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Subscribe to RSSDozens were hospitalized and nearly 1,000 residents suffered minor injuries from fallen debris and the impact of the meteor's powerful landing. NBC's Tom Costello reports.
What exactly fell on Russia's Chelyabinsk region on Friday? Was it an asteroid, meteor, meteoroid, meteorite or fireball? You could make a case for "any of the above," depending on your definitions and the precise part of the phenomenon you're trying to describe.
The Chelyabinsk incident is the biggest known cosmic impact since another Russian blast that occurred a century ago, the Tunguska incident of 1908. There's good reason for that notoreity: Hundreds of injuries were reported. NASA estimated that the energy released by the Chelyabinsk impact amounted to 300 kilotons of TNT, which suggests the blast was more than 10 times as powerful as the atom bombs that were dropped on Japan at the end of World War II.
NASA's assessment put the Chelyabinsk object's width at 15 meters (50 feet), and its mass at 7,000 tons. Much of that mass burned up during the object's atmospheric entry at a velocity of 40,000 mph (18 kilometers per second). "The fireball was brighter than the sun," the space agency said in a statement.
Astronomers use different terms to describe cosmic objects of different sizes: When the rock is no wider than a meter (3.3 feet), it's known as a meteoroid. But once you start getting into the 1- to 10-meter range, the term "asteroid" applies. Earlier estimates suggested the Chelyabinsk object was a meteoroid, but the latest assessment would put it in the class of a small asteroid.
Bill Cooke, who heads the Meteoroid Environment Office at NASA's Marshall Space Center, said the object was "a small asteroid or a large meteoroid, depending on how you want to define it."
When pieces of the meteoroid (or asteroid) survive their fiery fall through the atmosphere and hit the surface, those pieces are called meteorites. Russian authorities say a hole in the ice on Chebarkul Lake, near Chelyabinsk, marks a spot where at least one meteorite left its mark. There are already reports of Chelyabinsk meteorites turning up on online auction sites, but those are more likely to be "meteor-wrongs" — rocks wrongly assumed to be meteorites.
Yekaterina Pustynnikova / Chelyabinsk.ru via AP
A huge meteor flares through the skies over Russia's Chelyabinsk region, triggering a powerful shock wave that injured nearly a thousand people, blew out windows and reportedly caused the roof of a factory to collapse.
The term "meteor" refers to the fiery aerial display created by a falling meteoroid or asteroid. Meteors are called fireballs if they shine brighter than the planets in the night sky (magnitude -4), and bolides if the blast is even brighter (around magnitude -14). There's no question that the Chelyabinsk meteor qualifies as a bolide.
Some asteroids are made of iron and nickel, and survive their fall more easily. However, the fact that the Chelyabinsk object appeared to break up into pieces while it was still miles high indicates that it was made of less dense stuff. The stresses of atmospheric entry caused the rock to break apart explosively, creating the midair flash and generating a shock wave. The shock wave produced the loud "bang" that set off car alarms, blew out windows and apparently collapsed the roof of a zinc factory warehouse. Flying glass from all those broken windows caused many of the injuries that were reported.
What about the asteroid flyby?
The Chelyabinsk object streaked through Russian skies just hours before a 150-foot-wide (45-meter-wide) asteroid known as 2012 DA14 was due to make a remarkably close approach, coming within 17,200 miles of Earth's surface. However, the two objects were in dramatically different orbits, and that's one of the factors that led NASA to conclude that the two cosmic events were "not related."
"It's clearly coincidental, but it's a pretty amazing coincidence," said former Apollo astronaut Rusty Schweickart, a co-founder of the B612 Foundation. For years, Schweickart and his colleagues have been trying to raise awareness about the hazards posed by asteroids, and Friday's double dose of cosmic reality certainly serves as a consciousness-raiser.
"It's a torpedo across the bow," Schweickart told NBC News, "and it serves as an indication that these things really do happen."
Objects as small as the Chelyabinsk asteroid are difficult to detect — but the feat is not impossible, given the right circumstances. In 2008, a 2- to 5-meter-wide asteroid known as 2008 TC3 was spotted using the Catalina Sky Survey 1.5-meter telescope in Arizona, 20 hours before its impact in the Sudanese desert. The Chelyabinsk object would have been particularly hard to spot because it came in from the blind spot on Earth's sunlit side.
