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7 Irregularities that suggest Earth’s Moon was engineered

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Brightest explosion ever seen in the universe

Brightest explosion ever seen in the universe

By Denise Chow

Published November 22, 2013

  • brightest-gamma-ray-burst

    An unusually bright gamma-ray burst produced a jet that emerged at nearly the speed of light. (NASA/SWIFT/CRUZ DEWILDE)

  • gamma-ray-burst-swift-nasa

    A gamma-ray burst that exploded in April 2013 is the most luminous object in the field, as seen in this image from NASA’s Swift satellite. All the other objects seen in the image are stars from our own galaxy, while the gamma-ray burst is milli (NASA/SWIFT SATELLITE)

  • gamma-ray-burst-swift

    Close-up image of the brightest gamma-ray burst ever seen, taken in April 2013 by the ultraviolet/optical telescope on NASA’s Swift satellite. (NASA/SWIFT SATELLITE)

A mysterious blast of light spotted earlier this year near the constellation Leo was actually the brightest gamma-ray burst ever recorded, and was triggered by an extremely powerful stellar explosion, new research reports.

On April 27, several satellites — including NASA’s Swift satellite and Fermi Gamma-ray Space Telescope — observed an unusually bright burst of gamma radiation. The explosion unleashed an energetic jet of particles that traveled at nearly the speed of light, researchers said.

“We suddenly saw a gamma-ray burst that was extremely bright — a monster gamma-ray burst,” study co-author Daniele Malesani, an astrophysicist at the Niels Bohr Institute at the University of Copenhagen in Denmark, said in a statement. “This [was] one of the most powerful gamma-ray bursts we have ever observed with the Swift satellite.” [Top 10 Strangest Things in Space]

The gamma-ray burst was described in a series of studies published online Thursday in the journal Science.

‘The exploding matter was traveling at [nearly] the speed of light.’

– Giacomo Vianello, a postdoctoral scholar at Stanford University

Gamma-ray bursts, or GRBs, are the most powerful type of explosions in the universe and typically mark the destruction of a massive star. The original stars are too faint to be seen, but the supernova explosions that signal a star’s death throes can cause violent bursts of gamma radiation, researchers said.

Gamma-ray bursts are usually short but extremely bright. Still, ground-based telescopes have a tough time observing them because Earth’s atmosphere absorbs the gamma radiation.

The extremely bright gamma-ray burst seen earlier this year, officially dubbed GRB 130472A, occurred in a galaxy 3.6 billion light-years away from Earth, which, though still far away, is less than half the distance at which gamma-ray bursts have previously been seen. This closer proximity to Earth enabled astronomers to confirm for the first time that one object can simultaneously create a powerful GRB and a supernova explosion.

“We normally detect GRBs at great distance, meaning they usually appear quite faint,” study co-author Paul O’Brien, an astronomer at the University of Leicester in the United Kingdom, said in a statement. “In this case, the burst happened only a quarter of the way across the universe — meaning it was very bright. On this occasion, a powerful supernova was also produced — something we have not recorded before alongside a powerful GRB — and we will now be seeking to understand this occurrence.”

The jet produced by the gamma-ray burst was formed when a massive star collapsed on itself and created a black hole at its center. This generated a blast wave that caused the stellar remnants to expand, producing a glowing shell of debris that was observed as an extremely bright supernova explosion.

After analyzing properties of the light produced by the gamma-ray burst, scientists determined that the original star was only three to four times the size of the sun, but was 20 to 30 times more massive. This extremely compact star was also rapidly rotating, the researchers said.

The GRB was the brightest and most energetic ever witnessed and triggered dynamic internal and external shock waves that are still not well understood. Though scientists have a clearer view of the violent explosion, mysteries remain. For instance, space telescopes detected more photons and more high-energy gamma-rays than theoretical models predicted for a gamma-ray burst of this magnitude.

Researchers are still investigating why the energy levels seen with GRB 130472A do not quite match predictions from existing models of gamma-ray bursts. Their results could lead to more refined theories about how particles are accelerated, which could help astronomers better predict the behavior of cosmic events.

“The really cool thing about this GRB is that because the exploding matter was traveling at [nearly] the speed of light, we were able to observe relativistic shocks,” study co-author Giacomo Vianello, a postdoctoral scholar at Stanford University in California, said in a statement. “We cannot make a relativistic shock in the lab, so we really don’t know what happens in it, and this is one of the main unknown assumptions in the model. These observations challenge the models and can lead us to a better understanding of physics.”

