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Asteroid Near-Misses (AKA: Holy Shit! We're All Going to Die)

I enjoyed that. It showed clearly that, although the Chelyabinsk object was on a Apollo type orbit, it hit the Earth coming from inside the Earth's orbit, ie "out of the sun", where things are difficult to detect, even if they're much bigger.

But I was disappointed to hear yet again the idea that blowing up an approaching asteroid with a bomb is a No-No - "The Earth would then get hit by a load of fragments instead!"

But I've never heard this argued in detail. As it's well known that smaller objects burn up in the atmosphere, it seems to me that a cloud of fragments must be less dangerous than a single Earth impactor, because most of the fragments would never reach the surface, and those that did would be eroded in the atmosphere and thus far smaller and less dangerous when they did hit land (although the chances are they'd land in the sea instead).

If it's a choice between an impact that could wipe out half the planet, and a few minor strikes that might take out a city or two, I say "Bomb the m*therf*cker to hell!" :twisted:
 
I think the only way of finding out what would happen if exploding an asteroid, is to actually do it. Until then we can never know.

My own favoured method is to cover an asteroid in a super-strong net and attach lots of rocket thrusters. The net would keep the asteroid together for just long enough while the rockets change the asteroid's path.
 
rynner2 said:
If it's a choice between an impact that could wipe out half the planet, and a few minor strikes that might take out a city or two, I say "Bomb the m*therf*cker to hell!" :twisted:
Click to expand...
I've seen Deep Impact, too!
 
1998 QE2: Massive Asteroid to Make 'Royal' Flyby
May 17, 2013 11:41 AM ET // by Mike Wall, Space.com

A big asteroid will cruise by Earth at the end of the month, making its closest approach to our planet for at least the next two centuries.

The May 31 flyby of asteroid 1998 QE2, which is about 1.7 miles (2.7 kilometers) long, poses no threat to Earth. The space rock will come within 3.6 million miles (5.8 million km) of our planet — about 15 times the distance separating Earth and the moon, researchers say.

But the close approach will still be dramatic for astronomers, who plan to get a good look at 1998 QE2 using two huge radar telescopes — NASA's 230-foot (70 meters) Goldstone dish in California and the 1,000-foot (305 m) Arecibo Observatory in Puerto Rico.

"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," Lance Benner of NASA's Jet Propulsion Laboratory in Pasadena, Calif., principal investigator for Goldstone radar observations, said in a statement.

"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," Benner added.

Asteroid 1998 QE2 was discovered in August 1998 by astronomers working with MIT's Lincoln Near Earth Asteroid Research (LINEAR) program in New Mexico.
The space rock's name is not an homage to England's Queen Elizabeth II, or to the famous 12-deck ocean liner that was retired from service in 2008. It's just the moniker assigned by the Minor Planet Center in Cambridge, Mass., which names each newfound asteroid according to an established alphanumeric scheme that lays out when it was discovered.

Astronomers plan to study 1998 QE2 intensively from May 30 through June 9, using the Goldstone and Arecibo dishes to learn as much as possible about the asteroid before it slips off once more into the depths of space.

Even from about 4 million miles (6.4 million km) away, Goldstone images may be able to resolve features on 1998 QE2 as small as 12 feet (3.75 m) across, researchers said.
"It is tremendously exciting to see detailed images of this asteroid for the first time," Benner said. "With radar we can transform an object from a point of light into a small world with its own unique set of characteristics. In a real sense, radar imaging of near-Earth asteroids is a fundamental form of exploring a whole class of solar system objects."

NASA leads the global effort to identify potentially dangerous asteroids. Our planet has been pummeled by space rocks throughout its 4.5-billion-year history, and more strikes are in our future.

The planet got a dramatic reminder of this reality this past Feb. 15. On that day, a 55-foot (17 m) object exploded without warning over Russia, just hours before the 130-foot asteroid 2012 DA14 gave Earth a close shave, missing our planet by just 17,200 miles (27,000 km).

http://news.discovery.com/space/asteroi ... 130517.htm
 
A reminder about QE2:

Asteroid 1998 QE2 set for Earth fly-by
By Rebecca Morelle, Science reporter, BBC World Service

An asteroid that measures nearly 2.7km (1.7 miles) across is set to fly past the Earth.
The space rock, which is called 1998 QE2, is so large that it is orbited by its own moon.

It will make its closest approach to our planet at 20:59 GMT (21:59 BST), but scientists say there is no chance that it will hit.
Instead it will keep a safe distance - at closest, about 5.8 million km (3.6 million mi).

That is about 200 times more distant than the asteroid "near-miss" that occurred in February - but Friday's passing space rock is more than 50,000 times larger.

Prof Alan Fitzsimmons, an astronomer at Queen's University Belfast, said: "It's a big one. And there are very few of these objects known - there are probably only about 600 or so of this size or larger in near-Earth space.
"And importantly, if something this size did hit us one day in the future, it is extremely likely it would cause global environmental devastation, so it is important to try and understand these objects."

This fly-by will give astronomers the chance to study the rocky mass in detail.
Using radar telescopes, they will record a series of high-resolution images.
They want to find out what it is made of, and exactly where in the Solar System it came from.

Prof Fitzsimmons said: "We already know from the radar measurements, coupled with its brightness, that it appears to be a relatively dark asteroid - that it's come from the outer part of the asteroid belt."

Early analysis has already revealed that the asteroid has its own moon: it is being orbited by another smaller piece of rock that is about 600m (2000ft) across.
About 15% of asteroids that are large are "binary" systems like this.

This celestial event will not be visible to the naked eye, but space enthusiasts with even a modest telescope might be able to witness the pass.

After this, asteroid 1998 QE2 will hurtle back out into deep space; Friday's visit will be its closest approach for at least two centuries.

