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Back in 2015, Tynan DeBold and Dov Friedman created a series of graphics for the WSJ showing the impact of the introduction of vaccines in the US. Here’s the infographic for measles:
And for polio:
Vaccines are in the running for the greatest human invention ever. You can see the rest of the charts (for hepatitis A, mumps, pertussis, rubella, and smallpox) here.
See also The stunning success of vaccines in America, in one chart.
Oh wow, this is cool: an article in Scientific American about the Arecibo message, the first message purposely sent by humanity out into interstellar space. The piece is written by science writer Nadia Drake — the daughter of Frank Drake, who designed the message — and it digs into the details of how the whole thing came about.
I’ve somehow never read about the Arecibo message before. It was sent out from the Arecibo Telescope in Puerto Rico on November 16, 1974 towards global cluster M13. The message was in binary and when properly decoded upon receipt, should look like this:
The drawing on the right is Frank Drake’s recently discovered first draft of the message.
Dad targeted a globular cluster of stars called Messier 13 (M13), or the Great Cluster in the constellation of Hercules, because it would conveniently be overhead at the time of the ceremony (nestled in a sinkhole, Arecibo’s giant dish was not fully steerable). In about 25,000 years, Dad’s message will reach M13 — or at least part of it, because the majority of the cluster’s thousands of stars will have moved out of the telescope’s beam by then. But anyone who’s around to detect the Arecibo transmission, and who figures out how to decode it, will have a blueprint telling them a lot about us: what we look like, which chemical elements and biomolecules make up our DNA, what our planetary system is and how many of us existed in 1974. Dad’s transmission concluded with a binary encoded representation of the Arecibo dish itself.
Read the whole thing…it’s fascinating.
Btw, in addition to creating the Arecibo message, Frank Drake also designed the Drake equation (“a probabilistic argument used to estimate the number of active, communicative extraterrestrial civilizations in the Milky Way Galaxy”), helped design the Pioneer plaque and the Voyager Golden Record, and generally kickstarted the whole SETI effort. (via @https://bsky.app/profile/astrokatie.com)
So we all know the color purple has always been associated with royalty because the dye used to make it was extremely limited because you could only get it from the Phoenician city of Tyre where a tiny snail lived. Dye makers had to “crack open the snail’s shell, extract a purple-producing mucus and expose it to sunlight for a precise amount of time,” and it took 250K snails to make an ounce of dye. But did we know purple isn’t like all the other colors?
Most of you here probably know that our perception of color comes down to physics. Light is a type of radiation that our eyes can perceive, and it spans a certain range of the electromagnetic spectrum. Individual colors are like building blocks in white light: they are subdivisions of the visible spectrum. For us to perceive an object as being of a certain color, it needs to absorb some of the subdivisions in the light that falls on it (or all of them, for black). The parts it reflects (doesn’t absorb) are what gives it its color. But not so for purple, because it is a non-spectral color.
Hahahah. Yessssss. Pound sand, Harold!
I am predisposed to like videos about meteorite craters but this was even more interesting than I anticipated.
A nice example of a crater 2-3 km wide is Rotor Kamm in southern Africa. I should mention that we’re easily into city killer impacts here, in case you’re wondering.
You can explore the Earth Impact Database on their website. (via @michaelhobbes.bsky.social)
A pair of physicists from MIT and Jefferson Lab and an animator have created a new visualization of the atomic nucleaus.
For the first time, the sizes, shapes and structures of nuclei in the quantum realm are visualized using animations and explained in the video.
The video also establishes what appears to be a new unit of measure with an adorable name, the babysecond:
To better define the velocities of particles at such small distance scales, we establish the baby second as 10^-23 seconds. A photon moving at the speed of light crosses three femtometers (a bit more than the radius of oxygen-16) in one baby second.
From the NIH, a collection of 2,000+ public domain science and medical art visuals (molecules, plants, viruses, proteins, brushes for repeating items like DNA, fungi, equipment…). High-resolution, free to use — scientists on social media seem pretty pumped about this.
See also PhyloPic, a collection of 10,000 “free silhouette images of animals, plants, and other life forms, available for reuse under Creative Commons licenses”. (via @waldo.net)
From 1980 to the present, a timeline map of every earthquake in the world with a magnitude of 5 or above. You can play around with different parameters and data, so you can see where the different tectonic plates are, just see where the biggest earthquakes occurred, or add in volcanic eruptions. You can also draw a cross section and it will show how deep the quakes occurred along that line.
