jtotheizzoe: Space Sounds - Sounds of the Big Bang It's time...
Space Sounds - Sounds of the Big Bang
It's time for another Episode Extra! (which is where you special blog readers get to check out really cool stuff to go along with my YouTube videos, like special features on a DVD, only way more special-er)
I've got another extra feature to go along with my latest Space Sounds video! I'm full of 'em this week.
The very first radiation to escape after the Big Bang has been traveling outward for 13.8 billion years. This cosmic microwave background has been literally stretched over time, it's frequency and temperature lowering as the universe, and everything in it, expands.
John G. Cramer from the University of Washington took the measurement data of the cosmic microwave background from ESA's Planck space telescope and converted the energy frequencies of the first 760,000 years of the universe into audible sound. He had to multiply each frequency by 10^26 so we could hear it!
More "space sounds" episode extras here. Click here to subscribe on YouTube!
Magical Forest "One day before new moon I took this picture in...
Magical Forest
"One day before new moon I took this picture in a calm and starry night. A passing car illuminated the forest but did not spoil the reflections on the lake surface." — Helmut R. Kahr
Mind Over Mechanics In a jaw-dropping feat of engineering,...
In a jaw-dropping feat of engineering, electronics turn a person's thoughts into commands for a robot. Using a brain-computer interface technology pioneered by University of Minnesota biomedical engineering professor Bin He, several young people have learned to use their thoughts to steer a flying robot around a gym, making it turn, rise, dip, and even sail through a ring.
The technology may someday allow people robbed of speech and mobility by neurodegenerative diseases to regain function by controlling artificial limbs, wheelchairs, or other devices. And it's completely noninvasive: Brain waves (EEG) are picked up by the electrodes of an EEG cap on the scalp, not a chip implanted in the brain.
A report on the technology has been published in the Journal of Neural Engineering: http://iopscience.iop.org/1741-2552/1…
Full story: http://z.umn.edu/e78
Chandra, Spitzer Study Suggests Black Holes Abundant Among the...
Chandra, Spitzer Study Suggests Black Holes Abundant Among the Earliest Stars
By comparing infrared and X-ray background signals across the same stretch of sky, an international team of astronomers has discovered evidence of a significant number of black holes that accompanied the first stars in the universe.
Using data from NASA's Chandra X-ray Observatory and NASA's Spitzer Space Telescope, which observes in the infrared, researchers have concluded one of every five sources contributing to the infrared signalis a black hole.
"Nobody ever figures out what life is all about, and it doesn't matter. Explore the world. Nearly..."
"Nobody ever figures out what life is all about, and it doesn't matter. Explore the world. Nearly everything is really interesting if you go into it deeply enough."- Richard P. Feynman (via larmoyante)
ikenbot: The Cosmos as Seen From Namibia, Africa 1. Center of...
The Cosmos as Seen From Namibia, Africa
1. Center of Milky Way wideangle view 2. Omega Nebula 3. Trifid and Lagoon nebulas 4. south celestial pole view with Crux and Magellanic Clouds — Martin Reitze
Kepler Stars and Planets are Bigger Than Previously...
Kepler Stars and Planets are Bigger Than Previously Thought
(Phys.org) —In a new study using the NOAO Kitt Peak National Observatory Mayall 4-meter telescope, observations of a large sample of stars with candidate planets identified by the NASA Kepler Mission have revealed that many of the stars, and hence their planets, are actually somewhat larger than originally thought. In addition, the researchers confirm that planets larger than Neptune are more likely to be found orbiting stars that contain more heavy elements (such as iron) than the Sun. Small planets, however, have been discovered around stars both rich and poor in metals.
Over three years ago, Steve B. Howell (NASA Ames Research Center) put together a team to investigate and characterize the stars that the NASA Kepler Mission found to host planets. The team members are Mark Everett and David Silva (both at NOAO) and Paula Szkody (University of Washington).
What is a Black Hole? Don't let the name fool you: a...
What is a Black Hole?
Don't let the name fool you: a black hole is anything but empty space. Rather, it is a great amount of matter packed into a very small area - think of a star ten times more massive than the Sun squeezed into a sphere approximately the diameter of New York City. The result is a gravitational field so strong that nothing, not even light, can escape. In recent years, NASA instruments have painted a new picture of these strange objects that are, to many, the most fascinating objects in space.