Researchers are becoming increasingly interested in potential hazards in space.
So far they have counted more than 9,000 near-Earth asteroids, and they spot another 800 new space rocks on average each year.

http://www.bbc.co.uk/news/science-environment-22736709
 
Russian meteor shockwave circled globe twice
By Simon Redfern, Reporter, BBC News

The shock wave from an asteroid that burned up over Russia in February was so powerful that it travelled twice around the globe, scientists say.
They used a system of sensors set up to detect evidence of nuclear tests and said it was the most powerful event ever recorded by the network.
More than 1,000 people were injured when a 17m, 10,000-tonne space rock burned up above Chelyabinsk.
The study appears in the journal Geophysical Research Letters.

The researchers studied data from the International Monitoring System (IMS) network operated by the Comprehensive Nuclear-Test-Ban Treaty Organisation (CTBTO).
The detection stations look out for ultra-low frequency acoustic waves, known as infrasound, that could come from nuclear test explosions. But the system can also detect large blasts from other sources, such as the Chelyabinsk fireball.

Alexis Le Pichon, from the Atomic Energy Commission in France and colleagues report that the explosive energy of the impact was equivalent to 460 kilotonnes of TNT. This makes it the most energetic event reported since the 1908 Tunguska meteor in Siberia.

Meanwhile, another team of scientists has published a study focusing on the Tunguska event.
The 1908 fireball, the biggest space impact of modern times, was probably caused by an iron-rich meteorite, a study in the journal Planetary and Space Science has confirmed.

The Tunguska air blast is estimated to have been equivalent to three to five megatonnes of TNT, hundreds of times more energetic than the Hiroshima explosion, and it flattened trees across 2,000 sq km of forest.

Victor Kvasnytsya, from Ukraine's National Academy of Sciences, and colleagues studied microscopic samples of mineral debris from the blast area that have been trapped in peat.
In their paper, they describe the mineralogy of samples recovered from the peat in the 1970s and 80s. High-resolution imaging and spectroscopy identified carbon minerals such as diamond, lonsdaleite and graphite.

Lonsdaleite in particular is found in carbon-rich material subjected to a shock wave, and is typically formed in meteorite impacts.
The lonsdaleite fragments contain smaller inclusions of iron sulphides and iron-nickel alloys, troilite and taenite, which are also characteristic meteorite minerals.

The iron to nickel ratio and the precise combinations of minerals assembled in these small fragments all point to a meteorite source, and are nearly identical to similar minerals found in the Canyon Diablo meteor that impacted Barringer Crater (Meteor Crater) in Arizona.

The findings would appear to rule out a theory that the Tunguska airburst was caused by a large fragment of Comet Encke. This comet is responsible for a meteor shower called the Beta Taurids, which cascade into Earth's atmosphere in late June and July - the time of the Tunguska event.

http://www.bbc.co.uk/news/science-environment-23066055
 
Russian Chelyabinsk meteorite pieces go under microscope
http://www.bbc.co.uk/news/science-environment-23284371

SEM of Chelyabinsk meteor fragment

Often referred to as the Chebarkul meteorite after the lake where many pieces were found, the space rock appears to be a standard "chondrite"

Scientists have released microscopic images of fragments of the meteorite that hit central Russia in February.

A team from the Ural Federal University was able to analyse some of the dozens of samples as soon as they were found.

But the technique they used allowed them to assess the rock's chemical make-up at the microscopic level even as they snapped pictures of the fragments.

This will provide extra information on the space rock's formation and journey.

The fragments represent just a small portion of the remains of the 17m-diameter body that struck the Earth's atmosphere in a spectacular trail of light over the city of Chelyabinsk.

The team, led by Urals Federal University's Viktor Grokhovsky, determined right away that the overall chemistry of the meteorite was a familiar "chondrite".

"The fragments contain a standard number of minerals, including olivine, pyroxene, troilite and kamacite. These minerals that can be discovered only in outer space confirm the fragments' extraterrestrial nature," he told the Voice of Russia at the time.

But far more information was in the offing.

SEM of Chelyabinsk meteor fragment
The way differing minerals are laid out gives clues as to their origin and their journey
The team was using a scanning electron microscope, which fires a beam of electrons focused onto a tiny part of a sample, scanning around to see how the electrons are deflected and thereby building up a detailed picture of the sample's nanometre-scale bumps and valleys.

But that process causes the emission of a small amount of X-ray radiation - with the exact energy of the X-rays corresponding to the chemical element present in the focus of the electron beam.

This is where a silicon drift detector comes in - harvesting these X-rays and determining their energy. The result is a series of what are called X-ray maps - pictures of the same sample showing the presence and quantity of different elements.

It is this understanding of the minerals at a microscopic level that goes far beyond simply telling us what the meteorite is made of, said Simon Burgess of Oxford Instruments, which made the X-max silicon drift detector used by the team.

"For the researchers who are looking at this meteorite, it's going to be telling them information about which (mineral) phase is associated with which," he told BBC News.

"When they get into more detail beyond what the main chemistry of the meteorite is, they may be looking at processes in terms of how it formed, the temperature it formed at, what its history has been since its formation, possibly things about what happened to it during its impact with the Earth.

"A lot of that you cannot tell just by crushing it up and getting a 'bulk analysis'; you have to look at the chemistry of the individual parts and associations between the different minerals in the meteorite."

The X-max technology is in the running for the Royal Academy of Engineering's MacRobert Award, to be announced on Friday 19 July.

Composite image of X-max images

The X-ray maps show the precise distribution of individual chemical elements
Click to expand...
 
The best is yet to come?

