tim Minchin put it in his song “If I Didn’t Have You”: Your love is one in a million; You couldn’t buy it at any price. But of the 9.999 hundred thousand other loves, Statistically, some of them would be equally nice.

Here’s a question to give you a sense of scale. Which of the following would be brighter, in terms of the amount of energy delivered to your retina: A supernova, seen from as far away as the Sun is from the Earth, or the detonation of a hydrogen bomb pressed against your eyeball?

To put that in perspective, it takes about five milliseconds for the fastest nerve impulse to travel the length of the arm. That means that when your arm is still rotating toward the correct position, the signal to release the ball is already at your wrist. In terms of timing, this is like a drummer dropping a drumstick from the tenth story and hitting a drum on the ground on the correct beat.

DISCLAIMER Do not try any of this at home. The author of this book is an Internet cartoonist, not a health or safety expert. He likes it when things catch fire or explode, which means he does not have your best interests in mind.

Given all the stress and pressure, some people would fake it. They’d want to join the club, so they’d get together with another lonely person and stage a fake soul mate encounter. They’d marry, hide their relationship problems, and struggle to present a happy face to their friends and family.

One day, either we will all be dead, or we will all be New Yorkers.

Your love is one in a million; You couldn’t buy it at any price. But of the 9.999 hundred thousand other loves, Statistically, some of them would be equally nice.

A child from a parent who self-fertilized would be like a clone of the parent with severe genetic damage.

In a billion years, Earth will become a second Venus.

The amount of power in question, 700 watts, is about a horsepower, so if you want to boil tea in two minutes, you’ll need at least one horse to stir it hard enough.

Centuries from now, deep in concrete vaults, the light from our most toxic waste will still be shining.

Magnitude -15 A drifting mote of dust coming to rest on a table Sometimes it’s nice not to destroy the world for a change.

As comedian Ron White said about hurricanes, “It’s not that the wind is blowing, it’s what the wind is blowing.

Actually, what I’m confused about is how.

the ocean is colder than space.

* If you drink all of someone’s blood, there’s a 100 percent chance that they’ll die.

Trees make babies by dropping tiny wooden tree eggs on the ground.

what year did a single typical desktop computer surpass the combined processing power of humanity? 1994.

things considered, switching to Yoda power probably isn’t worth the trouble—though it would definitely be green.

On one hand, humans and computers do very different types of thinking, so comparing them is like comparing apples and oranges. On the other hand, apples are better

From 1960 into the 21st century, Pennsylvania has voted for five different people named Bob Casey

High up in the North in the land called Svithjod, there stands a rock. It is a hundred miles high and a hundred miles wide. Once every thousand years a little bird comes to this rock to sharpen its beak. When the rock has thus been worn away, then a single day of eternity will have gone by. —Hendrik Willem Van Loon

To see what Times Square looked like before a city was there, we turn to a remarkable project called Welikia, which grew out of a smaller project called Mannahatta. The Welikia project has produced a detailed ecological map of the landscape in New York City at the time of the arrival of Europeans. The interactive map, available online at welikia.org, is a fantastic snapshot of a different New York. In 1609, the island of Manhattan was part of a landscape of rolling hills, marshes, woodlands, lakes, and rivers.

There are hopes that carbon nanotube-based materials could provide the required strength—adding this to the long list of engineering problems that can be waved away by tacking on the prefix “nano-.

Every night, around midnight GMT, the Sun sets on the Cayman Islands, and doesn’t rise over the British Indian Ocean Territory until after 1:00 a.m. For that hour, the little Pitcairn Islands in the South Pacific are the only British territory in the Sun. The Pitcairn Islands have a population of a few dozen people, the descendants of the mutineers from the HMS Bounty. The islands became notorious in 2004 when a third of the adult male population, including the mayor, were convicted of child sexual abuse. As awful as the islands may be, they remain part of the British Empire, and unless they’re kicked out, the two-century-long British daylight will continue.

