If an asteroid hits earth it could very well be the end of days. We will not have Bruce Willis ready to give his life to save humanity and the human race may not recover. Doom and gloom? If an asteroid attack is keeping you up at night, you should know that the earth has been in the trajectory of asteroids, meteors and other space debris for thousands of years. Actually Factually
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Asteroids were formed when the space between Jupiter and Mars did not allow the formation of any planetary bodies. The objects in the space broke and fragmented giving rise to asteroids which can have a diameter of over 500 miles or as small as 20 feet. Asteroids travel around the sun in an elliptical orbit and due to their irregular shape can bounce off course, tumble and change orbit. Changing orbit sometimes means that an asteroid can encounter other planets. One of those is our home planet.
Historically we have little to go on when it comes to asteroid near misses in history. The Comet of 1491 came dangerously close, possibly less than four times the distance to the moon. In 1972, a comet bounced off the surface of the atmosphere streaking through the sky as a fireball over Utah. Only 14 meters in diameter, this near miss could have delivered an impact about half the strength of the atomic bomb that hit Hiroshima. Comet Hyakutake passed very close in 1996 and was discovered only two months before it started its earth approach. Close Encounters Of the Earth Ending Kind
NASA recorded the closest near miss of an asteroid in February of 2011. A small asteroid barely 1 metre in diameter passing as close as 5480 km from earth. That’s close, real close. Close enough to get people worried. Asteroid 2011CQ1 may have been small, but it was very definitely in our back yard and climbing up the front stairs. The scary part is that the asteroid, which had left its normal trajectory and had been pulled so close to the earth by the gravitational force, was only discovered 14 hours before it passed. Close, is of course a relative term when you’re talking about distances in space.
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Asteroid 2011MD, credit: Jaicoa
2011MD passed within 11 000 miles of our home and gave off a light so bright it could be seen with a small telescope. 32 times closer than the moon is considered a little close for comfort. The threat of an asteroid collision may not be imminent but astronomers and scientists are not able to predict what happens when an asteroid is pulled into our orbit and how it may behave due to its irregular shape.
2005YU5 came into the moons orbit on November 8 2011, giving scientists a rare chance to capture footage of its orbit. 2005YU55 is no stranger to us, and has been orbiting for thousands of years. This close though and who knows what happens.
Large asteroids have the ability to wipe out all life on earth if there is impact. We’re talking about asteroids the size of apartment buildings, houses and city blocks here. Asteroids That Keep Coming Back
Apophis is a 25 million ton asteroid that keeps threatening our skies. Having several near misses, this large celestial body seems to be getting closer and closer. Discovered in 2004, you can track the travels of Apophis (2004MN4) on several websites around the world. The closest pass of Apophis is estimated for 2029. Just around the corner really.
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Trajectory of Apophis in 2029, source: Wikipedia
The threat of an asteroid impact is measured on the Torino Scale. Apophis has always been at Level 1, which is a negligible threat, but scientists upped that to a level 4 for a short while when discussing the gravitational effect of both earth and the asteroid. Threats On The Horizon
Currently NASA has 959 asteroids that could possibly change course and threaten earth. 5 of those will pass between earth and the moon in the next 100 years; knocking on our door.
2012DA14 had to fly past the moon 7 times before astronomers discovered it. Set to come into close contact with our atmosphere next year, this asteroid is considered a threat because of its irregular shape and size. Just 50 metres in diameter, this hunk of rock would have the power to wipe out a small city on impact. On 15 February 2013, the asteroid will pass less than 24 000 kms from earth, closer than some satellites. So close you’ll be able to observe it with a pair of binoculars.
Some would say this is too close for comfort…
Article written and researched by Policy Expert; UK insurance specialists offering guidance on policies against household damages.
Russia’s space agency wants to send a mission to Apophis, the notorious asteroid which may change its course and eventually collide with Earth. It will plant a radio beacon, which will help track the celestial body and assess the risks it poses.
*The 300-meter-wide asteroid first made headlines in 2004, when NASA reported that it has 1 chance in 223 of impacting on our planet in 2029. It was even named after the Ancient Egyptian evil god, archenemy of the sun god Ra.
But additional observations proved that it will pass by at the small, but safe, distance of some 36,000 kilometers from Earth. The close approach however may result in an unpredictable gravitational pull on Apophis, which would change its course and pose a danger in 2036, when it comes back.
