Is tar roads better than roman? If westros had tar would travel be faster than the dirt/cobbled they have?
Tar roads are so much better than cobbled roads and both are far superior to dirt roads. The problem is that for the most part, you can't really make a large amount of petroleum tar in the medieval era - primarily the medieval era used wood tar which had a wide variety of uses from caulking to a crude incendiary weapon.
In 1930 the Indiana Bell building was rotated 90°. Over 34 days, the 22-million-pound structure was moved 15 inch/hr... all while 600 employees still worked there. There was no interruption to gas, heat, electricity, water, sewage, or the telephone service they provided. No one inside felt it move.
if you want to know how stupid elon musk is, for the aesthetics, he painted his space x cold box black. they are always painted white because they aren't trying to absorb heat.
they are essentially giant coolers. they keep cryogenic gases and liquids cold. so he made it more inefficient. like, what a dumb ass. he made his cold box a hot box in fucking texas.
it's so thermally inefficient and he is what nerds think is someone you want sending ppl to space??? really??? he'll fuck you over for aesthetics while losing more money in the process. and the math is wrong
Controlling storm water is a major challenge in urban environments, where many surfaces are impermeable. In a city, rain cannot simply soak into the ground and filter into the water table. Enter permeable pavement! (Image and video credit: Practical Engineering)
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Curious about how to send research to the International Space Station or how to get involved with NASA missions as a college student? Ask our experts!
Through our Student Payload Opportunity with Citizen Science, or SPOCS, we’re funding five college teams to build experiments for the International Space Station. The students are currently building their experiments focusing on bacteria resistance or sustainability research. Soon, these experiments will head to space on a SpaceX cargo launch! University of Idaho SPOCS team lead Hannah Johnson and NASA STEM on Station activity manager Becky Kamas will be taking your questions in an Answer Time session on Thurs., June 3, from 12-1 p.m. EDT here on our Tumblr! Make sure to ask your question now by visiting http://nasa.tumblr.com/ask.
Hannah Johnson recently graduated from the University of Idaho with a Bachelor of Science in Chemical Engineering. She is the team lead for the university’s SPOCS team, Vandal Voyagers I, designing an experiment to test bacteria-resistant polymers in microgravity. Becky Kamas is the activity manager for STEM on Station at our Johnson Space Center in Houston. She helps connect students and educators to the International Space Station through a variety of opportunities, similar to the ones that sparked her interest in working for NASA when she was a high school student.
Student Payload Opportunity with Citizen Science Fun Facts:
Our scientists and engineers work with SPOCS students as mentors, and mission managers from Nanoracks help them prepare their experiments for operation aboard the space station.
The Vandal Voyagers I team has nine student members, six of whom just graduated from the Department of Chemical and Biological Engineering. Designing the experiment served as a senior capstone project.
The experiment tests polymer coatings on an aluminum 6061 substrate used for handles on the space station. These handles are used every day by astronauts to move throughout the space station and to hold themselves in place with their feet while they work.
The University of Idaho’s SPOCS project website includes regular project updates showing the process they followed while designing and testing the experiment.
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Time for another science post! As usual, you can read more about fusion reactors under my #fusion tag! Let’s talk about…
Tokamaks vs Stellarators!
These devices work on the same general principle: take a very hot plasma, and confine it in a loop using powerful magnets. Heat up the plasma enough and it starts to fuse, then harvest the resulting neutrons to generate electricity. But there’s a catch!
You can’t just have the plasma move around in a circle. If you did that, negative and positive particles would drift in opposite directions, collide with the walls of the chamber, and fizzle out. Instead, you need to get everything moving in a helix.
The difference between a stellarator and a tokamak lies in how they generate that helix.
This is a tokamak! The vast majority of fusion reactors out there use this design. They work by having a torus (donut-shaped) plasma, with spiraling magnetic fields traveling through it. Within the toroidal plasma, particles follow the helical field lines.
The way you generate this helical field is pretty dang clever. What you do is take two perpendicular magnetic fields — one poloidal (looping in and out of the donut hole), and one toroidal (around the donut in a circle) — and add them together. The resulting combined field is a helix!
