By Elizabeth Landau, CNN
About 1,000 people have been injured in Russia as the result of a meteor exploding in the air. The energy of the detonation appears to be equivalent to about 300 kilotons of TNT, said Margaret Campbell-Brown of the department of physics and astronomy at the University of Western Ontario.
Meanwhile, an asteroid approached Earth but did not hit it Friday, coming closest at about 2:25 p.m. ET.
You probably have some questions about both of those events, so here's a brief overview:
1. Are these events connected?
The meteor in Russia and the asteroid that passed by on Friday afternoon are "completely unrelated," according to NASA. The trajectory of the meteor differs substantially from that of asteroid 2012 DA14, NASA said.
Estimates on the meteor's size are preliminary, but it appeared to be about one-third the size of 2012 DA14.
The term "asteroid" can also be used to describe the rock that exploded over Russia, according to the European Space Agency and NASA, although it was a relatively small one.
2. What's the difference between an asteroid and a meteorite and other space rocks?
According to NASA, here’s how you tell what kind of object is falling from the sky:
Asteroids are relatively small, inactive rocky bodies that orbit the sun.
Comets are also relatively small and have ice on them that can vaporize in sunlight. This process forms an atmosphere and dust and gas; you might also see a “tail’ of dust or gas.
Meteoroids are small particles from comets or asteroids, orbiting the sun.
Meteors are meteoroids that enter the Earth’s atmosphere and vaporize, also known as shooting stars.
Meteorites are meteoroids that actually land on the Earth’s surface. The pieces of the meteor that exploded in Russia are meteorites.
Generally meteorites are smaller than grains of sand and vaporize on passage through the atmosphere. But there are also larger meteorites.
Comets and asteroids are left over from when the solar system formed. There used to be more of them, but over time they’ve collided to form major planets, or they've got booted from the inner solar system to the Oort cloud or have been ejected from the solar system entirely.
3. Why didn't we see the Russian meteor coming?
Only one space rock that impacted the planet has ever been observed before it hit the Earth, Campbell-Brown said.
That's because objects that do hit the Earth tend to be smaller, and it's too hard to see them. The one sighting before impact happened in 2008, a day before a meteor exploded over Sudan.
Current estimates suggest that the Russian meteor was about 15 meters (49 feet) across, which is too small for telescopic surveys.
"Unfortunately the objects of this size have to be very close to Earth for us to be able to see them at all," Campbell-Brown said.
The asteroid that approached Earth Friday, which NASA has been tracking, is about 45 meters long, which is relatively small for an asteroid.
4. How does this compare to other Earth impacts?
The Earth picks up tons of meteoric debris every day, but big pieces are fairly uncommon, said David Dundee, astronomer at Tellus Science Museum in Cartersville, Georgia.
An object the size of the Russian meteor comes in about once every 50 years, but none has been recorded since 1908, when an asteroid exploded and leveled trees over an area of 820 square miles - about two-thirds the size of Rhode Island - in Tunguska, Russia.
"This is the largest event that we know of that's happened since Tunguska," Campbell-Brown said.
The Tunguska event did not leave a crater. If there are craters as a result of Friday's meteor, they would be very small, resulting from the debris from the midair explosion.
"It's unfortunate that this occurred over a populated area," Campbell-Brown said. Over a desert or ocean, it would have done very little damage.
This is much smaller than the event thought to have wiped out the dinosaur population, she said.
The meteor was moving through space at about 33,000 miles per hour. When it suddenly decelerated above Russia, the energy was converted into heat and sound, which resulted in a shock wave of energy and a sonic boom, Dundee said.
About three years ago, a woman in Cartersville, Georgia, discovered a baseball-sized meteorite in her home, which had flown straight through the roof. It is now at the Tellus Museum, Dundee said.
5. Why shouldn't you touch a meteorite?
As a meteor comes through the atmosphere, it gets very hot, but this thin hot layer quickly cools off. When you find it on the ground, a meteorite is generally acclimated to ambient temperature.
"We advise people not to touch things with their hands because we like to look for trace elements in the meteorites, and if you touch it in your hand, you've contaminated it," Campbell-Brown said.
