Dust devils, like fire tornadoes and waterspouts, form from warm, rising air. As the sun heats the ground to temperatures hotter than the surrounding atmosphere, hot air will begin to rise. When it rises, that air leaves behind a region of lower pressure that draws in nearby air. Any vorticity in that air gets intensified as it gets pulled toward the low pressure area. It will start to spin faster, exactly like a spinning ice skater who pulls in his arms. The result is a spinning vortex of air driven by buoyant convection. On Earth, dust devils are typically no more than a few meters in size and can only pick up light objects like leaves or hay. On Mars, dust devils can be hundreds of meters tall, and, though they’re too weak to do much damage, they have helpfully cleaned off the solar panels of some of our rovers! (Image credit: T. Bargman, source; via Gizmodo)
We already know that spider silk is something of a wonder material, but scientists are still discovering more awesome things that it can do. An international team of researchers has found that spider silk shares a useful property with semiconductors—except rather than exploiting this to manipulate electrons, it can be used to manipulate sound and heat.
As described in a new paper in Nature Materials, spider silk can block certain quasiparticles of sound (called “phonons”), depending on their frequency, the same way semiconductors can block certain electrons. “There’s a range of frequencies that are not allowed to propagate,” co-author Edwin Thomas of Rice University said in a statement. “If you broadcast sound at a particular frequency, it won’t go into the material.”
It’s known as a band gap, and it’s what lets scientists effectively “tune” materials with this property for specific applications. Photonic crystals—opals are a naturally occurring example—do this for light waves. Phononic crystals do the same for sound, but this is the first time anyone has found such a band gap in this kind of material.
‘Memba them .gifs?! Had to design myself some business cards and this one for arctan(z), z∈[0, 2π], ended up being the inspiration for the backs of ‘em, and then when I got home earlier from my near-daily failed attempt at getting shit done for my class at a coffee shop in town, I made my first go at… something? conformal mapping-esque as a concertina card using the same thing but with 15 contours instead of 26 since that’d be a total shitshow. (This isn’t a conformal map, this a contour map of the real/blue and imaginary/red parts, whatever, but it’s around the same level of intricacy probably.) Unfortunately I was kind of sloppy in making my Adobe Illustrator cut pattern because THE INSPIRATION WAS COMING TOO HARD TOO FAST so the fold wasn’t centered, but oh well. I also had to do a lot of post-op manual Xacto assistance because I still haven’t gotten the hang of this machine. First time coloring one of the machine-cut ones, too. It’s curled worse than any of my hand-cut ones, gonna blame the cardstock. I’m about to try and get some of this homework done before I go disappoint my complex teacher with how little I’ve accomplished tomorrow and then I think I’mma finally give doing long strips of Bristol a whirl.
Also that was not the final version of the front of my business cards, that’s an older iteration without my phone number. Also also it makes me super happy that my logo font is Euclid, the contact info is Gravity. Ha. (And sometime between now and when I leave, I’ve gotta get an actually-professional portfolio site up, gah. STRESSIN’. And procrastinating. By doing more art projects. Sorry not sorry.)
hi! In this master post (inspired by @denistudiespost on science youtube channels), I’m going to list and briefly explain STEM(science, technology, engineering and mathematics) you tubers, podcasts, tumblrs, shows, and sites that can be for school and/or your own curiosity! note: not all of these things directly pertain to stem, so this may not exactly help you with schoolwork, but if you’re interested in stem, check these out and learn a lil’ bit more today!
SciShow: Hosted by a slew of youtubers, this short show gives very cool answers to very cool science questions that you’d never think to ask.
MinutePhysics: If you’re a visual learner, I’d definitely check this one out. This channel answers sometimes complicated physics questions simply with the addition of drawings.
AsapSCIENCE: I don’t even know how to describe this one, guys. It’s somewhatley in a similar style to MinutePhysics, but with a different approach. Definitely very neat!
thebrainscoop: This is a youtube channel lead by Emily Graslie at the Field Museum and is very cool and a very nice resource for natural sciences and biology! She’s also one of the few female youtubers I see in STEM, and she made a bomb video addressing that(find it here).
