A Near-earth Object, Asteroid 1998 QE2, Is Now Hurtling Towards Earth


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Myself . By T.V. Antony Raj
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Asteroid 1998 QE2 - 1

A near-earth object labeled Asteroid 1998 QE2, is now hurtling towards earth.

The asteroid about 1.7 miles (2.7 kilometers) or nine Queen Elizabeth 2 ship-lengths in size in length has the physical mass to potentially knockout life on Earth. However, we are safe as it is just flying by.

The orbit of asteroid 1998 QE2

On May 31, 2013, at 20:59 UTC (1:59 p.m. Pacific / 4:59 p.m. Eastern) this asteroid will pass within 3.6 million miles (5.8 million km) of Earth – about 15 times the distance to the Moon. While this may seem a great distance for the layman, in astronomical terms it is a mere stone’s throw away. This is the closest approach the asteroid will make to Earth for at least the next two centuries.

The Massachusetts Institute of Technology Lincoln Near Earth Asteroid Research (LINEAR) program near Socorro, New Mexico, discovered this asteroid on August 19, 1998. It is officially known as Asteroid 1998 QE2. It is not named in honor of Queen Elizabeth II, or after that 12-decked, transatlantic-crossing flagship for the Cunard Line. The name was assigned by the NASA-supported Minor Planet Center in Cambridge, Massachusetts, USA. This institute assigns each newly discovered asteroid a provisional designation starting with the year of first detection, along with an alphanumeric code showing the half-month it was discovered, and the sequence within that half-month.

Though this asteroid is not of much interest to those astronomers and scientists on the lookout for hazardous asteroids, it is of interest to those who dabble in radar astronomy and have a 230-foot (70-meter) or larger radar telescopes at their disposal.

Radar astronomer Lance Benner, the principal investigator for the Goldstone radar observations from NASA’s Jet Propulsion Laboratory in Pasadena, California said: “Asteroid 1998 QE2 will be an outstanding radar imaging target at Goldstone and Arecibo and we expect to obtain a series of high-resolution images that could reveal a wealth of surface features … Whenever an asteroid approaches this closely, it provides an important scientific opportunity to study it in detail to understand its size, shape, rotation, surface features, and what they can tell us about its origin. We will also use new radar measurements of the asteroid’s distance and velocity to improve our calculation of its orbit and compute its motion farther into the future than we could otherwise.”

Asteroid 1998 QE2

Asteroids come in various sizes and shapes: dog bones, bowling pins, spheroids, diamonds, muffins, potatoes, etc. Between May 30 and June 9, radar astronomers using NASA’s 230-foot-wide (70 meter) Deep Space Network antenna at Goldstone, California, and the Arecibo Observatory in Puerto Rico, are planning an extensive campaign of observations. The two telescopes with complementary imaging capabilities will enable astronomers to study 1998 QE2 and what it looks like during its brief flyby.

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Massive Solar Eruption Could Cause Magnetic Storm Here on Earth


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Deborah Netburn

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By Deborah Netburn

Posted on April 11, 2013 in Los Angeles Times

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Massive solar eruption April 11, 2013

Massive solar eruption on April 11, 2013

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Early Thursday morning, solar observers watched as a dark spot on the sun erupted with an enormous flash of light, causing the biggest solar flare of 2013.

Solar flares themselves don’t last long, but this one was powerful enough to cause a bubble of solar material called a CME (coronal mass ejection) to come bursting off the sun.

Up to billions of tons of that solar material is now hurtling through space at the mind-bending speed of more than 600 miles per second, and it is heading directly toward Earth.

The CME will slow down a bit as it approaches our planet, and scientists expect it will reach the Earth’s atmosphere late Friday night or early Saturday, but computer models can be off by up to seven hours either way, said NASA scientist Alex Young.

While a mass of solar material zooming toward Earth sounds kind of frightening, there’s not much to worry about. CMEs can occasionally affect the electronic systems of satellites or the power grid here on the ground, but our atmosphere will protect us from any harmful radiation associated with the initial flare or the CME.

Plus, there’s a major upside to these Earth-bound CMEs for sky watchers. When a CME interacts with the Earth’s magnetosphere, it can cause geomagnetic storms and enhanced auroras that could be visible as far south as Michigan and New York.

Here in Southern California, we still won’t be able to see them, but we’ll look online for spectacular photos and videos of glowing green skies on the days after the CME hits.

Although Thursday morning’s solar flare is the strongest to be recorded in 2013, NASA has classified it as a mid-level flare, and the agency notes that it was 10 times less powerful than the strongest flares, which are labeled X-class flares.

