Black Hole Thursdays.

Astronomers have for the first time developed a technique to view rapidly spinning disks of gas found near black holes.

Their observations allowed them to confirm the that the electromagnetic spectra of these accretion disks match what astronomers have long predicted, giving a boost of hard evidence to current quasar formation theory.

The team of researchers gazed into the night on Mauna Kea in Hawaii, looking through the United Kingdom Infrared Telescope. They were able to measure the spectrum of the accretion disk by getting rid of extra, interfering light, using a polarizing filter attached to the telescope.

Why exactly are polarized filters so special? Well, they aren't. It is the way that accretion disks emit light that lets the filter do its job. Accretion disks emit non-polarized light that doesn't care how its electrical field is aligned, known as direct light. But a small amount of accretion disk light reflects off gas very close to the black hole- this light is polarized. By only analyzing polarized light, researchers are able to ignore all the direct-light emitting irrelevant stuff, like dust particles and ionized gas.

Quasars are extremely bright, distant objects that also emit frenzied, massive amounts of energy. They are powerful, but until now no one has been able show that accretion disks falling toward black holes, particular near the horizon or black hole boundary, is the source of much that power.
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Another Side of Phobos

Today the camera eyes of the European Space Agency's Mars Express spacecraft will scrutinize the oddly shaped and pockmarked Phobos, as it makes its closest ever pass by the largest of Martian moons, gliding a mere 60 miles above its surface.

The spacecraft will use all of its high-tech tricks to perform a thorough examination, taking 3-D images, mapping with a high-resolution camera, making precise measurements of the Phobos' mass and composition, and unleashing its subsurface probing radar to study the the moon's insides. But Mars Express isn't done yet. It will travel again pass Phobos two more times this summer, collecting a wealth of new data.

Researchers are interested in Phobos because it is seen as a feasible compromise between sending astronauts to the moon, an extremely difficult but already accomplished feat, and sending astronauts to Mars, in what is likely to be a very dangerous, long, and tedious mission.

But that doesn't mean that Phobos is the back-up guy, the stand-in for space exploration. Aside from a considerably less risky mission, Phobos may be more interesting than previously thought. Some Scientists believe the moon might be harboring ice underneath its cratered surface. Plus, the origins of Phobos (along with Deimos- the other Martian moon) still aren't clear.

It is unknown if the moons were created at the same time as Mars, or if they are asteroids that wandered into Martian orbit later, in which case Phobo's exploration would be especially fruitful. Asteroids are known for having have lots of rich metals like metallic iron and nickel.

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What do a Dwarf Planet and a Polynesian God Have in Common?

They both share the same name: Makemake ( say it with me, MAH-kay, MAH-kay). The planet naming authority of the International Astronomical Union recently decided on the name, which comes from the Polynesian god of fertility and and creator of humanity.

The dwarf planet, is a member of the newly created plutoid subclass, where it joins Pluto and Eris. Like its plutoid brethren, Makemake is far off from the sun, lying beyond Neptune.


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What Earth and Moon Look like to Aliens.

Check out this video NASA's Deep Impact Sapcecraft made, of the moon passing in front of Earth, viewed from 31 million miles away. Kind of cool to think that this is how aliens might see us from somewhere off in the distant universe.

The clip combines several images of the moon rotating around the Earth in color. According to NASA, Deep Impact is the only spacecraft to show the moon passing around the earth in detail: you can actually see our oceans and continents, and the moon's large craters.
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On the Moon and Need a Telescope? Make Your Own!

Hauling stuff up to the moon can get heavy and expensive. That's why Peter Chen and other NASA researchers (right down the road in Greenbelt, MD) have been working on a way to build telescopes using moon materials.

They have already managed to make a telescope mirror out of moon dirt (called "regolith" in space jargon), carbon nanotubes, and a pinch of epoxy. In something like lunar pottery, they spun the concrete-like mixture into a parabolic bowl shape, characteristic of a telescope mirror.

The bowl was placed into a vacuum chamber, thinly coated it with aluminum to make a mirror 1 foot in diameter. So far the method used by Chen and others is working, lunar telescope builders wouldn't even need a vacuum chamber, thanks to the moon's lack of atmosphere.

There are a few challenges however, such as lunar dust contamination that builders would have to somehow prevent while working. Plus, a spinning table would still have to be loaded onto rockets from earth and carried up to make the parabolic bowl.