Cheaper trade: Time zones make trade more expensive; it’s harder to do business with someone if their office hours don’t overlap with yours. If the Sun went out, it would eliminate the need for time zones, allowing us to switch to UTC and give a boost to the global economy.

The official record for the fastest manmade object is the Helios 2 probe, which reached about 70 km/s in a close swing around the Sun. But it’s possible the actual holder of that title is a two-ton metal manhole cover. The cover sat atop a shaft at an underground nuclear test site operated by Los Alamos as part of Operation Plumbbob. When the 1-kiloton nuke went off below, the facility effectively became a nuclear potato cannon, giving the cap a gigantic kick. A high-speed camera trained on the lid caught only one frame of it moving upward before it vanished—which means it was moving at a minimum of 66 km/s. The cap was never found.

It would blast the material out of the way with powerful shockwaves, leaving a trail of superhot plasma behind it. This would be something never before seen in the history of the universe: an underground shooting star.

If 10 percent of them are close to your age, that would be around 50,000 people in a lifetime. Given that you have 500,000,000 potential soul mates, it means you would find true love only in one lifetime out of 10,000.

The whole process of claiming a colony (on land already occupied by other people) is awfully arbitrary in the first place. Essentially, the British built their empire by sailing around and sticking flags on random beaches.

We keep trying to make our units of measurement make sense. But the truth is that the world is an absurd place; why not embrace it? It’s true, unit conversion errors have caused us to lose space probes once in a while. But isn’t that a small price to pay for silliness?

At supersonic and hypersonic speeds, a shockwave forms around the steak that helps protect it from the faster and faster winds. The exact characteristics of this shock front—and thus the mechanical stress on the steak—depend on how an uncooked 8-ounce filet tumbles at hypersonic speeds. I searched the literature, but was unable to find any research on this.

In Thor the main character is at one point spinning his hammer so fast that he creates a strong tornado. Would this be possible in real life?

If a Venus fly trap could eat a person, about how long would it take for the human to be fully de-juiced and absorbed?

So, what year did a single typical desktop computer surpass the combined processing power of humanity? 1994.

If an asteroid was very small but supermassive, could you really live on it like the Little Prince?

computers are limited by our ability to program them, so we’ve got a built-in advantage. Instead,

Oooh, look at me, I looked up a quote!

Rule of thumb: One person per square meter is a light crowd, four people per square meter is a mosh pit. 2

2 Note: If you’re ever trapped with me in a burning building, and I suggest an idea for how we could escape the situation, it’s probably best to ignore me.

Then the 92nd little pig built a house out of depleted uranium and the wolf was like, "dude.

The Moon would shine as brightly as the midmorning sun, and by the end of the two minutes, the lunar regolith would be heated to a glow.

Q. How hard would a puck have to be shot to be able to knock the goalie himself backward into the net?

You might notice that we’re ignoring the pockets of space between the moles. In a moment, you’ll see why.

Major League Baseball Rule 6.08(b) suggests that in this situation, the batter would be considered “hit by pitch,” and would be eligible to advance to first base.

I would say time is definitely one of my top three favorite dimensions.

Of the 28 people killed by lightning in the US in 2012, 13 were standing under or near trees.

you could stack a quarter of a million 2x2 bricks on top of each other before the bottom one collapsed.9

for a typical inkjet printer, the real-life cost of ink ran from 5 cents per page for black-and-white to around 30 cents per page for photos.

force of gravity at the scale factory isn’t necessarily the same as the force of gravity at your house.

People often wonder whether we could harvest electrical power from lightning.

Hans Moravec’s book Robot: Mere Machine to Transcendent Mind.

REENTERING SPACECRAFT HEAT UP because they’re compressing the air in front of them (not, as is commonly believed, because of air friction).

That’s one in 27 quinquatrigintillion.

If you want to transfer a few hundred gigabytes of data, it’s generally faster to FedEx a hard drive than to send the files over the Internet.