The Chelyabinsk object is no more, but there are still lots of other space rocks to be found. In 2011, NASA estimated that there are a million potentially hazardous near-Earth asteroids smaller than 100 meters (330 feet). Several organizations — including NASA, the B612 Foundation and Planetary Resources — are working on plans to detect and track more of the threats that are out there. To learn more about those efforts, click on the links below:
- Asteroid activists seek funds for space telescope
- Asteroid mining venture starts with space telescopes
- Asteroids vs. comets: NASA expert assesses threats
Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with Cosmic Log as well as NBCNews.com's other stories about science and space, sign up for the Tech & Science newsletter, delivered to your email in-box every weekday. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for new worlds.
This story was originally published on Fri Feb 15, 2013 1:34 PM EST
Leave a Comment:
Ok, it was an exploding outer-space thingy.
Like the Tunguska Event.
An astro-whatsit that went super-something.
Good thing that bigger thingamajig missed us...
Ya, that would have caused a major kerfuffle!
Anybody check to see if the N. Koreans didn't try to become hero's by shooting down the known asteroid? And then.... um, oops!
Alan...what kind of impact would this asteroid have had had it been nickel and survived the atmospheric descent? Perhaps something on the magnitude of the Meteor Crater impact in Winslow AZ? I believe that one was of equivalent size. Perhaps it could have levelled Chelyabinsk with a direct hit? When visiting Meteor Crater and looking up facts & figures about this impact some 50,000 years ago, it states that a wind roughly 200mph ws generated up to a radius of 20 miles from the site plus vaporizing heat at the site.
Blackbird, this asteroid was a little more than a third the size of the Meteor Crater asteroid, so the crater would not have been as big ... but there would have been a smoking crater and it would have been a far worse day in Chelyabinsk.
Okay, I give up. If we now call meteors "asteroids," based on their size, what do we now call the things whizzing around in the asteroid belt?
This space rock-Russian connection makes me sleep just a little bit better at night. I'm not one to ignore roulette patterns, either.
All jokes aside, the sense of unknown fate provided by the astros is rather unnerving. I'm sure this event triggered many-a subconscious' in respect to.
Which lends to the hypothetical 'Do you really want to know in advance?' And could you blame the Government if they withheld information to a certain doom?
I'd rather not know it was coming. I'm sure I'm in the thin minority, tho.
'Certain' is pretty tough. I gather no extinction events have sterilized the planet yet, far as anyone knows. So yes, they should definitely tell people. You can always tell yourself it's not happening, of course.
If an extinction event is discovered before it hits, whether it be an asteroid or something else, what makes anyone think the government will be the first to know?
The government is a grinding, blinkered bureaucracy focused on the grueling task of running a nation and full of infighting and politicking. They're as surprised as anyone else when disaster strikes.
If someone were to find an asteroid on course to wipe us out, the government would probably find out the same time as everyone else; when they see the news!
Fortunately SF, the scientific community is not as hogtied as the governmental bureaucracy although announcing such an event would ultimately be the governments responsibility. I can't even imagine the ensuing chaos should such a doomsday event happen. Mass hysteria, looting, praying, an enormous migration away from perceived impact site. Perhaps it would be best to keep it a secret although that would be difficult as there are so many backyard astronomers that visual evidence would be hard to conceal from the internet. I don't think its an "if" but when. Fortunately Jupiter has been our goaltender on a few such events. One even hit the moon not long ago possibly the size of the Chelyabinsk asteroid but the moons atmosphere is virtually non existent so the rock didn't disintegrate.
The government would most likely issue a news release admonishing everyone in the affected area to get on line and make their estimated tax payments for the fiscal quarter.
I thought that once enters our atmosphere, it becomes a "thingamajigoroid". Or was it a "thingamajigorite?" I'm still confused...
When in space; Meteoroid.
When moving through the atmosphere: Meteor.
If it survives and makes it to the ground: Meteorite.
