gadget_lover
Flashaholic
I wonder about the trajectory for the third rock, the one that streaked across the central California sky. Did it match either of the other two?
Daniel
Daniel
Real life Sci-fi 2013
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jtr1962
Flashaholic
Re: (*) Planetesimal'fest
I've had similar thoughts. I've never collided with a car in 34 years of cycling, but it's only because I ride defensively and have cat-like reflexes. I figure if something ever happens, in all likelihood the driver will say it's my fault regardless of the actual turn of events. After all, cyclists in NYC seem to be blamed for everything from hurricanes to bad hair days. The camera will exonerate me. Same thing if a cop stops me for some traffic violation which didn't actually occur (the police, particularly in Manhattan, have been giving lots of cyclists tickets, sometimes even for violations of laws which don't exist). Come to think of it, the situation here in NYC is pretty much like in Russia-lots of bad drivers, corrupt police force. A camera is sounding better all the time.
LEDAdd1ct
Flashlight Enthusiast
Great question, Daniel.
No, it did not. Different times:
"The meteor entered Earth's atmosphere and blew apart over Chelyabinsk at 10:20 p.m. EST on Feb. 14 (03:20:26 GMT on Feb. 15). The meteor briefly outshined the sun during the event, which occurred just hours before a larger space rock — the 150-foot-wide (45 meters) asteroid 2012 DA14 — zoomed by Earth in an extremely close flyby."
vs.
"Asteroid 2012 DA14 approached within 17,200 miles (27,000 kilometers) of Earth Friday, but never posed an impact threat to the planet. The asteroid flyby and Russian meteor explosion had significantly different trajectories, showing that they were completely unrelated events, NASA officials said."
vs.
"Late Friday, another fireball was spotted over the San Francisco Bay Area in California. That event, also unrelated, occurred at about 7:45 p.m. PST (10:45 p.m. EST/0345 Feb. 16 GMT) and lit up the nighttime sky. Aside from the unexpected light show, the fireball over San Francisco had little other effect."
Source
moldyoldy
Flashlight Enthusiast
some data translated and paraphrased from a few German and Russian websites
NASA scientists estimated the Chelyabinsk heavenly body (meteor/meteorite) to be about 15 meters in diameter with a mass of 7000 metric tons. It entered the Earth atmosphere with a speed of about 18 kilometers per second. It blew up at an altitude of about 20-25 Kilometers. The meteor flew over 4 adminstrative areas with a nominal strike area near the village of Satka. The energy released was estimated by NASA to be about 300 Kilotons of TNT. Unfortunately the "airburst" seems to have totally broke up the meteor and finding the small chunks in a heavily populated area will be difficult. As for specific damage, most of the detonation pressure wave was not focused, but there appears to have been some focused pressure waves that severely damaged some buildings <<ie: The Zinc factory>>. Divers have not found any obvious object(s) at/near the bottom of the 7 meter hole in that nearby lake
<<comment: Given the nature of the earth in the Taiga (including bogs), any object could have burrowed quite deep into Taiga or the bottom of the lake.>>
The (Russian) Ministry of Defense claims to have spotted the meteor nearing the Earth with an estimated velocity of 40 kilometers/second and a mass of 10-30 (metric) tons. They thought that it would burn up in the atmosphere and did not sound an alarm. In the first couple days after the meteor entry, there were some 20K Russian soldiers and 3-7 aircraft searching the area around Chelyabinsk and Satka.
By historical comparison,
the iron-meteor that fell on Sikhote-Alin on the East Coast of Russia in 1947 was estimated to be about 100 (metric) tons also detonated and broke apart in the atmosphere but did create many small holes (sic) in the landscape.
Otherwise the famous Tunguska meteor that exploded over the forested Taiga near a tributary of the Jenissei river caused severe damage to the forest and to local inhabitants. The Estonian minerologist Leonid Kulik (different from the Kulikov fame) later conducted an expedition to that remote area and attempted to reconstruct the event based on what he found and from statements by the locals. The locals saw a huge fireball that seemed to tear apart the sky. People were thrown far more than a meter thru the air and suffered broken bones as they fell back to the ground or landed in the tree branches. The hot pressure wave burned their clothing. The earth shook violently. The heat-storm tore apart the tents of the Tungusen. When Professor Kulik reached what appeared to be the epicenter of the event, the trees were burned and knocked down in a semicircle from the epicenter, but the trees at the epicenter were not knocked down, but stripped of all branches and bark and were burned and charred. ie: the pressure wave was directed vertically down. There was no crater. The estimated diameter of the meteor was about 50 meters. All of the eyewitnesses are now deceased.
