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FIRE IN THE SKY: Major Solar System Disturbance - Fireball Sightings In The THOUSANDS Across The United States Are Reported To The American Meteor Society!

Posted date: 7:19 PM / comment : 0 ,

SPACE - Reports of meteor sightings are coming into the American Meteor Society by the thousands. According to one of the latest reports posted at the American Meteor Society website, “Its been a busy week for the AMS as we are bombarded by fireball reports from all different parts of the country. The latest event took place over Alabama and Georgia last night September 28th 7:30 PM local time. Over 250 witnesses from Virginia, Maryland, Kentucky, Tennessee, North Carolina, Alabama and Georgia have reported the event so far. Below is a heat map of the witnesses who saw the event. Click the image below for the event detail page and witness reports.” [1]


Meteor Shower
(Image: nightsky.jpl.nasa.gov)


Exactly why these meteors are coming into the atmosphere at this time is unknown. NASA and NOAA have yet to publish any reports on this phenomenon, although they did confirm the September 10, 2013 meteor that streaked across the sky in Alabama in theguardian.com article ‘Meteor enters atmosphere over Alabama and disintegrates, says Nasa’. An excerpt from the article reads, “Officials at the Marshall Space Flight Center in Huntsville say a baseball-size fragment of a comet entered Earth’s atmosphere above Alabama at 8:18pm CDT Monday. Nasa officials say the meteor traveled at a speed of 76,000 mph. They say just three seconds after hitting the atmosphere, it disintegrated 25 miles above the central Alabama town of Woodstock, producing a flash of light. Nasa spokeswoman Janet Anderson says that because it penetrated so deep into Earth’s atmosphere, eyewitnesses heard sonic booms.” [2] 


 
WATCH: Meteor across Alabama - Sept. 9, 2013.


The thousands of sightings of meteors are located at the American Meteor Society Observation page, where you can also sign-up to be a registered user. Interestingly, there are reports of meteor sightings from 40 states, including Atlanta, GA, Alabama, South Carolina, North Carolina, Kentucky and Tennessee as of September 28, 2013. Register to make reports athttp://www.amsmeteors.org/

One explanation of the increase in sighting is mentioned on the American Meteor Society website in the article ‘Meteor Activity Outlook for September 28 – October 4, 2013’ which explains, “The September-October Lyncids (SOL) are only well seen on 3 nights centered on September 29th. Maximum occurs on the 30th when the radiant is located at 07:24 (111) +47. This position lies in western Lynx, 12 degrees north of the second magnitude star known as Castor (Alpha Geminorum). This area of the sky is best placed in the sky during the last hour before dawn, when it lies highest above the horizon in a dark sky. Rates at maximum are expected to be near one shower member per hour as seen from the northern hemisphere. These meteors can be seen from the tropical southern hemisphere but rates would be less than one per hour. With an entry velocity of 67 km/sec., most activity from this radiant would be of swift speed.” [5]

Earthsky.org posted an article by Deborah Byrd titled “U.S. sees another bright fireball on September 27’ which covers the meteor sightings in detail, which reads, “The American Meteor Society (AMS) has reported at least 373 reports of another bright fireball – a very bright meteor, likely a small chunk of natural incoming space debris – over the U.S. last night (September 27, 2013). These reports followed a similar event over approximately the same area the day before (September 26). The AMS called the coincidence of two bright fireballs, or bright meteors, spotted over approximately the same region on consecutive days “surprising.” Witnesses from Georgia, Illinois, Indiana, Kentucky, Maryland, North Carolina, New York, Ohio, Pennsylvania, Tennessee, Virginia, Wisconsin and West Virginia reported a bright light moving across the night sky on September 27 at around 11:33 p.m. local time, according to the AMS.” [6]

Sources:
[1] Another Massive Fireball Over Atlanta – amsmeteors.org
[2] Meteor enters atmosphere over Alabama and disintegrates, says NASA – theguardian.com
[3] American Meteor Society Observations – amsmeteors.org
[4] Meteor lights up early-morning sky in Midwest – chicagotribune.com
[5] Meteor Activity Outlook for September 28-October 4, 2013 – amsmeteors.org
[6] U.S. sees another bright fireball on September 27 – earthsky.org