The toroidal field is “easiest” to generate. You have a series of powerful magnets that form a ring around the torus. They create a powerful magnetic field in the toroidal direction.
The poloidal field is trickier. For that one, you use a big transformer coil that sits in the middle of the “donut hole.” By ramping up the current in the transformer, you induce a corresponding current within the plasma itself. That plasma current in turn produces its own magnetic field, in the poloidal direction. Toroidal + poloidal = helical.
This is a stellarator! Or rather, one kind of stellarator. Rather than having a torus-shaped plasma with a helical magnetic field running through it, you just make the plasma itself into a helix! You use toroidal magnets (weird blue shapes above) to contain it and drive it along, without the need to generate any plasma current at all. This results in some incredibly wacky geometries!
So which is better?
That’s not an easy question to answer. Let’s compare pros and cons.
Simple geometry, symmetric all around.
Design is forgiving to small errors.
We’ve been building them for 50 years and have gotten pretty good at it.
Every toroidal magnet is identical. Manufacturing the machine is relatively cheap.
Extremely dense plasma that produces a ton of energy.
Plasma current induced by a transformer is inherently transient. If you want to run “steady state” (I.e. for more than 30 seconds), you need to have other ways of keeping that current going. This is doable with various techniques called “current drive,” but it’s tricky. KSTAR and EAST are two tokamaks that are very good at this.
If the plasma collides with the walls of the machine, the entire plasma current gets dumped into one spot. You get what’s called a “halo current,” where several mega amps of electricity blast through an area maybe 10 centimeters wide in a few milliseconds. This is called a “disruption event.” They happen a lot, and they give the machine a hell of a beating.
No need for plasma current! This means you can just run steady state pretty much indefinitely.
No plasma current means that disruptions are relatively gentle, when they happen at all.
As opposed to a tokamak, there are a lot of potential stellarator configurations. Before modern computers, trying to calculate a good stellarator magnet geometry was all but impossible.
They are extremely difficult and expensive to build. Every magnet is unique, and the Seussian vacuum chamber itself is a nightmare to engineer.
Stellarator plasmas are generally colder, and not as dense.
Given how difficult they’ve been to design, we just haven’t built many stellarators. Stellarator research is 30 years behind tokamak research.
So which is best? Nobody really knows! Judging by the trends in research, the first fusion power plant will almost certainly be a tokamak. But hey, it’s possible that eventually, stellarators will become the industry standard.
And now to finish it off, here are some pictures inside the two biggest stellarators in the world: LHD (the Large Helical Device) in Japan, and Wendelstein 7-X in Germany! They are confusing and hard to look at, and have very different geometries.
Got distracted and I converted an old camera to full-spectrum, making good on this post.
It's an old Canon SX110 IS, mid-range point and shoot from around 2008. My main pocket camera is a descendant of this.
didn't get a lot of photos of the disassembly because i was hurrying a bit (which hurt me later, we'll get there) but disassembly was surprisingly smooth. A few adventures with supplying power to the lens motor just to get it to retract fully but nothing big. Managed to get the filter out with minimal fuss.
It's a tiny piece of dichroic glass that was sandwiched in the sensor assembly. Most cameras have at least one basic filter to cut out UV, IR or both.
Here's some comparison photos after removing it: It looks like these otherwise black mousepads are made of an IR reflecting material, glowing purple under ambient IR, which is different from the black powder-coat of the desk, which seems to absorb near-IR just as much as visible light. I wonder if that's so that modern infrared based mouse sensors can see better. Probably!
Reassembly was where things got messy: I didn't notice the motor control ribbon get disconnected and so I futzed around a while before I solved that, and putting that in involves removing the mainboard from the chassis. I forgot to plug the mainboard back into power when I reassembled it, and while jiggling some connections I tore through the ribbon cable that connects the shutter, power, and mode control group to the mainboard. Fuck ribbon cables, all my homies hate ribbon cables
Fortunately, I can still get the thing to power on by shorting some easily accessible bare copper on the board (which is how I got those verification shots), and the part that got damaged should be easy to replace: all I need is a donor camera. There's someone selling one on Marketplace for a reasonable price, and I'll put out a call on the local used tech forum as well.