Meteorites are probably not more radioactive than Earth rocks, and the minerals inside aren't toxic, she said. The biggest reason to not touch them is to preserve the scientific status.
Did you see the meteor? Share your images with CNN iReport.
Undeniably imagine that which you said. Your favorite reason seemed to be at the net the simplest thing to have in mind of. I say to you, I definitely get annoyed while people think about concerns that they just do not recognise about. You managed to hit the nail upon the highest and defined out the entire thing with no need side effect , other folks can take a signal. Will probably be back to get more. Thanks
I wish CNN would check their figures.
Altogether, more than 4,000 buildings, mostly apartment blocks, were damaged and 200,000 square kilometers (77,220 square miles) of glass were broken,
this is 26.4 million SF times 77= over 2 billion SF of broken glass. LOL
Editing appears to be a lost science. I think what they meant was that windows were broken across X sq km, but it does appear that they're trying to measure the area of the broken glass itself.
It's incredibly illogical to believe that the meteor that hit Russia and the large asteroid passing by are unrelated.. If the scientists think about it - they will research this to understand how the asteroid and meteorite "events" were related. Too big a coincidence.I am relieved to see that others feel this way. When I say this, people look at me like I'm crazy. I've never been given to conspiracy theories but it seems like folks don't want to frighten the public, or just look less omniscient.
"Too big a coincidence."
Meteorites are flying in all directions across the solar system. That two would be near the Earth at the same time is actually not only very likely, but a fact most every day. You could probably see half a dozen shooting stars on any given night that you're out in the countryside. Are all those meteors also connected?
In short, that you don't understand how these things work doesn't mean there's a conspiracy to keep vital information out of the public's hands. That's just paranoid delusions.
True, but that doesn't mean they are wrong in their theory, either.
Found the crater from Chelyabinsk's meteorite http://www.youtube.com/watch?v=JWYjDroLOBI
Найдена воронка от падения челябинского метеорита http://youtu.be/JWYjDroLOBI
CNN, you define all the terms, and then in the very next sentence you use the wrong one. Appalling.
"Generally meteorites are smaller than grains of sand and vaporize on passage through the atmosphere."
Those are meteors. Meteorites are found on the ground.
You published here, in #2, "Asteroids are relatively small, inactive rocky bodies that orbit the sun."
That is 100% false concerning the size – they range from 1 foot to 100's of miles across. Go back to public school.
I stopped reading after that huge error.
a hundred miles across is small, relative to our solar system, never mind the milky way galaxy or to the size of the universe.
Do you understand what the term relatively means?
Didn't think so.
You didn't happen to find a disgraced DRAGON in that piece of rock? Per chance?
But if you read the whole story (you did do that, didn't you?), then a) they were on completely different trajectories, and were no more related to one another than two random passenger jets; and b) 100 tons of the stuff falls on Earth every single day! So it isn't like this is some weird coincidence other than it's a bit bigger size than is usually observed (and I say "observed" because there are probably many more like that we never see, on a planet that is 75% open water, and with vast tracts of land uninhabited by humans). And by the way, CNN, we don't live on "the Earth" anymore. It's just "Earth". Do you still say "the Ukraine" too? Actually, our planet should be called Water or Oceania, based on its over-all appearance.
If this asteroid that buzzed around our planet is not connected to the meteorite that hit Russia then I should be blind! Or maybe those at NASA have no proper visual sight over Russian airspace and fails to pick up whats coming into our planet. I thought NASA scientists are bright intellectual beings? Well, they missed this one bigtime!
May be all were so busy watching the Asteroid, this one got through un noticed.
One comment stated what hit Russia was not an asteroid but a meteorite. In confusion i decided to search the difference between the two... Damn, i don't need to decide which is which, they're all but bunch of names and terminologies for the sake of... *scratch my head, science?
It is a meteor once it is burning in the atmosphere.
Google... what is a meteor?
"A small body of matter from outer space that enters the earth's atmosphere, appearing as a streak of light."
It is a sign from God that we are living in the last days are predicted in the Bible. With gay marriage, pedophile priests, we are heading for the depths of depravity. We have been warned.