Although the term was not coined until 1967 by Princeton physicist John Wheeler, the idea of an object in space so massive and dense that light could not escape it has been around for centuries. Most famously, black holes were predicted by Einstein's theory of general relativity, which showed that when a massive star dies, it leaves behind a small, dense remnant core. If the core's mass is more than about three times the mass of the Sun, the equations showed, the force of gravity overwhelms all other forces and produces a black hole.1
When black holes are discussed, one will often hear the terms event horizon and singularity. What are they?
Event Horizon
The event horizon of a black hole is the boundary ('horizon') between its 'outside' and its 'inside'; those outside cannot know anything about things ('events') which happen inside.2
Because of the event horizon, a virtual particle pair can be separated; one of the virtual particles can be pulled into a black hole while the other escapes outside of the event horizon. Upon losing mass, the black hole emits radiation. This is known as Hawking Radiation. More on that in a bit.
Singularity
Actually at the center of a black hole spacetime has infinite curvature and matter is crushed to infinite density under the pull of infinite gravity. At a singularity, space and time cease to exist as we know them. The laws of physics as we know them break down at a singularity, so it's not really possible to envision something with infinite density and zero volume.3
This notion of infinity is what Michio Kaku called the flaw in Einstein's theory of general relativity.4
So what is Hawking Radiation?
Cosmologist, astrophysicist, and physicist Stephen Hawking showed, in 1974, that black holes should emit electromagnetic radiation with a black body spectrum; this process is also called black hole evaporation. In brief, this theoretical process works like this: particle-antiparticle pairs are constantly being produced and rapidly disappear (through annihilation); these pairs are virtual pairs, and their existence (if something virtual can be said to exist!) is a certain consequence of the Uncertainty Principle. Normally, we don't ever see either the particle or antiparticle of these pairs, and only know of their existence through effects like the Casimir effect. However, if one such virtual pair pops into existence near the event horizon of a black hole, one may cross it while the other escapes; and the black hole thus loses mass. A long way away from the event horizon, this looks just like black body radiation.5
Black holes are exotic objects. Their properties may be just as, if not more, exotic.
In December of last year, researchers from the Neils Bohr Institute showed that black holes have properties of solids and liquids. One of the researchers, Jay Armas explained that "[t]he black branes are hydro-dynamic objects, that is to say that they have the properties of a liquid. We have now discovered that black branes also have properties, which can be explained in terms of solids. They can behave like elastic material when we bend them." He went on to explain "that when the black branes are bent and folded into a blackfold, a so-called piezoelectric effect (electricity that occurs due to pressure) is created. This new effect can be understood as a slightly bent and charged black string with a greater concentration of electric charge on the innermost side in relation to the outermost side. This produces two electrically charged poles on the black strings." Black branes and blackfolds are related to string theory.6
So are we any closer to photographing black holes? Indeed we are. An array of 50 radio telescopes from around the world will work together to photograph the supermassive black hole at the center of our galaxy, Sagittarius A* (Sgr A*).7 Supermassive black holes are thought to be the engines of galaxies.
On the other end of the size spectrum are the giants known as "supermassive" black holes, which are millions, if not billions, of times as massive as the Sun. Astronomers believe that supermassive black holes lie at the center of virtually all large galaxies, even our own Milky Way. Astronomers can detect them by watching for their effects on nearby stars and gas.*
However, they also come in smaller sizes-stellar sizes to be exact.
Although the basic formation process is understood, one perennial mystery in the science of black holes is that they appear to exist on two radically different size scales. On the one end, there are the countless black holes that are the remnants of massive stars. Peppered throughout the Universe, these "stellar mass" black holes are generally 10 to 24 times as massive as the Sun. Astronomers spot them when another star draws near enough for some of the matter surrounding it to be snared by the black hole's gravity, churning out x-rays in the process. Most stellar black holes, however, lead isolated lives and are impossible to detect. Judging from the number of stars large enough to produce such black holes, however, scientists estimate that there are as many as ten million to a billion such black holes in the Milky Way alone.*
*The source for these sections can be found in citation 1.
