Centimeter Wavelengths https://xkcd.com/3224/ Yes, the cosmic microwave background is great, but what about the earthly microwave foreground? Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3224

Inflation Timeline https://xkcd.com/3223/ Depending what corners of the internet you hang out on, 'regular' may at times awkwardly coexist with 'sexy.' Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3223

Star Formation https://xkcd.com/3222/ It's ok, I still have some nice, cool gas clouds that aren't collapsing. As long as nothing ionizes them, I can continue to enjoy their ... HEY! NO!!! Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3222

Landscape Features https://xkcd.com/3221/ 'Well, there's speculation that it's due to a mantle hotspot.' --a geologist who's trying to cover up the fact that they didn't hear your question Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3221

Rotational Gravity https://xkcd.com/3220/ I don't get it. The peak acceleration for passengers was WAY lower than in the giant-waterslide-loop-the-loop incident the other cruise line fired me for. Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3220

Planets and Bright Stars https://xkcd.com/3219/ (alt-text too long for a BlueSky message, see image alt-text instead) Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3219

Subduction Retrieval https://xkcd.com/3218/ Aww, the oceanic crust and the continental crust are getting married! Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3218

Home Remedies https://xkcd.com/3217/ As always, you are permitted to call one person for guidance, but that person must be a grandparent. Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3217

Bazookasaurus https://xkcd.com/3216/ In contrast to the deep booming sound associated with the cannon in pop culture depictions, recent studies show it actually made more of a 'toot toot!' noise. Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3216

Solar Warning https://xkcd.com/3215/ This replaces the previous solar activity watch, which was issued last month when the sun took off its sunglasses. Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3215

Electric Vehicles https://xkcd.com/3214/ Now that I've finally gotten an electric vehicle, I'm never going back to an acoustic one. Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3214

Dental Formulas https://xkcd.com/3213/ I mean, half of these are undefined. And your multiplication dots are too low; they look like decimal points. Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3213

Little Red Dots https://xkcd.com/3212/ After a lot of analysis, I've determined that they're actually big red dots; they're just very far away. Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3212

Amperage https://xkcd.com/3211/ Oh, and do you have any tips on how to vacuum up copper that's melted into your carpet? Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3211

Eliminating the Impossible https://xkcd.com/3210/ 'If you've eliminated a few possibilities and you can't think of any others, your weird theory is proven right' isn't quite as rhetorically compelling. Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3210

Plums https://xkcd.com/3209/ My icebox plum trap easily captured William Carlos Williams. It took much less work than the infinite looping network of diverging paths I had to build in that yellow wood to ensnare Robert Frost. Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3209

SNEWS https://xkcd.com/3208/ People say setting of fireworks indoors is dangerous, but I looked at their energy release and it's like 10^-40 foe; totally negligible. Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3208

Bad Map Projection: Zero Declination https://xkcd.com/3207/ (alt-text too long for a BlueSky message, see image alt-text instead) Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3207

Installation https://xkcd.com/3206/ Do YOU remember the skylight being this big? Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3206

Carbon Dating https://xkcd.com/3205/ This dating is corroborated by the presence of stone tools at the site, rather than earlier and less effective helium ones. Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3205

Dinosaurs And Non-Dinosaurs https://xkcd.com/3204/ Staplers are actually in Pseudosuchia, making them more closely related to crocodiles than to dinosaurs. Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3204

Binary Star https://xkcd.com/3203/ The discovery of a fully typographical star system comes with a big asterisk. Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3203

Groundhog Day Meaning https://xkcd.com/3202/ Originally, the ceremony used a variety of rodents and mustelids, but over time most people agreed it made sense to standardize on a specific individual ground squirrel in Pennsylvania. Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3202

Proof Without Content https://xkcd.com/3201/ There's also a proof without content of a conjecture without content, but it's left as an exercise for the reader. Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3201

Chemical Formula https://xkcd.com/3200/ Some of the atoms in the molecule are very weakly bound. Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3200