The next part of the project aims to solve the problems of lunar dust, by creating an even larger mirror (1.64 foot by 3.23 foot) using simulated lunar dust. Improving the quality of the mirror and perfecting it's surface are also goals.
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A Paucity of Pee.

"Valuable" is not the first adjective that comes to mind when prompted to describe urine, but the stuff is in high demand at NASA's Johnson Space Center in Houston.

Developers of the Orion Space Capsule are working on a new-and-improved space toilet. Reliability is essential, as the Orion will remain stationed in unoccupied space for up to 6 months while scientists are busy working on the moon.

More specifically, scientists are trying to figure out how to the solve the difficult problems of urine acidity and elimination of stored urine. Naturally, they need authentic samples to ensure optimal design. About 8 gallons a day, 7 days a week's worth of urine is need.

Obtaining copious amounts of pee is apparently not easy. NASA recently sent out an internal memo asking workers to do their part for space toilet technology, by giving daily contributions of urine from July 21 to 31.
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6 Billion Year Old Particles Maintain Weight

In the case of subatomic particles, the phrase "still the same after all these years" should be taken literally. As German astrophysicists recently discovered, the mass ratio of the proton and the electron is the same as it was 6 billion years ago.

Specifically, protons weighed 1,836 times more than electrons back then, and they still do!The researchers who performed the study had originally detected ammonia in a very far off galaxy, by observing its absorption of radio waves from a powerful bundle of energy called a quasar, located behind the galaxy.

Because light from such a distant object takes time to travel to us here on earth, the farther away scientists probe the universe, the farther back into the past they see. Therefore, they actually viewed ammonia as it was millions and millions of years ago.

Because of its pyramid-like structure, ammonia behaves differently than other molecules when absorbing the energy from radio waves. In a feat of subatomic gymnastics, an ammonia molecule actually flips inside out, its three hydrogens moving from the bottom of the pyramid to the top, while its nitrogen resumes the base position.

As researchers knew, the key to the flip lies in the ratio between the mass of the proton and the electron. They compared the ammonia absorption data to other molecules within the same galaxy and found that absorption was basically the same, indicating that the proton/electron mass ratio had not changed.

We all know subatomic particles are really, really tiny, so who cares what they weigh? Turns out that question is a loaded one. Many scientists believe that changes in particle masses provide evidence that universal constants like the speed of light, are well, not so constant after all. This idea might provide explanations for dark energy, and hidden extra dimensions proposed by string theory.
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Weekend Satellite Sighting

If you are living in North America or Europe, tis the season for spotting the International Space Station (ISS)!

Websites like NASA's Skywatch can tell you the viewing schedule for your area by entering a zip code.

High altitude- satellites like the ISS are lit up by reflecting sunlight, making them visible against a dark night sky. Only at this time of year are the nights short enough to view orbiting objects that remain close to earth.

Luckily, the ISS is enormous (when completed it will have a mass of 250 tons), making it much easier to see than most other artificial satellites. It also circles the earth about every 90 minutes, so those living in optimal locations might be able to see the station up to 6 times in one night.

July 17 through the 21 is the best time frame for viewing, either 45 to 90 minutes before sunrise, or 45 to 90 minutes after the sunset, when the ISS appears at a high arc across the sky. You might even see a super-bright satellite flare, giving the impression that a trail of is light streaking across the sky.
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Moon Glass Pebbles Reveal Water

A wise man once said, "Keep yer' moon pebbles, they may be important someday". All right, so maybe no one at NASA actually uttered those words, but I'm sure scientists are thankful they were heeded.

A team of scientists has found extremely tiny amounts of water, around 46 parts per million in glass pebbles from the moon, brought to earth by Apollo missions in the late 1960s and early 1970s.

These watery gems provide strong evidence that the inside of the moon was once gushing with liquid water. That's in stark contrast to how most of us think about our dear old piece of cheese, as dusty and dry. So how much is a part per million? Parts per million ( or billion or trillion) are measures of concentration. They allow scientists to determine how much of a substance is in another substance, using a limited sample.

If the glass pebble were cut into a million pieces, only about 46 of them would be made of water. While this may seem mind-bogglingly small, the finding is tantalizing proof of water that must have once existed on the moon in ample supply.