To better assess the risks it poses to the civilization the Roscosmos plans a robotic mission to the asteroid, chief Vladimir Popovkin announced on Monday.
The plan is “to land a module on the surface of Apophis and set up a radio beacon there, which will work after the spaceship’s lifetime expires,” he said at the Space Research Institute in Moscow.
The beacon signal will allow astronomers to better calculate Apophis’ movement and the effect of the 2029 Earth flyby. The mission would not be launched before 2020.
Popovkin, who was speaking at a solar system exploration conference, outlined other mid-term plans Roscosmos has. These include a Venus orbiter between 2020 and 2025, which will study the planet’s hot and dense atmosphere. The mission may include a descending probe, although due to the harsh environment it would only work for about one day on the surface.
Another target is Jupiter’s moon Ganymede. Roscosmos plans to send a spacecraft there in 2022 and is currently negotiating with its European counterpart ESA, which has a similar project, over a possible closer collaboration.
Russia also plans a new Mars mission. Popovkin said launching such a spacecraft is no less important after the embarrassing failure of Fobos-Grunt in November 2011. Now engineers will be able to learn from the mistakes of the original attempt to reach the Martian moon.
A more immediate plan is the Luna Glob mission to the Moon scheduled for late 2015. It would include returning a soil sample to Earth and studying it from an orbiter, which would change its altitude from the initial 100 kilometers down to 50 kilometers and later to 500 kilometers. The soil would later be studied for possible extraction of water from it.
“We will allocate our main effort and majority of resources to the moon,” Popovkin said.
ESA’s Herschel Space Observatory captured asteroid Apophis in its field of view during the approach to Earth on January, 5-6, 2013. This image shows the asteroid in Herschel’s three PACS wavelengths: 70, 100 and 160 microns.
CREDIT: ESA/Herschel/PACS/MACH-11/MPE/B.Altieri (ESAC) and C. Kiss (Konkoly Observatory)
View full size image
A European space telescope has captured new images of the huge asteroid Apophis, revealing that the potentially hazardous object is actually bigger than previously thought — and you have a chance to see the space rock yourself in two free webcasts tonight (Jan. 9). Asteroid Apophis has long been billed as a "doomsday asteroid" because of a 2004 study that predicted a 2.7 percent chance of the space rock hitting Earth when it passes within 22,364 miles (36,000 kilometers) of the planet in April 2029, European Space Agency officials said. Later studies proved, however, that the asteroid poses no threat to Earth during that flyby, but astronomers continue to track the object since it will make another pass near Earth in 2036. http://i.space.com/images/i/000/024/...jpg?1357745686
At about 36 hours from the minimum distance (9.3 million miles or 15 million kilometers from Earth), potentially hazardous asteroid Apophis was imaged again with the Virtual Telescope, on Jan. 8, 2013.
CREDIT: G. Masi & F. NocentiniView full size image
Today, ESA officials announced that its infrared Herschel Space Observatory has discovered that Apophis is about 1,066 feet (325 meters) wide, nearly 20 percent larger than a previous estimate of 885 feet (270 m).
"The 20 percent increase in diameter … translates into a 75 percent increase in our estimates of the asteroid's volume or mass," study leader Thomas Müller of the Max Planck Institute for Extraterrestrial Physics in Garching, Germany, said in a statement. [Photos of Near-Earth Asteroid Apophis]
Tonight's two free webcasts will stream live views of Apophis from telescopes in Italy and the Canary Islands tonight (Jan. 10). The webcasts, offered by the stargazing websites Slooh Space Telescope and Virtual Telescope Project, will show Apophis as a bright light moving across the night sky. The asteroid is too small to be seen through small backyard telescopes.
The Slooh Space Camera webcast will begin at 7 p.m. EST (0000 Jan. 10 GMT). The Virtual Telescope webcast will begin an hour later at 8 p.m. EST (0100 GMT). You can watch both live webcasts of asteroid Apophis here on SPACE.com tonight.
Apophis will be just under 9.3 million miles (15 million kilometers) from Earth at the time of tonight’s webcasts, amateur astronomer Gianluca Masi of the Virtual Telescope Project told SPACE.com.