Wow, check out this just-released image from the JWST team of star cluster NGC 602.
The local environment of this cluster is a close analogue of what existed in the early Universe, with very low abundances of elements heavier than hydrogen and helium. The existence of dark clouds of dense dust and the fact that the cluster is rich in ionised gas also suggest the presence of ongoing star formation processes. This cluster provides a valuable opportunity to examine star formation scenarios under dramatically different conditions from those in the solar neighbourhood.
It is very worth your time to click through and look at this image in all of its massive celestial glory. I found this image via Phil Plait, who calls it “one of the most jaw-droppingly mind stomping images I’ve seen from JWST” and, directing us back to the science (remember the science?!), notes that NGC 602 is actively forming stars (it’s only about 5 million years old) and that it depicts “the first young brown dwarfs outside our Milky Way”. Cool!
Out today from National Geographic is Infinite Cosmos, a gorgeous-looking book by Ethan Siegel (intro by Brian Greene). It’s about the history of the JWST, humanity’s biggest ever space telescope, a machine that allows us to peer deeper & clearer into the universe than ever before, and some of the amazing results obtained through its use.
Siegel wrote a piece about the book for Big Think, which includes an excerpt. Gravitational lensing is so cool:
Even with its unprecedented capabilities, JWST’s views of the universe are still finite and limited. The faintest, most distant objects in the cosmos — including the very first stars of all — remain invisible even in the longest-exposure JWST images acquired to date. The universe itself offers a natural enhancement, however, that can reveal features that would otherwise remain unobservable: gravitational lensing.
Whenever a large amount of mass gathers together in one location, it bends and distorts the fabric of the surrounding space-time, just as the theory of general relativity dictates. As light from background objects even farther away passes close to or through that region of the universe, it not only gets distorted but also gets magnified and potentially bent, either into multiple images or into a complete or partial ring. The foreground mass behaves as a gravitational lens. The amount of mass and how it’s distributed affect the light passing through it, amplifying the light coming from those background sources.
Infinite Cosmos is available for purchase at Amazon and Bookshop.
Ross Anderson and I share a favorite web page, Wikipedia’s Timeline of the Far Future, which he wrote about for the Atlantic: For How Much Longer Can Life Continue on This Troubled Planet?
Like the best sci-fi world building, the Timeline of the Far Future can give you a key bump of the sublime. It reminds you that even the sturdiest-seeming features of our world are ephemeral, that in 1,100 years, Earth’s axis will point to a new North Star. In 250,000 years, an undersea volcano will pop up in the Pacific, adding an extra island to Hawaii. In the 1 million years that the Great Pyramid will take to erode, the sun will travel only about 1/200th of its orbit around the Milky Way, but in doing so, it will move into a new field of stars. Our current constellations will go all wobbly in the sky and then vanish.
Some aspects of the timeline are more certain than others. We know that most animals will look different 10 million years from now. We know that the continents will slowly drift together to form a new Pangaea. Africa will slam into Eurasia, sealing off the Mediterranean basin and raising a new Himalaya-like range across France, Italy, and Spain. In 400 million years, Saturn will have lost its rings. Earth will have replenished its fossil fuels. Our planet will also likely have sustained at least one mass-extinction-triggering impact, unless its inhabitants have learned to divert asteroids.
I wrote about the timeline back in 2012 (and again in 2017 & 2019).
The timeline of the far future article is far from the longest page on Wikipedia, but it might take you several hours to get through because it contains so many enticing detours. What’s Pangaea Ultima? Oooh, Roche limit! The Degenerate Era, Poincar’e recurrence time, the Big Rip scenario, the cosmic light horizon, the list goes on and on.
In a collaboration with Red Bull & Prada (uh, ok) and with the help of the Polish State Railways, Dawid Godziek rode a mountain bike on a ramps course on top of a moving train, performing tricks & flips between cars. The train and rider moved at the same speed in opposite directions, which made it seem as though, from the perspective of someone on the ground next to the train, that the rider is nearly horizontally stationary.