Chelyabinsk meteorite may have gang of siblings – study
http://rt.com/news/chelyabinsk-meteorit ... study-058/

The Chelyabinsk meteor trace. (RIA Novosti / Nakanune.RU)The Chelyabinsk meteor trace. (RIA Novosti / Nakanune.RU)

Russia, SciTech, Science, Security, Space
The Chelyabinsk meteorite that hit Russia in February, injuring over a thousand, may have stemmed from a massive cluster of rocks which broke off from a disintegrating asteroid thousands of years ago, a new study claims.

Spanish astronomers have discovered that the Chelyabinsk bolide, an 18-meter wide 11,000-ton space rock that burst in a 460-kiloton explosion above Russia, used to be a part of a larger space body.

Scientists believe between 20,000 to 40,000 years ago, a massive body orbiting the sun broke up, most likely as a result of the temperature extremes and planetary gravitation it experienced while looping out past Mars and Venus.

Subsequently, the pieces of that asteroid formed a so-called ‘asteroid family’, a group of asteroids that share same origin, composition and orbit. The parent of this potentially hazardous asteroid family has been identified as 2011 EO40. Those rocks are still flying somewhere in space, and just like the Chelyabinsk meteorite, their orbits could intersect with that of Earth.

In a new study, Carlos de la Fuente Marcos and his brother Raul from the Complutense University in Madrid said that they have found reliable statistical evidence for the existence of the Chelyabinsk cluster, or asteroid family.

The brothers used computer simulations of billions of possible asteroid orbits to find the ones most fitting into the Chelyabinsk impactor pre-collision orbit. They then searched the NASA database of known asteroids to find out if any of them follow those orbits. In the course of their investigation, they spotted the Chelyabinsk bolide family of about 20 asteroids, which range in size from 5 to 200 meters across.

“It appears to include multiple small asteroids and two relatively large members: 2007 BD7 and 2011 EO40. The most probable parent body for the Chelyabinsk superbolide is [asteroid] 2011 EO40,” according to their article, which is to be published in Monthly Notices of the Royal Astronomical Society: Letters.

The study points out that the shattered pieces of a rubble-pile asteroid can spread along the entire orbit of the parent body, making their collision with Earth possible on a time-scale of hundreds of years.

Fragments of the Chelyabinsk meteorite are studied at the laboratory of the Research and Educational Center of Nanomaterials and Nanotechnologies of Ural Federal University. (RIA Novosti / Pavel Lisitsyn) Fragments of the Chelyabinsk meteorite are studied at the laboratory of the Research and Educational Center of Nanomaterials and Nanotechnologies of Ural Federal University. (RIA Novosti / Pavel Lisitsyn)

The Spaniards do admit that the orbits of the Chelyabinsk bolide asteroid family have not been definitively calculated and there is room for debate about whether they are a ‘family’ at all. The Spanish researchers also said the gravitational pull of the planets may affect the paths of the other rocks in the cluster in a slightly different way, so even if the orbits of these objects initially seem similar, they could radically change down the line.

Still, Carlos de la Fuente Marcos warns, “More objects with the same orbital signature may encounter our planet in the future”.

With a diameter of some 200 meters, 2011 EO40 has already been labeled a potentially hazardous asteroid (PHA) by the Minor Planet Center (MPC). It was first classified as an Earth crosser upon its discovery in 2011. So far its orbit has not been entirely calculated, being modeled on a mere 34 days of observations, whereas it usually takes years of follow-ups of a space object to know its trajectory with certainty.

Jorge Zuluaga from the University of Antioquia in Colombia has doubts if 2011 EO40 is in fact the parent of the Chelyabinsk meteor and isn’t worried about it creating further impacts.

“I don’t think this particular asteroid is more hazardous than others in the MPC list,” said Zuluaga, adding that the asteroid isn’t on a direct collision course with Earth in any case.

David Nesvorny from the Southwest Research Institute in Boulder Colorado was also skeptical of a definite link.

“It is not obvious to me why [the Chelyabinsk meteor] cannot be a fragment that was produced by a collision in the main asteroid belt, and evolved to its impact orbit by a few planetary encounters,” he told the journal Nature.

Further tests would be needed to confirm if 2011 EO40 was Chelyabinsk’s parent rock. Sending a probe into space to bring back samples is the only way to be completely sure. Another cheaper and a less conclusive option would be to analyze the light bouncing off it and collate its composition to fragments of the meteorite that hit Russia.
Click to expand...
 
Presumed meteorite pulled from lake

Divers working at a Russian lake have recovered what may be a 570kg chunk of the space rock that exploded over Chelyabinsk earlier this year.
The object is thought to have plunged into Lake Chebarkul in central Russia leaving a 6m-wide hole in the ice.
If confirmed, it would be the largest fragment of the meteorite yet found.

More than 1,000 people were injured when a 17m, 10,000-tonne space rock burned up over Russia on 15 February.

Live footage showed a team pull out a 1.5-metre-long (five-foot-long) rock from the lake after first wrapping it in a special covering and placing it on a metal sheet while it was still underwater.
The boulder was then pulled ashore and placed on top of a scale for weighing, an operation that quickly went wrong.
The rock broke up into at least three large pieces as it was lifted from the ground with the help of levers and ropes.

Then the scale itself broke, the moment it hit the 570kg (1,255lb) mark. :shock:

But scientists cautioned that it would take time before they could verify that the rock pulled from the lake had indeed come from space.

The divers' mission had been hampered by a number of factors. The rock fragment lay at 13m depth, not 6m or 8m as was originally thought.

The Vesti 24 rolling news channel reported that divers had already recovered more than 12 pieces from Lake Chebarkul since the incident on 15 February.
The station cautioned that only four or five of them had turned out to be real meteorites.

http://www.bbc.co.uk/news/science-environment-24550941
 
United Nations to lead efforts to defend Earth from asteroids
The United Nations plans to coordinate international efforts to defend the Earth from the threat posed by asteroids
By Richard Gray, Science Correspondent
7:01AM GMT 30 Oct 2013

The United Nations is to lead international efforts to create plans to defend the Earth from asteroids that pose a collision risk.
The UN’s Action Team on Near Earth Objects is to work with space agencies around the world to draw up potential missions in response to asteroid threats.
It will also help to establish a global network to provide an early warning system for any near earth objects that may pose a risk to the Earth.

