Just imagine a world full of beautiful stained glass windows which also generate electricity…
[Oxford Photovoltaics]
Puritans, Goths, avant-garde artists, hell-raising poets and fashion icon Coco Chanel all saw something special in it. Now black, that most enigmatic of colours, has become even darker and more mysterious.
A British company has produced a “strange, alien” material so black that it absorbs all but 0.035 per cent of visual light, setting a new world record. To stare at the “super black” coating made of carbon nanotubes – each 10,000 times thinner than a human hair – is an odd experience. It is so dark that the human eye cannot understand what it is seeing. Shapes and contours are lost, leaving nothing but an apparent abyss.
Today, June 30 is International Asteroid Day. Here are some things to know about our fascinating space rubble.
Asteroids—named by British astronomer William Herschel from the Greek expression meaning “star-like"—are rocky, airless worlds that are too small to be called planets. But what they might lack in size they certainly make up for in number: An estimated 1.1 to 1.9 million asteroids larger than 1 kilometer are in the Main Belt between the orbits of Mars and Jupiter. And there are millions more that are smaller in size. Asteroids range in size from Vesta—the largest at about 329 miles (529 kilometers) wide—to bodies that are just a few feet across.
Asteroids are generally categorized into three types: carbon-rich, silicate, or metallic, or some combination of the three. Why the different types? It all comes down to how far from the sun they formed. Some experienced high temperatures and partly melted, with iron sinking to the center and volcanic lava forced to the surface. The asteroid Vesta is one example we know of today.
If all of the asteroids were combined into a ball, they would still be much smaller than the Earth’s moon.
In 1801, Giuseppe Piazzi discovered the first and then-largest asteroid, Ceres, orbiting between Mars and Jupiter. Ceres is so large that it encompasses about one-fourth of the estimated total mass of all the asteroids in the asteroid belt. In 2006, its classification changed from asteroid to as a dwarf planet.
NASA’s Psyche mission will launch in 2022 to explore an all-metal asteroid—what could be the core of an early planet—for the very first time. And in October 2021, the Lucy mission will be the first to visit Jupiter’s swarms of Trojan asteroids.
The term ‘near’ in near-Earth asteroid is actually a misnomer; most of these bodies do not come close to Earth at all. By definition, a near-Earth asteroid is an asteroid that comes within 28 million miles (44 million km) of Earth’s orbit. As of June 19, 2017, there are 16,209 known near-Earth asteroids, with 1,803 classified as potentially hazardous asteroids (those that could someday pose a threat to Earth).
About once a year, a car-sized asteroid hits Earth’s atmosphere, creates an impressive fireball, and burns up before reaching the surface.
Ground-based observatories and facilities such as Pan-STARRS, the Catalina Sky Survey, and ATLAS are constantly on the hunt to detect near-Earth asteroids. NASA also has a small infrared observatory in orbit about the Earth: NEOWISE. In addition to detecting asteroids and comets, NEOWISE also characterizes these small bodies.
Roughly one-sixth of the asteroid population have a small companion moon (some even have two moons). The first discovery of an asteroid-moon system was of asteroid Ida and its moon Dactyl in 1993.
Several NASA space missions have flown to and observed asteroids. The NEAR Shoemaker mission landed on asteroid Eros in 2001 and NASA’s Dawn mission was the first mission to orbit an asteroid in 2011. In 2005, the Japanese spacecraft Hayabusa landed on asteroid Itokawa. Currently, NASA’s OSIRIS-REx is en route to a near-Earth asteroid called Bennu; it will bring a small sample back to Earth for study.
Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com
Tesla reveals solar roof tiles
Electric carmaker Tesla has unveiled a new design of solar roof panels with integrated photovoltaic cells that are not visible from the outside. The tiles, made from glass, are intended to be a more attractive way to add solar panels to homes, by disguising the cells through a coloured film.
Presenting the new tiles for the first time, Elon Musk, Chief Executive of Tesla, said, ‘We need to make solar panels as appealing as electric cars have become. The goal is to have solar roofs that look better than a normal roof.’