NASA scientists estimated the Chelyabinsk heavenly body (meteor/meteorite) to be about 15 meters in diameter with a mass of 7000 metric tons. It entered the Earth atmosphere with a speed of about 18 kilometers per second. It blew up at an altitude of about 20-25 Kilometers. The meteor flew over 4 adminstrative areas with a nominal strike area near the village of Satka. The energy released was estimated by NASA to be about 300 Kilotons of TNT. Unfortunately the "airburst" seems to have totally broke up the meteor and finding the small chunks in a heavily populated area will be difficult. As for specific damage, most of the detonation pressure wave was not focused, but there appears to have been some focused pressure waves that severely damaged some buildings <<ie: The Zinc factory>>. Divers have not found any obvious object(s) at/near the bottom of the 7 meter hole in that nearby lake
<<comment: Given the nature of the earth in the Taiga (including bogs), any object could have burrowed quite deep into Taiga or the bottom of the lake.>>
The (Russian) Ministry of Defense claims to have spotted the meteor nearing the Earth with an estimated velocity of 40 kilometers/second and a mass of 10-30 (metric) tons. They thought that it would burn up in the atmosphere and did not sound an alarm. In the first couple days after the meteor entry, there were some 20K Russian soldiers and 3-7 aircraft searching the area around Chelyabinsk and Satka.
By historical comparison,
the iron-meteor that fell on Sikhote-Alin on the East Coast of Russia in 1947 was estimated to be about 100 (metric) tons also detonated and broke apart in the atmosphere but did create many small holes (sic) in the landscape.
Otherwise the famous Tunguska meteor that exploded over the forested Taiga near a tributary of the Jenissei river caused severe damage to the forest and to local inhabitants. The Estonian minerologist Leonid Kulik (different from the Kulikov fame) later conducted an expedition to that remote area and attempted to reconstruct the event based on what he found and from statements by the locals. The locals saw a huge fireball that seemed to tear apart the sky. People were thrown far more than a meter thru the air and suffered broken bones as they fell back to the ground or landed in the tree branches. The hot pressure wave burned their clothing. The earth shook violently. The heat-storm tore apart the tents of the Tungusen. When Professor Kulik reached what appeared to be the epicenter of the event, the trees were burned and knocked down in a semicircle from the epicenter, but the trees at the epicenter were not knocked down, but stripped of all branches and bark and were burned and charred. ie: the pressure wave was directed vertically down. There was no crater. The estimated diameter of the meteor was about 50 meters. All of the eyewitnesses are now deceased.
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moldyoldy
Flashlight Enthusiast
update from a German website:
members of the Russian Akademie of Sciences have found 53 meteor fragments, all a centimeter or less in size and looking like porous black stone. Based on chemical tests, they were conclusively proven to be part of a meteor of the Chondrite class. Content was about 10% iron, sulfite and Chrysolit.
Based on where the pieces were found, the main meteor chunk is believed to be at the bottom of Chebarkul' Lake (озеро Чебаркуль). However the Chebarkul Lake has a 1.5 meter thick mud bottom. Air temperatures at the lake are minus 20C, so further searching with divers was halted. The chances of finding that main chunk are believed to be minimal. Nevertheless, the area around Chebarkul' lake was restricted to scientists only to stop treasure seekers from finding and attempting to sell supposed bits of the meteor for up to 300K Rubles (7500 Euro). The police are progressively hunting down the sellers. Almost 5000 building were damaged with some 1200 people hurt.
NASA scientists estimated the energy released by the explosion to be about 30 times the Atomic Bomb that was dropped on Hiroshima.
members of the Russian Akademie of Sciences have found 53 meteor fragments, all a centimeter or less in size and looking like porous black stone. Based on chemical tests, they were conclusively proven to be part of a meteor of the Chondrite class. Content was about 10% iron, sulfite and Chrysolit.