The plans were set out in a series of recommendations endorsed at a meeting of the UN’s Fourth Committee of the General Assembly.
They have yet to be adopted as a resolution by the full General Assembly but are expected to be fully implemented and will require member nations to cooperate to protect the Earth from asteroid collisions.

Missions to deflect an asteroid are likely to be launched years in advance of a potential impact to gently push any threats off course.
Experts believe missions that use [of] rockets, solar sails or gravity tractors to change an asteroid's orbit as the most likely solutions.

Missions that attempt to destroy an asteroid, such as those used in the film Armageddon and Deep Impact, are less likely due to the risk posed by the resultant debris.

The UN meeting comes eight months after a 55 feet wide meteor exploded high in the sky above Chelyabinsk, Russia, creating widespread damage.
The meteor, which had not been previously detected, exploded with the force of more than 30 Hiroshima nuclear bombs high in the atmosphere.

Astronomers estimate that there are more than one million asteroids that are in a near Earth orbit around the sun.
There are currently just 10,000 asteroids being tracked by Nasa’s Near Earth Object Program.

Professor Richard Crowther, former chair of the UN Working Group on Near Earth Objects and head of the UK space delegation to the UN, said the steps taken by the UN would lead to greater global cooperation on how to tackle asteroids.
He said: “If you are trying to change the orbit of an asteroid so that it misses the Earth, there are not just technical considerations that need to have been rehearsed but also political ones.
“Which way would you deflect it and what would happen if it did not deflect enough? Would you deflect it over areas where there were least population or least infrastructure.

“Then there is the question of who has the authority to act on behalf of humanity.
“The recommendations put before the UN General Assembly will see the establishment of a network to identify asteroids and work out if they are likely to hit the Earth.
“There is also a framework to form a collection of space agencies that will work collectively to come up with [a] mission to deflect or mitigate a potential impact identified by the warning network.
“These will probably not be formal UN entities but the UN would probably have oversight.”

Scientists have found that the Chelyabinsk meteor broke off a much larger asteroid that is in orbit around the sun and have not ruled out that other debris from the same source could also be on a collision course with the Earth.
The meteor caused 1,000 injuries when it exploded high in the Earth’s atmosphere.
Had it exploded at a lower altitude or over a more densely populated area, then the destruction could have been far worse.

The UN endorsement of international collaboration to tackle such threats in the future came as the Association of Space Explorers, an organisation formed of former astronauts, gathered for a conference to discuss the threat posed by asteroids.
They first took a series of recommendations for how the world could tackle the threat posed by near Earth asteroids to the UN in 2007.
At a meeting last week at the American Museum of Natural History in New York members of the ASE spoke about the importance of international collaboration.

They also promoted the launch of a new $450 million private space-based telescope designed to spot asteroids approaching.
The B612 Foundation, co-founded by former Apollo astronaut Russel Schweichart, is raising money for the space telescope – called Sentinel – that they aim to launch in 2017.

Thomas Jones, a former Nasa astronaut and member of the ASE, said: “We’ve all been up in orbit and seen impact craters around the globe as we have circled our planet.
“Asteroid impacts have dramatically altered the course of life on Earth and a rogue asteroid will certainly strike Earth, posing a global threat to human life and society.
“Search efforts to date have discovered scarcely 1% of potentially hazardous near-Earth objects, and current telescopes were unable to warn us of the February 2013 Chelyabinsk impact.
“This leaves 99% of the objects big enough to level a major metropolitan area – undiscovered.”

The recommendations enforced by the UN’s Fourth Committee of the Advisory Council set out the need to establish an “International Asteroid Warning Group” – a network of telescopes and astronomers working together to identity, map and predict the path of asteroids.

A “Space Missions Planning Advisory Group” would also see national space agencies to prepare technology and ensure plans are in place for missions to deflect an asteroid if necessary.
Mr Jones added: “The planning that group does will then be available to the world’s space agencies to actually deflect a rogue object.
“UN Committee on Peaceful Uses of Outer Space is going to monitor detections and help plan a deflection campaign if that is necessary.”

There are a number of asteroids that are currently deemed to pose a potential risk to the Earth in the future.
Earlier this month scientists said they had identified a 1,345 feet wide asteroid that could pass close enough to risk hitting the Earth in 2032.

Professor Crowther said: “There are a number of characteristic asteroids that may come to us and we need to look at what missions are most appropriate.
“We need to look at the technology we would need to deliver those missions, such as accurate homing, interception and propulsion, and how long it will take to build these up.
“It means when you actually need to use them in anger, you have some confidence that they will work. It will inform the technology road maps of the space agencies.
There is no single country that has all the technology required to do this end it is much easier to work together to have an international collaboration.”

http://www.telegraph.co.uk/science/spac ... roids.html

...just as long as it's not another layer of bureaucracy to slow everything down. "Shouldn't we take a vote on that?"
 
Chelyabinsk meteor: Space rock hit-rate 'underestimated'
http://www.bbc.co.uk/news/science-environment-24839601
By Rebecca Morelle
Science reporter, BBC World Service

Archive: Eyewitnesses and CCTV cameras captured the moment the meteor flew across the sky in Russia in February

The threat of another asteroid strike like the one that hit Russia earlier this year is much higher than was previously thought, a study suggests.

Researchers have found that space rocks of a similar size to the one that exploded over Chelyabinsk are hurtling into the Earth's atmosphere with surprising frequency.

Scientists say early warning systems need to be put in place.

The study is published in the journal Nature.