TED-Ed: This is such a fave. On this channel, TED partners educators and animators to make a video and a lesson on a particular topic, ranging from riddles to physics to language.
Khan Academy: Wonderful for help with math, physics, and even history(they also have a website, which I’ll talk about later)!
Physics Girl: Another woman in STEM! This channel is a personal favorite, she does a really good job with explaining physics.
Podcasts(I’m a nerd but bear with me):
Invisibilia: A podcast about psychology. They’re currently in the middle of their second season, so there are plenty of new episodes!
Radiolab: This podcast covers everything from supreme court cases and social shifts to the physics behind shrimp snapping, which might sound ridiculous, but I promise you it’s wonderful. There are tons of episodes- I highly recommend the older episodes, and they’re longer and stay more on the science track.
StarTalk Radio: Hosted by Neil DeGrasse Tyson, this podcast goes into different branches of physics in immense detail, but I promise it’s not boring cuz it’s PHYSICS.
Science Friday: Essentially covers everything within STEM and is also my favorite part of NPR each week, because how could it not?
NASACast: For my fellow space people, this is a summary of what’s the haps at NASA! I had no idea that this was a thing and it’s great!
@prxstem - everything you could ever wish for in a stem tumblr in one place.
@nasa - Your daily dose of space and other cool science things.
@skunkbear - NPR’s science tumblr. It does not disappoint.
Most studyblrs also have STEM resources and there are so many other science-dedicated tumblrs, these are just a few of my favorites!
Khan Academy: This website entails math, science, and history help for grades 2-12(I believe the math program goes up through calculus). It offers videos you can learn from and then practice problems for you to do- sort of like a textbook, except you skip the reading part.
The Biology Corner: Everything that even remotely entails biology, from evolution to anatomy.
Gizmo: Most schools only use this with a membership and it’s most commonly used in Jr. High, but it has super useful online lab simulations that help you learn by doing!
Exploratorium: THIS IS SO COOL. I highly encourage also following them on instagram for even more cool things, but the exploratorium is an interactive museum in San Fransisco and their website has plenty of guides on STEM experiments that you can do at home!
Ask A Science Teacher by Larry Scheckel- This book answers almost every question you could thing of that even remotely pertains to any area of science. Very cool and a good book to just keep around! Buy it here.
What if? by Randall Monroe- This book, which is also lovely-ly illustrated, gives serious scientific answers to absurd hypothetical situations and is a great and hilarious read that will actually teach you some stuff along the way. Buy it here.
Thing Explainer, also by Randall Monroe- Someone wise once said that you must know a topic well enough to explain it simply and I can’t remember that wise person’s name, but y'all get the point. Thing Explainer only uses the 1,000 most commonly used words in the English language to explain complicated things, like space! Buy it here.
A Brief History of Time by Stephen Hawking- This book made me ponder and question my existence for hours on end- that being said, if you want to go into a scientific field, READ THIS BOOK. Buy it here.
That’s that! If there’s a resource that’s not on here but would be helpful to you, shoot me an ask on the topic and I’ll find something and add it!
The nature of the future is completely different from the nature of the past. When quantum effects are significant, the future shows all the signs of quantum weirdness, including duality, uncertainty, and entanglement. With the passage of time, after the time-irreversible process of state-vector reduction has taken place, the past emerges, with the previous quantum uncertainty replaced by the classical certainty of definite particle identities and states. The present time is where this transition largely takes place, but the process does not take place uniformly: evidence from delayed choice and related experiments shows that isolated patches of quantum indeterminacy remain, and that their transition from probability to certainty only takes place later. Thus, when quantum effects are significant, the picture of a classical Evolving Block Universe (‘EBU’) cedes place to one of a Crystallizing Block Universe (‘CBU’), which reflects this quantum transition from indeterminacy to certainty, while nevertheless resembling the EBU on large enough scales.
George F. R. Ellis & Tony Rothman, Time and Spacetime: The Crystallizing Block Universe
Nikola Tesla does not believe in the existence of an “electron” as pictured by pop science — or, he maintains, through practical reasoning and experimentation, that if it can exist at all, it does so only in perfect vacuum.