Based on where the pieces were found, the main meteor chunk is believed to be at the bottom of Chebarkul' Lake (озеро Чебаркуль). However the Chebarkul Lake has a 1.5 meter thick mud bottom. Air temperatures at the lake are minus 20C, so further searching with divers was halted. The chances of finding that main chunk are believed to be minimal. Nevertheless, the area around Chebarkul' lake was restricted to scientists only to stop treasure seekers from finding and attempting to sell supposed bits of the meteor for up to 300K Rubles (7500 Euro). The police are progressively hunting down the sellers. Almost 5000 building were damaged with some 1200 people hurt.
NASA scientists estimated the energy released by the explosion to be about 30 times the Atomic Bomb that was dropped on Hiroshima.
StarHalo
Flashaholic
Re: Why Russians have dashcams:
Works great for preventing insurance fraud, no so much if the driver has anger issues..
Works great for preventing insurance fraud, no so much if the driver has anger issues..
EZO
Flashlight Enthusiast
Re: (*) Planetesimal'fest
I had been tempted to post the following video in response to jtr1962's comment about driving and bicycling in NYC but didn't wanted to stray too far off topic. Then again, since Russian dash cam videos have been such a central part of the unfolding of the story of February 15th's meteor strike perhaps this is not really as off topic as it may seem and StarHalo has provided the perfect segue, especially now that the major news of this event is behind us.
When I came across this video, I thought I might watch a few minutes of its 13 minute run time but as each more jaw dropping scene unfolded I found myself unable to stop watching the whole thing. Jets strafing the highway, tanks crossing one's path, shootings, fights.....you name it, even the cops are drunk. I'll take NYC any day.
I had been tempted to post the following video in response to jtr1962's comment about driving and bicycling in NYC but didn't wanted to stray too far off topic. Then again, since Russian dash cam videos have been such a central part of the unfolding of the story of February 15th's meteor strike perhaps this is not really as off topic as it may seem and StarHalo has provided the perfect segue, especially now that the major news of this event is behind us.
When I came across this video, I thought I might watch a few minutes of its 13 minute run time but as each more jaw dropping scene unfolded I found myself unable to stop watching the whole thing. Jets strafing the highway, tanks crossing one's path, shootings, fights.....you name it, even the cops are drunk. I'll take NYC any day.
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moldyoldy
Flashlight Enthusiast
Re: (*) Planetesimal'fest
EZO & jtr1962: Thank you for those video links and comments! The main topic had pretty much run it's course anyway
One of my daughters intends to do her residency in the NYC area and she also likes to ride bikes. She has worked in NYC before, but not with a bike. Reading about the NYC bicycle riders and their problems should slow her down. and a doctor that we know wants to visit Russia and does not want to be bothered by public transportation -> wants to drive a rental car. Watching these Russian dash-cam videos will be a great disincentive for his intentions. as for me/wife, outside of the video itself, the verbal comments from the Russian drivers at times were simply hilarious - although quite vulgar in language. Our Russian acquaintances had never mentioned those links, probably because that is the life over there. Thanks to both of you!
EZO & jtr1962: Thank you for those video links and comments! The main topic had pretty much run it's course anyway
One of my daughters intends to do her residency in the NYC area and she also likes to ride bikes. She has worked in NYC before, but not with a bike. Reading about the NYC bicycle riders and their problems should slow her down. and a doctor that we know wants to visit Russia and does not want to be bothered by public transportation -> wants to drive a rental car. Watching these Russian dash-cam videos will be a great disincentive for his intentions. as for me/wife, outside of the video itself, the verbal comments from the Russian drivers at times were simply hilarious - although quite vulgar in language. Our Russian acquaintances had never mentioned those links, probably because that is the life over there. Thanks to both of you!
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jtr1962
Flashaholic
Re: (*) Planetesimal'fest
For what it's worth, she'll probably avoid any problems as far as the police go if she doesn't go through red lights or stop signs right in front of them. Nearly every cyclist here treats red lights as yields simply because nearly every block has a traffic light. As far as avoiding problems with motorists, not too hard if you're generally respectful. Don't make quick maneuvers, cut people off, or pass red lights/ stop signs if there's cross traffic. Fact is everyone in NYC is a scofflaw in a big hurry, but we all somehow make it work. You just need to keep a high spatial awareness of everything around you. It's actually quite a bit of fun once you get the hang of it.
EZO
Flashlight Enthusiast
Re: (*) Planetesimal'fest
Just the intonations in some of the voices were pretty funny without knowing what the comments were and one gets the impression that those Russians sure do know how to cuss without even knowing the language! There sure didn't seem to be too many people on bicycles tooling around the Russian streets either. It must be dangerous enough to just to be a motorist.