Next steps would be finding some Visible, UV and IR filters so I can select particular regions of the spectrum, and probably a couple band-pass filters for looking at vegetation and so on. With an adequate filter setup (maybe I'll get a filter holder printed) and the CHDK firmware mod for this camera, I'll be able to stick it on a tripod and capture some of those dreamy snow-white foliage pics all the infrared photographers love so much.
This was a pretty finicky operation so all in all I'm pretty happy that I only broke one easily replaceable part. If I hadn't been able to get this powered on I probably wouldn't have been willing to put out the expense for a part replacement. Not bad for maybe an hour and a half's work.
1. Marie Curie (Maria Salomea Skłodowska Curie, 7 November 1867 – 4 July 1934), was a Polish and naturalized-French physicist and chemist who conducted pioneering research on radioactivity - a term she coined. She discovered the elements polonium and radium, using techniques she invented for isolating radioactive isotopes. During World War I she developed mobile radiography units to provide X-ray services to field hospitals. She was the first woman to win a Nobel Prize and the only person to win the Nobel Prize in two scientific fields. She was the first woman to become a professor at the University of Paris in 1906.
"Nothing in life is to be feared, it is only to be understood. Now is the time to understand more, so that we may fear less."
2. Ada Lovelace (Augusta Ada King, Countess of Lovelace, 10 December 1815 – 27 November 1852) was an English mathematician and writer, chiefly known for her work on Charles Babbage's proposed mechanical general-purpose computer, the Analytical Engine. She was the first to recognise that the machine had applications beyond pure calculation, and to have published the first algorithm intended to be carried out by such a machine. As a result, she is often regarded as one of the first computer programmers.
"Mathematical science shows what is. It is the language of unseen relations between things. But to use and apply that language, we must be able to fully appreciate, to feel, to seize the unseen, the unconscious."
3. Rosalind Franklin (Rosalind Elsie Franklin, 25 July 1920 – 16 April 1958) was an English chemist and X-ray crystallographer whose work was central to the understanding of the molecular structures of DNA (deoxyribonucleic acid), RNA (ribonucleic acid), viruses, coal, and graphite. Franklin is best known for her work on the X-ray diffraction images of DNA while at King's College London, particularly Photo 51, which led to the discovery of the DNA double helix for which Francis Crick, James Watson, and Maurice Wilkins shared the Nobel Prize in Physiology or Medicine in 1962.
"You look at science (or at least talk of it) as some sort of demoralising invention of man, something apart from real life, and which must be cautiously guarded and kept separate from everyday existence. But science and everyday life cannot and should not be separated. Science, for me, gives a partial explanation for life. In so far as it goes, it is based on fact, experience and experiment."
4. Grace Hopper (Grace Brewster Murray Hopper, December 9, 1906 – January 1, 1992) was an American computer scientist and United States Navy rear admiral. One of the first programmers of the Harvard Mark I computer, she was a pioneer of computer programming who invented one of the first linkers. Hopper was the first to devise the theory of machine-independent programming languages, and the FLOW-MATIC programming language she created using this theory was later extended to create COBOL, an early high-level programming language still in use today.
"The only phrase I’ve ever disliked is, 'Why, we’ve always done it that way.' I always tell young people, 'Go ahead and do it. You can always apologize later.'"
5. Hypatia of Alexandria (350–370 - 415 AD) was a Hellenistic Neoplatonist philosopher, astronomer, and mathematician, who lived in Alexandria, Egypt, then part of the Eastern Roman Empire. She was a prominent thinker of the Neoplatonic school in Alexandria where she taught philosophy and astronomy. She is known to have written a commentary on Diophantus's thirteen-volume Arithmetica, which may survive in part, having been interpolated into Diophantus's original text, and another commentary on Apollonius of Perga's treatise on conic sections, which has not survived. Many modern scholars also believe that Hypatia may have edited the surviving text of Ptolemy's Almagest, based on the title of her father Theon's commentary on Book III of the Almagest. Hypatia is known to have constructed astrolabes and hydrometers.