1 http://science.nasa.gov/astrophysics/focus-areas/black-holes/
2 http://www.universetoday.com/42471/event-horizon/
3 http://imagine.gsfc.nasa.gov/docs/ask_astro/answers/010912a.html
5 http://www.universetoday.com/40856/hawking-radiation/
6 http://www.sciencedaily.com/releases/2012/12/121211112959.htm
7 http://io9.com/5876842/scientists-prepare-to-capture-the-first+ever-picture-of-a-black-hole
GIF Courtesy: Watch Here
Astronomers Discover Light Echo From Supernova (Phys.org)...
Astronomers Discover Light Echo From Supernova
(Phys.org) —Astronomers have discovered light echoing off material surrounding a recent supernova explosion, SN 2009ig. The dust and gas that are reflecting the light are so close to the eruption center that it is likely related to the progenitor star. This discovery supports the theory that exploding white dwarfs become unstable from matter donated by large, non-degenerate stars.
The light echo seen from SN 2009ig is only the sixth discovered from a Type Ia supernova, and it is the most luminous of the echoes.
This Day in Science History Happy Birthday John Couch...
This Day in Science History
Happy Birthday John Couch Adams!
John Couch Adams was born in Cornwall, England in 1819 to a farming family. From a very early age he amazed everyone with his extraordinary abilities to do mathematical calculations in his head without the use of pen and paper. He was educated in mathematics at St. Johns College, Cambridge. While still an undergraduate, he performed an investigation to try to explain the reason for the irregularities in the motion of the planet Uranus. Adams theorized that the unexpected planetary orbit could be due to the presence of an as yet undiscovered planet in the vicinity. Adams theorized that the new planet was twice as far from the Sun as Uranus. All of the calculations were worked out in his head before he ever wrote them down. Once Adams did put his work on paper, he submitted it to the director of the Cambridge Observatory. The observatory took no action on his work. Several months later, Urbain Le Verrier submitted similar work to Johann Gottfried Galle, the director of the Berlin Observatory. Galle acted on Le Verrier's work and became the first person to observe Neptune. After the discovery of Neptune, the director of the Cambridge Observatory pointed out that John Couch Adams had been the first to predict the presence of Neptune. Le Verrier resented the effort to have Adams declared the sole discoverer of Neptune. Adams, a quiet, unambitious man was content to share the credit.
John Couch Adams made many other contributions to our knowledge of astronomy. For example, he studied the Leonid meteor shower and correctly concluded that the shower was the result of a comet passing close to Earth once a year. Adams was a mathematics professor at Cambridge and eventually became director of the Cambridge Observatory. He refused a knighthood offered by Queen Victoria to honor him for his accomplishments. Adams did not want the extra attention nor did he feel he had the money to maintain the lifestyle of a knight. He died in 1892 in Cambridge. Adams and his wife are buried under a 70 foot high granite cross in Cambridge. Three years after his death, he was honored with a memorial tablet in Westminster Abbey. The tablet is near the tablet that honors Sir Isaac Newton, another brilliant English mathematician.1
1 http://starchild.gsfc.nasa.gov/docs/StarChild/whos_who_level2/adams.html
Image Credit: University of Cambridge
Black Hole Cores May Not Be Infinitely Dense They may also serve...
Black Hole Cores May Not Be Infinitely Dense
They may also serve as bridges to the future.
The cores of black holes may not hold points of infinite density as currently thought, but portals to elsewhere in the universe, theoretical physicists say.
neuromorphogenesis: Manipulating Memory in the Hippocampus In...
Manipulating Memory in the Hippocampus
In the brain, cell-to-cell communication is dependent on neurotransmitters, chemicals that aid the transfer of information between neurons. Several proteins have the ability to modify the production of these chemicals by either increasing or decreasing their amount, or promoting or preventing their secretion. One example is tomosyn, which hinders the secretion of neurotransmitters in abnormal amounts.
Dr. Boaz Barak of Tel Aviv University's Sagol School of Neuroscience, in collaboration with Prof. Uri Ashery, used a method for modifying the levels of this protein in the mouse hippocampus — the region of the brain associated with learning and memory. It had a significant impact on the brain's activity: Over-production of the protein led to a sharp decline in the ability to learn and memorize information, the researchers reported in the journal NeuroMolecular Medicine.
"This study demonstrates that it is possible to manipulate various processes and neural circuits in the brain," says Dr. Barak, a finding which may aid in the development of therapeutic procedures for epilepsy and neurodegenerative diseases such as Alzheimer's. Slowing the transmission rate of information when the brain is overactive during epileptic seizures could have a beneficial effect, and readjusting the levels of tomosyn in an Alzheimer's patient may help increase cognition and combat memory loss.