Just the intonations in some of the voices were pretty funny without knowing what the comments were and one gets the impression that those Russians sure do know how to cuss without even knowing the language! There sure didn't seem to be too many people on bicycles tooling around the Russian streets either. It must be dangerous enough to just to be a motorist.
moldyoldy
Flashlight Enthusiast
moldyoldy
Flashlight Enthusiast
Re: (*) Planetesimal'fest
there were a few relatively good verbal assessments of the driving by other drivers in the process of their failure. In one case of a truck sliding out of control, the comment was something to the effect of: he is straightening it out ... nope, he is losing it.
However most of the time the politest reference to the other driver was to call him a "Blin" or, as translated, "a pancake". Among other unofficial implications, being called a "Blin" refers to the person's intelligence. Otherwise the cruder appelations and commentary would not be acceptable even in the CPF Underground. Russian swearing is much more creative than just 4 letter words!
there were a few relatively good verbal assessments of the driving by other drivers in the process of their failure. In one case of a truck sliding out of control, the comment was something to the effect of: he is straightening it out ... nope, he is losing it.
However most of the time the politest reference to the other driver was to call him a "Blin" or, as translated, "a pancake". Among other unofficial implications, being called a "Blin" refers to the person's intelligence. Otherwise the cruder appelations and commentary would not be acceptable even in the CPF Underground. Russian swearing is much more creative than just 4 letter words!
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jtr1962
Flashaholic
Re: (*) Planetesimal'fest
1) Try to leave a cushion of space around you for the unexpected. It's a given that pedestrians will suddenly appear, cabs will stop and pick up passengers, etc. so it's best to make sure you have some maneuvering room when they do.
2) It's really common for cars to make turns here without using turn signals. Generally, you'll know this in advance if you hear the engine speed slowing down along with the car starting to drift slightly to the right. If you see this, back off a bit because they'll probably cut in front of you to turn. If there's room you can pass them on the left. In fact, in general only pass on the left at intersections. The exception to this is if you're on the left side of a one way street, such as one the protected lanes on First Avenue.
3) Make sure to be extra careful around buses. Bus drivers here are actually pretty aware of cyclists, but they still need to pull into bus stops frequently. Make sure to always pass buses on the left when they're signaling and pulling into a stop.
4) Cars tend to try to "make lights", so don't go the instant a traffic light changes to green. In fact, it's a good idea to check for cross traffic all the time, just in case.
5) Watch out for potholes! Some streets aren't bad, but others are just littered with potholes, ruts, etc.
6) If you're going a long distance up or downtown, the Hudson River Greenway is probably your best bet for most of the trip. It's basically a bicycle expressway running nearly the length of Manhattan. There are some vehicle crossings to get to piers, but generally you won't be dealing with motor vehicles on the greenway. There's also the East River Greenway, but there's a gap.
The nice thing about riding in the city (i.e. Manhattan) is traffic generally is often moving no faster than bicycle speed. Many times it's moving slower. This makes riding pretty safe so long as you keep aware of things around you. In fact, most of my mishaps have been due to potholes or otherwise uneven pavement. BTW, I live in Queens, not Manhattan, so that's where I ride. The main difference between Queens and Manhattan as far as riding goes is the streets in Queens are in worse condition, the motor traffic generally moves faster, and there are a lot less pedestrians.
NYC Cycling Map:
http://www.nyc.gov/html/dot/downloads/pdf/2012_nyc-cycling-map.pdf
You're quite welcome. Here's a few other pointers I picked up from years of riding in the city which you might wish to pass on:Thanks! I copied off your comments in an email to her.
1) Try to leave a cushion of space around you for the unexpected. It's a given that pedestrians will suddenly appear, cabs will stop and pick up passengers, etc. so it's best to make sure you have some maneuvering room when they do.
2) It's really common for cars to make turns here without using turn signals. Generally, you'll know this in advance if you hear the engine speed slowing down along with the car starting to drift slightly to the right. If you see this, back off a bit because they'll probably cut in front of you to turn. If there's room you can pass them on the left. In fact, in general only pass on the left at intersections. The exception to this is if you're on the left side of a one way street, such as one the protected lanes on First Avenue.