"Fables should be taught as fables, myths as myths, and miracles as poetic fancies. To teach superstitions as truths is a most terrible thing. The child mind accepts and believes them, and only through great pain and perhaps tragedy can he be in after years relieved of them. In fact, men will fight for a superstition quite as quickly as for a living truth—often more so, since a superstition is so intangible you cannot get at it to refute it, but truth is a point of view, and so is changeable."
6. Lise Meitner ( 7 November 1878 – 27 October 1968) was an Austrian-Swedish physicist who contributed to the discoveries of the element protactinium and nuclear fission. While working at the Kaiser Wilhelm Institute on radioactivity, she discovered the radioactive isotope protactinium-231 in 1917. In 1938, Meitner and nephew-physicist Otto Robert Frisch discovered nuclear fission. They found that bombarding thorium with neutrons produced different isotopes. Hahn and Strassmann later in the year showed that isotopes of barium could be formed by bombardment of uranium. In late December, Meitner and Frisch worked out the phenomenon of such a splitting process. In their report in February issue of Nature in 1939, they gave it the name "fission". This principle led to the development of the first atomic bomb during World War II, and the subsequently other nuclear weapons and nuclear reactors. However, she did not share the 1944 Nobel Prize in Chemistry for nuclear fission, which was awarded exclusively to her long-time collaborator Otto Hahn. She was praised by Albert Einstein as the "German Marie Curie".
"Science makes people reach selflessly for truth and objectivity; it teaches people to accept reality, with wonder and admiration, not to mention the deep awe and joy that the natural order of things brings to the true scientist."
7. Katherine Johnson (Creola Katherine Johnson, August 26, 1918 – February 24, 2020) was an American mathematician whose calculations of orbital mechanics as a NASA employee were critical to the success of the first and subsequent U.S. crewed spaceflights. Johnson's work included calculating trajectories, launch windows, and emergency return paths for Project Mercury spaceflights, including those for astronauts Alan Shepard, the first American in space, and John Glenn, the first American in orbit, and rendezvous paths for the Apollo Lunar Module and command module on flights to the Moon. Her calculations were also essential to the beginning of the Space Shuttle program, and she worked on plans for a mission to Mars. In 2015, President Barack Obama awarded Johnson the Presidential Medal of Freedom.
"The women did what they were told to do. They didn’t ask questions or take the task any further. I asked questions; I wanted to know why. They got used to me asking questions and being the only woman there."
8. Nettie Stevens (Nettie Maria Stevens, July 7, 1861 – May 4, 1912) was an American geneticist who discovered sex chromosomes. In 1905, soon after the rediscovery of Mendel's paper on genetics in 1900, she observed that male mealworms produced two kinds of sperm, one with a large chromosome and one with a small chromosome. When the sperm with the large chromosome fertilized eggs, they produced female offspring, and when the sperm with the small chromosome fertilized eggs, they produced male offspring. The pair of sex chromosomes that she studied later became known as the X and Y chromosomes.
9. Margaret Hamilton (Margaret Heafield Hamilton, born August 17, 1936) is an American computer scientist, systems engineer, and business owner. She was director of the Software Engineering Division of the MIT Instrumentation Laboratory, which developed on-board flight software for NASA's Apollo program. She later founded two software companies—Higher Order Software in 1976 and Hamilton Technologies in 1986, both in Cambridge, Massachusetts. Hamilton has published more than 130 papers, proceedings and reports about sixty projects and six major programs. She is one of the people credited with coining the term "software engineering". On November 22, 2016, Hamilton received the Presidential Medal of Freedom from president Barack Obama for her work leading to the development of on-board flight software for NASA's Apollo Moon missions.
"Looking back, we were the luckiest people in the world. There was no choice but to be pioneers; no time to be beginners."