"Alone among all these near-Earth asteroids that have passed our way in recent years, Apophis has generated the most concern worldwide because of its extremely close approach in 2029 and [chances of a] potential impact, albeit small, in 2036," Slooh president Patrick Paolucci said in a statement. http://i.space.com/images/i/000/023/...jpg?1351286735
An artist's rendering of the asteroid Apophis.
CREDIT: European Space Agency
In addition to asteroid Apophis, astronomers regularly scan the night sky for asteroids that may pose a potential impact threat to Earth. NASA's Near-Earth Object Office and Asteroid Watch program is based at the agency's Jet Propulsion Laboratory in Pasadena, Calif.
You can track Apophis directly via the Virtual Telescope Project here: http://www.virtualtelescope.eu/webtv/
The webcast from the Slooh Space Camera can also be seen here: http://events.slooh.com/
Now if I were R Hoagland I'd be saying something like... "The connection here is clear. The year 1,066 was important in history. There was a war! And this asteroid is exactly 1,066 feet in diameter! Get it! It's OBVIOUS!"
Remember that asteroid they discovered back in 2004 that they used to scare everyone to death, claiming that it would just might impact our planet in a few years and cause massive damage to the Earth? Well, it's back in the news, because it's here. And that asteroid, designated 99942 Apophis, will do a friendly fly-by on Jan. 9.
Why friendly? Because on this go-round, it will pass within some 9 million miles from the Earth, according to NASA. Not particularly close, but close enough in this and in future flybys that the near Earth asteroid was designated a "Potentially Hazardous Asteroid." The initial concern was never that it would hit us sooner but later.
When Apophis (named after the Egyptian demon Apep (Apophis in Greek) the Uncreator, purveyor of darkness and chaos, and the nemesis of Ra the Sun God) was first discovered, calculations pointed to a good possibility of the massive asteroid slamming into the Earth in 2029. With a few years and more accurate calculations made through observation, the chances have grown considerably less. And still, current calculations put the asteroid passing close to the Earth in 2029. But there is a certain portion of space that Apophis could fly through that would set the Earth up for a very close flyby on April 13, 2036. In fact, it could soar through -- inside geosynchronous orbit distance -- at about 21,000 miles above the Earth. http://cdn2-b.examiner.com/sites/def...ccf9aa86e8.jpg
And yet, scientists cannot be completely certain that the asteroid will maintain that kind of distance due to something called as the "Yarkovsky Effect," a process whereby the heating and cooling of the surface of the asteroid as it rotates in its orbit past the Sun affects the space rocks orbit. Deviations caused by the Effect could alter the asteroid's path, resulting in the asteroid passing closer to or farther away from the Earth during each pass.
If Apophis were to actually collide with Earth, it could potentially do great damage. It's size -- 270 meters (855 feet) in width -- and speed could produce an impact equal to 510 megatons, according to NASA. In comparison, the Tunguska Incident (in Russia) was a 3-10 megaton impact and it flattened trees for over 800 miles, was equal to about a thousand Hiroshima-sized atomic bombs, and would have destroyed a large metropolis. Apophis would do roughly 50 times as much damage if it impacted on land and would cause a massive tsunami (resulting in untold amounts of catastrophic damage) if it crashed into an ocean.
In the meantime, scientists will observe and measure and calculate. And hope that the Yarkovsky Effect does not push Apophis closer to future collision course with the Earth.
The flyby can actually be observed from the Earth via large telescopes (but, unfortunately, not your common back yard variety). For those without the mechanical means to view, the Slooh Space Camera will track the near-Earth asteroid online on Jan. 9 and 10.
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If you’re a fan of asteroids, then the name 99942 Apophis will likely mean something to you. It’s an 885-foot-wide asteroid assumed to weigh around 2,727kg. When it was discovered back in 2004 there was a relatively high (2.7 percent) chance this huge asteroid would hit the Earth on April 13, 2029. But later observations ruled that out, however it does remain a potential future threat.
Today, at around about 7pm EST, Apophis is set to closely pass the Earth. By close, I mean within 9 million miles. Astronomers hope this relatively close pass will allow them to take a radar ranging, which will then allow them to better predict the location of the asteroid right up to 2070.
