Nanoparticles are particles between 1 and 100 nanometers in size. In nanotechnology, a particle is defined as a small object that behaves as a whole unit with respect to its transport and properties.Particles are further classified according to diameter.[1] Ultrafine particles are the same as nanoparticles and between 1 and 100 nanometers in size, fine particles are sized between 100 and 2,500 nanometers, and coarse particles cover a range between 2,500 and 10,000 nanometers. Nanoparticle research is currently an area of intense scientific interest due to a wide variety of potential applications in biomedical, optical and electronic fields.[2][3][4][5] TheNational Nanotechnology Initiative has led to generous public funding for nanoparticle research in the United States.
[Source]
Phroyd
Ever see an antacid dissolve in water…in space? Read more via io9.
Youngster Galaxy Magnified by Abell 383
Hubble was first to spot this galaxy, one of the youngest in the distant universe. Its stars formed 13.5 billion years ago, a mere 200 million years after the Big Bang. The galaxy’s image is magnified by the gravity of a massive cluster of galaxies (Abell 383) parked in front of it, making it appear eleven times brighter. This phenomenon is called gravitational lensing.
Image Credit: NASA, ESA, J. Richard (Centre for Astronomical Research/Observatory of Lyon, France), and J.-P Kneib (Astrophysical Laboratory of Marseille, France).
Reid Wiseman Vines: That’s not the Sun, it’s the Moon setting on a gorgeous night.
Stephen Hawking challenges the notion of black holes as we know them in a new paper (still awaiting peer-review)
“’There is no escape from a black hole in classical theory,’ Hawking told Nature. Quantum theory, however, ‘enables energy and information to escape from a black hole’. A full explanation of the process, the physicist admits, would require a theory that successfully merges gravity with the other fundamental forces of nature. But that is a goal that has eluded physicists for nearly a century. 'The correct treatment,’ Hawking says, 'remains a mystery.’Hawking’s new work is an attempt to solve what is known as the black-hole firewall paradox, which has been vexing physicists for almost two years, after it was discovered by theoretical physicist Joseph Polchinski of the Kavli Institute and his colleagues…. (read more)”
The finding suggests that quasars—the brilliant cores of active galaxies – may commonly host two central supermassive black holes, which fall into orbit about one another as a result of the merger between two galaxies. Like a pair of whirling skaters, the black-hole duo generates tremendous amounts of energy that makes the core of the host galaxy outshine the glow of its population of billions of stars, which scientists then identify as quasars.
Scientists looked at Hubble archival observations of ultraviolet radiation emitted from the center of Mrk 231 to discover what they describe as “extreme and surprising properties.”
If only one black hole were present in the center of the quasar, the whole accretion disk made of surrounding hot gas would glow in ultraviolet rays. Instead, the ultraviolet glow of the dusty disk abruptly drops off toward the center. This provides observational evidence that the disk has a big donut hole encircling the central black hole. The best explanation for the donut hole in the disk, based on dynamical models, is that the center of the disk is carved out by the action of two black holes orbiting each other. The second, smaller black hole orbits in the inner edge of the accretion disk, and has its own mini-disk with an ultraviolet glow.
Read more ~ NASA.gov
Image: This artistic illustration is of a binary black hole found in the center of the nearest quasar to Earth, Markarian 231. Credits: NASA, ESA, and G. Bacon (STScI)
NASA | Thermonuclear Art – The Sun In Ultra-HD
Watch the whole video here.
(CNN)
On Wednesday, Oct. 28 and Friday, Nov. 6, Commander Scott Kelly and Flight Engineer Kjell Lindgren will perform spacewalks in support of space station assembly and maintenance. You can watch both of these events live on NASA Television. But, before you do, here are 7 things to know:
1. What’s the Point of a Spacewalk?
Spacewalks are important events where crew members repair, maintain and upgrade parts of the International Space Station. Spacewalks can also be referred to as an EVA – Extravehicular Activity. On Wednesday, Oct. 28, Commander Scott Kelly and Flight Engineer Kjell Lindgren will complete a spacewalk. During this time they will service the Canadarm2 robotic arm, route cables for a future docking port, and place a thermal cover over a dark matter detection experiment, which is a state-of-the-art particles physics detector that has been attached to the station since 2011.
2. What Do They Wear?
The Extravehicular Mobility Unit (EMU) spacewalking suit weighs around 350 pounds. It’s weightless in space, but mass is still very real. The EMU provides a crew member with life support and an enclosure that enables them to work outside the space station. The suit provides atmospheric containment, thermal insulation, cooling, solar radiation protection and micrometeoroid/orbital debris protection.
3. How Long Are Spacewalks?
Spacewalks typically last around 6 ½ hours, but can be extended to 7 or 8 hours, if necessary. The timeline is designed to accommodate as many tasks as possible, as spacewalks require an enormous amount of work to prepare.
4. What About Eating and Drinking?
Before a spacewalk astronauts eat light, usually something like a protein bar. The spacesuits also have a drink bag inside, and there is a bite valve that allows ready access to water.
5. What About Communication?
Spacewalkers wear a ‘comm’ cap that allows them to constantly communicate with astronauts inside the space station that are helping with the walk, and with mission control. Astronauts also wear a checklist on their left wrist called a “cuff checklist”. This list contains emergency procedures.
6. What About Light?
Something that most people don’t realize about spacewalks is that the crew will experience a sunrise/sunset every 45 minutes. Luckily, their spacesuits are equipped with lights that allow them to see in times of darkness.
7. How Do They Stay Safe?
When on a spacewalk, astronauts use safety tethers to stay close to their spacecraft. One end of the tether is hooked to the spacewalker, while the other end is connected to the vehicle. Another way astronauts stay safe is by wearing a SAFER, which is a Simplified Aid for EVA Rescue. This device is worn like a backpack and uses small jet thrusters to let an astronaut move around in space.
You can watch both of the upcoming spacewalks live on: NASA Television or the NASA App, or follow along on @Space_Station Twitter.
Wednesday, Oct. 28: Coverage begins at 6:30 a.m. EDT. Spacewalk begins at 8:10 a.m.
Friday, Nov. 6: Coverage begins at 5:45 a.m. EDT. Spacewalk begins at 7:15 a.m.
Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com
It’s a bad day both for Albert Einstein and for hackers. The most rigorous test of quantum theory ever carried out has confirmed that the ‘spooky action at a distance’ that the German physicist famously hated — in which manipulating one object instantaneously seems to affect another, far away one — is an inherent part of the quantum world.
The experiment, performed in the Netherlands, could be the final nail in the coffin for models of the atomic world that are more intuitive than standard quantum mechanics, say some physicists. It could also enable quantum engineers to develop a new suite of ultrasecure cryptographic devices.
“From a fundamental point of view, this is truly history-making,” says Nicolas Gisin, a quantum physicist at the University of Geneva in Switzerland.
Continue Reading.
* (You look inside...) * (Inside the joke book is a quantum physics book.)
44 posts