You are as nutty as a fruitcake.
Better rush to church Maria, and be sure take your 10 yo son with you. The priest has "missed" him recently.
You make depths of depravity sound as if it were a bad thing.
What about the possible meteor that occurred in Cuba? Is that unrelated as well?
Yup. Dozens of these things enter the atmosphere every day. Why do you think they should be related?
And what makes you so sure they are unrelated? How can anyone make this claim without direct evidence? Yes, there are so many small meteors that enter the atmosphere every day. But what are the odds that large meteors will happen to fall around the same time a large asteroid is passing by? Most of the space objects are not tracked. So who can say with certainty that the meteors were not part of a bigger asteroid at some point, and broke off?
Another meteor sighting–in San Francisco today. Check out their local news websites. Also supposedly unrelated to the asteroid flyby.
Again - dozens of these things enter the atmosphere every day. So yes, they are unrelated. It's not part of a cosmic plot. It's simply life. It's just that more people were noticing them on Friday.
One third the diameter is one ninth the cross section and one twenty-seventh the volume?
A = pi x r ^ 2 (cross-sectional area through the equator)
A = 4 x pi x r ^ 2 (surface area of the sphere)
V = 4/3 x pi x r ^ 3 (volume of a sphere)
But when they describe a celestial body as being 1/3 the size of another, they are usually referring to diameter, because that's what matters most when trying to view them. The diameter or cross-sectional area is what is directly observed by telescope.
I definitely think that asteroid 2012DA14 that passed earlier today and the 15m russian meteor is related. I have background in celestial mechanics and astronomy for almost all of my 50+ age. If one studies the geometry of the two objects they are infact completely in parallel, and which leads to the shallow flat orbit entering the atmosphere over western Siberia. The south to north orbit vs. northeast to southwest atmosphere trajectory fits exactly each other considering the time of the day and an orbital inclination of just 10 degrees of the asteroid. This is easy to verify using your desktop globe. Take also into account the 23.5 degrees inclination of the earth's axis. Does this sound hard to imagine, in fact it is not!
"Comets and asteroids are left over from when the solar system formed. There used to be more of them, but over time they’ve collided to form major planets, or they've got booted from the inner solar system to the Oort cloud or have been ejected from the solar system entirely." Really? Fairytales dressed as science. There isn't a single provable fact in that paragraph. Where does your Journalist go for facts? Wikipedia?
Just like everyone who has, do, and will live on this planet, scientist have no idea what really is going on. The are just guessing.
Scientists most of the time only care to observe and conceptualize what must be or must have been base on the very things they just saw then concludes anything and further claim it to be facts.
So the Earth isn't spherical. We guessed at geometry and celestial mechanics and just lucked into landing man on the moon six times. Those cures for various diseases were acts of God. Ad infintum.
Yeah, sciencists – what a bunch of liers, deceivers, and cheats.
This article got wroted poorly.
"They've got booted . . ."
It looks like you failed to use the terms "meteor" and "meteorite" correctly right after you gave their definition.
"This is much smaller than the event thought to have wiped out the dinosaur population, she said." really? I would have never guessed
Haha I was thinking the same thing. Duh!
You have been a participant in the biggest interdimensional cross rip since the Tunguska blast of 1909!
I think you have seen Ghost Busters, far to many times.
No, comma, was, required, in, that, sentence.
The real problem with meteors was displayed when a Russian politician declared that this event was part of an American military test. If a larger meteor, say the one that fortunately passed us by today, were to impact Moscow, in the immediate aftermath it would appear no different than a nuclear explosion. Unless scientists on the scene could quickly alleviate fears and tensions by measuring radiation levels with Geiger counters it could possibly lead to a nuclear war. Imagine the entire human race going extinct because of an overreaction to a meteor hitting the capital, or any large city, of a nuclear armed superpower.
Imagine that Moscow didn't have this thing called radar.
Asteroids are "relatively small"? Compared to what? Some asteroids in the "asteroid belt" proper are giant chunks that are a good fraction of the size of a planet. Vesta is 600 km in diameter, and Ceres is even bigger.