After today’s pass things get a little more worrying, though. The 2029 pass will be much closer at just 30,000km and within range of some satellites. It’s also close enough that most people (in Europe, Africa, and western Asia) will be able to see it in the sky using binoculars. http://www.geek.com/wp-content/uploa...29-439x440.png Predicted April 13, 2029 Apophis Earth approach
Passing so close to Earth will also have a major impact on Apophis’ trajectory, and could allow the asteroid to pass through a half-mile-wide gravitational keyhole setting it up for an impact with Earth in 2036. The chances of that happening are tiny though, and a lot depends on the 2029 pass.
If Apophis did hit Earth the effects would depend a lot on its composition, but the impact is estimated to be the equivalent of 510 megatons. That would do significant damage to an area thousands of square kilometers in size, but would have no long term global effects.
We should know more once the pass today happens and new calculations are made. Then we’ll definitely know if an impact will happen after the 2029 pass, at which point action will have to be taken to divert it if necessary.
Asteroid Could Have Devastating Collision with Earth in 2068
By IBTimes Staff Reporter: Subscribe to IBTimes's RSS feed
February 27, 2013 1:59 PM GMT
The asteroid 99942 Apophis is likely to fly past Earth in 2029 and 2036 without any impact. However, experts believe there is a chance the asteroid (of 270m diameter) could hit our planet on a third fly-by, in 2068. http://img.ibtimes.com/www/data/imag.../27/348819.jpg File photo of Asteroid 99943 Apophis
The good news is the odds of Apophis hitting the planet are only 2.3 in a million, due to need of a very specific gravitational keyhole. A gravitational keyhole is tiny space within which the Earth's gravity can alter a passing asteroid's trajectory, literally turning it on to itself.
The Times of India indicates there was an earlier probability of impact in 2029 and archival data now suggests there are over a dozen keyholes that fall within range of the 2029 impact. However, the probability of Apophis finding one of those keyholes (and the trajectory thereby altering to a 2036 impact) was calculated to be less than one in one million; this almost certainly rules out an impact.
The bad news, though, is that a two-meter keyhole has been isolated and there is 2.3 in a million chance Apophis will find that space. And if it does, scientists expect an impact in 2068.
How Bad Will it Be?
The Sentry Risk Table estimates the asteroid's atmospheric entry would measure 750 megatons of kinetic energy. In comparison, the biggest hydrogen bomb ever exploded measured 57 megatons. The Tunguska event, which was caused by an asteroid in Russia, was estimated to be between three and 10 megatons.
Apophis came under considerable scrutiny in June 2009 because it was believed the 2029 fly-by would, in fact, trigger the gravitational keyhole, leading to an impact with the planet on its next fly-by.
Asteroid Apophis may strike Earth in 2068: Scientists
PTI
Washington, February 27, 2013
First Published: 15:51 IST(27/2/2013)
Last Updated: 19:05 IST(27/2/2013)
http://www.hindustantimes.com/Images...3MediumRes.JPGA simulation of asteroid 2012 DA14 approaching from the south as it passes through the Earth-moon system on Feb. 15, 2013. The 150-foot object will pass within 17,000 miles of the Earth. AP/NASA/JPL-Caltech
A 325-meter asteroid that will safely fly by the Earth in 2029 and 2036, may strike the planet in the year 2068, scientists have warned. However, the chances of 99942 Apophis striking the Earth are slim with impact odds being about 2.3 in a million, the article published on NASA's website said.
The near-Earth asteroid has been the focus of considerable attention after it was discovered in December 2004 to have a significant probability of Earth impact in April 2029.
While the 2029 potential impact was ruled out through the measurement of archival telescope images, the possibility of a potential impact in the years after 2029 continues to prove difficult to rule out.
Based on optical and radar position measurements made in 2004-2012, the asteroid will pass the Earth in 2029 at an altitude of 31900 km, give or take 750 km. The altitude is close enough for the Earth's gravity to deflect the asteroid onto a trajectory that brings it back to an Earth impact during its next flyby.
Such impact trajectories require Apophis to pass the Earth at a precise altitude, known as a keyhole, in 2029 en route to a subsequent impact. "The new report, which does not make use of the 2013 radar measurements, identifies over a dozen keyholes that fall within the range of possible 2029 encounter distances," reads an article prepared by scientists led by Steve Chesley and Davide Farnocchia from Jet Propulsion Laboratory, California Institute of Technology, Pasadena.
