Russian meteor: Could it be worst than that? Meteorite in Chelyabinsk, Russia.
Divers from the Russian Ministry of Emergency Situations (MES) could not find any trace of the meteorite that fell on Friday morning, near the Russian city of Chelyabinsk, told Itar-Tass.
They dive over four hours, but to no avail in Lake Chebarkul, about 80 kilometers (50 miles)west of the city, the day after the surface was localized large hole.
Searches were hampered by virtually zero visibility below the surface and more than half a meter (1.5 feet) of mud on the bottom of Chebarkul. Lake was a hypothesis about the alleged location of the fall of the meteorite.
Altogether, more than 24,000 people and 3,500 units of equipment involved in the search for debris from the meteorite. The fact that these have not been found, heightened skepticism among people. Many say that what happened is rather a military operation. A day earlier, the Russian liberal leader Vladimir Zhirinovsky cut that nothing has fallen from space and the U.S. have tested a new weapon.
No increased radiation after the explosion of the meteorite, but scientists warn of the danger of acid rain.
It is estimated that damage from the fall of the meteorite at 1 billion rubles (25 million euros). Over 1,200 people were injured, mainly by flying glass from broken windows in the blast. 50 of the injured are still in hospital.
NASA yesterday estimated that the power of the explosion of the meteorite entering the atmosphere was about 500 kt or 30 times more powerful than the atomic bomb dropped on Hiroshima in 1945
Chelyabinsk is so strong that ...
The meteor exploded over Chelyabinsk Russian blogosphere. Social networks were filled with humorous interpretations of what happened under the motto Chelyabinsk is so strong that .... ... Chuck Norris became a citizen of the city, says one of the jokes. Chelyabinsk zinc plant is so strong that you take ore straight from heaven. ' Chelyabinsk subway is so cool that travels underground tunnels without. Residents watched in horror meteorite approaching Chelyabinsk.
There was a teaser macho President Vladimir Putin - a collage he was riding meteorite.
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Huge meteorite crashes to ground in russia! 15.2.2013
More than 700 people have been injured or bruised on Friday, including 159 children, allegedly by breaking glass, falling meteorite in the Chelyabinsk region in the Urals, the Ministry of Interior of Russia and authorities that region.
Most wounds suffered when breaking the windows of his house by the impact. In total, had been damaged in at least six cities in this region, located about 1,500 kilometers east of Moscow.
The fragments of a meteorite fell in many houses and smashed roofs and windows. The nuclear plant in the area has not been affected.
All schools in the region remained closed today, according to Moscow said the person in charge of public health control, Genadi Onishchenko.
According to preliminary data over a hundred people have sought medical care, mostly in cut crystal. No serious injuries, said a spokesman of the ministry told Interfax. He added that police patrols guarding the buildings have suffered damage and the loss of his glasses.
The meteorite fell on Lake Chebarkul, about 80 kilometers west Chelyabinsk, informed the local administration. Seven aircraft and about 20,000 members of civil protection in Chelyabinsk have mobilized in the region to assist the population.
The local governor Mikhail Yurevich interrupted his trip to Moscow. With temperatures of 18 degrees below zero in Chelyabinsk now important sustiutir shattered windows, he said.
In many of the houses Satkí and Chelyabinsk in some buildings (capital of the region of the same name), jumped from the window glasses, said the spokesman. He added that 130 of Chelyabinsk school for injuries, apparently because of the breaking of the glass.
Some media reported that the Urals had dropped a meteor shower. It was not a meteor, but a meteor that disintegrated in the lower layers of the atmosphere, he told the Interfax agency spokeswoman Russian Ministry for Emergency Situations, Elena Smirnij.
The ministry spokesman also reported that the meteorite did not affect radiation levels, which remain within the usual parameters for the region.
The Russian astronomer Sergei Smirnov said the meteorite probably weighed several tons before going off. Some of the fragments that hit the earth could weigh up to a kilo.
A spokesman for the European Space Agency ESA said the fall of this meteorite is a fact unrelated to the arrival of the asteroid DA14 '2012 ', which is scheduled to happen tonight near the ground. It's something else entirely. Their journey and place of a hypothetical impact are others, said the spokesman.