Lead author Professor Peter Brown, from the University of Western Ontario, Canada, told the BBC World Service's Science in Action programme: "Having some sort of system that scans the sky almost continuously and looks for these objects just before they hit the Earth, that probably is something worth doing.

"In the case of Chelyabinsk, a few days' to a week's warning would have been valuable."

Fireball

The asteroid that exploded over Russia on 15 February this year was estimated to be about 19m-wide.

Continue reading the main story
“
Start Quote

There are literally millions of objects in the tens of metres of size range that we suspect are near Earth asteroids”

Prof Peter Brown
University of Western Ontario
It hit the atmosphere with energy estimated to be equivalent to 500,000 tonnes of TNT, sending a shockwave twice around the globe. It caused widespread damage and injured more than 1,000 people.

Now though, scientists say there could be many more space rocks like this one on a collision course with the Earth.

An international team looked at the last 20 years of data collected from sensors used by the US government and infrasound sensors positioned around the globe.

These detectors are in place to detect the threat of nuclear weapons, but they can also capture the blasts caused by asteroid impacts.

The researchers found that during this time about 60 asteroids up to 20m in size had smashed into the Earth's atmosphere: far more than was previously thought

Most went undetected because they exploded over the ocean or in very remote areas.

Prof Brown explained: "We were able to capture the occurrence rate you would expect of things like Chelyabinsk and smaller impacts. When you compare that to the numbers you get from telescopic [observations], our numbers are several times higher."


Archive: Divers recently recovered a large piece of the Chelyabinsk meteorite from a lake
This suggests that the risk from asteroids of this scale has been underestimated. The team estimates that the strike rate of asteroids that are tens of metres in size is between two and 10 times higher than was previously thought.

"Something like Chelyabinsk, you would only expect every 150 years on the basis of the telescopic information. But when you look at our data and extrapolate from that, we see that these things seem to be happening every 30 years or so," said Prof Brown.

An event such as the Tunguska impact in 1908, where an asteroid flattened thousands of square kilometres of forest in Siberia, would probably happen every few hundred years rather than every few thousand years, he added.

The trail of a falling object is seen above a residential apartment block in the Urals city of Chelyabinsk
Many people in Russia caught the Chelyabinsk meteor on camera
Prof Brown said more effort should be made to create early warning systems.

"There are literally millions of objects in the tens-of-metres-of-size range that we suspect are near Earth asteroids, that can get close to the Earth," he said.

"We have only discovered over 1,000 of these. There are many more of these to find, but it would be very expensive to find all of these and it probably wouldn't make a lot of sense because the atmosphere largely stops them.

"But what might make sense are systems that find something a few days or weeks before they hit... to tell you where on the Earth and when they will hit. That would allow some warning to be given to the civil defence authorities."

In another study, also published in Nature, scientists believe they have traced the asteroid that the Chelyabinsk meteor splintered off from.

They think it is a fragment of a 2km-wide rock called asteroid 86039.

Professor Jiri Borovicka, from the Academy of Sciences of the Czech Republic, said the orbits were "conspicuously similar", although the team could not prove "the common origin with absolute certainty".
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Gays caused Chelyabinsk meteorite? Russian LGBT community accuses TV show of hate speech
Published time: November 15, 2013 03:02 Get short URL
http://rt.com/news/meteorite-lgbt-russia-mamontov-749/

RIA Novosti / Anatoly MedvedRIA Novosti / Anatoly Medved

A Russian TV host has made quite a peculiar remark linking the Chelyabinsk meteorite and the country’s gay movement. Russia’s LGBT community reacted angrily and asked prosecutors to check the host’s show for hate speech.

In a reference to the Old Testament story of the cities of Sodom and Gomorrah, famous journalist Arkady Mamontov said on his program that the fall of the Chelyabinsk meteorite on February 15 in Russia was related to the country’s growing gay activity. Mamontov’s program ‘Special Correspondent’ airs on state channel Rossiya 1.

The host called the meteorite a warning "to all of us that we should keep the family tradition, traditional love, or else something else - not only the Chelyabinsk meteorite - will hit us."

The Russian LGBT Network rights group filed a complaint with the prosecutor’s office on Thursday. The group accused the show of hate speech, according to group chairman Igor Kochetkov. He said that Mamontov also claimed that gays and lesbians want to "destroy [traditional] Russia.”

Arkady Mamontov (RIA Novosti / Ruslan Krivobok) Arkady Mamontov (RIA Novosti / Ruslan Krivobok)

A Special Correspondent episode aired on Tuesday included the new documentary film ‘Litsedei’ (Hypocrites), which tells of the alleged threat from Western countries that are trying to carry out a “gay revolution” in Russia by organizing a protest movement based on claims that homosexuals are oppressed.

The film also alleges that conferences of the LGBT community in Russia are sponsored from abroad - in particular by the fund of American business magnate George Soros.

In a statement on the website of the Association of Russian Lawyers for Human Rights, lawyer and human rights activist Maria Bast – who was featured in the documentary – accused the makers of slander and misrepresentation. She went on to say that the film reflected intolerance and fascism.

Russia’s leading LGBT activist and lawyer, Nikolay Alekseev, has submitted a request to Moscow authorities to gain permission to stage a protest against Mamontov’s show. He also said on his Facebook page that he gave a two-hour interview to the filmmakers but that none of it was aired.
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NASA warns of 'potentially hazardous' asteroid
Published time: January 10, 2014 17:55
Edited time: January 11, 2014 09:37

This artist's concept shows the Wide-field Infrared Survey Explorer, or WISE spacecraft, in its orbit around Earth. In September of 2013, engineers will attempt to bring the mission out of hibernation to hunt for more asteroids and comets in a project called NEOWISE. (NASA/JPL-Caltech)

A new, “potentially hazardous” asteroid has been discovered by one of NASA’s recently reactivated spacecraft – and it’s headed in Earth’s direction.