Scientists detected the water by using a technique called secondary ion mass spectrometry (SIMS), and then confirmed then presence of hydrogen in the samples through rigorous testing.

The discovered water sheds new light on a widely accepted theory of moon formation, that a giant object slammed into the earth some 4.5 billion years ago, breaking off a molten chunk that cooled and created the moon. The impact of this collision would have quickly vaporized any water. Moreover, the findings indicate that water must have been present on earth before the collision.
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The Earth is Screaming

Astronomers have recently confirmed that the earth sounds like a three year old throwing a tantrum.

Recordings from space have captured the unpleasant noise, which may be heard by extraterrestrials.

We already know the planet emits a quiet hum, most likely caused by our continuously moving oceans, or our turbulent atmosphere. The radio waves that cause the screeching sounds are created by particles that collide as the solar wind passes through the earth's magnetic field.

New data from the European Space Agency's Cluster mission show that the radio waves, called Auroral Kilometric Radiation, burst into space from the earth in narrow, flat beams.

New technology has enabled researchers to pinpoint exactly where the noise is coming from. Scientists located 12,000 spots around the earth that send out the radio waves, each is about the size of a large city.

So why don't we hear them? A charged atmospheric layer called the ionosphere blocks the radio waves, preventing them from reaching the earth. But that doesn't mean the waves aren't strong.-they are 10,000 times greater that the strongest military signal, that's enough to drown out every radio station on the planet.
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Tiny Telescopes

The year is 1908, the place is Tunguska, Russia, where a meteoroid or comet blasted into the earth's atmosphere and shattered to pieces, creating a 10-15 megaton explosion.

It downed 80 million trees over the Siberian forest, and scientists are certain that the sheer impact of the explosion would have destroyed any major world city.

In two years, we'll all be able to sleep a little easier at night, knowing that the earth's new watchdog, NEOSSat ( Near Earth Object Surveillance Satellite) is in orbit. Roughly the size of a suitcase, this tiny telescope will be perched 800 km above the earth.

Its sole job is detecting asteroids and other harmful objects before they collide with the earth. For 5 years it will snap photos of possible dangers and beam them back to earth, operating on less power than your average light bulb.

Developed by Canadian scientists, the solar-powered NEOSSat is capable of seeking out objects close to the sun. This is a huge advantage over ground based surveillance telescopes, which are severely limited by bad weather and interfering sunlight.

The telescope will also serve as an early warning system for orbiting space junk traveling in the path of telecommunications satellites. Smashed satellites can kill cable TV, telephones, GPS, and maybe most important of all-access to money through banking systems. But fear not, NEOSSsat can predict space junk collision paths and send warnings to move satellites.

While an event like the 1908 explosion is rare, scientists estimate that there are currently at least 95,000 orbiting meteoroids larger than the one that hit Tunguska.
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Mystery Crash Into Mars

Way back in 1984, when the Berlin Wall was still erect and everyone felt obliged to read George Orwell, a few astrogeologists came up with a theory to explain why the northern side of Mars is smooth and flat, while the southern side is marred with craters and highly elevated.

They proposed that something really large slammed into Mars, creating a creating split almost down the middle of the planet. Their ideawas influenced by another theory circulating at the time; that the moon formed by a chunk of Mars breaking off after a massive impact.

The major crash theory didn't develop much beyond that. After sitting on some dusty academic shelf for the past 25 years it has finally been revived, thanks to new evidence from recent research. Scientists now believe that something similar to an asteroid or a comet smacked into Mars about 4 billion years ago.

Moreover, the giant crater left over from the impact may be the largest in our solar system, about the size of Asia, Europe, and Australia combined. The sheer size and shape of the crater provides conclusive evidence that Mars must have experienced a significant impact. A small part of the crater was actually uncovered in the 1980s (dubbed the Borealis Basin), but because a large portion is hidden under thick layers of lava, not one could map it entirely until now.

Researchers analyzed data from two Mars orbiters, studying crust thickness, surface elevations, and the gravitational pull. Using this information, they were able to reveal what lay beneath the lava. What they found was a huge scar that stretches between the two very different terrains of the planet. It covers about 40% of the surface.