Ceres is big enough to be a Drawf Planet, not an asteroid. But it's still smaller than our moon.
So this is where North Korea's test launch wound up?
Wait a minute?!! Did the meteor hit earth or the did the earth hit the meteor?! Somebody draw a force vector diagram to confirm this!
Meteors don't make contact with the earth – meteorites do
Don't be too sure! The Russian meteor could have once been a part of the asteroid, regardless of the direction and approach. The 10-ton meteor could have been torn from the asteroid at some earlier date by a collision with another object. That collision may have given the torn piece (the Russin meteor) a small sideward velocity component, until the asteroid's gravity stabilized the meteor's separation. This separation may have been thousands of miles apart. As the asteroid approached earth from one side, the meteor could have approached from the opposite side. Earth's gravity would cause the meteor to enter our atmosphere from an opposite direction. Think about it.
If that be the case then shouldn't a large object that has landed on Uranis be called Hemorrhite?
And if they stick to the surface, are they Klingons?
And what if the "meteorite" was actually "something" hitching a ride on this conveniently navigated "asteroid" that was scheduled to pass earth Today? Perhaps I've been watching too many movies? :o)
""We advise people not to touch things with their hands because we like to look for trace elements in the meteorites, and if you touch it in your hand, you've contaminated it," Campbell-Brown said."
Sorry to break it to you, Campbell-Brown, the average person is more interested in how a thing can make them a nice little pile of money than they are in maintaining the purity of a meteorite for science's sake.
One would assume also that the monetary value assessed for a meteorite fragment untouched by human hands would be higher than that which had been contaminated- if that's your concern.
"Meteorites are meteoroids that actually land on the Earth’s surface. The pieces of the meteor that exploded in Russia are meteorites.
Generally meteorites are smaller than grains of sand and vaporize on passage through the atmosphere. But there are also larger meteorites."
Wait... but if they burn up... then they're called... oh, boy!
My five year old could provide more cogent definitions of these celestial bodies. Nice work, Ms. Landau!
+1 to Ben.
Clean up the writing CNN. Embarrassing.
Actually, if it burns up in the atmosphere it is a meteor. Once it hits the ground it is a meteorite.
WOW! That was just sad
Clean up this article! "Relatively small" has no meaning if you apply it to asteroids, meteoroids, and comets, and then later say that meteorites range a whole gamut of sizes. You also contradict your accurate definition of "meteorite." It's a mess.
Instead of spending billions on slow-witted robots crawling around the surface of Mars looking for bugs, let's put our money together and build a space station and ship designed to track these rocks and intercept them before they make a mess of our front yard. This is bigger than NASA. Every country should chip in something (cash please, no goats).
Seriously don't pick up the rock? You know how much it would be worth? Collect it all. That ish is gold from the sky.
Oh Jordy Verrill, you lunkhead!
Eric, you just made my day!
As long as you don't contaminate it. Otherwise its worthless.
You can touch it all you want, just be sure to use a condom. Space herpes, you know.
Sorry, I'm not buying that the two are unrelated. The "direction of travel" referenced here was just the direction that the meteor was traveling in our atmosphere. NASA admits that it could not and did not detect this object in space. It is therefore quite possible that the smaller meteor could have been traveling with the larger asteroid, and then changed trajectory due to a collision just outside our atmosphere, or maybe entered the atmosphere from a different direction because it was orbiting the larger asteroid.
i'm wit you...i thank they lying...like in that movie with the meteorite in space, smaller rocks were moving ahead of the larger rock...
And Hollywood knows a lot more about space than NASA scientists.
How is it possible to be certain the two are unrelated if the smaller object was too small to track. What happens in space stays in space, unless it's recorded... It's pure speculation.
No. It's trajectory through space could be seen when it entered the atmosphere it was in no way similar to the trajectory of the asteroid.
Yep, I am sure it is all one big conspiracy set forth by Obama himself. As usual, he ignored scientific evidence and MADE the meteor travel in a different direction to persuade the people of Russia that this meteor has nothing to do with the asteroid. Notable mention: He would have no personal gain other than a diversionary tactic specifically to get away with offending the British over the Churchill bust and taking the blame for the French invasion of Mali.