How Do We Protect Earth From Asteroids? Part 1 - Finding Them
We know we live in a cosmic shooting gallery. Who’s got their eyes on the sky, and how will we prevent an asteroid strike if we find a dangerous space rock?
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On the early morning of February 13, 2013, people living in the Chelyabinsk region of Russia awoke to one of the most powerful warnings in recent history. Anyone looking up saw an incredibly bright meteor streak across the sky, brighter than the Sun. Observers said they could even feel the heat of the object as it passed overhead.
Moments later, the shockwave arrived, smashing out windows across a huge region, sending almost 1,500 people to the hospital with various cuts and injuries. It was absolutely amazing that nobody died.
But what was it? According to astronomers, the Chelyabinsk meteor was probably a space rock measuring about 20 meters (or 60 feet across). It struck the Earth’s atmosphere going almost 20 kilometers per second, at such a low angle that it just detonated, raining down debris, but sparing the region the true devastation of this kind of an impact.
The Universe delivered a powerful warning that the Solar System is filled with rocks and debris left over from its formation. And those objects still continue to smash into the Earth.
In fact, one of the most terrifying things about the Chelyabinsk strike is this: the meteor was completely unknown to astronomers before it crashed into the atmosphere. The moment of impact was the moment of discovery.
Today I’m beginning a two part series all about the search for killer asteroids and comets. In part one, we’re going to talk about the risks we face. What kinds of objects are out there, how dangerous are they, and what kinds of observatories and programs are working to find the next impact event.
In part two, we’ll talk about defense. If we do find a potentially dangerous asteroid or comet, what can we do to prevent an impact? We’ll talk about the physics and engineering of moving asteroids, to make the Solar System safer.
It’s not a question of “if” an asteroid will smash into the Earth, it’s a question of “when”. In fact, material from space is impacting our atmosphere all the time. According to NASA, about 100 tonnes of rock and dust gets added to the Earth every day. Once a year, a car-sized chunk of space rock impacts the Earth, exploding as a bright fireball.
A Chelyabinsk-level event is thought to happen once every 60 years or so. In fact, there have been three other recorded events with that kind of energy release in the last century, including the 1908 Tunguska event.
Every 2,000 years or so, an object the size of a football field hits Earth, causing localized destruction. And every few million years, an object comes along that releases so much energy, it would threaten the existence of human civilization.
The problem of course, is that we don’t know when or where these events are going to happen.
And it’s this problem that astronomers are trying to solve first.
Tunguska blast simulation by Sandia lab
3D simulation of a 5 megaton explosion that is initiated (asteroid breaking up due to aerodynamic stress and becoming a super-hot fireball) 12 km above the surface, for an asteroid entering at an angle of 35 degrees above the horizontal. Box dimensions are 40 km wide, 20 km high. Colors indicate speed. The hot fireball does not reach the surface, but descends to an altitude of 5 km before buoyantly rising.
At ground zero, the blast wave comes from directly above, consistent with observations of standing trees at the Tunguska epicenter. Moving away from ground zero, the outward component of blast wind speed quickly picks up and levels all trees radially from zero point. Note how the direct and reflected shockwaves reinforce near the ground (brighter area at the lower left indicating shock strengthening). This phenomenon is known as the Mach stem and further adds to the destruction caused by an airburst.
How Much Destruction Can Asteroids Cause Earth
How dangerous are meteors, comets & asteroids? The collisions of these objects with Earth are basically random events, but still we have some idea how often they happen. Localized destruction happens every couple of hundreds of years and is somewhat equivalent to a hydrogen bomb. Last such event happened in 1908 near Tunguska river in Siberia. The number of casualties depends on the place of impact (the objects of this size usually explode in the air before reaching the ground, just like an atom bomb). If a city is struck, casualties could be close to a million, while Tunguska event had zero to one reported casualty (reports vary). An impact in the ocean would create a tsunami and definitely produce significant destruction on the nearby seaside. These events usually do not leave a crater and typically involve a 100-meter asteroid or comet.