Ball Lightning

Posted date: 10:30 AM / comment : 0 , , ,

Chinese scientists have recorded the rare phenomenon in nature for the first time

For centuries, people have reported seeing luminous, spherical orbs during storms — a phenomenon known as “ball lightning”. According to eyewitness reports they last for several seconds, moving through the air before eventually exploding.
But meteorologists have always regarded such reports with suspicion, as they’d never been able to observe the phenomenon themselves. Inconsistencies in public reports led those studying these cases starting to think of them like UFO sightings — merely hallucinations, perhaps caused by electromagnetic effects.
Now, however, following years of attempts to replicate ball lightning in the lab, Chinese researchers have finally recorded it in the field.
Discharging a high-voltage capacitor in a tank of water yields a ball-like discharge. // Sfusare, CC BY-SA 3.0
Jianyong Cen, Ping Yuan, and Simin Xue were usingspectrographs and video cameras to observe a thunderstorm near Qinghai in China’s desolate western provinces when they saw something they weren’t expecting.
After a bolt of lightning hit the ground, a glowing ball about five metres wide rose up and travelled about 15 metres, before disappearing about 1.6 seconds later.
Stunned, the researchers packed up their kit and headed back to their lab, where they discovered that the elements in the ball were the same as those in the local soil — silicon, iron and calcium. They published their results in the journal Physical Review Letters.
Their results lend credence to a theory first laid out in 1999 by John Abrahamson, a chemist at the University of Canterbury in New Zealand.
His theory goes that when lightning strikes the ground, it immediately stores energy in silicon nanoparticles in the soil. The force of the strike then ejects those particles into the air, where they’re oxidised and release that energy as heat and light, glowing briefly.
That doesn’t explain all the situations where ball lightning has been seen — like on aircraft flying high in the sky. But Abrahamson says that his findings fit the Chinese researchers’ results nicely. “Here’s an observation which has all the hallmarks of our theory,” he told New Scientist. “This is gold dust as far as confirmation goes.”

Milky Way Galaxy Has Four Spiral Arms, New Study Confirms

Posted date: 7:07 AM / comment : 0 , ,

A 12-year study published in the Monthly Notices of the Royal Astronomical Society has confirmed that our Milky Way Galaxy has four spiral arms, following years of debate that it has only two arms.
Galactic distribution of massive young stars and compact and ultra-compact H II regions with luminosities greater than 10^4 times that of the Sun. The map shows the positions of the complexes and individual sources as red and blue circles, respectively. The sizes of the markers give an indication of their luminosity, as depicted in the upper-right corner. The position of the Sun is shown by the small circle above the Galactic Centre. The two solid lines enclose the Galactic Center region that was excluded from survey due to problems with source confusion and distance determination. The smaller of the two dot–dashed circles represents the locus of tangent points, while the larger circle shows the radius of the solar circle. Image credit: Urquhart JS et al / Robert Hurt, the Spitzer Science Center / Robert Benjamin.
Galactic distribution of massive young stars and compact and ultra-compact H II regions with luminosities greater than 10^4 times that of the Sun. The map shows the positions of the complexes and individual sources as red and blue circles, respectively. The sizes of the markers give an indication of their luminosity, as depicted in the upper-right corner. The position of the Sun is shown by the small circle above the Galactic Centre. The two solid lines enclose the Galactic Center region that was excluded from survey due to problems with source confusion and distance determination. The smaller of the two dot–dashed circles represents the locus of tangent points, while the larger circle shows the radius of the solar circle. Image credit: Urquhart JS et al / Robert Hurt, the Spitzer Science Center / Robert Benjamin.
“The Milky Way is our galactic home and studying its structure gives us a unique opportunity to understand how a very typical spiral galaxy works in terms of where stars are born and why,” said co-author Prof Melvin Hoare from the University of Leeds.
In the 50s, astronomers used radio telescopes to map the Milky Way. Their observations focused on clouds of gas in the Galaxy in which new stars are born, revealing four major spiral arms.
In 2008, scientists using NASA’s Spitzer Space Telescope scoured our Galaxy for infrared light emitted by stars. They revealed about 110 million stars, but only evidence of two spiral arms.
The astronomers behind the new study used several radio telescopes to individually observe about 1,650 massive stars in the Galaxy. The distances and luminosities of these stars were calculated, revealing a distribution across four spiral arms.
“It isn’t a case of our results being right and those from Spitzer’s data being wrong – both surveys were looking for different things. Spitzer only sees much cooler, lower mass stars – stars like our Sun – which are much more numerous than the massive stars that we were targeting,” Prof Hoare said.
Massive stars are much less common than their lower mass counterparts because they only live for a short time – about 10 million years. The shorter lifetimes of massive stars means that they are only found in the arms in which they formed, which could explain the discrepancy in the number of galactic arms that different research teams have claimed.
“Lower mass stars live much longer than massive stars and rotate around our Galaxy many times, spreading out in the disc. The gravitational pull in the two stellar arms that Spitzer revealed is enough to pile up the majority of stars in those arms, but not in the other two. However, the gas is compressed enough in all four arms to lead to massive star formation,” Prof Hoare said.
“It’s exciting that we are able to use the distribution of young massive stars to probe the structure of the Milky Way and match the most intense region of star formation with a model with four spiral arms,” said lead author Dr James Urquhart of the Max Planck Institute for Radio Astronomy in Bonn, Germany.