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Lunar Craters Covering Moon’s Near Side Are Bigger Than Far Side

Lunar Craters Covering Moon’s Near Side Are Bigger Than Far Side Due To Hemisphere Differences

natureheader  |  By Davide CastelvecchiPosted: 11/08/2013 9:07 am EST  |  Updated: 11/08/2013 9:43 am EST

 
lunar craters

When the Soviet probe Luna 3 sent back the first shots of the dark side of the Moon, they showed that it was noticeably more pockmarked by craters than the near side. The nearside crust, by contrast, had more large, shallow basins. More than 50 years after those images first baffled researchers,a study published today in Science explains the observations.

Some theories suggest that the large basins on the near side were caused by impacts from asteroids bigger than those that caused the craters on the far side. But the latest study suggests that the observed basins do not accurately reflect the size of the initial impact, because as asteroids battered the lunar surface in the early history of the Solar System, the Moon’s warmer and softer nearside crust melted like butter, producing giant lava flows that filled the impact craters and transformed them into basins.

To improve on previous estimates of the size and distribution of basins, the team behind the study used data from NASA’s Gravity Recovery and Interior Laboratory mission (GRAIL), two satellites that since 2011 have been orbiting the Moon and mapping subtle variations in the strength of its gravitational field. Basins are characterized by thinner crust, says first author Katarina Miljković, a planetary scientist at the Paris Institute of Earth Physics. The team used GRAIL’s gravity mapsto find such thin crust and measure the true size of the basins.

“We didn’t have to look at topography nearly at all, just at the crust thickness,” says Miljković. The researchers found that although both sides of the Moon had the same total number of impact craters, the near side had eight basins larger than 320 kilometers in diameter, whereas the far side had only one.

 Hot hit

 The asteroid bombardment should have battered both sides equally, Miljković points out. The asymmetry could have arisen from comparatively small objects punching above their weight on the near side, producing basins more easily than on the far side.

Simulations showed that if the largest dark area on the near side — the plain of volcanic rock known as Oceanus Procellarum — was hundreds of degrees hotter than crust on the far side, impacts there would produce basins up to twice as large as impacts from similar-sized bodies on the far side (see video above).

And indeed, around 4 billion years ago, or 500 million years after the Moon formed, the near side could have been warmer than the far side. Researchers looking at the near side have detected the presence of radioactive isotopes; their decay would have heated up the rock, explains study co-author Maria Zuber, a planetary scientist at the Massachusetts Institute of Technology in Cambridge and principal investigator of GRAIL.

The findings fit well with the observations, but “there is no consensus” as to what caused the startling asymmetry in isotope content between the near side and the far side, says Jeffrey Taylor, a lunar scientist at the University of Hawaii in Honolulu. One leading theory posits that material rich in radioactive elements rose in a gigantic volcanic plume and formed a magma basin; another that it came from a collision with a sister moon around 1,000 kilometers in diameter.

William Bottke, a lunar scientist at the Southwest Research Institute in Boulder, Colorado, says that the work could lead researchers to revise just how dramatic asteroid bombardments were in the early Solar System. “This can be used to more accurately derive what the small-body populations were like four billion years ago.”

This story originally appeared in Nature News.

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Super-Earth Alien Planet May Have ‘Plasma’ Water Atmosphere

Super-Earth Alien Planet May Have ‘Plasma’ Water Atmosphere

Space.com  |  By Nola Taylor ReddPosted: 10/02/2013 9:21 am EDT  |  Updated: 10/03/2013 12:01 pm EDT

A nearby alien planet six times the size of the Earth is covered with a water-rich atmosphere that includes a strange “plasma form” of water, scientists say.

Astronomers have determined that the atmosphere of super-Earth Gliese 1214 b is likely water-rich. However, this exoplanet is no Earth twin. The high temperature and density of the planet give it an atmosphere that differs dramatically from Earth.

“As the temperature and pressure are so high, water is not in a usual form (vapor, liquid, or solid), but in an ionic or plasma form at the bottom the atmosphere — namely the interior — of Gliese 1214 b,” principle investigator Norio Narita of the National Astronomical Observatory of Japan told SPACE.com by email. [The Strangest Alien Planets (Gallery)]

Using two instruments on the Subaru Telescope in Mauna Kea, Hawaii, scientists studied the scattering of light from the planet. Combining their results with previous observations led the astronomers to conclude that the atmosphere contained significant amounts of water.

