xkcd Bot

Siege Engine https://xkcd.com/3316/ They initially thought the containment structure alone would be sufficient, but for good measure they decided to include the Elephant's Foot inside. Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3316

Forms of Water https://xkcd.com/3315/ The 'light' refers to bremsstrahlung. Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3315

Vulnerability https://xkcd.com/3314/ Other numbers are largely unaffected, but anyone using '4' for their certificate key is urged to upgrade to '5'. Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3314

Fusion Device https://xkcd.com/3313/ I don't see why people have trouble doing this at room temperature. Using hot rivets would honestly have been MORE work. Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3313

Momentum Demonstration https://xkcd.com/3312/ "I'm doing really well on the Hertzsprung-Russell academic diagram, which has spectral class on one axis and Rate My Professors rating on the other." Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3312

Planet Database https://xkcd.com/3311/ Atmospheric transmission spectroscopy has revealed that the sunsets from the observatory are really pretty. Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3311

Rejected Space Mission Profiles https://xkcd.com/3310/ (alt-text too long for a BlueSky message, see image alt-text instead) Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3310

Dogcatcher https://xkcd.com/3309/ People out here catching strays out here catching strays Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3309

Juice https://xkcd.com/3308/ I need to push some updates to the remote sensing instruments, which are there to measure the surface and definitely not do anything else. Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3308

Spectrum Allocation https://xkcd.com/3307/ Rumor has it that they're finally auctioning off the zeppelin navigation bands, but everyone is worried that the scary boat captains will express interest. Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3307

Accelerator Energies https://xkcd.com/3306/ Fans at Daytona always get extra excited when officials decide to introduce some antimatter cars circling the track in the opposite direction. Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3306

Ground Effect https://xkcd.com/3305/ Runners looking for aerodynamic advantage typically wear sneakers because some fancy dress shoes can create wingtip vortices. Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3305

Jupiter Icy Moons Explorer https://xkcd.com/3304/ "I did briefly visit Venus in August 2025, but I figured out the mistake on my own because it didn't have any moons." Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3304

Slab Graveyard https://xkcd.com/3303/ It's ok if you want to close close your eyes for the slab graveyard, so you can still have fun riding the mantle plume back up afterward! Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3303

Voyager Instruments https://xkcd.com/3302/ Convincing him to turn off the stupid laser show and useless sound system was such a huge ordeal that no one has wanted to do it again. Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3302

Stargazing 5 https://xkcd.com/3301/ (alt-text too long for a BlueSky message, see image alt-text instead) Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3301

Tyrannosaurus https://xkcd.com/3300/ Many of the smaller dinosaurs seem to have largely preyed on housecats. Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3300

Summer https://xkcd.com/3299/ You should probably get back to shore before spring hits. Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3299

Aerospace Flowchart https://xkcd.com/3298/ Someday, we will find the problem that goes with this solution. Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3298

OH Scale https://xkcd.com/3297/ To access distant parts of the project, I ended up building a regular-scale passenger train inside each rail. Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3297

Fault Taunting https://xkcd.com/3296/ One of the first things they teach you is to NEVER play with the geology toy over a mantle hotspot. Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3296

Semaphore https://xkcd.com/3295/ The speed of light in air is 50% faster than in fiber, but it's a challenge to get the arms to move fast enough to realize the latency advantage. Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3295

Asteroid Mission https://xkcd.com/3294/ Lander, this is Houston. There's been a request that you turn clipping back on and instead set the mass to 1kg. The theorists believe that will be pretty funny. Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3294

Handedness https://xkcd.com/3293/ A 'left-handed specialist' is a physicist who studies the weak interaction. Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3293

Geology Class https://xkcd.com/3292/ The rise of AI review bombing tools threatens to take away a crucial source of experience for geology undergraduates. Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3292

Launchpad https://xkcd.com/3291/ It does come at the cost of some launchpad expansions and increased fuel requirements, but that all comes out of the facility's budget. Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3291

Trade https://xkcd.com/3290/ (alt-text too long for a BlueSky message, see image alt-text instead) Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3290

Highway Signs https://xkcd.com/3289/ Highway engineers like Planck units because, like the speed of light, the energy capacity of a typical car's gas tank is 1. Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3289

Archery Feat https://xkcd.com/3288/ Update: I would not have embarked on this powerscaling venture if I'd known how thoroughly Mark Twain was going to roast me. Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3288

Perseids https://xkcd.com/3287/ Recently I've been watching the Daytime Perseids. I haven't seen a meteor from them yet, but the clouds are pretty and the snacks are good. Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3287

Particle Physics Equipment https://xkcd.com/3286/ The one that sounds like the oracle at the center of the galaxy where the hero travels to hear a prophecy is probably Brookhaven National Laboratory's now-dismantled COSMOTRON. Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3286

Accretionary Arc https://xkcd.com/3285/ The late Triassic rifting was caused by a dinosaur trying to use the control panel to escape a predator, but it was eaten before the continent could fully separate. Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3285

Geology Building https://xkcd.com/3284/ The administration thinks it's weird, but the geologists say it looks normal. Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3284

Size and Lifespan https://xkcd.com/3283/ With their 13 years recording and performing together and two humans worth of mass, the White Stripes are sandwiched neatly between gray wolves and blue whales. Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3283

Trick Play https://xkcd.com/3282/ I've been trying to find out whether the Laws of the Game take the axiom of choice or not, but FIFA officials keep blocking my number. Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3282

Antiques Roadshow https://xkcd.com/3281/ (alt-text too long for a BlueSky message, see image alt-text instead) Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3281

Maze https://xkcd.com/3280/ As a side effect of the research, mice are now the only known animals other than humans to have developed a Backrooms mythology. Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3280

Main Span https://xkcd.com/3279/ Wind stress? Don't be silly. When has wind stress ever been a problem for a suspension bridge? Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3279

Vera Rubin Observatory https://xkcd.com/3278/ 'Spurious signals from the kitchen' is harder for an optical telescope than a radio one, but with enough determination and creativity, I believe it's possible. Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3278

Forth https://xkcd.com/3277/ I NOTATION POLISH REVERSE ❤️ Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3277

Recursive Trucker's Hitch https://xkcd.com/3276/ As if the americium smoke detector incident wasn't enough, now nuclear regulators have ANOTHER reason to worry about the Boy Scouts. Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3276

Calibration Nobel https://xkcd.com/3275/ We would like to once again apologize to Dr. Jones for last year's mistaken announcement. We should really have double-checked the envelope for this award in particular. Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3275

Arthurian Connector https://xkcd.com/3274/ (alt-text too long for a BlueSky message, see image alt-text instead) Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3274

Latitude and Longitude https://xkcd.com/3273/ NGS and IERS are complaining that they left CLEAR instructions to set the washing machine to WGS84 (G2296) instead of WGS84 (G730). Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3273

Time Change https://xkcd.com/3272/ (alt-text too long for a BlueSky message, see image alt-text instead) Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3272

The Princess and the Pea https://xkcd.com/3271/ Once we've fully explored this space, we can start varying the number of princesses. Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3271

Toasting Marshmallows https://xkcd.com/3270/ (alt-text too long for a BlueSky message, see image alt-text instead) Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3270

Airport Meeting https://xkcd.com/3269/ (alt-text too long for a BlueSky message, see image alt-text instead) Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3269

Offside https://xkcd.com/3268/ The arbiter gave my knight a red card for capturing with cleats up :( Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3268

Types of Tornado Alert https://xkcd.com/3267/ I hate the unearthly sound my phone makes when the weather service issues a tornado harbinger. Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3267