Why don’t we try to destroy tropical cyclones by nuking them?” by Chris Landsea.

engineer sees a glass that’s twice as big as it needs to be, the surrealist sees a giraffe eating a necktie, etc.

Temperature is a measure of the average kinetic energy of a collection of particles.

How fast would a human have to run in order to be cut in half at the bellybutton by a cheese-cutting wire? —Jon Merrill

much eye contact as possible. We could put together massive conveyer belts

Maybe we’ll all be killed by nanobots hours after you read this sentence.

Our most lasting relic will probably be the layer of plastic we’ve deposited across the planet.

Given humanity’s current knowledge and capabilities, is it possible to build a new star?

Statistically, your first neutrino interaction probably happens somewhere around age ten.

Okay, you can stop looking at your hand now.

To this day I have no idea where I got “3 billion” and “5 billion” from. Clearly, I didn’t really get how numbers worked.

If the optimist says the glass is half full, and the pessimist says the glass is half empty, the physicist ducks.

It’s not that the wind is blowing, it’s what the wind is blowing.

How many houses are burned down in the United States every year? What would be the easiest way to increase that number by a significant amount (say, at least 15%)?

What would happen if you made a periodic table out of cube-shaped bricks, where each brick was made of the corresponding element?

Suppose you’re meeting a friend in an American town that neither of you have been to before. You don’t have a chance to plan a meeting place beforehand. Where do you go?

What if everyone who took the SAT guessed on every multiple-choice question? How many perfect scores would there be?

At the top of the Luxor Hotel in Las Vegas is the most powerful spotlight on Earth.

Just watch out for salmonella. And the Andromeda Strain.

On one hand, humans and computers do very different types of thinking, so comparing them is like comparing apples and oranges. On the other hand, apples are better.

If you’re in Sacramento, Seattle, Canberra, Kolkata, Hyderabad, Phnom Penh, Cairo, Beijing, central Japan, central Sri Lanka, or Portland, space is closer than the sea.

But maybe it won’t. Maybe it will take on a role like the TCP protocol, where it becomes a piece of infrastructure on which other things are built, and has the inertia of consensus.

the most common genetic disorder caused by inbreeding is spinal muscular atrophy (SMA). SMA causes the death of the cells in the spinal cord, and is often fatal or severely disabling.

A submarine is about as safe as a submarine safe (a submarine safe is not to be confused with a safe in a submarine - a safe in a submarine is substantially safer than a submarine safe).

So Yoda sounds like our best bet as an energy source. But with world electricity consumption pushing 2 terawatts, it would take a hundred million Yodas to meet our demands. All things considered, switching to Yoda power probably isn’t worth the trouble—though it would definitely be green.

The ISS moves so quickly that if you fired a rifle bullet from one end of a football field,7 the International Space Station could cross the length of the field before the bullet traveled 10 yards.8

Gravity in low Earth orbit is almost as strong as gravity on the surface. The Space Station hasn’t escaped Earth’s gravity at all; it’s experiencing about 90 percent the pull that we feel on the surface.

for raw bandwidth of FedEx, the Internet will probably never beat SneakerNet. However, the virtually infinite bandwidth of a FedEx-based Internet would come at the cost of 80,000,000-millisecond ping times.

If you call a random phone number and say “God bless you,” what are the chances that the person who answers just sneezed? —Mimi A. It’s hard to find good numbers on this, but it’s probably about 1 in 40,000.

How much computing power could we could achieve if the entire world population stopped whatever we are doing right now and started doing calculations? How would it compare to a modern-day computer or smartphone?

Air has very little viscosity. That is, it’s not gooey. That means things flying through the air experience drag because of the momentum of the air they’re shoving out of the way—not from cohesion between the air molecules. It’s more like pushing your hand through a bathtub full of water than a bathtub full of honey.