The result is trippy & counterintuitive and also a demonstration of Newton’s laws of motion & frames of reference. But since Godziek was not riding in a vacuum, there were some real world details to contend with:
We observed something interesting — the lack of air resistance. In theory, this could have made it easier, but the opposite was true. The air resistance creates a tunnel that somehow keeps me in a straight line and doesn’t allow me to shift right or left. Luckily on the recordings we had, the headwind gave me artificial air resistance, which helped me to get a feel for the flight on classic hops. On the tests, the wind was blowing weaker or in a different direction, making shooting tricks difficult. Not bad, right? We’re always complaining about air resistance, and when it wasn’t there, we found that it was impossible to fly without it.
See also Mythbusters shooting a soccer ball out of the back of a moving truck.
The folks at Kurzgesagt have done a few time travel videos now, but this one is notable for its concise, intuitive explanation and visualization of our constant speed through spacetime (special relativity).
Everything in our universe moves at the speed of light through four dimensional spacetime. Your speed through spacetime is the sum of your separate speeds through time and space. It is impossible for you to stay still. Even if you are not moving through space dimensions, you are moving through the time dimension, blasting face first into the future.
You can slow down in the time dimension, by moving faster through the space dimensions but in total, you will always move at the speed of light through spacetime.
And you can “trade” moving through space for moving through time: “Move faster through space, go slower in time. Move slower through space, go faster in time.” Or as a commenter put it:
Your speed is constant. So the faster you move through the space dimensions, the slower you move through the time dimension, and vice versa.
Not sure this textual explanation makes as much sense as the visualization in the video, so maybe just watch that? Oh, and check out the sources for the video.
The Howtown crew explains how food manufacturers, the USDA, and food label services figure out how many calories are in the foods we eat. Spoiler: it’s not just a matter of burning food to see how much energy is produced — different nutrients are absorbed more or less efficiently by the body so you need to measure the output and compare it to the input.
And don’t forget to check the comments for Joss Fong’s banana oat blobs.
I’d missed that Time magazine is naming a “Kid of the Year” now and this year’s recipient is 15-year-old scientist Heman Bekele, who has developed a soap that could treat and even prevent skin cancer.
A few years ago, he read about imiquimod, a drug that, among other uses, is approved to fight one form of skin cancer and has shown promise against several more. Typically, imiquimod, which can help destroy tumors and usually comes in the form of a cream, is prescribed as a front-line drug as part of a broader cancer treatment plan, but Heman wondered if it could be made available more easily to people in the earliest stages of the disease. A bar of soap, he reckoned, might be just the delivery system for such a lifesaving drug, not just because it was simple, but because it would be a lot more affordable than the $40,000 it typically costs for skin-cancer treatment.
“What is one thing that is an internationally impactful idea, something that everyone can use, [regardless of] socioeconomic class?” Heman recalls thinking. “Almost everyone uses soap and water for cleaning. So soap would probably be the best option.”
Kurzgesagt explores what happens when a virus or bacteria enters a human body and the essential role fever plays in helping your body fight off disease.
Fever feels bad. So we take medication to suppress it — but is this a good idea? It turns out fever is one of the oldest defenses against disease. What exactly is a fever, and how does it make your immune defense stronger? Should you take a pill to combat it?
We often mistake fever for the disease…it’s actually part of the cure. When my kids were young, I vividly remember our laissez-faire French pediatrician urging us not to give them medication to get rid of their fevers because that was the body fighting back and doing useful work — unless their temps got too high of course.
This piece by Lydia Polgreen on The Strange Report Fueling the War on Trans Kids is so good — straightforward and informative, especially when compared to the incoherent nonsense that the NY Times has run about trans people over the past few years. The piece is about, in Polgreen’s words, “the sneaky effort to use what looks like science to justify broad intrusions in our personal freedom”.
I usually don’t do this, but I’ve excerpted the article’s conclusion here because it just gets right to the heart of an urgent concern: the freedom to control our own bodies.
Imagine that your health care required objective justification, if access to birth control or erectile dysfunction medications required proving that you were having monogamous sex, or good sex, or sex at all. Or if fertility care was provided only if you could prove that becoming a parent would make you happy, or you would be a good parent. Or that abortion would be available only if you could prove that it would improve your life.
In a free society we agree that these are private matters, decided by individuals and their families, with the support of doctors using mainstream medical science as a guide, even when they involve children. We invite politicians and judges into them at great peril to our freedom.