Obama....I knew it! Diabolical.
I agree, that is entirely plausible.
I mean a change in trajectory due to impact is plausible, not the mumbo jumbo political junk.
Right very plausable... obama sucks but thats not worth reading lol
Yeah, so a meteor traveling 33,000 mph will not completely change direction (like going from North to South, then suddenly going South to North). That being said, I agree that since both events are occuring on the same day, the likelihood that they are completely unrelated is very small (maybe, the direction of the Russian Meteor is not completely understood, yet).
So, a much smaller rock travelling ahead of the main asteroid, travelling South to North, gets inside the Earth's gravitational pull and is unable to break free again, moving up over the North Pole, descending the entire time, until it finally enters the Earth's atmosphere over Russia, travelling North to South. Of course it is entirely possible, and feasible.
The larger asteroid was not big enough for the smaller meteor to orbit it. The asteroid is 'only' 45m across. Its gravitational field would be negligible. its much smaller than a mountain for example.
but larger than a molehill, right?
Right, I don't buy the NASA explanation. This asteroid isn't clean and by itself, it has it's own debris and satellites that we can't detect by their own words. Earth's gravitational field would probably pull these away from the asteroid but not the asteroid itself.
Jim, It is commendable that you've taken that time to express your opinion about the trajectory of the Russian meteor, however you are inaccurate in your understanding of Newton's laws. The mass and relative motion of these two objects would not produce the "change of direction" you speak of. (collision or not)
There is, most likely, a community college near you which offers 100 level (introductory) Physics and Astronomy classes. You appear to have an interest, so I urge you to get involved in expanding your knowledge with regard to these two disciplines. Good luck to you.
High five, Tom.
Jim, the Russian meteorite was some 12h sooner, and travelling north to south according to footage.
2012 DA14 was coming from the bottom (aiming for Antarctica) and missed us flying over the Indian Ocean (again, some 12h later).
This article says no recorded incident of this size since 1908....however there was a large event in Siberia in 1947
"Generally meteorites are smaller than grains of sand and vaporize on passage through the atmosphere. But there are also larger meteorites, as wide as a few miles."
You define correctly that meteorITES have landed on the earth's surface, so how is it that meteorITES vaporize in the atmosphere? I have also never heard of a meteorITE as wide as a few miles in my lifetime. a METEOR or METEOROID maybe.
the meteorite of 65 million years ago, that wiped out the dinos, that was as big as Mount Everest. over two miles easily.
You understand the meteor theory is still just a theory right.
The rock was two miles wide and you compared it to Mt Everest. Mt Everest is nearly 6 miles high and it's footprint is hundreds of miles across. Make an effort to understand what you're reading before you post.
Currently, astronomers classify any natural object that reaches the Earth's surface as a meteorite, regardless of size.
Thats a very dumb question!
Да все нормас у нас, просто суровые Челябинске дети запускали салют)
@Dima :))))))) LOL
LOL vot razboyniki !! ves mir na nogi podnyali
Я пари, вы не имеете каких-либо больше дней, как это один мой друг, удачи.
Why don't they just dock a camera on the Asteroid. That was a real missed opportunity
Because "they" don't have financial resources to do more than a puny fraction of all the awesome things that could be done. Remember, NASA these days only get 0.5% of the federal budget, and EU does much less than that and the rest of the world can't be bothered either. There are so much more important things humanity must dedicate their resources to, such as making weapons, keeping up with the Kardashians and buying designer jeans.
There will come a day when we regret the dismantling of NASA.
I've been regretting it since the Nixon administration.
I have wondered for quite some time if the bigger asteroids might not be more of a strings of rocks and not just a large singular object. The smaller the object in an asteroid string the less kinetic energy it would have, so they would be the ones most likely to impact the earth when a really big one passes so close! Hope we are not in for a shower of like sized Meteors in the coming days!
This is basically correct. Many meteoroids travel in the same trajectory, such as the Leonids and Perseids. Generally these are fragments from a larger body that will stay relatively close together in the same orbit through inertia and mutual gravitational attraction.
This time, however, today's Russian kaboomer and tonight's DA14 are coming at us from almost the opposite directions.