This means the last few years of hard-drive production—which, thanks to increasing size, represents the majority of global storage capacity—would just about fill an oil tanker. So, by that measure, the Internet is smaller than an oil tanker.

Could you boil tea if you just stirred it hard enough? No. The first problem is power. The amount of power in question, 700 watts, is about a horsepower, so if you want to boil tea in two minutes, you’ll need at least one horse to stir it hard enough.

Telescopes and bathyscapes and sonar probes of Scottish lakes, Tacoma Narrows bridge collapse explained with abstract phase-space maps, some x-ray slides, a music score, Minard's Napoleonic war: the most exciting new frontier is charting what's already here.

You can work through the physics of interstellar radio attenuation,1 but the problem is captured pretty well by considering the economics of the situation: If your TV signals are getting to another star, you’re wasting money. Powering a transmitter is expensive, and creatures on other stars aren’t buying the products in the TV commercials that pay your power bill. The full picture is more complicated, but the bottom

Our most lasting relic will probably be the layer of plastic we’ve deposited across the planet. By digging up oil, processing it into durable and long-lasting polymers, and spreading it across the Earth’s surface, we’ve left a fingerprint that could outlast everything else we do.

Heat flow analysis provides a simple rule of thumb: If an unused charger isn’t warm to the touch, it’s using less than a penny of electricity a day. For a small smartphone charger, if it’s not warm to the touch, it’s using less than a penny a year. This is true of almost any powered device.1

But I’ve never seen the Icarus story as a lesson about the limitations of humans. I see it as a lesson about the limitations of wax as an adhesive. The cold of Titan is just an engineering problem. With the right refitting, and the right heat sources, a Cessna 172 could fly on Titan—and so could we.

Q. What if I took a swim in a typical spent nuclear fuel pool? Would I need to dive to actually experience a fatal amount of radiation? How long could I stay safely at the surface? —Jonathan Bastien-Filiatrault A. Assuming you’re a reasonably good swimmer, you could probably survive treading water anywhere from 10 to 40 hours. At that point, you would black out from fatigue and drown. This is also true for a pool without nuclear fuel in the bottom.

If you eat a destroying angel, for the rest of the day you’ll feel fine. Later that night, or the next morning, you’ll start exhibiting cholera-like symptoms—vomiting, abdominal pain, and severe diarrhea. Then you start to feel better. At the point where you start to feel better, the damage is probably irreversible. Amanita mushrooms contain amatoxin, which binds to an enzyme that is used to read information from DNA. It hobbles the enzyme, effectively interrupting the process by which cells follow DNA’s instructions. Amatoxin causes irreversible damage to whatever cells it collects in. Since most of your body is made of cells,4 this is bad. Death is generally caused by liver or kidney failure, since those are the first sensitive organs in which the toxin accumulates. Sometimes intensive care and a liver transplant can be enough to save a patient, but a sizable percentage of those who eat Amanita mushrooms die.

Could you open bottles using nuclear bombs? This is a completely ridiculous suggestion, so it should come as no surprise that it was studied by the US government during the Cold War. Early in 1955, the Federal Civil Defense Administration bought beer, soda, and carbonated water from local stores, then tested nuclear weapons on them.*

Eventually, humans will die out. Nobody knows when,​[​12​]​ but nothing lives forever. Maybe we’ll spread to the stars and last for billions or trillions of years. Maybe civilization will collapse, we’ll all succumb to disease and famine, and the last of us will be eaten by cats. Maybe we’ll all be killed by nanobots hours after you read this sentence. There’s no way to know.

Speed Bump Q. How fast can you hit a speed bump while driving and live? —Myrlin Barber A. Surprisingly fast. First, a disclaimer. After reading this answer, don’t try to drive over speed bumps at high speeds. Here are some reasons: You could hit and kill someone. It can destroy your tires, suspension, and potentially your entire car. Have you read any of the other answers in this book?