“To account for its apparently small mass, science conceives the electron as a hollow sphere, a sort of bubble. Now, a bubble can exist in such a medium as a gas or liquid because its internal pressure is not altered by deformation. But if, as supposed, the internal pressure of an electron is due to the repulsion of electric masses, the slightest conceivable deformation must result in the destruction of the bubble!
“Just to mention another improbability, the force tending to tear an electron apart is, in pounds per square inch, represented by the staggering figure of 256,899 followed by twenty-one zeros — and this is 513,798,000,000,000,000,000 times greater that the tension that tungsten wire can withstand! And yet it does not burst! Not even when it is hurled against an obstacle with a speed hundreds of thousands times greater than that of a bullet!”
“A Famous Prophet of Science Looks Into the Future.”Popular Science Monthly, November, 1928.
“Up to 1896, however, I did not succeed in obtaining a positive experimental proof of the existence of such a medium. But in that year I brought out a new form of vacuum tube capable of being charged to any desired potential, and operated it with effective pressures of about 4,000,000 volts. I produced cathodic and other rays of transcending intensity. The effects, according to my view, were due to minute particles of matter carrying enormous electrical charges, which, for want of a better name, I designated as matter not further decomposable. Subsequently those particles were called electrons.”
“Nikola Tesla Tells of New Radio Theories.”New York Herald Tribune, September 22, 1929.
“The idea of the atom being formed of electrons and protons which go whirling round each other like a miniature sun and planets is an invention of the imagination, and has no relation to the real nature of matter.
“Virtually all progress has been achieved by physicists, discoverers and inventors; in short, devotees of the science which Newton and his disciples have been and are propounding.
“Personally, it is only efforts in this direction which have claimed my energies. Similar remarks might be made with respect to other modern developments of thought. Take, for example, the electron theory. Perhaps no other has given rise to so many erroneous ideas and chimerical hopes. Everybody speaks of electrons as something entirely definite and real. Still, the fact is that nobody has isolated it and nobody has measured its charge. Nor does anybody know what it really is.
“In order to explain the observed phenomena, atomic structures have been imagined, none of which can possibly exist.
“My ideas regarding the electron are at variance with those generally entertained. I hold that it is a relatively large body carrying a surface charge and not an elementary unit. When such an electron leaves an electrode of extremely high potential and in very high vacuum, it carries an electrostatic charge many times greater than the normal. This may astonish some of those who think that the particle has the same charge in the tube and outside of it in the air. A beautiful and instructive experiment has been contrived by me showing that such is not the case, for as soon as the particle gets out into the atmosphere it becomes a blazing star owing to the escape of the excess charge. The great quantity of electricity stored on the particle is responsible for the difficulties encountered in the operation of certain tubes and the rapid deterioration of the same.”
“Dynamic Theory Of Gravity.“ July 10, 1937 (Prior to interviews with the press on his 81st birthday observance).
“Before the electron theory was advanced, I had established that radio-active rays consisted of particles of primary matter not further decomposable, and the first thing to find out was whether the sun is charged to a sufficiently high potential to produce the effects noted. This called for a prolonged investigation which culminated in my discovery that the sun’s potential was 216,000,000,000 volts and that all such large and hot bodies emit cosmic rays.
“While the origin and character of the rays observed near the earth’s surface had thus been sufficiently well ascertained, the so-called cosmic rays observed at great altitudes presented a riddle for more than twenty-six years, chiefly because it was found they increased with the height at a rapid rate. My investigations brought out the astonishing fact that the effects at high altitude are of an entirely different nature, having no relation whatever to cosmic rays. These are particles from celestial bodies at very high temperatures and charged to enormous electrical potentials.
“The effects at great elevations are due to waves of extremely small lengths produced by the sun in a certain region of the atmosphere. THIS IS THE DISCOVERY I WISH TO MAKE KNOWN. The process involved in the generation of the waves is the following: The sun projects charged particles constituting an electric current which passes through a conducting stratum of the atmosphere approximately ten kilometers (six miles) thick enveloping the earth. This is a transmission of electrical energy exactly as I illustrated in my experimental lecture in which one end of a wire is connected to an electric generator of high potential, its other end being free. In this case the generator is represented by the sun and the wire by the conducting air.”
