What is the mass of the Central Black Hole of the Phoenix Cluster?
Here’s a nice animation to blow your mind.
20 BILLION of our SUNS.
Reid Wiseman Vines: That’s not the Sun, it’s the Moon setting on a gorgeous night.
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
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
First imaged in 1989, red sprites are a ghostly phenomenon that occur at high altitudes above thunderstorms. Photographed here by ESO Photo Ambassador Petr Horálek, the unmistakable tendrils of multiple red sprites are spotted approximately 600 kilometres away from ESO’s Paranal Observatory above distant thunderclouds.
To capture multiple sprites in one image, two exposures were combined. The upper sprite occurred nearly 21 minutes before the lower one.
In the foreground sits a lone 1.8-metre Auxiliary Telescope, part of ESO’s Very Large Telescope (VLT).
Credit: P. Horálek/ESO
Magnetic Wormhole Created in Lab
“Ripped from the pages of a sci-fi novel, physicists have crafted a wormhole that tunnels a magnetic field through space.
“This device can transmit the magnetic field from one point in space to another point, through a path that is magnetically invisible,” said study co-author Jordi Prat-Camps, a doctoral candidate in physics at the Autonomous University of Barcelona in Spain. “From a magnetic point of view, this device acts like a wormhole, as if the magnetic field was transferred through an extra special dimension.“
The idea of a wormhole comes from Albert Einstein’s theories. In 1935, Einstein and colleague Nathan Rosen realized that the general theory of relativity allowed for the existence of bridges that could link two different points in space-time. Theoretically these Einstein-Rosen bridges, or wormholes, could allow something to tunnel instantly between great distances (though the tunnels in this theory are extremely tiny, so ordinarily wouldn’t fit a space traveler). So far, no one has found evidence that space-time wormholes actually exist.
The new wormhole isn’t a space-time wormhole per se, but is instead a realization of a futuristic “invisibility cloak” first proposed in 2007 in the journal Physical Review Letters. This type of wormhole would hide electromagnetic waves from view from the outside. The trouble was, to make the method work for light required materials that are extremely impractical and difficult to work with, Prat said.
But it turned out the materials to make a magnetic wormhole already exist and are much simpler to come by. In particular, superconductors, which can carry high levels of current, or charged particles, expel magnetic field lines from their interiors, essentially bending or distorting these lines. This essentially allows the magnetic field to do something different from its surrounding 3D environment, which is the first step in concealing the disturbance in a magnetic field.So the team designed a three-layer object, consisting of two concentric spheres with an interior spiral-cylinder. The interior layer essentially transmitted a magnetic field from one end to the other, while the other two layers acted to conceal the field’s existence.”
Extreme physics BBQ!
This is what happens when you pump mains electricity through a steak (using a kettle as a resistor), when you focus the beams from a strong light source onto one piece of steak, and when you try to fry prawns using a bottle rocket.
As electricity is forced through the steak, electrons interact with the atoms and molecules of the meat. As the steak doesn’t conduct very well, the electrons have to push very hard, and in doing so transfer energy to the meat - a process known as joule heating.
Parabolas focus all the incoming energy into one spot. We harnessed that to cook a steak.
And we whipped out our old favourite - bottle rockets - to fry our prawns. Had to sort out a projectile prawn issue first, though.
Click here to watch the whole video on our YouTube channel. And check out the extreme chemistry approach over at Brit Lab.
* (You look inside...) * (Inside the joke book is a quantum physics book.)
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