A smaller object (around 20m diameter) struck Chelyabinsk Oblast in Russia and did cause over 1000 injuries. Most injuries occured when the blast destroyed windows and struck onlookers inside buildings who were looking at the fireball. Fortunately, there are no reported deaths from the Chelyabinsk impact.
A regional destruction happens at intervals on the order of 100,000 years, and devastates an area a size of a mid-sized country. One such event we know of is an impact that occurred 700,000 years ago in Southeast Asia. These events usually involve 1 km sized asteroids an leave a craters tens of kilometers across.
A global destruction happens less often than every 10 million years and involves an impact of 10 km asteroid making a 100+ km crater. K-T event, which caused the extinction of dinosaurs and other contemporary creatures falls into this category. The amount of destruction depends on the properties of rock in which the crater is being excavated. Unless acidic chemicals are released into the atmosphere such an impact does not necessarily have to produce a mass extinction. In any case, such an impact today would cause casualties among humans in the billions.
It is highly unlikely that a regional or global destruction would occur anytime soon (next couple of centuries) since we have already discovered most of near Earth asteroids larger than 1 km, and none of them seem to be heading this way. A localized impact has a less than a percent chance to happen in any given year, so the level of risk at any given place or time is also low.
Concerning smaller meteorites that hit the ground, they are a very low hazard and no human was ever reported being killed by a small meteorite (while one person was missing after Tunguska). I heard a story that a dog was killed by a meteorite that fell in 1911 in Nakhla, Egypt, and there were also instances of material damage. Still, traffic, pollution and even lightnings are much more dangerous than small meteorites.
Originally, researchers focused their efforts on the largest asteroids: the objects 2 km (1.2 miles) and above. These are the space rocks that could cause wide scale devastation across the planet, affecting the climate and leading the the deaths of hundreds of millions of people. It was calculated that an individual might have a 1-in-25,000 chance of dying in an asteroid impact.
There are many variables that go into calculating the resulting destruction from an impact. You have to consider the velocity, if it’s a metallic or rocky asteroid, and whether it’s fragmented or not.
What should the response be of national and international emergency management officials to a prediction that a 35 m NEA will strike a populated country a decade in the future? Following current interpretations, we would simply tell people near ground-zero to stay inside and not look directly at the high-altitude explosion. But if objects of that size could cause Tunguska-like damage, we might not only evacuate people for 100 km surrounding ground-zero but we would certainly consider a space mission to move or blow-up the threatening NEA.
Originally, researchers thought that Tunguska level events happened once in 4,000 years, but it might be more common, maybe as often as 1-in-700. And perhaps even smaller, more common, asteroids could still cause destruction on the ground – 1-in-200 years.
If Spaceguard Two Survey gets going, it should locate most of the larger asteroids, but even 50% of the Tunguska-sized impactors. It will even be tracking 1-2 million 30 metre objects.
And if one of those rocks is on a collision course with Earth, governments and space agencies will be able to work out an evacuation or prevention strategy.
Music: Compression by Dhruva Aliman
Гиперлапс Челябинск. Сад Победы
Снято на экшн-камеру Xiaomi Yi интервал 5 сек.
Meteor Crashes Russia Town Damage Video Compilation
Thankfully, we missed the catastrophe! An Asteroid flyby was unaware by many people of the earth...but this meteor came down on Ural in Russia.
Astronomers say an asteroid has whizzed safely past Earth over the Indian Ocean, as injured Russians recovered from a separate meteor's sonic boom over the Ural mountains. Scientists said the two events were unrelated.
Live images from a telescope at the Gingin Observatory in western Australia showed the asteroid looking like a white streak across the black night sky.
It's on its way out, said Paul Chodas of NASA's Near-Earth Object program at the Jet Propulsion Laboratory in California as the asteroid DA14 streaked past, some 27,357 kilometers (23, 230 miles) above the Earth's surface.
Raw footage of asteroid flypast
With the naked eye, it was too small to see, even at its nearest point of land on Sumatra.
Earlier, the US space agency NASA had insisted that a smaller meteoric fireball over Russia on Friday was a completely unrelated spectacle.