The new asteroid, called 2013 YP139, was spotted by NASA’s Near-Earth Object Wide-field Infrared Survey Explorer (NEOWISE), and marks the spacecraft’s first discovery since being resurrected last year.

According to the Telegraph, the asteroid is still 27 million miles (43 million km) away from Earth, but with a diameter of nearly half a mile (0.4 miles, to be precise), an impact with our planet would cause significant damage. NASA estimates any asteroid with a diameter greater than 0.5 miles could create worldwide consequences upon impact.

The 2013 YP139 doesn’t quite raise concern to that level, but its trajectory has attracted the attention of NASA.

Fortunately, the space agency added that the asteroid will miss the Earth this time around, though it will fly by our planet at a distance of 300,000 miles, or about as close as the moon. It’s not expected to get any closer for the next century.

Before going into “hibernation,” the NEOWISE had discovered more than 34,000 asteroids in 2010 and 2011, with potentially hundreds of discoveries ahead. The spacecraft scans what’s typically a static space background, looking for disruptions it can follow and analyze.

"We are delighted to get back to finding and characterising asteroids and comets, especially those that come into Earth’s neighborhood," said Amy Mainzer of NASA’s Jet Propulsion Laboratory, who is leading the mission, according to the Huffington Post."With our infrared sensors that detect heat, we can learn about their sizes and reflectiveness."

In this image, X-ray light seen by Chandra with energy ranges of 0.5 to 2 kiloelectron volts (keV) and 2 to 4 keV is shown in red and green, respectively, while X-ray light detected by NuSTAR in the higher-energy range of 7 to 25 keV is blue. (Image credit: NASA/JPL-Caltech/McGill)In this image, X-ray light seen by Chandra with energy ranges of 0.5 to 2 kiloelectron volts (keV) and 2 to 4 keV is shown in red and green, respectively, while X-ray light detected by NuSTAR in the higher-energy range of 7 to 25 keV is blue. (Image credit: NASA/JPL-Caltech/McGill)

While this NASA spacecraft detects potentially dangerous objects, however, one of the agency’s telescopes just captured a remarkable image of space that’s been termed the “Hand of God.”

Although scientists aren’t sure if the shape in the image is an optical illusion, the result of a dying star 17,000 light years away has been the formation of an image that resembles a hand under an X-Ray.

According to scientists from the Nuclear Spectroscopic Telescope Array (NuSTAR) Mission – which investigates black holes, dying stars and more – the star’s particles are interacting with neighboring magnetic fields, causing a glowing reaction. The star is approximately 12 miles in diameter and spins about seven times every second.
http://rt.com/usa/nasa-warns-potentiall ... eroid-428/
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Please note how the object flares, and sheds bits.

This is characteristic of meteors, and if you see such a thing in the night sky, be fairly sure no little green men are involved.

That's also something that gives away a pyrotechnic device, the two are quite similar. And the doomed space shuttle looked a lot like it.

One would suppose that an extraterrestrial craft would be under control. And that it intended a landing, not a crash. Just a guess, now, circumstances might make it otherwise.

There are so few mysteries left, alas.
 
This is a funny one.

I suspect it's just down to human failings, but it's still a mystery:

http://www.newscientist.com/article...oid-goes-missing-near-earth.html#.UwedQ_l_uSp

Incoming 'Moby Dick' asteroid goes missing near Earth

A whale of an asteroid has gone missing. The 270-metre space rock known as 2000 EM26 was slated to skim past Earth early on 18 February, coming within 3.4 million kilometres of our planet. But when a robotic telescope service trained its eye on the predicted position, the asteroid was nowhere to be found.

Astronomers coordinating the telescope service, called Slooh, have nicknamed the elusive asteroid Moby Dick after the fictional white whale, and have issued a call to amateur sky-watchers to help hunt it down.
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Rest of article is at the link...
 
98-foot asteroid flashes between moon and Earth within 24 hours
Published time: March 04, 2014 16:08
Edited time: March 05, 2014 11:51
http://rt.com/news/asteroid-flyby-earth-moon-783/

This NASA image shows an artist's animation that illustrates a massive asteroid belt (AFP Photo / NASA / JPL Caltech)

An Apollo class asteroid is expected to whizz between the Earth and the moon on March 5. The 98-foot-wide space rock is expected to come within 218,000 miles of earth (0.9 lunar distances), creating quite a sight for stargazers.

The asteroid, named 2014 DX110, is expected to make its closest approach at 21:07 GMT on Wednesday at a blistering speed of 14.85 km/s (32,076 mph). Although the space rock poses no threat to earth, it highlights its susceptibility to near-Earth asteroids.

For amateur astronomers interested in watching the fly-by as it happens, the virtual telescope project will offer live coverage via Slooh, which allows viewers to peer through a telescope via the web.

DX110 belongs to the Apollo class of asteroids, a group of Earth-crossing asteroids, which pose a potential threat to humankind. The February 15, 2013, 65-foot-wide meteor, which exploded over the town of Chelyabinsk in the southern Urals Region of Russia, belonged to the Apollo class. The meteor explosion was 30 times stronger than the Hiroshima atomic bomb. As windowpanes shattered throughout the city, 1,500 people were injured, but luckily no one was killed.

Nearly one year after the Chelyabinsk atmospheric extravaganza, another massive asteroid sailed past the Earth. The space-rock known officially as 2000 EM26 had an estimated diameter of 885 feet, roughly the equivalent of three football fields. It however, only came within some 2,094,400 miles of Earth.

