Hi, I’m Manu, a biking web developer. I’ve been writing on here since June 2002 about a bunch of different topics. My favorite posts are tagged with ✪.

Why “plothole.net”? As defined on wikipedia,

a plot hole, plothole or plot error is a gap or inconsistency in a storyline that goes against the flow of logic established by the story’s plot. Such inconsistencies include such things as illogical or impossible events, and statements or events that contradict earlier events in the storyline.

This definition suits my life pretty well.

Thanks for reading!

How to

I’m a huge fan of Randall Munroe. 3 years ago I wrote about Thing Explainer, now it’s the turn of the spiritual successor of What if:

How to: absurd scientific advice for common real-world problems
How to: absurd scientific advice for common real-world problems

I think reading through the table of contents gives you the best idea of how nuts the book is:

How to Jump Really High
How to Throw a Pool Party
How to Dig a Hole
How to Play the Piano
How to Listen to Music
How to Make an Emergency Landing
How to Cross a River
How to Move
How to Keep Your House from Moving
How to Chase a Tornado
How to Build a Lava Moat
How to Throw Things
How to Play Football
How to Predict the Weather
How to Go Places
How to Play Tag
How to Ski
How to Mail a Package
How to Power Your House (on Earth)
How to Power Your House (on Mars)
How to Make Friends
How to Blow out Birthday Candles
How to Walk a Dog
How to Send a File
How to Charge Your Phone
How to Take a Selfie
How to Catch a Drone
How to Tell If You’re a Nineties Kid
How to Win an Election
How to Decorate a Tree
How to Build a Highway
How to Get Somewhere Fast
How to Be On Time
How to Dispose of This Book

I found that the topics at the beginning are crazier and kinda useless fun, whereas towards the end you actually learn some things, about photography, weather forecast, relativity, etc.

Here’s an example of a fabulous tangent Randall gets on in How to Throw a Pool Party when he wonders how you could fill your pool with water:

In many areas, online retailers like Amazon offer same-day delivery. A 24-pack of Fiji water bottles currently costs about $25. If you have $150,000 to spare—plus another $100,000 or so for same-day delivery—you can simply order a pool in bottle form. As a bonus, your new pool will consist entirely of water shipped from Fiji.

This will present a new challenge. When the water is delivered, you’ll need to get it all into the pool.

This will be trickier than you might have thought. Sure, you could unscrew the cap on each bottle and dump the water into the pool one by one, but this would take a few seconds per bottle. Since there are 150,000 bottles and only 86,400 seconds in a day, anything that takes more than a second per bottle is definitely not going to work.

For the How to Make an Emergency Landing chapter, Randall contacted none other than astronaut Chris Hadfield who played along really nicely:

What do I do if I somehow accidentally close my sleeve in the cockpit door, and can’t reach the front of the cockpit? But I can reach some objects—maybe trays of in-flight meals—that I can throw at the controls. If I’m good at throwing, could I land by hitting the right controls?

If it’s a single-engine plane, no way. But in a plane with multiple engines, it might technically be possible. The way you’re going to control things is power. If you have engines on each side, by moving the throttles up and down you can climb, and you can turn that way, too. If you’re really careful about throwing the utensils, you can fly an airplane just by moving the throttles up and down.

There was a DC-10 that lost all hydraulics, over Sioux City, and the pilots managed to get control and steer that airplane all the way around to the runway using only the throttles.

In How to Move, the author obviously suggests to move your house, not the stuff inside your house, using helicopters:

A multi-helicopter lift would present a few challenges. The helicopters would have to pull in different directions to avoid colliding, which would reduce their overall capacity. They would also need to coordinate carefully to avoid collisions. But you could solve both these problems by attaching the helicopters together rigidly, so they lifted as a single aircraft.