M-class flares are the weakest flares that can still cause effects on Earth. Thursday’s solar flare was responsible for a brief radio blackout, NASA reported.

The sun is currently nearing the peak of its 11-year solar flare cycle, or what is known as solar max. At the peak of the cycle, it is normal for there to be several solar flares a day.

Young said we should expect more and larger solar flares toward the end of the year and the beginning of next year.

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The Meteorite Explosion that Shook Chelyabinsk, Russia on February 15, 2013


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Myself By T.V. Antony Raj

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Russian Meteor

A meteor seen flying over Russia on Feb. 15 at 3:20: 26 UTC impacted Chelyabinsk.

A meteor entered the Earth’s atmosphere and disintegrated in the skies over Chelyabinsk, Russia, at 7:20:26 PM PST, or 10:20:26 PM EST on February 14 (3:20:26 UTC on February 15).

At a news conference on Friday, NASA scientists said the object was a “tiny asteroid”. The trajectory of this meteor differed appreciably from the trajectory of the asteroid 2012 DA14, which hours later made its flyby of Earth, making both objects completely unrelated.

The Russian Emergency Ministry described it as a shower of meteorite debris. However, some unconfirmed reports suggested that Russian air defenses shot down a meteorite. NASA asteroid expert Don Yeomans, head of the agency’s Near-Earth Object Program Office, said that the object which exploded was most likely an exploding fireball known as a bolide.

According to the preliminary information that appeared in the media unidentified flying objects exploded over several cities in Russia, and the object at Chelyabinsk measured 49 feet (15 meters) across, weighing 7,000 tons and released 30 kilotons of energy when it exploded, and the blast waves blew out window glass of buildings in Chelyabinsk, sending dozens to hospitals, disrupted mobile services, and reportedly injured more than 1,000 people. Many dashboard videos appeared online, showing huge fireballs flying over buildings and exploding with a strong blast. Some walls of the Chelyabinsk Zinc Factory that produced 160,000 metric tons of refined zinc and alloys last year collapsed with extensive damage to the plant.

Now NASA says information provided by a worldwide network of sensors has allowed scientists to revise their estimates for the size of the object before entering Earth’s atmosphere to 55 feet (17 meters), weighing about 10,000 tons. Bill Cooke, head of the Meteoroid Environment Office at NASA’s Marshall Space Flight Center in Huntsville, Alabama said the energy released during the explosion amounted to 500 kilotons equal to that of an exploding modern nuclear bomb.

Fresh data collected from five more infrasound stations located around the world helped to generate these new estimates. The first infra-sound recording of the event took place in Alaska – over 6,500 kilometers away from Chelyabinsk. Calculations performed by Peter Brown at the University of Western Ontario, Canada, using infrasound data show the time taken by the object from entering the atmosphere to its disintegration in the air took 32.5 seconds.

Paul Chodas of NASA’s Near-Earth Object Program Office at the Jet Propulsion Laboratory in Pasadena, California said, “We would expect an event of this magnitude to occur once every 100 years on average “

The present Russia meteor is the largest reported since 1908, when a meteor hit Tunguska, Siberia.

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A Near-Earth Object, Asteroid 2012 DA14 Now Hurtling Towards Earth


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Myself By T.V. Antony Raj
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Comets and asteroids that enter the Earth’s neighborhood nudged by the gravitational attraction of nearby planets are known as near-Earth Objects (NEOs).

One such near-Earth asteroid named 4179 Toutatis formerly known as 1989 AC was discovered by Christian Pollas on January 4, 1989, at Caussols, France. On
December 12, 2012, this asteroid with a shape of a “malformed potato” tumbled through space like a fumbled football, within 4.3 million miles from Earth.

UPCOMING CLOSE APPROACHES TO EARTH - 2

Another near-Earth asteroid discovered on February 23, 2012, by the OAM Observatory, La Sagra in Spain with an estimated diameter of about 45 meters (about half the size of a football field) weighing about 130,000 metric tons mass probably made of stone in contrast to metal or ice is now hurtling towards the earth.

Diagram of 2012 DA14 passing the Earth on 15 February 2013

Diagram of 2012 DA14 passing the Earth on 15 February 2013

On February 15, 2013, this asteroid labeled 2012 DA14 will pass within about 3.5 Earth radii of the Earth’s surface inside the geosynchronous weather and communication satellites ring, approximately 35,800 kilometers above the equator.

Even though asteroids like 2012 DA14 fly past Earth almost every 40 years they impact with our planet only every 1200 years or so. Don Yeomans, Paul Chodas, and Jon Giorgini of NASA/JPL Near-Earth Object Program Office after predicting the asteroid’s path have declared that according to their observations, there is no chance that the asteroid might be on a collision course with the Earth, and it will safely fly past Earth’s outer ring of satellites on February 15.