Could the meteor have been in orbit around the asteroid? If it was in orbit and out ahead of it's direction and coming back toward the rear of the asteroid, then that would account for the opposite direction. If this asteroid has more rocks orbiting it then we could expect the earth's gravity to suck in more. Put your umbrellas up!
No, John. It is not connected to the asteroid at all. If they had ever been gravitationally bound, then they both would approach Earth from the same direction. Objects in the vacuum do not change direction without an outside force; basic physics.
Oops, just saw your replay to John. Thanks for the clarification that they would be approaching in the same direction.
I am in no way educated on this subject, but I do think you raise and interesting question.. It seems like it could be plausible. I found this at space.com:
As asteroids revolve around the Sun in elliptical orbits, they rotate, sometimes tumbling quite erratically. More than 150 asteroids are also known to have a small companion moon, with some having two moons. Binary or double asteroids also exist, in which two asteroids of roughly equal size orbit each other, and triple asteroid systems are known as well. Many asteroids seemingly have been captured by a planet's gravity and become moons — likely candidates include among Mars' moons Phobos and Deimos and most of the distant outer moons of Jupiter, Saturn, Uranus and Neptune.
Although this says they are roughly equal in size and clearly these are not.
Here They come, and the fire on their wings doesn't burn....
NASA says no relation.. but... even though it came from another direction, what are the statistical chances of this happening the same day as a historical asteroid is passing? This Asteroid, once in 40 years and the same day a meteor strike that we have not seen since the 1920s? Roughly 9,000,000:1 this was pure coincidence.
Before today those were the odds. Now it's 1:1! :-)
Your right our Government would never tell us not to be worried if we were all going to die. Besides there's just not room for the rest of us in the congressional bunker anyhow! but don't let that trouble you! We can always catch up with our wife's and kids in the after life?
Exactly. Preposterous to even propose they're entirely unrelated.
Precisely. They could very well be third cousins twice removed.
Are you suggesting some sort of collusion in this, like say the meteoroids getting together and planning it out in advance?
IIt's "Oort" Cloud, not "Oord" Cloud.
Look. The big asteroid hit the smaller meteorite and sent it in the opposite trajectory.
Source: I played Asteroids in the 1980's
that's the best comment I've seen yet
What stands out to me is... they didn't see it coming. We get all these reports about an asteroid weeks before it's to pass near the planet, that they've tracked for a long time, and tell us the chances are slim we'll ever be hit by one. Two days in advance we're nearly impacted by a completely unkown object, and 750 people are injured? I love the irony.
Stupid. This thing was no bigger than a basketball. Scientists have trouble spotting LARGE ones in the vast blackness of space. This was an insignificant player in the solar system.
It was bigger than a basket ball-it is estimated it was about 49 feet across
"Current estimates suggest that the Russian meteor was about 15 meters (49 feet) "
That's a really big basketball!
Hear hear! They should be drought before the courts and jailed for missing this asteroid the same way the Italian Seismologist missed the earthquake. Lock them up!
Right... cause that worked so well for the church during the dark ages. Set scientific discovery back several centuries.
@LK He's talking about a current story where the scientists were going to be jailed because they missed the signs of an earthquake, last year sometime I think.
The object was very likely tracked on radar when it got within geosynchronous orbital distance, but at the speed it was travelling there would not have been any significant advance warning. Most likely it will be seen in the logs. Our space-looking radar is geared towards tracking objects in Earth orbit, not approaching from deep space.The only way we currently can detect an approaching object is with telescopes, and our special little visitor today came from sunward.
Perhaps if we had a network of orbital telescopes and radars for just this purpose... *cough cough*
we're gonna have to make stronger umbrellas
There is a connection! That connection is Earth!
TVDevo "dot" "com" has link to the Live CAM from NASA on today's asteroid flyby.
Should be "Generally METEORS are smaller than..." and "... there are also larger METEORS".
An Asteroid can be the size of Rhode Island.... that's not relatively small. All the things they list they list as "Small or Particles" SO i guess there are no larger flyer pieces of rock.... yea. right.
I want superpowers
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