Based on the orbits of such space rocks, many of them are likely originate in "the asteroid belt between Mars and Jupiter. While DX110 will come nearly ten times closer to Earth than the exponentially larger EM26, another asteroid – 2012 DA14 – came within 17,200 miles of the Earth’s surface. In an amazing cosmic coincidence, DA14 made its near-earth flyby on the exact same day the Chelyabinsk impacter hit. Scientists say if the 150ft-wide had hit Earth, it would have had enough destructive power to level a major metropolis the size of Moscow or London.

And last week, a 400 kg meteor slammed into the moon at a speed of 36,600 mph, leaving behind a 40-meter-wide crater.

An image grab taken from a video uploaded on YouTube by user @wowforreeelAn image grab taken from a video uploaded on YouTube by user @wowforreeel

Meanwhile, Researchers say that space rocks of a similar size to the one that exploded over Chelyabinsk are hurtling into the Earth's atmosphere with surprising frequency.

Last November, scientists writing for the journals Nature and Science reported that the likelihood of a space rock similar in size to the Chelyabinsk meteor was up to seven times more likely to strike the earth than previously believed, AP reported.

In total, that means about 20 million space rocks the size of the Chelyabinsk one may be speeding through our solar system, and not 3 million, said NASA scientist Paul Chodas.

Previously, scientists believed that such airburst events as happened over the Urals only occur approximately once every 150 years. Now the frequency of such an event is estimated to be every 30 years.

Scientists say early warning systems need to be put in place in order to safeguard against future events.
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Hubble watches asteroid break into pieces without being involved in a collision.
http://www.universetoday.com/110044/hubble-telescope-watches-asteroid-disintegrate-in-space/

More plus pictures from Hubble of the asteroid at the link

"Asteroid P/2013 R3 appears to be crumbling apart in space, and astronomers using the Hubble Space Telescope recently saw the asteroid breaking into as many as 10 smaller pieces. The best explanation for the break-up is the Yarkovsky–O’Keefe–Radzievskii–Paddack (YORP) effect, a subtle effect from sunlight that can change the asteroid’s rotation rate and basically cause a rubbly-type asteroid to spin apart.

“This is a really bizarre thing to observe — we’ve never seen anything like it before,” said co-author Jessica Agarwal of the Max Planck Institute for Solar System Research, Germany. “The break-up could have many different causes, but the Hubble observations are detailed enough that we can actually pinpoint the process responsible.”
 
Nasa seeks coders to hunt asteroids
http://www.bbc.com/news/technology-26528516

Artist conception of dwarf planet Ceres in the main asteroid belt

Better code could help identify where asteroids are heading

US space agency Nasa is seeking coders who could help prevent a global catastrophe by identifying asteroids that may crash into Earth.

Its Asteroid Data Hunter contest will offer $35,000 (£21,000) to programmers who can identify asteroids captured by ground-based telescopes.

The winning solution must increase the detection rate and minimise the number of false positives.

Scientists are increasingly calling for help to make sense of vast data sets.

The new improved asteroid hunting code must also be able to ignore imperfections in the data and run on all computer systems.

"Protecting the planet from the threat of asteroid impact means first knowing where they are," said Jenn Gustetic, executive of the programme.

"By opening up the search for asteroids, we are harnessing the potential of innovators and makers and citizen scientists everywhere to solve this global challenge."

Current asteroid detection is only tracking one percent of the estimated objects that orbit the sun, according to asteroid mining firm Planetary Resources, which is partnering with Nasa in the contest.

Human curiosity
Zooniverse is one of the leading online platforms for citizen scientists, working on a range of projects including classifying galaxies.

In February it racked up one million volunteers.

"Nasa takes these detailed pictures but there is a lot of noise out there from stars and other things and we need to write code that can find patterns in the data," said Zooniverse team member Robert Simpson.

"This is not necessarily Nasa's area of expertise. It is a technology problem rather than a space problem."

He thinks that increasingly citizen scientists can contribute to important scientific discoveries and breakthroughs.

"Computers don't have curiosity. People often find things in the data that computers can't," he told the BBC.

"We are creating these huge data sets but we don't have enough scientists to analyse them," he added.
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Not a near miss: a double strike.

Ancient Earth hammered by double space impact
By Paul Rincon
Science editor, BBC News website
http://www.bbc.com/news/science-environment-26172181

Binary asteroid

About 15% of near-Earth asteroids are binaries.

We've all seen the films where an asteroid hurtles towards our planet, threatening civilisation.

What's less well known is that menacing space rocks sometimes come in twos.

Researchers have outlined some of the best evidence yet for a double space impact, where an asteroid and its moon apparently struck Earth in tandem.

Using tiny, plankton-like fossils, they established that neighbouring craters in Sweden are the same age - 458 million years old.

Details of the work were presented at the 45th Lunar and Planetary Science Conference in The Woodlands, Texas, and the findings are to be published in the Meteoritics and Planetary Science journal.

However, other scientists cautioned that seemingly contemporary craters could have landed weeks, months or even years apart.

Continue reading the main story
Proposed double impact craters

Clearwater East and West (Canada): 26km/36km diameter, 290 million years old
Kamensk and Gusev (Russia): 25km/3km diameter, 49 million years old
Ries and Steinheim (Germany): 25km/3.8km, 14.5 or 15 million years old
A handful of possible double impacts (or doublets) are already known on Earth, but Dr Jens Ormo says there are disputes over the precision of dates assigned to these craters.

"Double impact craters must be of the same age, otherwise they could just be two craters right next to each other," the researcher from the Centre for Astrobiology in Madrid, Spain, told BBC News.

Dr Ormo and his colleagues studied two craters called Lockne and Malingen, which lie about 16km apart in northern Sweden. Measuring about 7.5km wide, Lockne is the bigger of the two structures; Malingen, which lies to the south-west, is about 10 times smaller.

Binary asteroids are thought to form when a so-called "rubble pile" asteroid begins to spin so fast under the influence of sunlight that loose rock is thrown out from the object's equator to form a small moon.