“Since regular sky surveys began in the 1990s, we’ve never seen an object this big gets so close to Earth,” Don Yeomans said.

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December 21, 2012: Winter Solstice in the Northern Hemisphere or Is It Doomsday 2012?


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Myself . By T.V. Antony Raj

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solstices

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The astronomical event known as the solstice occurs when the Sun reaches its highest or lowest excursion point relative to the celestial equator on the celestial sphere. This event occurs twice a year.

On the day of the solstice, at local solar noon, the Sun appears to have reached its highest or lowest annual altitude in the sky above the horizon.

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UT date and time of equinoxes and solstices on the earth

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For any place other than the tropics the solstice day in summer is the longest day of the year, and the solstice day in winter is the shortest day of the year.

During the winter solstice in the Northern Hemisphere, also known as the Southern solstice that occurs on December 21st to 22nd, the Sun at noon would appear at its lowest altitude above the horizon, namely, at its southernmost point in the sky. On the other hand, in the Southern Hemisphere, the winter solstice also known as the Northern solstice occurs on June 20th to 21st each year.  On this day, the Sun appears at its northernmost point in the sky.

The axis of rotation of the earth directed towards the same point in the heavens is the result of its axial tilt and the gyroscopic influences of its daily rotation. As the Earth orbits around the Sun, the polar hemisphere facing the Sun encountering summer would after six months face away from the Sun to  endure the winter.

The solstices last only a moment in time. This year, winter solstice would occur today, December 21, 2012 at 11:12 AM UTC (6:12 AM EST; 4:42 PM IST).

Worldwide, interpretation of the winter solstice varies from culture to culture. However, all recognize the rebirth of the Earth that involves religious festivals, rituals, and other celebrations. The following lists a few observance believed to be directly linked to the winter solstice.

mayan-calendar-300x291

This brings us to the Doomsday Prophecy attributed by some to the Mayan Calendar. Though the Mayans never predicted that the world would end today, December 21, 2012, some doomsday soothsayers have been touting all these days that around 80 percent of the world population would be wiped out on this fateful day. Many who believe these scare mongers have left their homes; they have traveled to places where they think their chances of survival will be better.

Ten hours ago, I read an article titled “Global doomsday hot spots draw believers, revelers” by Vanessa Gera where she describes some of the world’s key doomsday destinations and other places marked by fear and fascination.

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Day Before Yesterday NASA Released Video: “Why the World Didn’t End Yesterday”


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Myself . By T.V. Antony Raj

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NASA is so sure the world won’t come to an end on December 21, 2012, that they already released day before yesterday a “Didn’t We Say So!” video titled “ScienceCasts: Why the World Didn’t End Yesterday” on December 11th, itself.

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3MIN News December 12, 2012: Geminid Meteor Showers


by Suspicious0bservers

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Click on the image to see the video.

.3MIN News December 12, 2012 - Geminid Meteor Showers

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Asteroid 2012 DA14 Will Pass the Earth on February 15, 2013


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Myself By T.V. Antony Raj

.UPCOMING CLOSE APPROACHES TO EARTH

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On February 23, 2012, the OAM Observatory, La Sagra in Spain discovered a near-earth asteroid with an estimated diameter of about 45 meters and about 130,000 metric tons mass hurtling towards the earth. On February 15th, 2013, this asteroid named 2012 DA14 will pass within about 3.5 Earth radii of the Earth’s surface inside the geosynchronous satellite ring, located about 35,800 kilometers above the equator. According to Paul Chodas, Jon Giorgini and Don Yeomans of NASA/JPL Near-Earth Object Program Office the asteroid will not impact the Earth on February 15, 2013.

Diagram of 2012 DA14 passing the Earth on 15 February 2013

Diagram of 2012 DA14 passing the Earth on 15 February 2013. – Author: NASA/JPL Near-Earth Object Program Office.

As per calculations, on February 15, 2013, the distance between the asteroid and the Earth will be 0.09 Lunar Distance (35,000 kilometers; 21,000 miles) and travel rapidly from the southern evening sky into the northern morning sky. Its closest Earth approach to Earth would occur at 19:26 UTC achieving magnitude of less than seven; somewhat fainter than naked-eye visibility. Four minutes later 2012 DA14 after passing into the Earth’s shadow for 18 minutes it will reappear from the eclipse, travel swiftly into the northern morning sky and would disappear.

Note: LD = Lunar Distance = ~384,000 kilometers (238,900 miles) .