I encourage you to read the whole thing — it’s interesting throughout.
If you spend any amount of time on the internet — and if you’re reading this, you probably do and perhaps even feel shamed by your weekly Screen Time notification — you’ve probably seen the statistic that 5% of the Earth’s population is related to 13th century ruler of the Mongol Empire and presumed prolific father, Genghis Khan. In this episode of SciShow, Hank Green explores if that’s true and how researchers investigate relations across dozens and even hundreds of generations.
Using methods generally employed to track the evolution and spread of plants and animals over time and across geography, this paper aims to provide a scientific classification of Italian stuffed pasta shapes (pasta ripiena) and how they spread and evolved across what is now Italy. From the abstract of ‘Evolution of the Italian pasta ripiena: the first steps toward a scientific classification’:
Our results showed that, with the exception of the Sardinian Culurgiones, all the other pasta ripiena from Italy likely had a single origin in the northern parts of the country. Based on the proposed evolutionary hypothesis, the Italian pasta are divided into two main clades: a ravioli clade mainly characterized by a more or less flat shape, and a tortellini clade mainly characterized by a three-dimensional shape.
The introduction provides a short history lesson in stuffed foods:
The Italian pasta ripiena are part of a large family of Eurasian stuffed dumplings that similarly come in a wide array of shapes and forms and are known by many different names, for example, the Turkish manti, German maultaschen, Polish pierogi, Jewish kreplach, Russian pelmeni, Georgian khinkali, Tibetan momo, Chinese wonton, Japanese gyoza, and many others. It is unclear whether all dumplings had a singular origin or evolved independently, or how the remarkable diversity observed in Italy is related to the greater variation present in Eurasia. Based on linguistic similarities, it has been speculated that stuffed dumplings were probably first invented in the Middle East and subsequently spread across Eurasia by Turkic and Iranian peoples. Dumplings were known in China during the Han Empire (206 BC-220 AD), where archaeological remnants of noodles from this period were also discovered; however, in the same era, pasta had not yet made its appearance in Europe. The Italian ravioli have also been suggested to be a descendent of the Greek manti.
And then moves on to stuffed pastas native to Italy:
In Italy, ravioli are probably the oldest historically documented filled pasta, even though the early iterations of this dish evidently did not include the enclosing pasta casing. Between the 12 and 13 centuries, a settler from Savona agreed to provide his master with a lunch for three people made of bread, wine, meat and ravioli, during the grape harvest. Tortelli and agnolotti first appeared in literature much later. However, the origins of the iconic tortellini are controversial. The long-standing historical feud between the cities of Bologna and Modena over who invented the tortellini was symbolically settled at the end of the 19 century by Bolognese poet and satirist Giuseppe Ceri, who, in his poem “L’ombelico di Venere” (the navel of Venus), declared Castelfranco Emilia, a town halfway between the two cities, to be the birthplace of tortellini. According to this legend, one day, while Venus, Mars and Bacchus were visiting a tavern in Castelfranco Emilia, the innkeeper inadvertently caught Venus in a state of undress and was so astonished at the sight of the goddess’ navel that he ran into the kitchen and created tortellini in her honor. Clearly, a product as perfect as tortellini could be inspired only by Venus, the goddess of beauty.
See also How to Make 29 Different Shapes of Pasta by Hand, 150 Different Pasta Shapes, Flat-Packed Pastas That Pop Open When Cooked, and The Invention of a New Pasta Shape. (via @jenlucpiquant.bsky.social)
Ok, I did not know this, and it’s blowing my mind: we have been imaging exoplanets for such a long time that scientists have made time lapse movies of their motion around their stars. This one is a 12-year time lapse of four planets orbiting a star called HR 8799 (images from 2009-2021):
And this one of Beta Pictoris b covers a time period of 17 years (2003-2020):
HR 8799 is 133.3 light-years away from Earth and Beta Pictoris is 63.4 light-years away. That’s amazing! (via @philplait.bsky.social)
Andrea Pitzer, who wrote about about the history of concentration camps in her 2017 book One Long Night, has a piece in Scientific American about the historical parallels between Trump’s desire to expel as many as 20 million people from the country and previous concentration camps.