A wellspring of exotic water

Located 40 light-years from the solar system in the constellation Ophiuchus, the planet orbits its cooler, low-mass M-type star once every 38 hours, 70 times closer than Earth is to the sun.

Its close proximity means that its temperatures reach up to 540 degrees Fahrenheit (280 degrees Celsius). Six times as massive as Earth, Gliese 1214 b is less than three times as wide, falling between the Earth and the solar system’s ice giants Uranus and Neptune in size.

The high temperatures of the planet may affect the hydrogen and carbon chemistry, which could produce a haze in the atmosphere. But determining if the weather is clear or perpetually overcast on Gliese 1214 b would be difficult, as differences in the two atmospheres are small.

“At high pressure and high temperature, the behavior of water is quite different from that on the Earth,” Narita said. “At the bottom of the water-rich atmosphere of Gliese 1214 b, water should be a super-critical fluid.”

super earth waterArtist’s rendition of the relationship between the composition of the atmosphere and transmitted colors of light of an alien planet. Top: If the sky has a clear, upward-extended, hydrogen-dominated atmosphere, Rayleigh scattering disperses a large portion of the blue light from the atmosphere of the host while it scatters less of the red light. As a result, a transit in blue light becomes deeper than the one in red light. Middle: If the sky has a less extended water-rich atmosphere, the effect of the Rayleigh scattering is much weaker than in a hydrogen-dominated atmosphere. In this case, transits in all colors have almost the same transit depths. Bottom: If the sky has extensive clouds, most of the light cannot be transmitted through the atmosphere.

Unlike terrestrial planets, the super-Earth doesn’t have a solid surface, making the height of the atmosphere difficult to define. Instead, atmospheric scientists introduce a concept called the scale height, a height determined by changes in the increase or decrease of atmospheric pressure by a set amount. On Earth, the scale height is about 6 miles (10 kilometers), while on Gliese 1214 b it is three times deeper, according to Narita.

“We predict that ionic or plasma water can be seen deep inside the planet,” Narita said. “However, we may not be able to find hot ‘ice’ — high pressure-ices — inside of Gliese 1214 b.”

Originally discovered in by the MEarth Project, which tracks more than 2,000 low-mass stars in search of planets, Gliese 1214 b was confirmed by the European Space Agency’s High Accuracy Radial velocity Planet Searcher in Chile.

As a planet travels across the face of its star, or transits, it blocks the star’s light slightly, allowing scientists to determine characteristics about it based on how much the light dims.

Though water is often considered a necessary ingredient for life by scientists, Narita doesn’t think that the super-Earth will be promising due to its close orbit, which lies within the star’s habitable zone, the region where liquid water can exist.

“Although water vapor can exist in the atmosphere, liquid water — namely oceans — would not exist on the surface of this planet,” he said. “So unfortunately, we do not think this planet would be habitable.”

Narita’s team intends to continue studying the planet with spectroscopic observations in the visible wavelength, and anticipates that other astronomers will follow.

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NASA abandons hope for failing Kepler space telescope

NASA abandons hope for failing Kepler space telescope

Published August 15, 2013

FoxNews.com
  • NASA Kepler Space Telescope

    An artist’s interpretation of the Kepler observatory in space. (NASA)

  • Newly discovered planets named Kepler-62e and -f

    Two newly discovered planets named Kepler-62e and -f. Scientists using NASA’s Kepler telescope found the distant planets, which they say are in the right place and are the right size for potential life. (AP PHOTO/HARVARD SMITHSONIAN CENTER FOR ASTROPHYSICS)

Efforts to save a $600 million tool in NASA’s quest for life elsewhere in the universe have been unsuccessful, the space agency said — but there’s still life left in the robotic planet hunter.

In May, a specialized gyroscopic wheel used to point the Kepler Space Telescope toward the sun failed, the second such failed wheel. And despite months of analysis and testing, the spacecraft will never be restored to working order. But despite the breakdown, Kepler has proven a remarkable success, NASA said.

“Kepler has made extraordinary discoveries in finding exoplanets including several super-Earths in the habitable zone,” said John Grunsfeld, associate administrator for NASA’s Science Mission Directorate in Washington. “Knowing that Kepler has successfully collected all the data from its prime mission, I am confident that more amazing discoveries are on the horizon.”

NASA said its efforts will now turn to making the most of the research craft while it still can.

‘I’m confident that more amazing discoveries are on the horizon.’