A paper by Gordon Moore (of Moore’s law fame) gives figures for the total number of transistors manufactured per year since the 1950s. It looks something like this: Using our ratio, we can convert the number of transistors to a total amount of computing power. This tells us that a typical modern laptop, which has a benchmark score in the tens of thousands of MIPS, has more computing power than existed in the entire world in 1965.

It turns out that if you accelerate at 1 G for several years, you can reach almost any destination in the universe. After a few years have passed [traveling at that rate], the effects of relativity really start to add up. When 3 years have passed for you ... you'll have traveled nearly 10 light-years - far enough to reach many nearby stars. If you continue accelerating, it would take you less than 20 years of your time to reach a neighboring galaxy. If you keep pressing the accelerator for a little over two decades, you'll find your vehicle traveling billions of light-years per subjective "year", carrying you across a substantial fraction of the observable universe.

It might seem confusing that someone navigating toward Earth’s north pole would be attracted to the MRI’s south pole, but that’s because the Earth’s pole names are backward. The “north” end of a magnet is the one that points toward the Earth’s north pole, which means the Earth’s north magnetic pole is technically a south magnetic pole, and vice versa. This is deeply annoying to me, but there’s nothing we can do about it, so we might as well move on.

Blue-green algae, or cyanobacteria, were the first photosynthesizers. They breathed in carbon dioxide and breathed out oxygen. Oxygen is a volatile gas; it causes iron to rust (oxidation) and wood to burn (vigorous oxidation). When cyanobacteria first appeared, the oxygen they breathed out was toxic to nearly all other forms of life. The resulting extinction is called the oxygen catastrophe. After the cyanobacteria pumped Earth’s atmosphere and water full of toxic oxygen, creatures evolved that took advantage of the gas’s volatile nature to enable new biological processes. We are the descendants of those first oxygen-breathers. Many details of this history remain uncertain; the world of a billion years ago is difficult to reconstruct.

Q. What would happen if you tried to hit a baseball pitched at 90 percent the speed of light? —Ellen McManis Let’s set aside the question of how we got the baseball moving that fast. We’ll suppose it’s a normal pitch, except in the instant the pitcher releases the ball, it magically accelerates to 0.9c. From that point onward, everything proceeds according to normal physics. A. The answer turns out to be “a lot of things,” and they all happen very quickly, and it doesn’t end well for the batter (or the pitcher). I

X-Plane tells us that flight on Mars is difficult, but not impossible. NASA knows this, and has considered surveying Mars by airplane. The tricky thing is that with so little atmosphere, to get any lift, you have to go fast. You need to approach Mach 1 just to get off the ground, and once you get moving, you have so much inertia that it’s hard to change course—if you turn, your plane rotates, but keeps moving in the original direction. The X-Plane author compared piloting Martian aircraft to flying a supersonic ocean liner.

Some species moved north faster than others; when Europeans arrived in New England, earthworms had not yet returned. As the ice sheets withdrew, large chunks of ice broke off and were left behind. When these chunks melted, they left behind water-filled depressions in the ground called kettlehole ponds. Oakland Lake, near the north end of Springfield Boulevard in Queens, is one of these kettlehole ponds. The ice sheets also dropped boulders they’d picked up on their journey; some of these rocks, called glacial erratics, can be found in Central Park today.

To test this theory, I sent this picture to my mother and asked her what she thought had happened. She immediately replied,2 “The kid knocked over the vase and the cat is investigating.” She cleverly rejected alternate hypotheses, including: The cat knocked over the vase. The cat jumped out of the vase at the kid. The kid was being chased by the cat and tried to climb up the dresser with a rope to escape. There’s a wild cat in the house, and someone threw a vase at it. The cat was mummified in the vase, but arose when the kid touched it with a magic rope. The rope holding the vase broke and the cat is trying to put it back together. The vase exploded, attracting a child and a cat. The child put on the hat for protection from future explosions. The kid and cat are running around trying to catch a snake. The kid finally caught it and tied a knot in it.