The widely-filmed fireball had entered the atmosphere, measuring about 15 meters (16 yards) across before disintegrating, while travelling in the opposition direction, from north to south, said NASA on its website.
The larger Indian Ocean asteroid, put at 45 meters wide, passed over the Earth from south to north, it said.
The European Space Agency said its experts had also determined there was no link between the two objects. Russian Academy of Science astronomer Sergei Barabonov also said there was no evidence that the meteor had been traveling on the same path as the asteroid.
Ural windows shattered
The meteor's super-sonic disintegration 30-50 kilometers (19-31 miles) above central Russia left 1,200 residents including 200 children with injuries, mostly gashes from the glass shards of shattered windows, according to Russian authorities.
One leftover of the meteor punched a hole in the ice of the frozen Cherbakul Lake in the affected Chelyabinsk region, which is a hub of Russia's military and defense industry.
The DA14, which was first spotted by Spanish scientists early last year, is thought to originate from the solar system's asteroid belt situated between the orbits of Mars and Jupiter.
Some occasionally break out of the belt, providing a rare opportunity for viewing, say scientists. -DW
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33. Long-Term Biological Effects of Radiation, Statistics, Radiation Risk
MIT 22.01 Introduction to Nuclear Engineering and Ionizing Radiation, Fall 2016
Instructor: Michael Short
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The longer-term effects of accumulated radiation exposure are shown from the cell to the organism level. Trends in cell division rate are linked to both the various symptoms of radiation poisoning and the relative biological susceptibility of different organs. Sources of our knowledge of the effects on large and small doses of radiation are shown, paying particular attention to our lack of definitive knowledge of the effects of very low doses of radiation.
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Don't Worry About That Asteroid That Might Hit This Year | SciShow News
That asteroid the headlines have been warning people about isn't likely to actually hit us, and scientists might have solved a mystery that could save lives: the relationship between tides and earthquakes.
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Olli's Jealous Gods Tour Video Diary (Part 6/6 - Final Stretch)
Subtitles available in English & Russian! Final part of Olli's video diary from the Jealous Gods Tour.
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Simulation Of An Asteroid hitting Los Angeles HD
Los Angeles get struck by a large meteor and its effects are deminstrated in this short simulated video.
Daniel Scheeres: The Future of Asteroid Exploration (Hayabusa2 and OSIRIS-REx Missions)
2019 Purdue Engineering Distinguished Lecture Series presenter Daniel Scheeres
In this lecture, Scheeres discusses the technical challenges and state of the art of spacecraft operations in the asteroid environment. It will also give an overview of both the Hayabusa2 and OSIRIS-REx missions and discuss the extreme and exciting orbital dynamics environment in which these spacecraft are operating. We will also discuss future areas of research that are motivated by these missions, both in pursuit of new scientific discoveries and of autonomous operations about solar system bodies.
Daniel J. Scheeres is a Distinguished Professor and the A. Richard Seebass Endowed Chair at University of Colorado Boulder
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Faculty Panel with Daniel J. Scheeres
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Known as the “Cradle of Astronauts,” Purdue University's College of Engineering’s long list of pioneers includes Neil Armstrong and Amelia Earhart. Purdue Engineering is among the largest in the United States and includes 13 academic programs and ranked Top 10 nationwide by U.S. News and World Report.
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Fallout from Fukushima Daiichi nuclear power plant - Richard Broinowski
Journalist, author, diplomat and Adjunct Professor from the University of Sydney, Richard Broinowski tells the story of the Fukushima daiichi nuclear power plant disaster. His talk looks back to the development of the Nuclear Village in Japan, including General Electric and the American state's successful efforts to sell nuclear energy to Japan under the auspices of selling them energy self-sufficiency. Richard speaks Japanese, has lived in Japan and made many visits. He has thoroughly researched the incident and subsequent events and impacts. He is confident that Japan has, post-Fukushima, 'turned a corner' and notes that many Japanese prefectures are becoming less inclined to restart reactors in the wake of the Japanese people's diminishing faith in the technology and its various safeguards. Will we see Japan embrace renewable energy production with their famous reputation for innovation and stoicism? What does the Fukushima disaster mean for the future of the nuclear power industry beyond Japanese shores? What of the Australian uranium mining industry, and its commercial viability? Richard Broinowski gave this public lecture in the Hawke Centre at the University of South Australia in February of 2012, ahead of the release of his forthcoming book on the subject.