Musk demonstrated in the launch the strength of his new roofing product, testing heavy weights on three common roofing shingles as well as his own. The Tesla roof was the only one that could withstand the weight and pressure. ‘It’s made of quartz. It has a quasi-infinite lifetime,’ explained Musk.
The new roof will be offered in four designs including Tuscan glass, slate glass, textured glass and smooth glass tile. Elon Musk presented the Solar Roof during a Tesla event at Universal Studios, USA.
In other news:
· New surfaces repel water in oil as well as oil in water
· Rewritable material could help reduce paper waste
· Ministers reject calls for 5p charge on UK’s disposable coffee cups
· Electric current used to track water in concrete
To find out more on materials science, packaging and engineering news, visit our website IOM3 or follow us on Twitter @MaterialsWorld for regular news updates. You can also now get access to our content any time, offline and online, anywhere via our app. For more information, visit app.materialsworld.org
You might be an engineer if you know how long a zeptosecond is. (It's a trillionth of a billionth of a second!) http://ow.ly/uUUb30caXrH
Dude, bullets are literally made to shatter on impact. It's to prevent over-penetration. Bullets frequently shatter if they hit human bone inside a body, for example. So congrats, a katana is as good at stopping bullets as a human bone. Or a regular butter knife. Or even a regular piece of old steel. Like the ones used in a target range. Ever wonder why the steel plates at target ranges don't have holes in them even tho rifle caliber bullets hit them? It's cause the bullet shatters on impact.
To be very clear, the intention of the post was never to say that Katana is the ultimate sword. It was merely to enlighten the possibility of the bullet getting shattered by a sword/Knife.
Yes, bullets do shatter on impact.
But I am not so sure about what you say about the human bone though.
I believe it really depends on that kinetic energy of the bullet, the bullet size and the place of impact of the bullet on the body.
And even with the tissues surrounding the bone, there have been many instances where the Femur ( thigh bone ) fractured on impact.
If anyone reading this has a background in the field, would highly appreciate to hear your stance on this.
Thanks for asking anon ! :D
“The biggest challenge facing a real-life cloak has been the incorporation of a large variety of wavelengths, as the cloak’s material must vary from point-to-point to bend (and then unbend) the light by the proper amount. Based on the materials discovered so far, we haven’t yet managed to penetrate the visible light portion of the spectrum with a cloak. This new advance in metalenses, however, seems to indicate that if you can do it for a single, narrow wavelength, you can apply this nanofin technology to extend the wavelength covered tremendously. This first application to achromatic lenses covered nearly the full visible-light spectrum (from 470 to 670 nm), and fusing this with advances in metamaterials would make visible-light cloaking devices a reality.”
What would it take to have a true cloaking device? You’d need some way to bend the light coming from all across the electromagnetic spectrum around your cloaked object, and have it propagate off in the same direction once it moved past you. To an outside observer, it would simply seem like the cloaked object wasn’t there, and they’d only view the world in front of and behind them. Even with the recent advances that have been made in metamaterials, we have not yet been able to realize this dream in three dimensions, covering the entire electromagnetic spectrum, and from all directions. But a new advance in metalens technology might get you the full electromagnetic spectrum after all, as they appear to have solved the problem of chromatic aberration with a light, small, and inexpensive solution. If we can combine these two technologies, metalenses and metamaterials, we just might realize the dream of a true invisibility cloak.
Whether you’re a Star Trek or Harry Potter fan, the ability to turn yourself invisible would be Earth-shattering. Come see how transformation optics might transform the world!
2016 has been a great year for FYP!
And we would like to conclude it with some of the best posts that we have been able to produce
Part - I , II, III
Thank you so much following us ! Have a great weekend :D
- Fuck Yeah Physics!
Google’s Wireless ‘Pixel Buds’ Headphones Can Translate 40 Languages in Real Time
These giant mesh nets provide drinking water in the driest desert on Earth.