Early Arthropods https://xkcd.com/3199/ (alt-text too long for a BlueSky message, see image alt-text instead) Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3199

Double-Pronged Extension Cord https://xkcd.com/3198/ 'Oh, and can I borrow 50 sacks of loose flour, a pile of lithium-ion batteries, a bucket of bleach, and a bucket of vinega--' 'NO!!!!!!' Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3198

Cost Savings https://xkcd.com/3197/ Unfortunately, my scheme to trick NASA has now taken over a decade longer than planned and has run way over budget. Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3197

Aurora Coolness https://xkcd.com/3196/ I've had countless nights where the line never left the bottom zone of the graph, but the few moments where it's climbed all the way to the top have made up for them all. Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3196

International Station https://xkcd.com/3195/ Welcome to the International Space Station Exclamation Point! Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3195

16 Part Epoxy https://xkcd.com/3194/ (alt-text too long for a BlueSky message, see image alt-text instead) Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3194

Sailing Rigs https://xkcd.com/3193/ I wanted to make the world's fastest yawl, so I made the aft sail bigger, but apparently that means it's not a yawl anymore! It's a real ketch-22. Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3193

Planetary Alignment https://xkcd.com/3192/ We're going to need to modify the surface to mount it on the test stand. Which ocean basin do you like the least? Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3192

Superstition https://xkcd.com/3191/ (alt-text too long for a BlueSky message, see image alt-text instead) Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3191

Tensegrity https://xkcd.com/3190/ (alt-text too long for a BlueSky message, see image alt-text instead) Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3190

Conic Sections https://xkcd.com/3189/ They're not generally used for crewed spacecraft because astronauts HATE going around the corners. Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3189

Anyone Else Here https://xkcd.com/3188/ Anyone else watching this Youtube video in 1954? If so, my last trip definitely messed with the timeline. Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3188

High Altitude Cooking Instructions https://xkcd.com/3187/ 1,300,000-1,400,000 ft: Ask a crew member to show you how to use the ISS food warmer. Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3187

Truly Universal Outlet https://xkcd.com/3186/ Building Inspectors HATE This One Weird Trick Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3186

Sauropods https://xkcd.com/3185/ Vertebrae Georg Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3185

Funny Numbers https://xkcd.com/3184/ In 1899, people were walking around shouting '23' at each other and laughing, and confused reporters were writing articles trying to figure out what it meant. Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3184

Pole Vault Pole https://xkcd.com/3183/ My goal in life is to be personally responsible for at least one sports rule change. Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3183

Telescope Types https://xkcd.com/3182/ I'm trying to buy a gravitational lens for my camera, but I can't tell if the manufacturers are listing comoving focal length or proper focal length. Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3182

Jumping Frog Radius https://xkcd.com/3181/ (alt-text too long for a BlueSky message, see image alt-text instead) Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3181

Apples https://xkcd.com/3180/ The experimental math department's budget is under scrutiny for how much they've been spending on trains leaving Chicago at 9:00pm traveling at 45 mph. Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3180

Fishing https://xkcd.com/3179/ 'That's definitely above the catch-and-release size minimum for planetesimals.' 'I'm going to throw it back anyway.' Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3179

Hyperacute Interdynamics https://xkcd.com/3178/ Our models fall apart where the three theories overlap; we're unable to predict what happens when a nanometer-sized squirrel eats a grapefruit with the mass of the sun. Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3178

Chessboard Alignment https://xkcd.com/3177/ Luckily, the range is limited by the fact that the square boundary lines follow great circles. Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3177

Inverted Catenaries https://xkcd.com/3176/ Some tires are marketed as 'all-shape tires,' but if driven in a climate with both inverted catenary falls and triangle falls, they wear out really fast. Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3176

Website Task Flowchart https://xkcd.com/3175/ Tired of waiting on hold? Use our website to chat with one of our live agents, who are available to produce words at you 24/7! Explain xkcd: https://www.explainxkcd.com/wiki/index.php/3175