3) Make sure to be extra careful around buses. Bus drivers here are actually pretty aware of cyclists, but they still need to pull into bus stops frequently. Make sure to always pass buses on the left when they're signaling and pulling into a stop.
4) Cars tend to try to "make lights", so don't go the instant a traffic light changes to green. In fact, it's a good idea to check for cross traffic all the time, just in case.
5) Watch out for potholes! Some streets aren't bad, but others are just littered with potholes, ruts, etc.
6) If you're going a long distance up or downtown, the Hudson River Greenway is probably your best bet for most of the trip. It's basically a bicycle expressway running nearly the length of Manhattan. There are some vehicle crossings to get to piers, but generally you won't be dealing with motor vehicles on the greenway. There's also the East River Greenway, but there's a gap.
The nice thing about riding in the city (i.e. Manhattan) is traffic generally is often moving no faster than bicycle speed. Many times it's moving slower. This makes riding pretty safe so long as you keep aware of things around you. In fact, most of my mishaps have been due to potholes or otherwise uneven pavement. BTW, I live in Queens, not Manhattan, so that's where I ride. The main difference between Queens and Manhattan as far as riding goes is the streets in Queens are in worse condition, the motor traffic generally moves faster, and there are a lot less pedestrians.
NYC Cycling Map:
http://www.nyc.gov/html/dot/downloads/pdf/2012_nyc-cycling-map.pdf
moldyoldy
Flashlight Enthusiast
Re: (*) Planetesimal'fest
jtr1962: Thanks for the NYC info - also passed on to my daughter. Having ridden the commuter trains from Berkley Heights NJ in to NYC and then walked a lot, even w/o a bike I appreciate the routes with lesser traffic. I agree that nearly every corner has a light, and have observed that many NYC drivers either have their foot in the carburetor on are standing on the brakes. crazy! Driving to minimize fuel consumption is not something they comprehend.
jtr1962: Thanks for the NYC info - also passed on to my daughter. Having ridden the commuter trains from Berkley Heights NJ in to NYC and then walked a lot, even w/o a bike I appreciate the routes with lesser traffic. I agree that nearly every corner has a light, and have observed that many NYC drivers either have their foot in the carburetor on are standing on the brakes. crazy! Driving to minimize fuel consumption is not something they comprehend.
moldyoldy
Flashlight Enthusiast
Re: (*) Planetesimal'fest
Back to the topic - essentially regarding the more violent forces of nature:
A timely find: the third largest meteor crater was just found in SE Australia in the East Warburton Basin. The diameter of the crater was determined to be 200 km, as generated by an estimated 10-30 KM diameter asteroid that impacted some 300 million years ago. It is believed that impact also led to species die-off over a wide area of the earth because of the pulverized rock thrown in to the atmosphere.
By comparison, vulcanism from isolated volcanoes also has had global effects, not just in Pompei.
The largest recorded volcanic explosion occured in 1815 from the volcano Tambora on the Indonesian island of Sumbawa which pulverized some 160 cubic kilometers of rock.
The island of Krakatoa/Krakatau was the scene of the second largest volcanic explosion in recorded history when in 1883 the ocean reached the main magma chamber underneath Krakatoa and generated a Caldera explosion that pulverized some 20 cubic kilometers of rock and accelerated that rock up to 25 KM in to the atmosphere. Some 165 cities and towns were destroyed at the cost of 36000 lives. The dust from the Krakatau volcanic explosion colored the sunsets even in Britain for the next few years. By comparison, Mt. St. Helens in the US pulverized about 1 cubic kilometer of rock.
The third largest volcanic explosion was Mt. Pinatubo which pulverized about 10 cubic kilometers of rock.
All of these represented global effects! However in general, the large asteroid impacts had greater/longer-lasting effects on life on the planet Earth than the volcanic explosions.
Back to the topic - essentially regarding the more violent forces of nature:
A timely find: the third largest meteor crater was just found in SE Australia in the East Warburton Basin. The diameter of the crater was determined to be 200 km, as generated by an estimated 10-30 KM diameter asteroid that impacted some 300 million years ago. It is believed that impact also led to species die-off over a wide area of the earth because of the pulverized rock thrown in to the atmosphere.
By comparison, vulcanism from isolated volcanoes also has had global effects, not just in Pompei.
The largest recorded volcanic explosion occured in 1815 from the volcano Tambora on the Indonesian island of Sumbawa which pulverized some 160 cubic kilometers of rock.