The uncertainty in predicting the asteroid' s position in 2029 is completely dominated by the so-called Yarkovsky effect, a subtle non-gravitational perturbation due to thermal re-radiation of solar energy absorbed by the asteroid. Notably, the potential impact in 2036 that had previously held the highest probability has been effectively ruled out since its probability has fallen to well below one chance in one million.
"Only one of the potential impacts has a probability of impact greater than 1-in-a-million, there is a 2-meter wide keyhole that leads to an impact in 2068, with impact odds of about 2.3 in a million," scientists said in the article.
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The potential impact in 2036 that had previously held the highest probability has been effectively ruled out since its probability has fallen to well below one chance in one million.
A recent study has updated the impact hazard assessment for 99942 Apophis, a 325-meter diameter near-Earth asteroid that has been the focus of considerable attention after it was found in December 2004 to have a significant probability of Earth impact in April 2029.
While the 2029 potential impact was ruled out within days through the measurement of archival telescope images, the possibility of a potential impact in the years after 2029 continues to prove difficult to rule out.
Based on extensive optical and radar position measurements from 2004-2012, Apophis will pass the Earth in 2029 at an altitude of 31900 +/- 750 km (about 5 +/- 0.1 Earth-radii above the surface of the Earth).
That altitude is close enough that the Earth's gravity could deflect the asteroid onto a trajectory that brings it back to an Earth impact. Such impact trajectories require Apophis to pass the Earth at a precise altitude, known as a keyhole, in 2029 en route to a subsequent impact.
Recent observations from Pan-STARRS PS1 telescope at Haleakala, Hawaii have reduced the current orbital uncertainty by a factor of 5, and radar observations in early 2013 from Goldstone and Arecibo will further improve the knowledge of Apophis' current position.
However, the current knowledge is now precise enough that the uncertainty in predicting the position in 2029 is completely dominated by the so-called Yarkovsky effect, a subtle nongravitational perturbation due to thermal re-radiation of solar energy absorbed by the asteroid.
The Yarkovsky effect depends on the asteroid's size, mass, thermal properties, and critically on the orientation of the asteroid's spin axis, which is currently unknown.
This means that predictions for the 2029 Earth encounter will not improve significantly until these physical and spin characteristics are better determined.
The new report, which does not make use of the 2013 radar measurements, identifies over a dozen keyholes that fall within the range of possible 2029 encounter distances.
Notably, the potential impact in 2036 that had previously held the highest probability has been effectively ruled out since its probability has fallen to well below one chance in one million.
Indeed only one of the potential impacts has a probability of impact greater than 1-in-a-million; there is a 2-meter wide keyhole that leads to an impact in 2068, with impact odds of about 2.3 in a million.
May be visible to naked eye 2029, may hit Earth 2036.
Lately it seems like the sky is falling. Comets and asteroids are cross-crossing the heavens above as meteors crash down on Earth. Last week there were two major events as meteors came down over central Russia and northern California. Scientists now say that a potential doomsday asteroid will soon pass near Earth, close enough to be visible to the naked eye.
LOS ANGELES, CA (Catholic Online) - Asteroid 99942 Apophis, or just Apophis for short, is on a course that will bring it perilously close to Earth in 2029. There is no question the shave will be close, almost as close as the one we received last week from Asteroid 2012 DA14. The pass will be so close, and Apophis so large, that an astute observer could potentially spot it from the ground without a telescope.
Apophis however, is a genuine killer. Unlike 2012 DA14, which had it hit would have likely vaporized in the atmosphere, Apophis is large enough to survive reentry and strike the surface with enough force to cause a massive tsunami should it land in the ocean, or tens of millions of deaths should it strike a populated area.
The impact would have the equivalent energy of about 510 megatons of TNT. That's much more than the largest atomic bomb ever detonated (Tsar Bomba at 50 megatons) and easily more than the Tunguska and Barringer impacts, between the 3-10 megaton range. In short, a collision with Apophis would devastate a large region of the planet.
However, it would still be far smaller than the Chicxulub event, which wiped out the dinosaurs. Scientists have thankfully ruled out any likelihood of an extinction-level event from Apophis.
Still, the asteroid is massive. Apophis is passing close to Earth right now, and researchers have discovered that it's 20 percent larger than previous estimates. The size of the asteroid has been revised upwards to 325 square meters.