10. Jocelyn Bell Burnell (Dame Susan Jocelyn Bell Burnell, 15 July 1943) is an astrophysicist from Northern Ireland who, as a postgraduate student, discovered the first radio pulsars in 1967. The discovery was recognised by the award of the 1974 Nobel Prize in Physics but, despite being the first person to discover the pulsars, she was not one of the recipients of the prize. The paper announcing the discovery of pulsars had five authors. Bell's thesis supervisor Antony Hewish was listed first, Bell second. Hewish was awarded the Nobel Prize, along with the astronomer Martin Ryle. Bell Burnell served as president of the Royal Astronomical Society from 2002 to 2004, as president of the Institute of Physics from October 2008 until October 2010, and as interim president of the Institute following the death of her successor, Marshall Stoneham, in early 2011.
"Arguably, my student status and perhaps my gender were also my downfall with respect to the Nobel Prize, which was awarded to Professor Antony Hewish and Professor Martin Ryle. At the time, science was still perceived as being carried out by distinguished men."
9000 year old Neolithic Spirit Masks, the World’s Oldest Masks.
These masks were unearthed in the Judean desert around Jerusalem and were sculpted by some of our earliest ancestors who decided to give up the hunter gatherer lifestyle to instead settle in the Judean hills, beginning a farming lifestyle.
It is thought that this change in existence sparked more organised religious beliefs and a worship of ancestors, prompting a necessity for artifacts such as these.
Numerous masks like these have been found in the region. Sometimes, they are found as a result of an archaeological excavation in areas with thousands of other objects. Things such as rope baskets, beads, shells, flint knives, bone figurines and decorated human skulls. Some of these stone masks even had hair attached as beards and moustaches.
In other cases though, these masks have been found by accident. One such case was an accidental discovery by a farmer who was tilling a field in the early 1970s. From there, they fell into the hands of an antique dealer. Sadly, after changing possession numerous times, the precise location of where the masks were found is unknown.
These mesmerizing kinetic sculptures built by Anthony Howe are entirely wind-driven. It's not necessarily apparent in these images, but these sculptures are several meters tall and weigh hundreds of kilograms, but they're engineered so precisely that the slightest breeze sets them silently spinning. (Video and image credits: A. Howe; via Colossal)
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Our Nancy Grace Roman Space Telescope team recently flight-certified all 24 of the detectors the mission needs. When Roman launches in the mid-2020s, the detectors will convert starlight into electrical signals, which will then be decoded into 300-megapixel images of huge patches of the sky. These images will help astronomers explore all kinds of things, from rogue planets and black holes to dark matter and dark energy.
Eighteen of the detectors will be used in Roman’s camera, while another six will be reserved as backups. Each detector has 16 million tiny pixels, so Roman’s images will be super sharp, like Hubble’s.
The image above shows one of Roman’s detectors compared to an entire cell phone camera, which looks tiny by comparison. The best modern cell phone cameras can provide around 12-megapixel images. Since Roman will have 18 detectors that have 16 million pixels each, the mission will capture 300-megapixel panoramas of space.
The combination of such crisp resolution and Roman’s huge view has never been possible on a space-based telescope before and will make the Nancy Grace Roman Space Telescope a powerful tool in the future.
Learn more about the Roman Space Telescope!
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It’s always interesting to pick up specialized, esoteric terminology from experienced scientists and engineers. The language you hear on the job is very different than what you learned in lecture halls!
For example, in school, you might learn how to calculate that 4.6 GHz radio waves have a wavelength of 6.51 centimeters. On the job, the RF engineer will tell you that once you get to wavelengths much below 10 cm, radio tends to “wiggle through” unexpected gaps and “leak everywhere,” where it becomes a “huge pain in the ass.”
In school, you might learn that many metals will reflect neutron radiation. On the job, the plasma physicist will tell you that neutrons tend to “rattle around” inside steel coaxial cables and use them as channels to fly out into the building, where they will “ruin your day” and “piss off the nuclear safety people” if you don’t shield them right.
In school, you might learn that tungsten is an extremely dense material that makes for very good thermal shielding in extreme environments, but it can be challenging to machine. On the job, the mechanical engineer will tell you that working with tungsten is “the fucking worst” and if they have to build “an entire god damn wall of shielding tiles” out of it, they will “seriously pitch a fit.”
The fascinating and unique vocabulary of scientists is always such a pleasure to learn!