ZBI Astronautics Space News Division 40ft. Meteorite Explodes near Russia Nuclear Yield 200 Kilotons
[ HAL9000 ZBI Astronautics Space News Division ] ZIGZAG BUREAU OF INVESTIGATION Laboratory's, Super Enhanced : Video of a powerful explosion of a bolide has appeared on the Internet. The explosion occurred when the unknown extra terrestrial body entered the atmosphere over the Bering Sea off the coast of Kamchatka in December of 2018. Scientists just recently learned about the explosion over the Bering Sea
Plus Lawrence Livermore National Laboratory LLNL Atmospheric Nuclear Tests Operation Hardtack-1 - Olive Nuclear Yield 202 Kiloton of TNT.
The trail from the flight of the meteorite was captured on the cameras of US satellite Terra and Japanese satellite Himawari-8.
The unique phenomenon occurred about 217 Miles / 350 kilometers off the coast of the Kamchatka Peninsula, at an altitude of about 16 miles / 26 kilometers. The explosion occurred above an uninhabited area, which explains the absence of eyewitnesses.
meteor fireball
Scientists believe, though, that the bolide was about ten meters in diameter, and was flying at a speed of 32 kilometers per second. The energy of the explosion was 173 kilotons in TNT equivalent, which is ten times the power of a nuclear bomb, which was dropped on Hiroshima. It is believed, however, that the explosion of the Chelyabinsk meteorite was more powerful.
The bolide that exploded over the Bering Sea was most likely a rock from the Ursids meteor shower, which was active from December 17 to 26.
Meteorite Explodes over Russia Nuclear Yield 200 Kilotons.
Geheimnis | Krater zeigt: Ein riesiger Meteorit traf einst Grönland
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[Tags], #nemark, #Deutschland, #Grouml;nland, #Krater, #riesigerMeteorit, #Wissenschaft, #Wissen, #Forschung, #Wissen, #Geschichte, #Wissen, #DasNeuste, #TopStories, Krater, zeigt Ein, riesiger Meteorit, traf, einst Grönland
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Kopenhagen (dpa) – Einen 31 Kilometer breiten Einschlagkrater haben Forscher unter Grönlands Eisdecke entdeckt. Mit einer Fläche größer als Paris sei er einer der 25 größten bekannten Einschlagkrater der Erde. berichtet das Team im Fachjournal „Science Advances“ Noch nie zuvor wurde demnach ein solcher. Krater unter einem der kontinentalen Eisschilde der Erde entdeckt An der Stelle müsse einst ein kilometerbreiter Eisenmeteorit eingeschlagen haben. hieß es von den Forschern um Kurt Kjær vom Zentrum für . GeoGenetics am Naturhistorischen Museum der Universität Kopenhagen. Eine Datierung des unter einem Kilometer Eis liegenden Kraters sei bisher nicht möglich gewesen. Er sei aber außergewöhnlich gut erhalten, aus geologischer Sicht könne er recht jung sein. Möglicherweise sei er sogar erst vor 12.000 Jahren gegen Ende der letzten Kaltzeit entstanden. so Kjær Der Zeitpunkt des Auftreffens sei wesentlich für das Verständnis. wie sich der Einschlag auf das Leben auf der Erde auswirkte. Große Meteoriteneinschläge können das Klima nachhaltig beeinflussen.. Die Umrisse des Kraters unter dem Hiawatha-Gletscher im Norden Grönlands waren erstmals 2015 entdeckt worden. Am äußersten Rand der Eisdecke gab es eine enorme kreisförmige Vertiefung. . Doch die Wissenschaftler waren zunächst nicht sicher, ob es sich wirklich um die Spuren eines Einschlags handelt. Erst als ein Team des Alfred-Wegener-Instituts (AWI) in Bremerhaven das Gebiet vom . Flugzeug aus mit einem leistungsstarken Eisradar kartierte, bestätigte sich die Vermutung . „Das neue Radarsystem der AWI-Forschungsflugzeuge war genau die Art von Instrument. die wir für die Messungen brauchten“, sagte Olaf Eisen, Glaziologe am Alfred-Wegener-Institut . Die Struktur sei genau zu erkennen gewesen. „Ein deutlich kreisrunder Rand. eine zentrale Erhebung, darüber sowohl gestörte als auch ungestörte Eisschichten und basale Trümmer. Alles, was einen Meteoriteneinschlag auszeichnet.