– John Grunsfeld, associate administrator, NASA’s science mission directorate 

Kepler is the first NASA mission capable of finding Earth-size planets in or near the habitable zone, the range of distance from a star where the surface temperature of an orbiting planet might be suitable for liquid water. Launched in 2009, it has discovered thousands of such planets, including a pair just 1,200 light years away.

Called Kepler-62-e and Kepler-62-f, the news of their discovery came in April. But shortly after, Kepler’s mission ran into trouble.

Kepler is powered by four solar panels, and the spacecraft must execute a 90-degree roll every 3 months to reposition them toward the sun while keeping its eye precisely aimed. Kepler launched with four wheels to control that motion — two of them have now failed.

On Aug. 8, engineers conducted a system-level performance test to evaluate Kepler’s current capabilities. They determined that the wheel which failed last year can no longer provide the precision pointing necessary for science data collection. The spacecraft was returned to its point rest state, which is a stable configuration where Kepler uses thrusters to control its pointing with minimal fuel use.

“At the beginning of our mission, no one knew if Earth-size planets were abundant in the galaxy. If they were rare, we might be alone,” said William Borucki, Kepler science principal investigator at NASA’s Ames Research Center in Moffett Field, Calif. “Now at the completion of Kepler observations, the data holds the answer to the question that inspired the mission: Are Earths in the habitable zone of stars like our sun common or rare?”

Kepler will continue working, and NASA will look to reduce fuel consumption to extend the lifespan of the spacecraft. For example, a different mode of steering Kepler will enable NASA to extend its life by years, explained Charles Sobeck, deputy project manager with Ames Research Center.

“We’re not down and out. The spacecraft is safe, it is stable,” Sobeck said in May. And regardless, Kepler is already a win for NASA.

“The mission itself has been spectacularly successful,” he added. Most other scientists agree.

The quest for “exoplanets” has generated enormous interest among the public and with scientists. And it will continue. A second mission will launch in 2017 and will use the same method that Kepler has used to continue the mission; it will seek the closest exoplanet — which may be under two dozen light years away.

The James Webb Space Telescope will also help in the quest for life in the universe.

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Sun’s 8.2-billion-year-old twin found

Sun’s 8.2-billion-year-old twin found

By Irene Klotz

Published August 28, 2013

Discovery News
  • sunstwin2.jpg

    This image tracks the life of a Sun-like star, from its birth on the left side of the frame to its evolution into a red giant star on the right. (ESO/M. Kornmesser)

  • SUNSTWIN.jpg

    This image shows solar twin HIP 102152, a star located 250 light-years from Earth in the constellation of Capricornus (The Sea Goat). (ESO/Digitized Sky Survey 2. Ack: Davide De Martin)

About 250 light-years away in the constellation Capricornus (The Sea Goat) lies a star that looks awfully familiar.

Known as HIP 102152, the star is a virtual twin of our sun, which in and of itself is not so unusual. But HIP 102152 is older than our 4.6-billion-year old sun — by nearly 4 billion years, making it the oldest solar twin found to date.

“It is important for us to understand our sun in the proper context of stellar astronomy and to identify which of its properties are unique and normal, to predict what its fate may someday be,” astronomer TalaWanda Monroe, a postdoctoral fellow at the University of San Paulo in Brazil, wrote in an email to Discovery News.

New high-definition footage from the Solar Dynamic Observatory shows coronal mass ejections, huge eruptions of plasma blasting into space before showering back down on the sun’s surface.

NASA’s Solar Dynamics Observatory

With human lifespans so limited, seeing the sun in context means astronomers must find stars with similar mass, chemical composition, temperature and other characteristics. From that, they can then extrapolate information about our sun, such as how bright it shined in its youth and how different its radiation may be in the future.

“HIP 102152 is an ideal star to anchor the end of the timeline,” Monroe said.

Stars like the sun last about 10 billion years before running out of hydrogen fuel for their thermonuclear reactions. They then cool and expand into what is known as a “red giant” phase.

HIP 102152 may be like the sun in another way as well. Unlike other solar twins, chemical analysis of HIP 102152’s light shows a good match to the sun’s, including a telltale sign of possible rocky planets.

Scientists found elements common in dust and meteorites missing from HIP 102152’s light — “a strong hint … that the elements may have gone into making rocky bodies and/or planets” around the star,” Monroe wrote.

So far, attempts to search for any orbiting planets have not been successful.

The group also was able to make a direct tie between the amount of lithium in a star and the star’s age.