A maze of memory loss
The researchers teamed up with a laboratory at the National Institutes of Health (NIH) in Baltimore to create a virus which produces the tomosyn protein. In the lab, the virus was injected into the hippocampus region in mice. Then, in order to test the consequences, they performed a series of behavioral tests designed to measure functions like memory, cognitive ability, and motor skills.
In one experiment, called the Morris Water Maze, mice had to learn to navigate to, and remember, the location of a hidden platform placed inside a pool with opaque water. During the first five days of testing, researchers found that the test group with an over-production of tomosyn had a significant problem in learning and memorizing the location of the platform, compared to a control group that received a placebo injection. And when the platform was removed from the maze, the test group spent less time swimming around the area where the platform once was, indicating that they had no memory of its existence. In comparison, the control group of mice searched for the missing platform in its previous location for two or even three days after its removal, notes Dr. Barak.
These findings were further verified by measuring electrical activity in the brains of both the test group and the control group. In the test group, researchers found decreased levels of transmissions between neurons in the hippocampus, a physiological finding that may explain the results of the behavioral tests.
Correcting neuronal processes
In the future, Dr. Barak believes that the ability to modify proteins directly in the brain will allow for more control over brain activities and the correction of neurodegenerative processes, such as providing stricter regulation in neuronal activity for epileptic patients or stimulating neurotransmitters to help with learning and memory loss in Alzheimer's patients. Indeed, a separate study conducted by the researchers demonstrates that mouse models for Alzheimer's disease do have an over-production of tomosyn in the hippocampus region, so countering the production of this protein could have a beneficial effect.
Now Dr. Barak and Prof. Ashery are working towards a method for artificially decreasing levels of the protein, which they believe will have the opposite effect on the cognitive ability of the mice. "We hypothesize that with an under-production in tomosyn, the mice will show a marked improvement in their performance in behavioral testing," he says.
Brain Images Could Reveal Guilt Someday soon, judgments of guilt...
Brain Images Could Reveal Guilt
Someday soon, judgments of guilt or innocence in a courtroom might be determined from a brain scan, scientists say.
Technologies for imaging the brain have advanced rapidly, to the point where it's possible to infer, for example, what object a person has stolen based on that person's neural activity. But how reliable is the science, and should it determine criminal fate? A panel of scientists and legal experts discussed these issues Saturday (June 1) at the World Science Festival, an annual celebration and exploration of science held here.
Gamma Cygni Region by Chuck Manges
Gamma Cygni Region by Chuck Manges
This Incredible Image Reveals Two Galaxies That Orbit the Milky...
This Incredible Image Reveals Two Galaxies That Orbit the Milky Way
Just as planets orbit Suns, galaxies can orbit each other. Now, NASA has created some unprecedented images of two such galaxies in the Milky Way's orbit, known as the Large and Small Magellanic Clouds (LMC and SMC). Here, you have an incredible view of these galaxies beneath the plane of the Milky Way.
knowledgethroughscience: The Crab Nebula is a supernova remnant...
The Crab Nebula is a supernova remnant in the constellation of Taurus.
It was first identified in 1731 by John Bevis, and independently rediscovered in 1758 by Charles Messier.
The nebula was the first astronomical object identified with a historical supernova explosion.
Saturn-Like Alien Planet Found by Little Telescope INDIANAPOLIS...
Saturn-Like Alien Planet Found by Little Telescope
INDIANAPOLIS — Tiny telescopes in Arizona and South Africa have spotted a Saturn-like planet in orbit around a star about 700 light-years from Earth.
Scientists using the Kilodegree Extremely Little Telescope (KELT) and other ground-based tools spied the alien planet as it passed in front of its star, a process called transiting.
ikenbot: The Planetary Nebula of NGC7027 Image by Delio...
The Planetary Nebula of NGC7027
Image by Delio Tolivia Cadrecha
A very young and dense planetary nebula located around 3,000 light-years away in the constellation Cygnus. It was discovered in 1878 by Édouard Stephan, using the 31 inch reflector at Marseille Observatory. [**]
Star-Studded Beauty in Gemini by Martin Campbell
Star-Studded Beauty in Gemini by Martin Campbell
Michio Kaku - Quantum Mechanics vs. General Relativity Michio...
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