For those who do not know (which is probably nobody at this point) a very rare event occurred yesterday in Russia, when a large meteor entered the earth’s atmosphere, burning up and producing a massive shock wave as it crashed to earth.
At present, it remains uncertain if any parts of the meteor managed to reach the surface of earth intact or if it was completely vaporized in the upper atmosphere. Reports indicate large portions may have crashed into a frozen lake. The nature of any material that may have reached the surface remains unknown.
Initial reports indicate that the force of the shock wave produced may have been greater than three hundred kilotons. Thankfully, because the meteor’s trajectory kept it mostly over sparsely populated areas and because the explosion happened at a high altitude, the damage to civilization was not nearly as bad as a ground-level blast of similar magnitude would cause. Still, there was moderate damage, including broken windows and even collapsed roofs due to the overpressure generated. Upwards of one thousand people were injured, though most seem to be non life-threatening. Many of the injuries were caused by broken glass. There are unconfirmed reports of a handful of deaths.
The meteor does not seem to be related to the passing of asteroid 2012 DA14, which came within less than 35,000 kilometers of the earth today. The two events are uncanny in their closeness, as both are exceptionally rare. While it is not uncommon for chunks of an asteroid to break off and follow similar orbits, the Russian meteor appears to have come from a completely different trajectory, unrelated in any way to 2012 DA14.
The event has been compared to the Tunguska Event of 1908, although Tunguska was clearly much larger. Additionally, at this early stage, the exact nature of the meteor that struck Russia yesterday has not been fully established. More will be known as scientists analyze information such as videos, damage reports and seismographic data.
The fact that both this incident and the Tunguska event occurred in Russia as also coincidental. They were in completely different parts of the country, and it should be noted that Russia covers almost 1/5 of the land surface of the planet, making it a large target for such events.
There have been other meteor air bursts. Few have been this large, at least in recent history.
However, what makes this event truly unique is that it occurred in an inhabited region in a day and age where video cameras are almost everywhere. The city of Chelyabinsk is not far from where the event occurred. It has a population of more than one million. In years past, such completely unexpected events would be unlikely to be captured on video. Today, however, video cameras and recorders are so common that any inhabited area will have literally thousands of cameras recording at any given time. Security cameras, cameras on vehicle dashboards (now becoming common on some fleet vehicles for liability and security reasons), amateurs taking cell phone videos and webcams all offer the potential to catch such events, even when completely unanticipated.
As a result, we already have a number of truly amazing videos of the event:
Note the shockwave that is evident in many videos, occurring many seconds after the meteor becomes visible.
It’s worth cruising Youtube for more videos. Since this event is still so recent, there are likely to be more first hand videos uploaded in the hours and days to come.
The videos of this event are more than just a spectacular curiosity. With so many high quality videos, taken at known locations, it should be possible to determine the trajectory of the meteor, the altitude at which it exploded and the nature of the event with unprecedented levels of precision.
In 1992, a meteor streaked across the skies of West Virginia. By sheer dumb luck, the fireball occurred during the height of football season, on a Friday night, when many high school teams were playing, and many parents were out with their camcorders to record the games. As a result, sixteen amateur video tapes captured the fireball, allowing scientists to plot its speed and trajectory by reviewing the videos. The quantity and quality of video of the Russian meteor fireball will dwarf the 1992 Peekskill meteor event in both quantity and quality.
There were some early reports that the Russian military “shot down” the meteor with a missile. It’s highly unlikely that they fired any missiles at it, and even if they had, there’s not much that one can do to “shoot down” a meteor like this. It’s already on its way down and no missile is going to be able to stop a giant ball of rock and metal with that much kinetic energy.
Some in the Russian government have also stated that they wish to address what can be done to defend from this type of event. The answer is basically nothing, not that it really is necessary. Events of this type are so exceptionally rare that they are hardly worth worrying about. Even if the meteor was detected just as it began to enter the earth’s atmosphere and a rapid response could be mounted, there is no way to “intercept” it in any meaningful way. The only possible response would be to give warning to the population to take shelter and stand clear of windows. However, given how rare this kind of thing is, it’s questionable whether the cost of some type of warning system could be justified.
It is possible that an object headed toward earth could be deflected from ever reaching the planet, either by a standoff explosion or by applying a force from a rocket or by some other method, such as a solar sail, laser ablation of the surface etc. A variety of such schemes have been suggested for large asteroids, which could threaten mankind. However, an object this small is unlikely to be detected early enough to mount a response. And, again, given the relative danger, it’s hard to justify spending billions on keeping an arsenal of deep-space interceptors on constant alert.
As powerful as these kind of events can be, I really would not spend too much time worrying about it.
This entry was posted on Friday, February 15th, 2013 at 7:37 pm and is filed under Good Science, Misc, Space. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.
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