How much physical space does the Internet take up? —Max L A. THERE ARE A LOT of ways to estimate the amount of information stored on the Internet, but we can put an interesting upper bound on the number just by looking at how much storage space we (as a species) have purchased. The storage industry produces in the neighborhood of 650 million hard drives per year. If most of them are 3.5-inch drives, that’s 8 liters (2 gallons) of hard drive per second. This means the last few years of hard-drive production—which, thanks to increasing size, represents the majority of global storage capacity—would just about fill an oil tanker. So, by that measure, the Internet is smaller than an oil tanker. Q.

The official record for the fastest manmade object is the Helios 2 probe, which reached about 70 km/s in a close swing around the Sun. But it’s possible the actual holder of that title is a two-ton metal manhole cover. The cover sat atop a shaft at an underground nuclear test site operated by Los Alamos as part of Operation Plumbbob. When the 1-kiloton nuke went off below, the facility effectively became a nuclear potato cannon, giving the cap a gigantic kick. A high-speed camera trained on the lid caught only one frame of it moving upward before it vanished—which means it was moving at a minimum of 66 km/s. The cap was never found. Now, 66 km/s is about six times escape velocity, but contrary to common speculation, it’s unlikely the cap ever reached space. Newton’s impact depth approximation suggests that it was either destroyed completely by impact with the air or slowed and fell back to Earth. When we turn it back on, our reactivated hair dryer box, bobbing in lake water, undergoes a similar process. The heated steam below it expands outward, and as the box rises into the air, the entire surface of the lake turns to steam. The steam, heated to a plasma by the flood of radiation, accelerates the box faster and faster. Photo courtesy of Commander Hadfield Rather than slam into the atmosphere like the manhole cover, the box flies through a bubble of expanding plasma that offers little resistance. It exits the atmosphere and continues away, slowly fading from second sun to dim star. Much of the Northwest Territories is burning, but the Earth has survived.

A. There are people who collect elements. These collectors try to gather physical samples of as many of the elements as possible into periodic-table-shaped display cases.1 Of the 118 elements, 30 of them—like helium, carbon, aluminum, and iron—can be bought in pure form in local retail stores. Another few dozen can be scavenged by taking things apart (you can find tiny americium samples in smoke detectors). Others can be ordered over the Internet. All in all, it’s possible to get samples of about 80 of the elements—90, if you’re willing to take some risks with your health, safety, and arrest record. The rest are too radioactive or short-lived to collect more than a few atoms of them at once. But what if you did? The periodic table of the elements has seven rows.2 You could stack the top two rows without much trouble. The third row would burn you with fire. The fourth row would kill you with toxic smoke. The fifth row would do all that stuff PLUS give you a mild dose of radiation. The sixth row would explode violently, destroying the building in a cloud of radioactive, poisonous fire and dust. Do not build the seventh row.

Eventually, humans will die out. Nobody knows when,12 but nothing lives forever. Maybe we’ll spread to the stars and last for billions or trillions of years. Maybe civilization will collapse, we’ll all succumb to disease and famine, and the last of us will be eaten by cats. Maybe we’ll all be killed by nanobots hours after you read this sentence. There’s no way to know. A million years is a long time. It’s several times longer than Homo sapiens has existed, and a hundred times longer than we’ve had written language. It seems reasonable to assume that however the human story plays out, in a million years it will have exited its current stage. Without us, Earth’s geology will grind on. Winds and rain and blowing sand will dissolve and bury the artifacts of our civilization. Human-caused climate change will probably delay the start of the next glaciation, but we haven’t ended the cycle of ice ages. Eventually, the glaciers will advance again. A million years from now, few human artifacts will remain. Our most lasting relic will probably be the layer of plastic we’ve deposited across the planet. By digging up oil, processing it into durable and long-lasting polymers, and spreading it across the Earth’s surface, we’ve left a fingerprint that could outlast everything else we do.