“The passage of solar current involves the transference of electric charges from particle to particle with the speed of light, resulting in the production of extremely short and penetrating waves. As the air stratum mentioned is the source of the waves it follows that the so-called cosmic rays observed at great altitude must increase as this stratum is approached.”
“In The Realm Of Science: Tesla, Who Predicted Radio, Now Looks Forward To Sending Waves To The Moon.”New York Herald Tribune, Aug. 22, 1937.
Please note that I have included the descriptions of the planets on the pictures, so that you don’t have to keep scrolling up and down. All you have to do is click on them to read the description.
1. J1407b - Although it physically resembles Saturn, J1407b is much smaller than Saturn is, and has a much larger ring system.
2. TrEs-2b - Also known as the Dark Planet, TrEs-2b is officially the darkest planet in the known universe. It reflects less than 1% of light, and they say that it is so dark that even coal seems brighter than it.
3. 55 Cancri E - Also known as the Planet of Diamonds, at twice the size of Earth 55 Cancri E is so dense and carbon-heavy that the carbon has been compressed into a diamond.
4. Gliese 436b - Although the planet is similar in size to Neptune, it is too dense to be composed largely of hydrogen (as most gas giants are). Scientists believe that instead it is made up of a large concentrate of hot water ice (also known as “Ice-x”).
5. WASP-12b - This planet rotates so close to its parent star that it only has about another ten million years before it’s completely devoured.
6. Titan - This one isn’t a planet; it isn’t even outside of our Solar System. Titan is the largest moon that orbits Saturn, and is the only place outside of Earth where clear evidence of liquid has been found. The difference is that while the liquid on Earth is mostly composed of water, the liquid on Titan is actually methane.
7. Gliese 1214b - Scientists have nicknamed this planet ‘Waterworld’ due to it being the most likely contender outside of our Solar System to contain liquid water.
8. TrES-4b - Aside from WASP-12b, TrES-4b is one of the largest exoplanets ever found - this is a size comparison of TrES-4b to Jupiter.
9. HD 188753 - Also known as “Hot Jupiter”, this exoplanet is so hot and so large that it has actually challenged the currently accepted theory of gas planet formation. According to prevailing scientific theories, a gas planet this hot should not be able to exist.
10. HD 189733b - A gas giant with a daytime temperature of about 2,000 degrees Farenheit (1093 C), according to NASA, HD 189733b rains liquid glass sideways amid 4,500 mph winds.
A recent viral video features mesmerizing footage of a giant octopus kite flown at a kite festival in Singapore earlier this month. The kite’s arms twist and wave lazily in the breeze. Watching the video, I was struck by how realistic the kite’s motion looks. It really looks like an octopus is just cruising there in mid-air. And that resemblance might not be accidental.
In fluid dynamics, scientists often use a concept called dynamic similitude to test the physics of a scale model instead of the full-size original. The simplest version of this uses the Reynolds number to compare the model and the original. The Reynolds number is a dimensionless number that depends on the object’s size, the flow’s speed, and the density and viscosity of the fluid. If you match the scale model’s Reynolds number to the original’s Reynolds number, then the physics will be the same – even if you changed the fluid or the size of the object.
Returning to our kite, one thing the footage doesn’t entirely convey is just how enormous this kite really is. The Straits Times reports the kite is about the length of five buses and requires six people to get aloft. But the kite’s size helps compensate for the fact that it’s flying in air instead of swimming through viscous water like a real octopus. Although I’m left estimating the kite’s size and the wind’s speed, my quick calculations put the Reynolds numbers for the kite and the octopus on the order of 10,000. So, strange as it seems, this giant kite really is acting like a swimming octopus!
(Image credits: E. Chew, source)
A human brain has around 86 billion neurons, and the communication between these neurons are constant. The sheer scale of these interactions mean a computer (an EEG) can register this electrical activity, with different frequencies indicating different mental states.