Urquhart JS et al. The RMS survey: galactic distribution of massive star formation. MNRAS 437 (2): 1791-1807; doi: 10.1093/mnras/stt2006

NASA: Asteroid coming close in 2032 no concern

Posted date: 6:19 PM / comment : 0 ,


This is an artist impression obtained from The University of Warwick and The University of Cambridge shows a rocky and water-rich asteroid being torn apart by the strong gravity of the white dwarf star GD 61. AFP PHOTO / Image copyright Mark A. Garlick, space-art.co.uk, The University of Warwick and The University of Cambridge


WASHINGTON: NASA says a big asteroid that whizzed by Earth last month unnoticed is probably nothing to worry about when it returns much closer in 19 years.
NASA Near-Earth Object program manager Donald Yeomans said there is a 1 in 48,000 chance that the 1,300-foot (400-meter) asteroid will hit Earth when it returns on Aug. 26, 2032.
The asteroid called 2013 TV135 was discovered Oct. 8, nearly a month after it came within 4.2 million miles (6.7 million kilometers) of Earth. Yeomans said as astronomers observe and track it better, they will likely calculate that it has no chance of hitting Earth.
Although big, the asteroid is considerably smaller than the type that caused the dinosaur extinction.
NASA posted a "reality check" about the asteroid in response to some media reports.

Pulverized Asteroid around Distant Star Was Full of Water

Posted date: 6:35 PM / comment : 0 , , ,



It is the first discovery of a rocky and watery body beyond our solar system. The rubble appears to be the remains of a destroyed planetary system around the white dwarf GD 61, 170 light years away. The debris may give insights into how planets get their oceans, as scientists theorise that the oceans on Earth arrived via comet and asteroid impacts. 

