JAD Extra

La vacuna sin agujas... ¡Por fin! — Amazings.es

Mon, 20 Aug 2012 16:45:33 -0400

La vacuna sin agujas... ¡Por fin! — Amazings.es

expose-the-light: 10 Things You Didn’t Know About Black...

Sun, 22 Jul 2012 16:04:48 -0400

10 Things You Didn’t Know About Black Holes

Stars whose size is 10 or 15 times as massive as the Sun, generally have a fate of becoming black holes. Small stars, however, die as white dwarfs or neutron stars. So how do large stars become black holes? As stars begin to grow old, they gradually expand and they slowly run out of their supply of hydrogen and then helium. This causes contraction of their cores and expansion of the outer layers. The stars start becoming cooler and less bright and they come to a stage which is known as the red giant phase. Now, for a star which is even 3 times or more the mass of the Sun, undergoes detonation (a violent release of energy caused by a chemical or nuclear reaction) in cataclysms known as supernovae. Such kind of explosion results in scattering of most of a star into the space. However, it also leaves behind a cold remnant of the star, which is no longer able to execute any nuclear fusion reaction.

As there is no fusion in the dead remnants of a massive supernova star, there is no creation of any energy which can oppose the inward pull of gravity caused by the star’s own mass. Thus, the star enters a phase where it begins to collapse in upon itself. This is the formation of the black hole, wherein, it starts shrinking to zero volume. So, with volume being zero, density becomes infinite, so much that even light becomes unable to escape its massively strong gravitational pull. As a result of this, even the light of the dead remnants of the star gets trapped in its orbit and this dark star evolves to become what is known as a black hole.

It has been estimated that there might be black holes of enormous size, which may be existing at the center of our galaxy, ‘The Milky Way’. These holes are assumed to be having the mass of 10 - 100 billion suns. Now, that is something which is ‘HUGE’, in block letters!

Cygnus X-1 is the black hole that is located about 8000 light years away from our planet Earth. This is the closest black hole to Earth, known to man.

Although, black holes are associated with the reputation of having the strongest suction force, they do not bear the capability to absorb the whole universe. Anything such as planets, light and other matter, can be pulled into the grasp of black holes, only if they happen to cross what is known as the event horizon. The radius of this event horizon is known as the Schwarzschild radius and at this radius, the escape velocity equals the speed of the light. So, once an object has passed through it, it must travel faster than light in order to escape it. That is the reason why, even light cannot escape the event horizon of a black hole.

As mentioned earlier, in this part of black holes in space, only the largest of stars are capable to end up as black holes. Only these stars are massive enough to get compressed to the Schwarzschild radius. While, smaller stars end up as white dwarfs or neutron stars.

There are several black holes which exist in binary star systems. Stars which are neighboring such holes, will keep on shrinking as their mass will continually be pulled by these holes. Gradually, the black holes will go on increasing, until the other stars have vanished.

As light cannot escape from a black hole, it cannot be directly observed. However, scientists use the presence of matters which swirl around the hole. Such matters are usually gas and dust and they heat up and emit radiation which can be detected.

Talking about our Sun becoming a black hole, the phenomenon won’t occur. This is because the sun is not massive enough to shrink into a black hole. However, it will end up to become a white dwarf, after several billion years.

The center of a black hole is void of time and space.

A giant elliptical galaxy in the constellation Virgo, is assumed to home the largest known black hole. This hole is about 3 billion times the mass of the Sun.

Larger black holes are known to suck up other smaller ones which are close to their vicinity.

No matter, how many facts people come up with, black holes represent an endless journey in the vast darkness of the space. The concept which lay hidden in the lap of black holes, perhaps, is the most appropriate analogy to the saying ‘sky is the limit!’