Trump’s plan to launch a massive deportation project nationwide — the first plank in the platform approved at his party’s convention — draws on the same flawed historical rationales and pseudoscience that built support for concentration camps worldwide in the 20th century. Early architects of these camps veiled their efforts in scientific terms while using terror and punishment to seize more power.
For example, Trump has claimed repeatedly that undocumented immigrants are “poisoning the blood” of the U.S. “Blood poisoning” is a medical condition; saying that foreigners are poisoning a nation’s blood is simply a slur. But perverting scientific or medical language to violate human rights and permit atrocities comes from a familiar playbook.
Again, this stuff is all right out in the open — no reading between the lines required.
In this video, Epic Spaceman takes us on a journey to the micro universe, shrinking himself by 10 times every 20 seconds or so until he’s the size of an atom, a journey that only took 10 steps. At each stage, he compares his size with a familiar object — quarter, blood cell, DNA helix — to keep us oriented.
It’s worth sticking around until the end of the video for an explanation of how exponential scales are always used to represent things like this and what it would look like if we used a linear scale instead. There is an unbelievable amount of empty space in matter.
John Green recently teamed up with Kurzgesagt for a video on one of the world’s deadliest diseases: tuberculosis.
The white death has haunted humanity like no other disease following us for thousands, maybe millions of years. In the last 200 years it killed a billion people — way more than all wars and natural disasters combined. Even today it’s the infectious disease with the highest kill count.
The maddening bit is that tuberculosis is curable…it’s just that the cure is not equally distributed around the world.
4,000 people died of tuberculosis yesterday, and we simply don’t have to accept a world where so many of us still die of a disease we know how to cure. The White Death has been with us for millions of years. It is time to continue our journey without it.
Kurzgesagt attempts to answer the question (from the perspective of physics): Do we have free will? Here’s the deterministic perspective (from the show notes):
Now imagine that if right after the Big Bang, a supersmart supercomputer looked at every single particle in the universe and noted all their properties. Just by applying the deterministic laws of physics, it should be able to predict what all the particles in existence would be doing until the end of time.
But if you are made of particles and it’s technically possible to calculate what particles will do forever, then you never decided anything. Your past, present and future were already predetermined and decided at the Big Bang. This would mean there is a kind of fate and you are not free to decide anything.
You may feel like you make decisions, but you are on autopilot. The motions of the particles that make up your brain cells that made you watch this video were decided 14 billion years ago. You are just in the room when it happens. You are only witnessing how the universe inside you unfolds in real time.
And the other side of the argument (in favor of free will):
We know that we can reduce everything that exists to its basic particles and the laws that guide them. While this makes physics feel like the only scientific discipline that actually matters, there is a problem: You can’t explain everything in our universe only from particles.
One key fact about reality that we can’t explain by looking just at electrons and quantum stuff is emergence. Emergence is when many small things together create new fundamental traits that didn’t exist before.
Emergence occurs at all levels of reality, and reality seems to be organized in layers: atoms, molecules, cells, tissues, organs, you, society. Put many things in one layer together and they’ll create the next layer up. Every time they do, entirely new properties emerge.
Having thought about this for all of 20 minutes (or, practically all of my life), the emergence argument against determinism makes a lot of sense to me. Then again, James Gleick’s Chaos and Steven Johnson’s Emergence both made a huge impression on me when I read it more than 20 years ago.
How do we know how dogs see? Are they colorblind? Nearsighted? How do they perceive movement? Does their excellent sense of smell help dogs see? The first episode of Howtown from Adam Cole & Joss Fong is all about dog vision and is predictably fascinating.
Kurzgesagt is back with another video about black holes; it has the innocuous-seeming title of The Easiest Way To Build a Black Hole. But the main topic of the video is the speculation that universes (like ours!) might exist within black holes.
Black holes might create infinite universes while destroying time and space. Everything in existence could be black holes, all the way down. We might live inside a black hole that is inside a black hole, that is inside a black hole. But let’s start at the beginning and build a black hole out of air.
This one is a bit of a brain-bender. From the show notes:
The first part of the script is based on the empirical fact that, somewhat intriguingly, the observable universe seems to have the exact size and mass that would be required to make a black hole as big as the observable universe itself.
The second, completely independent proposal we explore is the idea that our Universe could be born from the singularity of a black hole, and that in turn the universe that contains that black hole could be born from a black hole itself. If so, universes in later generations of this process could be better fitted to produce an abundance of black holes, in a sort of “natural selection” towards efficient black hole production.