Trilobites
Trilobites were among the most numerous inhabitants of Ordovician seas
Telescope observations suggest that about 15% of near-Earth asteroids are binaries, but the percentage of impact craters on Earth is likely to be smaller.

Only a fraction of the binaries that strike the Earth will have the necessary separation between the asteroid and its moon to produce separate craters (those that are very close together will carve out overlapping structures).

Calculations suggest around 3% of impact craters on Earth should be doublets - a figure that agrees with the number of candidates already identified by researchers.

The unusual geological characteristics of both Lockne and Malingen have been recognised since the first half of the 20th Century. But it took until the mid-1990s for Lockne to be formalised as a terrestrial impact crater.

In the last few years, Dr Ormo has drilled about 145m down into the Malingen structure, through the sediment that fills it, down to crushed rocks known as breccias and deeper, reaching the intact basement rock.

Lab analysis of the breccias revealed the presence of shocked quartz, a form of the quartz mineral that is created under intense pressures and is associated with asteroid strikes.

This area was covered by a shallow sea at the time of the Lockne impact, so marine sediments would have begun to fill in any impact craters immediately after they were created.

One-two punch
Dr Ormo's team set out to date the Malingen structure using tiny fossilised sea creatures called chitinozoans, which are found in sedimentary rocks at the site.

Their method, known as biostratigraphy, allows geologists to assign relative ages to rocks based on the types of fossil creatures found within them.

The results revealed the Malingen structure to be the same age as Lockne - about 458 million years old. This seems to confirm that the area was rocked by a double asteroid strike during the Ordovician Period.

Clearwater East and West
The Clearwater East and West craters are the best known candidates for a double impact
Simulations suggest the asteroid that created Lockne was some 600m in diameter, while the one that carved out Malingen was about 250m. These measurements are somewhat larger than might be suggested by their craters because of the mechanics of impacts into marine environments.

Dr Ormo added that Malingen and Lockne were just the right distance apart to have been created by a binary. As mentioned, if two space rocks are too close, their craters will overlap. But to qualify as a doublet, the craters can't be too far apart, because they will exceed the maximum distance at which an asteroid and its moon can stay bound by gravitational forces.

"The Lockne impactor was big enough to generate what's known as an atmospheric blow-out, where you blow away the atmosphere above the impact site," said Dr Ormo.

This can cause material from the asteroid strike to spread around the globe, as happened during the huge Chicxulub impact thought to have killed off the dinosaurs 66 million years ago.

The Ordovician event wasn't powerful enough for that material to be traced, as it would have been very dilute in the atmosphere. But the impact would have had regional effects; for example, any sea creatures unlucky enough to be swimming nearby would have been instantly vaporised.

Other candidate double impact craters include Clearwater East and West in Quebec, Canada; Kamensk and Gusev in southern Russia; and Ries and Stenheim in southern Germany.

However, other researchers say it is impossible to establish that two craters were made at exactly the same time. They point out that craters could have formed weeks, months, or years apart, and that no geological dating technique is sufficiently accurate to resolve such fine-scale differences.

[email protected]. and follow me on Twitter
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Already in a different thread somewhere, sorry...
 
Watch out, Biggles! (or maybe Dan Dare...)

I haven't yet read all 29 pages so I'm not sure if anyone came up with this idea first.

Asteroids coming at us which we can't detect visually because their approach route is so close to the Sun that they're lost in the solar glare.

Hmmm.

Growing uo I was a devotee of Biggles, (and later graduated to the anti-W.E. Johns, Derek Robinson). A repeated theme in WW1 air combat literature is "watch for the Hun in the sun" - the enemy pilot who deliberately positions his plane between you and the sun's glare, so he can come at you undetected and exploit the blind spot.

Are asteroids learning from the Red Baron?

Maybe this class of planetary body should get names, and not dead dry numbers....

"von Richtofen", perhaps, or "Max Immelmann", or maybe even "Hermann Goering".....
 
As it is possible (with the right equipment) to see details on the surface of the Sun, might it not also be possible to see these asteroids approaching?
 
Re: Watch out, Biggles! (or maybe Dan Dare...)

AgProv said:
I haven't yet read all 29 pages

...

Maybe this class of planetary body should get names, and not dead dry numbers....
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But there are named classes of asteroids (as you'd know if you had read the thread!)

The ones that pass closest to Earth are the Amors, Apollos, and Atens.

I posted about them here:

forteantimes.com/forum/viewt ... 15#1300315
Link is obsolete. The current link is:
https://forums.forteana.org/index.php?threads/asteroids.67457/post-1300315

The Atens are the most dangerous. See my post, or search Wiki and the rest of the web for more detail.
 
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Mythopoeika said:
As it is possible (with the right equipment) to see details on the surface of the Sun, might it not also be possible to see these asteroids approaching?
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The sun is so bright that we have to lose a lot of its light to get a usable image.

But a body approaching us from out of the sun mostly shows us its dark, shadowed side, with only a tiny sliver of its illuminated face visible. So 'dimming down' the solar glare is likely to render the asteroid invisible!

One method that might be used involves the Gaia spacecraft, which has the...
Potential to discover Apohele asteroids with orbits that lie between Earth and the Sun, a region that is difficult for Earth-based telescopes to monitor since this region is only visible in the sky during or near the daytime.

http://en.wikipedia.org/wiki/Gaia_(spacecraft)#Objectives
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But Gaia has so much else to do I don't know how much time it will spend on asteroids...
 
Interesting article here, but for some reason I can't copy any of the text, so the bare naked URL is all I can offer.

http://www.telegraph.co.uk/science/spac ... aster.html

Basically the idea is to station a telescope 'near Venus' so it doesn't have to look sunward for these pesky impactors.

The B612 Foundation is not a US government initiative, but a private enterprise. Big press conference planned for Tuesday.
 
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