Some previous studies suggested a low lithium content may indicate the presence of giant planets, said astronomer Jorge Melendez, also with the University of San Paulo.

The new research shows that as a solar-type star ages, its lithium content decreases.

“We could use lithium to estimate the age of a star, something that is very difficult to obtain,” Melendez wrote in an email to Discovery News.

The discovery, made with the European Southern Observatory’s Very Large Telescope, was unveiled at press conference on Wednesday and is the subject of an upcoming paper in Astrophysical Journal Letters.

Read more: http://www.foxnews.com/science/2013/08/28/sun-82-billion-year-old-twin-found/?intcmp=trending#ixzz2eKKEX1LY

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Space-time loops may explain black holes

Space-time loops may explain black holes

Black holes can't fully be described by general relativity, but physicists hope to understand the inner workings of these strange objects by applying a theory called loop quantum gravity.

Black holes can’t fully be described by general relativity, but physicists hope to understand the inner workings of these strange objects by applying a theory called loop quantum gravity. / FELIPE ESQUIVEL REED

Physics cannot describe what happens inside a black hole. There, current theories break down, and general relativity collides with quantum mechanics, creating what’s called a singularity, or a point at which the equations spit out infinities.

But some advanced physics theories are trying to bridge the gap between general relativity and quantum mechanics, tounderstand what’s truly going on inside the densest objects in the universe. Recently, scientists applied a theory called loop quantum gravity to the case of black holes, and found that inside these objects, space and time may be extremely curved, but that gravity there is not infinite, as general relativity predicts.

This was the first time scientists have applied the full loop quantum gravity theory to black holes, and the results were encouraging, researchers said.

“What they have done is a major step, because they have been able to provide a much more complete description of what really happens near the black hole singularity using loop quantum gravity,” said Abhay Ashtekar, a physicist who studies loop quantum gravity at Pennsylvania State University, who was not involved in the new research.”We still don’t have a clear picture of the details of what happens. So it is opening a new door that other people will follow.” [Images: Black Holes of the Universe]

A black hole is created when a huge star runs out of fuel for nuclear fusion and collapses under its own gravity. The star’s outer layers are expelled, and its core falls in on itself, with the pull of gravity becoming ever stronger, until what’s left is the core’s mass condensed into an extremely small area. According to general relativity, this area is a single point of space-time, and the density there is infinitely large — a singularity.

But most scientists think singularities don’t really exist, that they’re just a sign that equations have broken down and fail to adequately describe reality. Loop quantum gravity appears to be an improvement on general relativity in describing black holes because it doesn’t produce a singularity.

The idea is based on the notion of “quantization,” which breaks an entity up into discrete pieces.Whilequantum mechanics says atoms exist in quantized, discrete states, loop quantum gravity posits that space-time itself is made of quantized, discrete bits, in the form of tiny, one-dimensional loops.

“The loop means the fundamental excitations of space-time themselves are one-dimensional in nature,” said Jorge Pullin, a physicist at Louisiana State University, who co-authored the new study with Rodolfo Gambini of the University of the Republic in Montevideo, Uruguay. “The fundamental building block is a loop, or network of loops. For a visual image, think of a mesh fabric.”

This way of portraying space-time changes fundamental physics, especially in extreme settingssuch as black holes or the Big Bang — which is thought to have birthed the universe. The Big Bang, like black holes, is indescribable under general relativity, understood only as a singularity.

“The subject really took off in 2005 when it was realized loop quantum gravity can naturally resolve the Big Bang singularity and that quantum space-time is much larger than what Einstein envisioned,” Ashtekar told SPACE.com.

Pullin and Gambini said their work is just a preliminary step, far from a full description of the true complexity of black holes.

“This model we’ve done is extremely simple,” Pullin said. Under their simplified model,”the black hole exists forever and doesn’t evolve. As a consequence I cannot tell you exactly what nature is going to do inside a black hole. It could be that the singularity gets replaced by a region that gets highly curved, but not infinitely curved. Or it could be that it just doesn’t make sense — you get a region which doesn’t behave like classical space-time. It would interact with particles in different ways than we normally think.”

Now that they’ve achieved this step, the researchers hope to advance their work by making the black holes in their model more dynamic and changeable.

“The black holes we studied were in empty space — there was no matter in them. They were pure space-time,” Pullin said.”We’re trying to add matter, because then it addsdynamics. We’re in the middle of that now.”

The study was published May 23 in the journal Physical Review Letters.

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