This idea sounds ridiculous, so, unsurprisingly, the US military studied it during the Cold War. In a 178-page report, they analyzed the idea of producing a super heavy-lift helicopter by the sophisticated engineering technique of taking two helicopters and gluing them together. The project never went past the planning stages, possibly because the engineering diagrams looked a lot like mating dragonflies.

US military ridiculousness
US military ridiculousness

I think I heard about the ski lift of some resort around Zermatt slowly moving from Italy into Switzerland (or maybe I misremember). This snippet taken from How to Keep Your House from Moving is very similar:

The International Boundary Commission, the body in charge of managing the US-Canada border, periodically publishes updated coordinates for the border, but their publications don’t change where the border is—they just provide everyone with better information about it. The actual border is defined by “boundary monuments”—usually granite obelisks and steel pipes driven into the ground—along with photos and surveying information. If the land moves, the borders move with it, and the coordinates need to be updated.

To reduce the need for these updates, different countries and organizations often use slightly different latitude and longitude grids—geodetic datums—which are anchored to a particular tectonic plate. These grids move with the plate, and may differ from one another by several meters or more. Thanks to these different grids, no latitude/longitude coordinates are ever really precise and unambiguous without lots of information about the datum they’re in. If you think that sounds like a huge headache for anyone who has to deal with precise coordinates, you’re right.

There is a saying in German for the red sky phenomenon, but I could never remember which way around it was. Does a red sky in the evening mean good or bad weather? Thanks to this book, I know why it happens, and will hopefully remember now:

The “red sky” trick gets around this by using the Sun. Red wavelengths pass through air more easily than blue ones. When the Sun is setting in the west, its light passes through hundreds of miles of atmosphere—becoming extremely red in the process—before hitting the clouds above you. Shorter blue wavelengths bounce off the air and go off in other directions. This is why the sky is blue—it reflects blue light. White clouds reflect all colors, so when red light shines on them, they look red, too.

red sky at night
red sky at night

If there are storm clouds to your west, the red sunlight is stopped before it can get to you, and the sunset doesn’t look particularly red:

normal sky at night
normal sky at night

On the other hand, if there’s clear air for hundreds of miles to your east, the sunlight passes all the way through to reach the sky above you, turning it red. If there are any clouds overhead, the red light illuminates them, creating a spectacular sunrise.

Having a whole chapter co-written with Chris Hadfield wasn’t enough. Randall had Serena Williams test a theory for him for How to Catch a Drone:

I was curious to test this in the real world, and one sport I couldn’t find good data on was tennis. I found some studies of tennis pro accuracy, but they involved hitting targets marked on the court, rather than in the air.

So I reached out to Serena Williams.

To my pleasant surprise, she was happy to help out. Her husband, Alexis, offered a sacrificial drone, a DJI Mavic Pro 2 with a broken camera. They headed out to her practice court to see how effective the world’s best tennis player would be at fending off a robot invasion.

Nukes suck:

But even as the radioactive elements settle out of the environment and slowly decay into more inert forms, their imprint is left on us. No one really knows how many people have died from cancer caused by nuclear testing. The low estimates are in the thousands. The high estimates are in the hundreds of thousands. The quiet, hidden death toll from these weapons tests may well be greater than the death toll from the bombings of Hiroshima and Nagasaki. The legacy of the choices we made in that short period after World War II will be with us for a long time.

A science book is not complete without some time zone mindfucks. Here’s a fun bit from How to Be on Time:

In 2010, religious radio host Harold Camping predicted that the end of the world would begin with the Rapture on May 21, 2011, at 6:00 p.m. local time. Since the apocalypse happened according to local time, this meant that the end of the world was supposed to begin at the Republic of Kiribati in the Pacific Ocean, just west of the International Date Line, and sweep westward around the planet, time zone by time zone.

If some country wants to check whether the world ends at some future date, they can simply pass a law advancing their clock to, say, 12:00 p.m. on January 1, 3019, and then take a look around. If nothing happens, they can move the clocks back, and we’ll all know that the next thousand years are safe—at least from apocalypses that happen in local time.