You may have heard that this year, for the first time since 1803, two different broods of cicadas will emerge at the same time.
This year, though, will be a rare event. Two groups, or “broods,” are waking up during the same season. There will likely be billions, if not trillions, of the insects.
There’s the 17-year-group called Brood XIII, which is concentrated in northern Illinois (brown on the map below), and the 13-year clutch, Brood XIX, which will emerge in southern Illinois, Missouri, Arkansas, and throughout the Southeast.
You may have noticed the lengths of both periodicities (13, 17) are prime numbers — and that does not appear to be a coincidence. Scientists haven’t nailed down an exact cause, but one hypothesis has to do with predator cycles:
According to the paleontologist Stephen J. Gould, in his essay “Of Bamboo, Cicadas, and the Economy of Adam Smith,” these kind of boom-and-bust population cycles can be devastating to creatures with a long development phase. Since most predators have a two-to-ten-year population cycle, the twelve-year cicadas would be a feast for any predator with a two-, three-, four-, or six-year cycle. By this reasoning, any cicada with a development span that is easily divisible by the smaller numbers of a predator’s population cycle is vulnerable.
Prime numbers, however, can only be divided by themselves and one; they cannot be evenly divided into smaller integers. Cicadas that emerge at prime-numbered year intervals, like the seventeen-year Brood II set to swarm the East Coast, would find themselves relatively immune to predator population cycles, since it is mathematically unlikely for a short-cycled predator to exist on the same cycle. In Gould’s example, a cicada that emerges every seventeen years and has a predator with a five-year life cycle will only face a peak predator population once every eighty-five (5 x 17) years, giving it an enormous advantage over less well-adapted cicadas.
See also Long-lived insects raise prime riddle.
NASA used one of their supercomputers to model what it would look like if you flew into a supermassive black hole. (You can watch the simulation in a 360° view on YouTube. I bet it looks great on a VR rig like Apple Vision Pro.)
The movies begin with the camera located nearly 400 million miles (640 million kilometers) away, with the black hole quickly filling the view. Along the way, the black hole’s disk, photon rings, and the night sky become increasingly distorted — and even form multiple images as their light traverses the increasingly warped space-time.
In real time, the camera takes about 3 hours to fall to the event horizon, executing almost two complete 30-minute orbits along the way. But to anyone observing from afar, it would never quite get there. As space-time becomes ever more distorted closer to the horizon, the image of the camera would slow and then seem to freeze just shy of it. This is why astronomers originally referred to black holes as “frozen stars.”
At the event horizon, even space-time itself flows inward at the speed of light, the cosmic speed limit. Once inside it, both the camera and the space-time in which it’s moving rush toward the black hole’s center — a one-dimensional point called a singularity, where the laws of physics as we know them cease to operate.
“Once the camera crosses the horizon, its destruction by spaghettification is just 12.8 seconds away,” Schnittman said. From there, it’s only 79,500 miles (128,000 kilometers) to the singularity. This final leg of the voyage is over in the blink of an eye.
Black holes: so cool. (via the kid should see this)
Is the periodic table yummy? Well, it depends on the element. But if you’ve ever wondered if a little taste of xenon or iridium would do you any harm, this periodic table is for you.
See also What If You Swallowed All Elements of the Periodic Table?. (via @anewplacetohide)
Steve Mould’s videos are always entertaining and informative but this one is also a little bit mind-blowing. If you build a circular trough with just the right dimensions and fill it with lighter fluid, a flame will travel around it. And other shapes will do other things — the effect created by the star/octopus shape is especially cool. The effect is an example of an excitable medium:
An excitable medium is a nonlinear dynamical system which has the capacity to propagate a wave of some description, and which cannot support the passing of another wave until a certain amount of time has passed (known as the refractory time).
A forest is an example of an excitable medium: if a wildfire burns through the forest, no fire can return to a burnt spot until the vegetation has gone through its refractory period and regrown.
Other examples:
Normal and pathological activities in the heart and brain can be modelled as excitable media. A group of spectators at a sporting event are an excitable medium, as can be observed in a Mexican wave (so-called from its initial appearance in the 1986 World Cup in Mexico).
(via waxy)
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