In the image: Simulation of gas cloud approaching the black hole at the center of the Milky Way

BBC Mundo - ¿Un Mundo Feliz? - Videojuegos como televisión

Wed, 09 May 2012 09:10:08 -0400

BBC Mundo - ¿Un Mundo Feliz? - Videojuegos como televisión

Las abejas pueden inspirar el desarrollo de programas informáticos

Fri, 04 May 2012 06:24:22 -0400

Las abejas pueden inspirar el desarrollo de programas informáticos

8bitfuture: New flexible solar cells are thinner than spider...

Thu, 26 Apr 2012 03:14:50 -0400

8bitfuture:

New flexible solar cells are thinner than spider silk.

Austrian scientists have developed flexible, stretchable solar cells on thin plastic foil substrates, able to generate a record 10 watts per gram. The cells have a 4.2% power conversion efficiency, which puts it ahead of this flexible solar system I covered earlier this week. Typical solar panels have around 12-17% efficiency.

The above image shows the cells being wrapped around a human hair only 70 microns wide. The cells are based on a commercially available substrate of PET film, with the total device measuring 1.9 microns thick - around a quarter of the thickness of traditional solar cells.

Trazan el árbol de la vida hasta una forma ancestral única

Wed, 25 Apr 2012 09:34:53 -0400

Trazan el árbol de la vida hasta una forma ancestral única

BBC Mundo - Noticias - Lo que aqueja a la economía española

Fri, 20 Apr 2012 06:21:13 -0400

BBC Mundo - Noticias - Lo que aqueja a la economía española

Cómo conseguir que Internet vaya más rápido

Fri, 13 Apr 2012 09:22:34 -0400

Cómo conseguir que Internet vaya más rápido

A subasta un prototipo de Macintosh que nunca salió al mercado | Navegante | elmundo.es

Thu, 12 Apr 2012 07:45:02 -0400

A subasta un prototipo de Macintosh que nunca salió al mercado | Navegante | elmundo.es

Ciencia Kanija » Herschel observa una masacre cometaria alrededor de una estrella cercana

Thu, 12 Apr 2012 07:31:30 -0400

Ciencia Kanija » Herschel observa una masacre cometaria alrededor de una estrella cercana

ESA Multimedia Gallery - Images - Hubble Space Telescope (HST)

Wed, 11 Apr 2012 06:29:30 -0400

ESA Multimedia Gallery - Images - Hubble Space Telescope (HST)

8bitfuture: Prototype motor could reach the Moon using only a...

Mon, 02 Apr 2012 09:19:39 -0400

8bitfuture:

Prototype motor could reach the Moon using only a tenth of a litre of fuel.

The MicroThrust motor is the result of a joint European venture to enable low cost space exploration. The thruster weighs only a few hundred grams, and is designed to propel small satellites of up to 100kg.

”At the moment, nanosatellites are stuck in their orbits. Our goal is to set them free,” explains the project director.

Small satellites are all the rage right now because their manufacturing and launch costs are relatively low – about half a million dollars, compared to conventional satellites that run into the hundreds of millions. But nanosatellites currently lack an efficient propulsion system that would render them truly autonomous and thus able to carry out exploration or observation missions.

The system uses “ionic liquid”, as opposed to a combustible fuel. The liquid contains electrically charged molecules, which are extracted from it and expelled via an electric field to generate thrust.

After six months of acceleration, the microsatellite’s speed increases from 24,000 km/h, its launch speed, to 42,000 km/h. The acceleration is only about a tenth of a millimeter per square second, which translates into 0-100 km/h in 77 hours. But in space, where there is no friction to impede motion, gentle but steady acceleration is the way to go.

The technology is planned to be used to power CleanSpace One.

8bitfuture: Space X plans passenger trips to Mars in 10 - 15...

Fri, 23 Mar 2012 17:33:35 -0400

8bitfuture:

Space X plans passenger trips to Mars in 10 - 15 years.

SpaceX founder Elon Musk has revealed in an interview his plans to offer return passenger flights to Mars. While admitting initial trips would be unaffordable for most people, he says after 10 years of operation the cost should drop to around $500,000.

He says the key to the system will be to make everything reusable, as well as having the ability to refuel on Mars.