However, I've long wondered at what point (and it'll be arbitrary, but that's okay, as long as we all agree on it) of presumably a space rock's mass, we say;
'Less than this is a meteoroid, more than this is an asteroid...'
Some people still lose sleep over the 'brown dwarf > gas giant planet > planet > dwarf planet > asteroid' boundaries, I'm only interested in the line of the next category down.
Thank you for addressing the meteoroid, meteor, meteorite issue.
Almost every report I've seen has used, at least the last two, either interchangeably or incorrectly.
Frank, the most recent proposed standard is that anything wider than a meter could be considered an asteroid, particularly if we find it before it finds us.
Cool. For now, I'll take that.
I almost thought it was a publicity stunt for Bruce Willis to make a sequel to "Armageddeon"
But seriously folks, what was the state of DEFCON and it's Russian equivalent? If a few of these happened simultaneously and itchy trigger fingers were in charge, the only ones commenting on these blogs would be Rad-roaches...
lol... You say "but seriously" and then follow up with a question of whether Russia's defence department can tell the difference between a meteoroid and an ICBM.
Dude, Cold War's over. The Russians are pretty convinced by now that we're not going to nuke them for no apparent reason and vice versa.
Regardless of what they may feel, there is a definite protocol for witnessing large explosions both in our and their armed forces, including coming to a heightened stat of awareness until the relevant facts can be sorted. This may take minutes or hours, but it is still protocol.
"But seriously folks, what was the state of DEFCON and it's Russian equivalent?"
At the moment, I'd say it's at whatever their lowest level is.
But I would not have wanted this to have happened at the height of the Cuban Missile Crisis...!
Thank goodness! No one added cometoids to the confusion :)
This proves the Earth is flat!!! ;-)
Alan, thanks for the tour-de-force through the relevant lexicon. However, as you write:
"Meteors are called fireballs if they shine brighter than the planets in the night sky (magnitude -4), and bolides if the blast is even brighter (around magnitude -14). There's no question that the Chelyabinsk meteor qualifies as a bolide."
wouldn't -14 be dimmer than -4, or do you mean -1.4?
No. When they came up with the magnitude scale, first magnitude was the brightest thing on it, second was dimmer, third was even dimmer and so on. Then they started finding things that were brighter than first magnitude, so they went to zero magnitude, then -1, and -2 and so on. The lower the magnitude number the brighter the object. So -14 is a lot brighter than -4.
OK, that's good to know. Peculiar way of doing things, but certainly not the only odd measurement system.
ARE WE THE NEXT DYNOSAURS?
Why most worry about meteors, while ignoring the most important news humanity is facing: EXTINCTION BY THE END OF THE CENTURY IF WE DO NOTHING ABOUT THIS.
NASA's Chief Jim Hanson
"Imagine a giant asteroid on a direct collision course with Earth.
Every day, due to human activities, earth is warming at the rate of 400,000 four hundred thousand A Atomic bombs 365 DAYS A YEAR.
That is the equivalent of what we face now [with climate change], yet we dither taking no action to avoid the asteroid ” (James Hansen) ( video)
http://www.ted.com/talks/james_hansen_why_i_must_speak_out_about_climate_change.html
This is what is going to end human civilization by the end of the century :
Pres Bill Clinton WARNS: Not addressing population growth and climate change, our fate is human extinction within this century ( video)
http://www.blinkx.com/watch-video/clinton-addresses-climate-change-summit/tZh_B9svAXOthMdqNVJIgw
G Kaplan, MD
WWW.lifewatchgroup.org
"DYNOSAURS"?
Maybe if you spelled Dinosaur correctly I would have made it past the 5th word in your post.
Perhaps. But so many people write such things in all seriousness, it's hard to be sure...
I hate rich beggars and some research beggars. This issue has not hit the news yet there are already guys asking for more funding for asteroid research, asteroid mining and asteroid toilet plug holes! This is crazy.
Cool it people! People have been hurt by this bolide in Russia. Have some sensitivity.
If these Space Cowboys, not all space researchers are like that, continue this window of opportunity to beg for more money...this bolide thing is not going to "look like a big coincidence". People are going to speculate that this bolide in Russia, that struck today hurting a lot of people, was part of the asteroid 2112 DA 14 - caused by some kind of deliberate missile strike to the asteroid"
Do not allow these kinds of speculations by this kind of self serving promotion for more funding now.