They have also been revising their predictions regarding its orbit.
In 2029, Apophis will pass close enough to Earth to be easily visible to observers on the ground. It may even be visible to the naked eye as a point of light moving steadily across the background of stars over several minutes.
Then, in 2036, it may yet have a greater chance of impacting Earth. Although the odds remain miniscule, they are great enough that scientists have already predicted where it is most likely to land.
If Apophis hits in 2036, it could strike along a path that actually starts quite near the Urals where a meteor famously struck last week. That path then continues across Siberia and into the Pacific near Hawai'i. The danger zone crosses Central America in Nicaragua, and brushes the northern coasts of Colombia and Venezuela. The danger zone ends just off the western coast of Africa.
Odds are, the impact will strike the ocean, creating a devastating tsunami that could kill millions.
Fortunately, the odds are strong that it will miss in 2036.
But what about beyond that? Scientists aren't so sure. Apophis has probably been in its dangerous orbit near Earth for thousands, perhaps millions of years. Or, it could be a new arrival, its current, dangerous orbit only decades old. That much is impossible to tell. Regardless, sooner or later, it seems Earth will have a date with Apophis.
When that happens, we can only hope that scientists and governments around the world have a plan in place to protect us, and the ability to use it. Meanwhile, the rest of us will watch and wait, albeit a bit nervously.
.0634 LD- One LD is 238,900 mi so that's about 15146.26, or about 207,598 nm. The Earth is 21,600 nm in circumference, so about 9 times the distance FROM the Earth as the distance around the earth.
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ESAs Herschel Space Observatory captured asteroid Apophis in its field of view during the approach to Earth on January, 5-6, 2013. This image shows the asteroid in Herschels three PACS wavelengths: 70, 100 and 160 microns. (ESA/Herschel/PACS/MACH-11/MPE/B.Altieri (ESAC) and C. Kiss (Konkoly Observatory))
http://global.fncstatic.com/static/m...jan-8-2013.jpg
Jan. 8, 2013: At about 36 hours from the minimum distance (9.3 million miles from Earth), potentially hazardous asteroid Apophis was imaged again with the Virtual Telescope. (G. Masi & F. Nocentini)
A European space telescope has captured new images of the huge asteroid Apophis, revealing that the potentially hazardous object is actually bigger than previously thought — and you have a chance to see the space rock yourself in two free webcasts tonight.
Asteroid Apophis http://global.fncstatic.com/static/v...ernal-link.pnghas long been billed as a "doomsday asteroid" because of a 2004 study that predicted a 2.7 percent chance of the space rock hitting Earth when it passes within 22,364 miles of the planet in April 2029, European Space Agency officials said. Later studies proved, however, that the asteroid poses no threat to Earth during that flyby, but astronomers continue to track the object since it will make another pass near Earth in 2036.
'Alone among all these near-Earth asteroids that have passed our way in recent years, Apophis has generated the most concern worldwide.'
- Slooh president Patrick Paolucci
Today, ESA officials announced that its infrared Herschel Space Observatory has discovered that Apophis is about 1,066 feet wide, nearly 20 percent larger than a previous estimate of 885 feet.
Tonight's two free webcasts will stream live views of Apophis from telescopes in Italy and the Canary Islands tonight (Jan. 10). The webcasts, offered by the stargazing websites Slooh Space Telescope and Virtual Telescope Project, will show Apophis as a bright light moving across the night sky. The asteroid is too small to be seen through small backyard telescopes.
Apophis will be just under 9.3 million miles from Earth at the time of tonight’s webcasts, amateur astronomer Gianluca Masi of the Virtual Telescope Project told SPACE.com.
"Alone among all these near-Earth asteroids that have passed our way in recent years, Apophis has generated the most concern worldwide because of its extremely close approach in 2029 and [chances of a] potential impact, albeit small, in 2036," Slooh president Patrick Paolucci said in a statement.
In addition to asteroid Apophis, astronomers regularly scan the night sky for asteroidshttp://global.fncstatic.com/static/v...ernal-link.png that may pose a potential impact threat to Earth. NASA's Near-Earth Object Office and Asteroid Watch program is based at the agency's Jet Propulsion Laboratory in Pasadena, Calif.