“My vision is for a fully reusable rocket transport system between Earth and Mars that is able to re-fuel on Mars - this is very important - so you don’t have to carry the return fuel when you go there,” he said.

“The whole system [must be] reusable - nothing is thrown away. That’s very important because then you’re just down to the cost of the propellant.

“We will probably unveil the overall strategy later this year in a little more detail, but I’m quite confident that it could work and that ultimately we could offer a round trip to Mars that the average person could afford - let’s say the average person after they’ve made some savings.”

El ministre de Defensa, vinculat a la fabricació de míssils i de bombes de fragmentació - VilaWeb

Mon, 19 Mar 2012 17:08:51 -0400

El ministre de Defensa, vinculat a la fabricació de míssils i de bombes de fragmentació - VilaWeb

Más fácil, más corto y más barato | Economía | EL PAÍS - Link - Hashonomy

Sun, 18 Mar 2012 09:44:34 -0400

Más fácil, más corto y más barato | Economía | EL PAÍS - Link - Hashonomy

La Red ya sabe c?o sortear la lucha contra las descargas | Navegante | elmundo.es - Link - Hashonomy

Sun, 18 Mar 2012 09:43:22 -0400

La Red ya sabe c?o sortear la lucha contra las descargas | Navegante | elmundo.es - Link - Hashonomy

15 Websites to Download Free Stock Photos | Flash User

Sun, 18 Mar 2012 09:31:59 -0400

15 Websites to Download Free Stock Photos | Flash User

8bitfuture: Infographic: A day in the internet. Some...

Fri, 16 Mar 2012 07:21:22 -0400

8bitfuture:

Infographic: A day in the internet.

Some interesting stats:

172 million different people visit Facebook, compared to 20 million for Google+ and 17 million for Pinterest. That’s a pretty good result for Pinterest compared to G+, I had no idea it was so big. And I still don’t get it.

4.7 billion minutes are spent on Facebook every day.

98 years worth of video is uploaded to YouTube every day. (Unbelievable!)

Check out the full infographic here at MBA online.

8bitfuture: New research shows our Moon could one day have...

Fri, 16 Mar 2012 07:17:22 -0400

8bitfuture:

New research shows our Moon could one day have volcanoes.

It’s long been known that the Moon has had a volcanic past, which is thought to have ended around three billion years ago. Now new research suggests that there is still molten magma deep inside the Moon, which could one day erupt again.

New experiments show that the magma is currently too dense to rise to the surface. To come to that conclusion, a team at the University of Amsterdam produced copies of the moon rock samples brought back by the Apollo missions, and melted them at the exact temperatures and pressures found inside the Moon. The densities were then measured using X-ray beams.

The team has suggested that although the magma is currently too dense to rise to the surface and form an active volcano, over time it will cool and become less dense that its surroundings. That lighter magma could one day form an active volcano, although the team is quick to point out it’s just a hypothesis and will need further testing.

8bitfuture: Robots are taking over my job. Artificial...

Fri, 16 Mar 2012 07:16:50 -0400

8bitfuture:

Robots are taking over my job.

Artificial intelligence researchers in Spain say they have developed an automatic air navigation and collision avoidance model using an automatic learning system.

The software solution, researchers claimed, aligns aircraft flight paths with other nearby aircrafts in a dense airspace such as an airport. If the aircraft is heading towards a building, it automatically avoids the obstacle. And, if several aircrafts are about to land on the same runway, the system prioritizes landing maneuvers without human intervention, they noted.

The model (so far only run as a computer simulation) controls all aircraft manoeuvres from start to finish, with no intervention from the pilots. It also keeps aircraft clear of poor weather or restricted airspace.

As someone who works as an air traffic controller, this system seems a bit crazy to me - for starters, what are the planes doing near buildings to start with! While systems like these have a long way to go to replace human pilots and controllers (phew) it could still be useful as an extra safety measure against collisions, like the already used TCAS system.