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“Mysterious bright flash in sky reported across Texas” by Marjorie Owens


By Marjorie Owens 

December 7, 2012

Bright lights over Texas

KHOU 11 News viewer Mary Bush took this photo about two minutes after the flash.

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DALLAS – From McKinney to the White Rock Lake area and all the way south to Houston, a bright flash reported in the sky Friday morning captured the attention of many across the Lone Star State.

While early reports indicated it was likely a meteor, the National Weather Service in Houston reported Friday afternoon that it may have been debris from the Russian Satellite Cosmos 2251 as it reentered the atmosphere.

In 2009, the Cosmos 2251 satellite, which was not in working condition at the time, collided with Iridium 33, a United States communication satellite, in 2009 as they orbited Earth over Siberia.

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Meanwhile, Bill Cooke, who heads the Meteoroid Environment Office for NASA, told KRLD that the object was actually a meteor, and was likely the size of a basketball.

As researchers continue to investigate the source of the flash, reports of sightings continue to grow across Texas.

One McKinney woman reported seeing what appeared to be a comet streaking across the sky in a bright flash around 6:42 a.m. near Stonebridge Shopping Center.

Justin Wagoner, who lives in the White Rock Lake area, said he saw a green trail and heard a large “sonic boom” around the same time. Others reported seeing white and orange colors. The sight only lasted a few seconds before vanishing in the sky.

According to Dr. James Roberts, a University of North Texas astronomer who talked to WBAP early Friday morning,  the mysterious object in the sky was likely a burned up meteor. A KHOU meteorologist in Houston said it may have been part of the Geminids meteor shower, which takes place in December. The meteorites often appear to be slow moving and are usually best seen at its peak on December 13 and 14.

However, Mike Hankey, the operations manager with the American Meteor Society, said later in the morning he believed the meteor was likely a fireball, a meteor brighter than Venus, and not a part of the Geminid shower.

“For those not familiar with meteors and fireballs, a fireball is a meteor that is larger than normal,” read a report on the American Meteor Society’s online site. “Most meteors are only the size of small pebbles. A meteor the size of a softball can produce light equivalent to the full moon for a short instant. The reason for this is the extreme velocity at which these objects strike the atmosphere.”

Seeing a fireball is something not everyone gets a chance to do in their lifetime, according to Hankey.

“While fireballs are actually pretty common across the globe, they happen every night, to actually see one in your area is very rare,” he said. “If you see one once in your life, you are very lucky.”

The loud boom heard by some could be explained by what happens when a large fireball breaks apart, Hankey went on to explain.

Bolide

Bolide (Photo credit: Wikipedia)

“Really big fireballs that break apart and cause a sonic boom are called ‘bolides,” Hankey said. “Bolides usually drop meteorites to the ground. It is still not known if this was a bolide or just a fireball.”

Since some reported hearing a loud noise, Hankey said that leaves open the possibility that the meteor may have been a bolide.

“Sonic boom means there are meteorites on the ground,” he went on to explain. “Why? Because the meteor would have had to penetrate the atmosphere deep enough to make a sonic boom, When it gets that deep, there’s practically no chance of it vaporizing in the air. Most meteors vaporize in the upper atmosphere, but when they make it low enough to cause a sonic boom, they are generally big enough to leave meteorites.”

While Hankey said the meteor was likely not associated with the Geminids as they are usually dimmer and move at a faster pace, he said the organization is looking further into the case to determine the exact type of meteor that was sighted.

METEOR TERMINOLOGY AS DEFINED BY AMS:

  • Meteoroid: Object floating in space
  • Meteor: Light effect caused by meteoroid hitting the earth
  • Fireball: Meteor brighter than Venus
  • Bolide: Fireball that explodes / fragments into many parts (and usually leaves meteorites)
  • Meteorite: A space rock / meteoroid that survives entry into the atmosphere and hits the ground

Source: WFAA

KHOU contributed to this report

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Greenland ice sheet melted at unprecedented rate during July 2012


 US environment correspondent
Tuesday 24 July 2012 17.48 EDT

Scientists at Nasa admitted they thought satellite readings were a mistake after images showed 97% surface melt over four days

The Greenland ice sheet on July 8, left, and four days later on the right. In the image, the areas classified as ‘probable melt’ (light pink) correspond to those sites where at least one satellite detected surface melting. The areas classified as ‘melt’ (dark pink) correspond to sites where two or three satellites detected surface melting. Photograph: Nasa

The Greenland ice sheet melted at a faster rate this month than at any other time in recorded history, with virtually the entire ice sheet showing signs of thaw.