A model simulation was also created to determine the size of the mystery asteroid or comet and exactly where it hit. Gaining clues into the impact, researchers figured out what happened in the aftermath. By bombarding a model simulation of Mars with various sized objects, they were able to pinpoint the conditions needed to result to in the formation of such a huge crater without melting the entire planetary crust.
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The Planet Hunt

The search has begun for a planet just like earth-from lush green fields to mountains to cold deep rivers and waterfalls.

Of course, other earths would have to be made up of elements similar to our own, and orbit at a special distance required for liquid water to exist on its surface, called the habitable zone.

Astronomers are using new technology to scan other star systems for clues to unexplored earths. They are now capable of viewing faint wobbles in a star's motion, that are caused by the gravitational pull of an orbiting planet.

Advanced telescopes also let researchers watch for a dimming of light in stars that occurs as an orbiting planet passes in front of it. Thousands of stars can be monitored simultaneously.

In the winter of 2009 NASA will launch its Kepler mission, designed to seek out planets orbiting massive stars, like how our earth orbits the sun. Kepler will keep an eye out for starlight dimming in 100,000 stars.
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Must Have Been Ice, But It's Over Now

NASA's Mars Phoenix Lander recently dug a trench on the Martian Landscape and captured photos of little chunks of white matter. Four days later, the mysterious stuff had disappeared. Scientists believe it was ice that went through the same process the snowman in your front yard does each winter; it evaporated.

Previously, there had been an ongoing debate as to whether or not the material was salt, but the disappearance confirmed that it must indeed be ice.

More ice surfaces are likely to be revealed as the robotic arm continues its work. Early on it refused to continue digging, even when it was told multiple times to explore a "polygon" region nearby the lander site. Halting is how the Phoenix is programmed to respond when it hits a hard surface beneath the soil.

Polygons are formed when permafrost (permanently frozen soil beneath the ground's surface) repeats a cycle of freezing and thawing, over many thousands of years. The result makes patterns comprised of cracks and wedges into polygon-like shapes in the ground.

The finds provides somewhat of a morale boost for researchers in charge of Phoenix, as previous digs yielded nothing but soil. The goal of the mission is to search the the polar region of Mars for evidence that this part of the red planet could support life.
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Magnifying Moon Tricks

While the moon is actually never full, this evening, Wednesday June 18th, it will seem abnormally huge to most people. Don't worry, it's only your mind playing tricks on you. This optical illusion, known as the Ponzo illusion, makes it seem as if the moon is bigger when it's near the horizon. The effect is exaggerated during the "full" moon.

Unfortunately, human eyesight can't be trusted when dealing with extremely large distances. The moon is not any larger overhead than it is near the horizon. Mario Ponzo first determined that our minds sometimes gauge the size of an object based on the background behind it. Because we perceive the sky as an extended dome, the moon appears to be very distant when on the horizon. On the other hand, things like clouds and airplanes, which are viewed directly overhead appear (and really are) much closer. So naturally. we tend to think that the moon is closer when viewed overhead too.

But the idea of the moon being farther away because it is on the horizon rather than overhead is only an illusion, as the moon is beyond the sky and hundreds of thousands of miles away, far enough to remain unchanging. Since during a full moon its size doesn't appear to decrease, and yet it is located on the horizon, we are tricked into thinking it must be bigger. And that is in fact what we see.

NASA says that the moon illusion is particularly strong and long-lasting during the solstice, two days before the start of summer in Northern Hemisphere.
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Cleaning Up Cosmic Dust

I imagine the earth must be fairly dusty by now, as it receives about 40,000 tons of dust particles from space each year. But once in awhile (NASA has been collecting dust since 1982), a unique mineral is found among the clouds of interplanetary dust.

Scientists recently discovered a new mineral, which is thought to have originated from a comet, although its properties are so unusual that no one is really sure where it comes from.

Space dust is particularly interesting because its composition holds clues as to how our solar system is formed. Very tiny clues. The grains of the mineral, a manganese silicide named Brownleeite (named after astronomer Donald E. Brownlee) were approximately 1/10,000 of an inch in size. The researchers used a transmission electron microscope to study the mineral's nano-scale crystal structure and chemical composition.
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Bending Starlight Solved by Non-Physicists

Two mathematicians fiddling around with an extension of the fundamental theorem of algebra had no idea of the significant implications their work held for gravitational lensing, a prediction of Einstein's general theory of relativity.