“.In den Sommern 2016 und 2017 kehrte das Forscherteam an den Fundort zurück, . um Proben von Sedimenten zu sammeln und die tektonischen Strukturen im Gestein am Fuß des Gletschers zu kartieren. Ein Teil des aus dem Krater gespülten Quarzsandes hatte eben jene Deformationsmerkmale. die auf einen gewaltsamen Aufprall hindeuten“, erklärte Nicolaj Larsen von der Universität Aarhus . Das sei ein schlüssiger Beweis dafür, dass die Vertiefung unter dem Gletscher ein Meteoritenkrater ist. Der Einschlag eines Asteroiden in Nordamerika vor rund 66 Millionen Jahren trug wahrscheinlich maßgeblich zum Aussterben der. Dinosaurier bei Sein Durchmesser liegt bei etwa 180 Kilometern. Einem Anfang des Jahres im Fachblatt. „Current Biology“ vorgestellten Szenario zufolge fegte die Detonation im Umkreis von etwa 1500 Kilometern alle Bäume hinweg. Weitere verschwanden bei Waldbränden weltweit. Der Ausstoß schwefelhaltiger Dämpfe führte wahrscheinlich zu saurem Regen. große Mengen Ruß behinderten die Photosynthese von Pflanzen für Jahre un
A Meteorite hit a House in Uruguay & there was bad Meteorite laundering.
...but what I want to know about is the gelatinous cube.
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story by Phil Plait the Bad Astronomer
bout a hundred tons of meteoric material hits the Earth every day.
Now before you panic, essentially all of it burns up in our atmosphere high above the planet’s surface! The vast majority of all that is made up of very tiny bits of rock, metal, or ice sloughed off of comets or asteroids, usually the size of a grain of sand or smaller. This stuff burns up from 80 – 100 kilometers up, and makes lovely shooting stars for us to ooooh and aaaaah at.
But sometimes the object is a bit bigger. How it behaves depends on the composition, impact speed (generally several dozen kilometers per second), entry angle, and even the structure of the incoming meteoroid (some are riddled with cracks and fall apart easily while others are solid and can penetrate deeper)… but if it’s big enough at least some of it will survive to hit the ground.
In general, unless the original incoming object is more than a few meters across, it will explode due to the literally crushing pressure of its atmospheric dive, crumbling into much smaller pieces. These slow very rapidly, usually in seconds, then free-fall their way to the ground. They reach terminal velocity (a constant speed that balances the pull of gravity and the resistance of the air underneath them) quickly as well, and that depends on their size. [Note: This is such a common question that I wrote an article about it, “Why do asteroids explode high in the atmosphere?”]
The Earth is pretty big, so that daily RDA of a hundred tons of cosmic debris is spread out pretty thinly. The odds of a person or a structure getting hit are pretty long… but the chance isn’t exactly zero.
On September 18, 2015, at around 17:45 UTC, a tiny asteroid entered Earth’s atmosphere above San Carlos, Uruguay. It’s unknown how big it was, but most likely far less than a meter. It broke up as it descended, eventually creating lots of smaller pieces that fell to Earth. One of them, a chunk of rock about 9 centimeters in length, defied the odds. It slammed into a house in San Carlos, piercing the roof; a piece broke off and hit their TV (damaging the screen, because duh), while the main piece hit their bed before finally coming to rest on the floor (which it also damaged).