The rapid melting over just four days was captured by three satellites. It has stunned and alarmed scientists, and deepened fears about the pace and future consequences of climate change.

In a statement posted on Nasa’s website on Tuesday, scientists admitted the satellite data was so striking they thought at first there had to be a mistake.

“This was so extraordinary that at first I questioned the result: was this real or was it due to a data error?” Son Nghiem of Nasa’s Jet Propulsion Laboratory in Pasadena said in the release.

He consulted with several colleagues, who confirmed his findings. Dorothy Hall, who studies the surface temperature of Greenland at Nasa’s space flight centre in Greenbelt, Maryland, confirmed that the area experienced unusually high temperatures in mid-July, and that there was widespread melting over the surface of the ice sheet.

Climatologists Thomas Mote, at the University of Georgia, and Marco Tedesco, of the City University of New York, also confirmed the melt recorded by the satellites.

However, scientists were still coming to grips with the shocking images on Tuesday. “I think it’s fair to say that this is unprecedented,” Jay Zwally, a glaciologist at Nasa’s Goddard Space Flight Center, told the Guardian.

The set of images released by Nasa on Tuesday show a rapid thaw between 8 July and 12 July. Within that four-day period, measurements from three satellites showed a swift expansion of the area of melting ice, from about 40% of the ice sheet surface to 97%.

Scientists attributed the sudden melt to a heat dome, or a burst of unusually warm air, which hovered over Greenland from 8 July until 16 July.

Greenland had returned to more typical summer conditions by 21 or 22 July, Mote told the Guardian.

But he said the event, while exceptional, should be viewed alongside other compelling evidence of climate change, including on the ground in Greenland.

“What we are seeing at the highest elevations may be a sort of sign of what is going on across the ice sheet,” he said. “At lower elevations on the ice sheet, we are seeing earlier melting, melting later in the season, and more frequent melting over the last 30 years and that is consistent of what you would expect with a warming climate.”

Zwally, who has made almost yearly trips to the Greenland ice sheet for more than three decades, said he had never seen such a rapid melt.

About half of Greenland’s surface ice sheet melts during a typical summer, but Zwally said he and other scientists had been recording an acceleration of that melting process over the last few decades. This year his team had to rebuild their camp, at Swiss Station, when the snow and ice supports melted.

He said he had never seen such a rapid melt over his three decades of nearly yearly trips to the Greenland ice sheet. He was most surprised to see indications in the images of melting even around the area of Summit Station, which is about two miles above sea level.

It was the second unusual event in Greenland in a matter of days, after an iceberg the size of Manhattan broke off from the Petermann glacier. But the rapid melt was viewed as more serious.

“If you look at the 8 July image that might be the maximum extent of warming you would see in the summer,” Zwally noted. “There have been periods when melting might have occurred at higher elevations briefly – maybe for a day or so – but to have it cover the whole of Greenland like this is unknown, certainly in the time of satellite records.”

Jason Box, a glaciologist at Ohio State University who returned on Tuesday from a research trip to Greenland, had been predicting a big melt year for 2012, because of earlier melt and a decline in summer snow flurries.

He said the heat dome was not necessarily a one-off. “This is now the seventh summer in a row with this pattern of warm air being lifted up onto the ice sheet on the summer months,” he said. “What is surprising is just how persistent this circulation anomaly is. Here it is back again for the seventh year in a row in the summer bringing hot, warm
air onto the ice sheet.”

He also said surfaces at higher elevation, now re-frozen, could be more prone to future melting, because of changes in the structure of the snow crystals. Box expected melting to continue at lower elevations.

About half of Greenland’s surface ice sheet melts during a typical summer, but Zwally said he and other scientists had been recording an acceleration of that melting process over the past few decades. This year his team had to rebuild their camp, at Swiss Station, when the snow and ice supports melted.

Lora Koenig, another Goddard glaciologist, told Nasa similar rapid melting occurs about every 150 years. But she warned there were wide-ranging potential implications from this year’s thaw.

“If we continue to observe melting events like this in upcoming years, it will be worrisome.” she told Nasa.

The most immediate consequences are sea level rise and a further warming of the Arctic. In the centre of Greenland, the ice remains up to 3,000 metres deep. On the edges, however, the ice is much, much thinner and has been melting into the sea.

The melting ice sheet is a significant factor in sea level rise. Scientists attribute about one-fifth of the annual sea level rise, which is about 3mm every year, to the melting of the Greenland ice sheet.

In this instance of this month’s extreme melting, Mote said there was evidence of a heat dome over Greenland: or an unusually strong ridge of warm air.

The dome is believed to have moved over Greenland on 8 July, lingering until 16 July.

Source: guardian.co.uk

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