Kindly remember people have been hurt by this bolide strike.
Even scientists need to show some sensitivity...rather than asking for more money at this time.
Well really, it has hit the news. And only a crazed loon looking for a conspiracy theory to beat all conspiracy theories would attach his lunacy to the kind of idea you implied (that scientists and the military surreptitiously fired a missile to break off a piece of an asteroid on purpose, to make it look like such a threat to the citizenry that they would gladly pay much more for protection, or research into possible protection).
Trust me, plenty of people are at the loon level level of crazy, and beyond.
They've never heard of Occam's Razor, or the related phrase; 'When you hear hoofbeats, think horses, not zebras.'
Thanks for the follow up Alan with the explanation and vocabulary used,
Beats the heck out of There was a big bang in the sky...
Quite few folks appreciate that, that I know of :o)
I was excited to read and see this news until the guy starting talking about Soviet era housing not being well-built and then it hit me: HOW POLITICALLY-SLANTED and incompatible that comment (and I'd imagine the rest of the clip was but could not be assed to watch) was with the professional vow that journalists take to uphold the highest convention of objective reporting... and as for the better part of the comments in this thread... God help us!
Great T-Shirt on the Russia Meteor Story:
"It's clearly coincidental, but it's a pretty amazing coincidence," said former Apollo astronaut Rusty Schweickart, a co-founder of the B612 Foundation.....
Well, OF COURSE, it is an amazing coincidence. Have you ever seen a coincidence that wasn't amazing?
Sure. Some are just mildly interesting...
My understanding is that the blast which broke all the windows was just the sonic boom resulting from the speed through the atmosphere, not from the breakup of the meteoroid.
Well, yes and no. When it breaks up, there is much more surface area exposed to the airflow, which briefly causes a much more intense boom; basically an explosion.
And that's why simply blowing up (as opposed to deflecting) a seriously big one, isn't enough...
Thanks Eric, that makes sense. I'll only note that there would have been a large shock wave regardless of whether the object fragmented.
No, the terminal flash of a bolide is due to an upsurge in heating, surface area, and the cumulative dose of energy into the thing to cause vaporization. You can see this in the videos of this event, particularly the one that shows the traffic monitor getting blitzed as the light pulse rises in fractions of a second. Like a nuclear weapon, light energy dumped into the air drives compression into the shock wave. For these guys it's visible and perhaps some UV driving things; for the nuke, it's x-ray deposition.
errm... You have quoted a typo - the Russian meteor was around 10 tons, if my memory serves, not the 7,000 you've quoted.
VERY IMPORTANT PRINCIPLE TO UNDERSTAND, EVERYONE!
Please understand that the greater the altitude that the breakup of an asteroid occurs, with the resulting midair flash and shock wave in the sky, the less that any resulting detrimental effect is going to be felt way down here on the surface of the Earth. It even dramatically lessens the possibility of asteroid fragments making it through to the surface of the Earth, especially with any followup strikes to any large remaining pieces of these asteroids or comets. This is why it is so very important for our international community to build a standing arsenal of Deep Space Ballistic Missiles (DSBMs) (just a couple of dozen), which they can use to hit these threatening asteroids or comets before they hit us. I (Rick Carter) urgently implore the international community to build this standing arsenal of DSBMs to protect our planet, before the only alternative is to kiss all of our loved one's goodbye! Once again, please listen before it is too late for mankind here on Earth Thank you, one and all! - Rick Carter
The sensible range of response to asteroid threats is not limited to, and may not even include, this nuclear ballistic missile fleet. It remains to be demonstrated that busting these bad boys up has a comfortably high probability of never making things worse. Once you do it and it goes bad, after all, there's no turning back.
Time is our greatest ally in the enterprise. With time to plan, even just making a big rock fart in the sunshine — preferentially to one side — could save the day.
Asteroid - the object floating in space...meteor - said object once it enters the atmosphere...meteorite - said object if it survives its journey through the atmosphere and a piece of it lands on earth. At least, that's what I was taught.