The researchers used the Hubble Space Telescope’s Cosmic Origins Spectrograph to observe GD 61 and split its light into constituent colors, revealing the chemicals it contains. They found magnesium, iron, silicon and other heavy elements, which wouldn’t exist naturally on the surface of a white dwarf, suggesting that they fell onto the star from an orbiting object. The researchers also found a huge excess of oxygen—an amount, they say, that indicates the asteroid polluting the star’s surface was originally composed of 26 percent water. That’s pretty wet—Earth, by contrast, is only 0.02 percent water. “This work marks the first detection of water-rich rocks in exoasteroids, and is an important step in developing a comprehensive picture of exoplanetary systems,” says Kevin France of the University of Colorado at Boulder, who wasn’t involved in the research.
The find could be significant, because theorists think Earth, having formed too close to the sun for water to survive, got its oceans from just such large, wet asteroids that impacted it long ago. “We’ve got the same kind of object which probably delivered Earth’s oceans, and we found this around another star,” says research leader Jay Farihi at the University of Cambridge in England. The discovery, he says, is a step in the quest to find habitable worlds, and maybe even life, beyond Earth. “This goes beyond planets in the habitable zone. We have some actual chemistry that tells you the ingredients for habitable planets were there.”
Some experts aren’t convinced that the oxygen found on the surface of the white dwarf is a clear sign that water existed on an orbiting asteroid, however. “The link of the pollution of a white dwarf to the inventory of water in an earlier planetary system is a very interesting scientific question still under investigation,” says exoplanet researcher Lisa Kaltenegger of Harvard University and the Max Planck Institute for Astronomy in Germany, who was not involved in the research. Claire Moutou, another exoplanet specialist at the Laboratory of Astrophysicsof Marseille in France, agreed. “I find the analysis/conclusions of the paper reasonable, as far as the amount of oxygen available to lie in H2O molecules is concerned. The interpretation of the origin of this water content is more speculative.”
The scientists behind the project, which is detailed in the October 11 issue of Science, say they took pains to verify that the chemicals they see really do prove the destroyed asteroid had water. They observed the star GD 61 in many wavelengths through many telescopes, including NASA’s Spitzer Space Telescope and two instruments on the W. M. Keck Observatory in Hawaii, along with Hubble. “The authors seem to have done a careful job of cataloguing the elements and searching for reasons to explain away the oxygen excess,” says debris disk expert John Debes of the Space Telescope Science Institute in Baltimore. “The detection of hydrogen in addition to the oxygen is a really convincing signature of water.” The finding sheds light on how planets form and evolve, adds Brice-Olivier Demory, an exoplanet researcher at the Massachusetts Institute of Technology who also was not involved in the research. “This is a startling result strengthening the fact that water can be found in a very diverse range of environments.”

Star Found Shooting Water "Bullets". Stellar sprinklers may help irrigate cosmos, study suggests.

Posted date: 5:07 PM / comment : 0 , ,


An illustration of a protostar.
A star is born: Swirling gas and dust fall inward, spurring polar jets, shown in blue in this illustration.
Illustration courtesy NASA/Caltech 
Andrew Fazekas
Seven hundred and fifty light-years from Earth, a young, sunlike star has been found with jets that blast epic quantities of water into interstellar space, shooting out droplets that move faster than a speeding bullet.
The discovery suggests that protostars may be seeding the universe with water. These stellar embryos shoot jets of material from their north and south poles as their growth is fed by infalling dust that circles the bodies in vast disks.
"If we picture these jets as giant hoses and the water droplets as bullets, the amount shooting out equals a hundred million times the water flowing through the Amazon River every second," said Lars Kristensen, a postdoctoral astronomer at Leiden University in the Netherlands.
"We are talking about velocities reaching 200,000 kilometers [124,000 miles] per hour, which is about 80 times faster than bullets flying out of a machine gun," said Kristensen, lead author of the new study detailing the discovery, which has been accepted for publication in the journal Astronomy & Astrophysics.
Water Vanishes, Only to Reappear
Located in the northern constellation Perseus, the protostar is no more than a hundred thousand years old and remains swaddled in a large cloud—gas and dust from which the star was born.
Using an infrared instrument on the European Space Agency's Herschel Space Observatory, researchers were able to peer through the cloud and detect telltale light signatures of hydrogen and oxygen atoms—the building blocks of water—moving on and around the star.
After tracing the paths of these atoms, the team concluded that water forms on the star, where temperatures are a few thousand degrees Celsius. But once the droplets enter the outward-spewing jets of gas, 180,000-degree-Fahrenheit (100,000-degree-Celsius) temperatures blast the water back into gaseous form.
Once the hot gases hit the much cooler surrounding material—at about 5,000 times the distance from the sun to Earth—they decelerate, creating a shock front where the gases cool down rapidly, condense, and reform as water, Kristensen said.
Stellar Sprinkler Nourishes Galactic "Garden"
What's really exciting about the discovery is that it appears to be a stellar rite of passage, the researchers say, which may shed new light on the earliest stages of our own sun's life—and how water fits into that picture.
"We are only now beginning to understand that sunlike stars probably all undergo a very energetic phase when they are young," Kristensen said. "It's at this point in their lives when they spew out a lot of high-velocity material—part of which we now know is water."
Like a celestial sprinkler system, the star may be enriching the interstellar medium—thin gases that float in the voids between stars. And because the hydrogen and oxygen in water are key components of the dusty disks in which stars form, such protostar sprinklers may be encouraging the growth of further stars, the study says.
The water-jet phenomenon seen in Perseus is "probably a short-lived phase all protostars go through," Kristensen said.
"But if we have enough of these sprinklers going off throughout the galaxy—this starts to become interesting on many levels."