The island of Krakatoa/Krakatau was the scene of the second largest volcanic explosion in recorded history when in 1883 the ocean reached the main magma chamber underneath Krakatoa and generated a Caldera explosion that pulverized some 20 cubic kilometers of rock and accelerated that rock up to 25 KM in to the atmosphere. Some 165 cities and towns were destroyed at the cost of 36000 lives. The dust from the Krakatau volcanic explosion colored the sunsets even in Britain for the next few years. By comparison, Mt. St. Helens in the US pulverized about 1 cubic kilometer of rock.
The third largest volcanic explosion was Mt. Pinatubo which pulverized about 10 cubic kilometers of rock.
All of these represented global effects! However in general, the large asteroid impacts had greater/longer-lasting effects on life on the planet Earth than the volcanic explosions.
Re: (*) Planetesimal'fest
+
I'v always wondered about the formation of the Michigan Basin.
It's formation/explanation is always a bit incomplete.
The incredible size is what scientists can't really explain.
Is it too big to be a collapsed caldera??
An asteroid impact to create something soo large, would have to be from an asteroid roughly the size of Rhode Island
The geologic record of the area has nearly been wiped clean by several glaciations, unfortunately.
_______________ ^ Similar geologic rocks ,, if you look close, you can make out the great lakes..
____ just reference stuff ^
+
I'v always wondered about the formation of the Michigan Basin.
It's formation/explanation is always a bit incomplete.
The incredible size is what scientists can't really explain.
Is it too big to be a collapsed caldera??
An asteroid impact to create something soo large, would have to be from an asteroid roughly the size of Rhode Island
The geologic record of the area has nearly been wiped clean by several glaciations, unfortunately.
_______________ ^ Similar geologic rocks ,, if you look close, you can make out the great lakes..
____ just reference stuff ^
moldyoldy
Flashlight Enthusiast
Re: (*) Planetesimal'fest
Jon Stewart obviously copied out the better Russian dash-cam accident scenes - a funny/sad presentation. yes, Russian society can be rather coarse - because life over there is coarse and raw. minus 20C and colder is normal. East of the Urals, roads are nearly impassable during the spring thaw. The military is well known for many shenanigans that would have US officers courtmartialed.
Ref my comment above about a US doctor wanting to drive in Russia to carry his ski equipment: After watching the video links, he upgraded his vehicle to a 7 passenger van - for two people. He figured that he needed some more crush space.... and he is considering purchasing a small dash-cam just for the trip!
Jon Stewart obviously copied out the better Russian dash-cam accident scenes - a funny/sad presentation. yes, Russian society can be rather coarse - because life over there is coarse and raw. minus 20C and colder is normal. East of the Urals, roads are nearly impassable during the spring thaw. The military is well known for many shenanigans that would have US officers courtmartialed.
Ref my comment above about a US doctor wanting to drive in Russia to carry his ski equipment: After watching the video links, he upgraded his vehicle to a 7 passenger van - for two people. He figured that he needed some more crush space.... and he is considering purchasing a small dash-cam just for the trip!
moldyoldy
Flashlight Enthusiast
Re: (*) Planetesimal'fest
Ref the Michigan caldera post by Orbital above: How does this basin size compare to the Yellowstone super volcanoe slumbering away for now? The vulcanologists wax eloquent when they speculate on the size of a Caldera explosion from the Yellowstone magma chamber. I do agree that something the size of the Michigan basin is probably an old meteor strike. The astrophysicists have repeatedly commented that the sky in the vicinity of the Earth is relatively calm in the A.D. or CE era. There is plenty of documentation in stone that the sky was not very calm going backwards from the BC/AD transition. Read any of the several works from Velikovsky if you need some more convincing...
Ref the Michigan caldera post by Orbital above: How does this basin size compare to the Yellowstone super volcanoe slumbering away for now? The vulcanologists wax eloquent when they speculate on the size of a Caldera explosion from the Yellowstone magma chamber. I do agree that something the size of the Michigan basin is probably an old meteor strike. The astrophysicists have repeatedly commented that the sky in the vicinity of the Earth is relatively calm in the A.D. or CE era. There is plenty of documentation in stone that the sky was not very calm going backwards from the BC/AD transition. Read any of the several works from Velikovsky if you need some more convincing...