Wow. Happily, no one was home at the time! Even so, the odds of someone getting hit are of course even smaller; people have a far smaller cross-section than a house*. Good thing, as it was moving at about 90 meters/second (over 300 kilometers per hour). Oof. So this is a very rare meteorite indeed!
A team of meteoriticists analyzed the meteorite and published their results in a recent journal. There were a few eyewitnesses to the bolide (the bright meteor as it passed through our atmosphere) who reported it was as bright as the full Moon — and while these sorts of accounts are notoriously inaccurate, that does fit with it being something relative small (for comparison, the 19-meter Chelyabinsk asteroid impact in 2013 was as bright as the Sun).
The big chunk that hit the house is about 9 x 10 x 6 cm, and has a mass of a little over 700 grams. It’s covered in a dark fusion crust — a thin layer of burned material coating the surface, common in meteorites — and also has many regmaglypts: little scoops out of it that look like someone stuck their thumb in clay. Those form as the meteoroid tumbles as it falls; the heat and pressure carve dimples in it.
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About a hundred tons of meteoric material hits the Earth every day.
Now before you panic, essentially all of it burns up in our atmosphere high above the planet’s surface! The vast majority of all that is made up of very tiny bits of rock, metal, or ice sloughed off of comets or asteroids, usually the size of a grain of sand or smaller. This stuff burns up from 80 – 100 kilometers up, and makes lovely shooting stars for us to ooooh and aaaaah at.
But sometimes the object is a bit bigger. How it behaves depends on the composition, impact speed (generally several dozen kilometers per second), entry angle, and even the structure of the incoming meteoroid (some are riddled with cracks and fall apart easily while others are solid and can penetrate deeper)… but if it’s big enough at least some of it will survive to hit the ground.
In general, unless the original incoming object is more than a few
2015 Isaac Asimov Memorial Debate: Water, Water
Join host and moderator Neil deGrasse Tyson and his panel of experts for a lively discussion about the past, present, and future of water on Earth.
Earth is the only place in our solar system with liquid water on its surface. Even though water makes up only 0.03 percent of the Earth’s total mass, it covers 70 percent of the planet’s surface. Where did this water come from? Why is it mostly in liquid form? How much of it is drinkable and how vulnerable is this valuable resource? Will we ever run out? Will wars of the future be fought over access to it? Will future generations harness water from space? Is water essential to all life in the universe—or just to life on Earth?
#IsaacAsimov #debates #Earth #water #panelists #naturalresources
2015 Asimov Panelists include:
-Heidi Hammel, Planetary Astronomer,Executive Vice President of the Association of Universities for Research in Astronomy
-Tess Russo,Hydrologist,Assistant Professor in the Department of Geosciences at Pennsylvania State University
-Ellen Stofan, Planetary Geologist, Chief Scientist of NASA
-Kathryn Sullivan, Geologist, Under Secretary of Commerce for Oceans and Atmosphere and National Oceanic and Atmospheric Administration Administrator
-Charles Wald, General, U.S. Air Force, Retired; Director and Senior Advisor to the aerospace and defense industry for Deloitte LP
The late Dr. Isaac Asimov, one of the most prolific and influential authors of our time, was a dear friend and supporter of the American Museum of Natural History. In his memory, the Hayden Planetarium is honored to host the annual Isaac Asimov Memorial Debate — generously endowed by relatives, friends, and admirers of Isaac Asimov and his work — bringing the finest minds in the world to the Museum each year to debate pressing questions on the frontier of scientific discovery. Proceeds from ticket sales of the Isaac Asimov Memorial Debates benefit the scientific and educational programs of the Hayden Planetarium.
2017 Isaac Asimov Memorial Debate: De-Extinction
2016 Isaac Asimov Memorial Debate: Is the Universe a Simulation?
2015 Isaac Asimov Memorial Debate: Water, Water
2014 Isaac Asimov Memorial Debate: Selling Space
2013 Isaac Asimov Memorial Debate: The Existence of Nothing
2012 Isaac Asimov Memorial Debate: Faster Than the Speed of Light
2011 Isaac Asimov Memorial Debate: The Theory of Everything
Rose Center Anniversary Isaac Asimov Debate: Is Earth Unique?
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