Luna 15 and Apollo 11: A Near-Miss on the Moon?

Posted date: 5:41 PM / comment : 0 ,

It was mid-day on July 21, 1969. Engineers at Mission Control in Houston were preparing for Apollo 11's departure from the moon. Neil Armstrong and Buzz Aldrin's excursion onto the moon's surface was over, and they were stowing equipment in preparation for liftoff early in the afternoon. Meanwhile, a Soviet probe, Luna 15, crash landed on the moon!

 Luna 15 was launched three days before the Apollo 11 lift-off. Its aim was to land on the lunar surface, collect rock samples, and return to Earth. If all went well, it could have arrived back on Earth the same day the astronauts came home: a small victory for the Soviets (whose Luna 2 spacecraft was the first human-made object to reach the moon, in 1959). But after several dozen orbits of the moon, the probe's landing didn't go as planned. It stopped transmitting four minutes into its descent, and crashed at Mare Crisium.
I was curious about how far the Luna crash was from the Apollo 11 Lunar Module. Mare Crisium is the "sea" directly north of Mare Tranquilltatis, site of Apollo 11's landing. According to Yahoo Answers (maybe not the most reliable source?), the two crafts were a little over 740 miles apart. 

Was the Apollo 11 mission ever in danger of a collision with Luna 15? Were the Soviets aiming to crash their probe into the Lunar Module? We know now that the answer to both questions was "no." But apparently back in 1969 NASA officials had some concerns. Astronaut Frank Borman put a call into one of the leaders of the Soviet space program, Dr. Mstislav Keldysh, asking him to confirm that the probe posed no threat to Apollo 11's mission. In what some describe as the very first instance of U.S.-Soviet cooperation in the space race, the Soviets released Luna 15's flight plan to NASA officials, allaying fears that it was on a collision course with the Lunar Module or the Command Module. 

During their mission, Armstrong, Aldrin, and Michael Collins were kept apprised of Luna 15's status. Apparently there were others tracking the craft as well. Astronomers at the University of Manchester Jodrell Bank radio telescope eavesdropped on Luna 15's final minutes. Their recordings were released in 2009; you can listen to a British scientist narrate the craft's crash here.

So the space race effectively ended that day. Americans were first to walk on the moon, hours before an unmanned Soviet landing failed. But, in the process, the U.S. and the U.S.S.R. first cooperated in space!

  1.  "Russian spacecraft landed on Moon hours before Americans". telegraph.co.uk. 4 July 2009. Retrieved 2009-11-15.
  2. Recording tracks Russia's Moon gatecrash attempt

Of white blood cells and stars

Posted date: 10:32 AM / comment : 1

"If you brought the Sun down to the size of a white blood cell (7 micrometres), and then brought everything else down to scale, our galaxy, the Milky Way, would be the size of the continental U.S.A."

Source: Tredid on reddit
Picture credit: Michael Richmond
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