Turns out Dmitry Khavinson and Genevra Neumann proved physicist Sun Hong Rhie's theory on gravitational lensing. Gravitational lensing explains the deceptive behavior of light traveling at extremely far distances.

A gravitational lens forms when distant light from a particularly bright source, like a star, "bends" in both directions around a massive object. This cosmic optical illusion misleads the observer (usually here on earth), into thinking the light originates from 2 sources, when in fact there is only one. What looks like 2 different stars is actually the same star.

The light-tricks depend on where the massive object lies and how many massive objects there are. A star looks like a circle when the massive object is directly between the star and the observer. A multitude of objects means the observer will view what appears to be a multitude of stars.

Rhie had been trying to determine how many mirages of stars could be created by the bending of light. She calculated that four massive objects lead to 15 ostensible stars, coming up with the formula 5n-5 stars, where n is the number of massive objects. Unfortunately, being "pretty sure" of something doesn't cut it in science: she needed cold proof.

Over on the west coast, mathematican Jefferey Rabin stumbled across Rhie's work and took a stab at it. He spent months on the problem with little success. In a simple twist of fate, someone in Rabin's department had left an article on the printer. Passing by, Rabin read it and realized someone had solved the problem, but with purely mathematical aims; they were completely unaware of gravitational lensing.

That article was Khavinson and Neumann's, and their work with rational harmonic functions had unknowingly proved Rhie's assertion. Another example of how important the dissemination of scientific knowledge is! Accidental discoveries make for great stories.
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Rad 1970's Space Colonies

I couldn't resist posting these artist's renditions of life in space, from a time when NASA was seriously contemplating space colonies.

Check out more space colony artwork from NASA here.
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Cosmic Identity Crisis Resolved

Pluto, formerly known as the ninth planet in our solar system, has officially been given a new label: plutoid. The International Astronomical Union (IAU) decided on the name yesterday, which distinguishes all dwarf planets located farther from the sun than Neptune.

Dwarf planets are not-quite-planets, massive enough to assume a near spherical shape from self-gravitational force, but not large enough to have their own orbital zone, or become gravitationally dominant like real planets.

The discovery of Eris in 2003 triggered the reclassification craze. Eris, a dwarf planet larger and farther from the sun than pluto, is currently the only other plutoid aside from pluto.

Astronomers examining Eris' characteristics became aware of certain discrepancies in bodies characterized as planets. The demotion of pluto to a nameless dwarf planet by the IAU Committee on Small Body Nomenclature followed shortly in 2006.
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Tangled up in Quantum

Scientists perform experiments in order to test a theory. If enough data is generated to support a claim, that claim is usually declared true. But what if the experiment continuously gave a predicted result only because the scientist was on earth? Perhaps a different outcome occurs in space.

This is the argument behind a recent proposal to launch a mission called Space-QUEST (Quantum Entanglement for Space Experiments). Anton Zeilinger of the University of Vienna submitted the proposal to the European Space Agency. He wants to perform quantum entanglement experiments for the first time in space, at the International Space Station (ISS).

Quantum entanglement describes the complex way particles are linked together, such that one cannot exist without the other, regardless of distance. Superposition, the ability to get two different but related measurements, is central to an understanding of quantum entanglement.

According to quantum theory, measurements made on linked particles, no matter how far away, are instantaneously influenced by one another. Einstein notably poked fun at the idea of instantaneous influence, labeling it "sooky action at a distance", as it violated certain predictions of special relativity. He disliked and dismissed quantum entanglement entirely. This is summed up in the EPR paradox, a thought experiment by Einstein, Podolsky, and Rosen.

But numerous short-distance experiments on earth have agreed with quantum theory and provided strong evidence of quantum entanglement. The experiments involved sending two entangled particles, for example photons, to separately located scientists, who then take measurements. Despite this, there are some who believe that the results are a false positive. Quantum entanglement may only work on earth, where distance is limited. Maybe something different happens to entangled photons over enormous ground-to-earth distances. Zeilinger is determined to find out.

Since he's already proven that single photons can be detected on the ground by bouncing them off orbiting satellites, he plans to separate two entangled particles at a distance never before tested, one particle to an orbiting astronaut in space (At the ISS), and the other somewhere on the ground, here on Earth. Maybe Einstein will be proven right.

And yes, the title alludes to tangled up in blue (arguably my favorite Dylan song).
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