I watched PBS' Nova program about Alaskan Dinosaurs that was interesting. It discussed how the Dinosaurs survived the cold climate there, but that is assuming the Earth's axis tilt has never changed.
The leading theory as to what caused the dinosaur extinction is an asteroid strike on the earth. Could a big asteroid strike have caused the earth's axis to change causing more severe winters? Has anybody done any research into this possibility?
That could also have caused a shift in the Earth's axial precession which might have caused the cyclical ice ages. I have also considered the possibility that a big asteroid could have changed the Earth's elliptical orbit around the sun, another possible factor in climate change. Of course, this would depend on the angle of the strike and from what direction it came from, all factors that are unknown to me.
It would be nice to have a good history of asteroid strikes on the Earth. Is there something like that available? What was the last big asteroid strike on earth before the ice ages started?
@Metal-Brain
The asteroid that was a huge factor in the extinction of dinosaurs was about 6 miles across, size of a mountain and that left a crater a couple hundred miles wide, now mostly buried in Yucatan but even with the destruction that one did, like piles of debris 700 feet deep a thousand miles away but it did not do much to change the angle of Earth's tilt. Anything bigger than that would have left even heavier traces and some of similar size has come but hundreds of millions of years ago. It is a matter of the percentage of mass of Earth compared to the mass of a 6 mile wide asteroid, insignificant compared to the mass of Earth.
The leading theory of how the moon came about is about a small planet maybe the size of Mars striking Earth billions of years ago before there was any life on Earth and the debris from that strike did a couple of things, one was making the moon and the other was the core of that planet sinking deep into Earth and combining with Earth's core and the evidence for that being they think our core is too big from theories of planetary development from the nebula cloud that became our solar system.
But other than that there has not been anything big enough to change the angle of tilt directly, any such changes could come about from gravitational interactions with large bodies in our solar system but not direct hits.
A direct hit by something big enough to tilt the planet would have left huge craters visible today unless it hit before our present level of continental drift would account for and that would have been more like a half billion years ago so it would not have had any effect on life forms several hundred million years later.
@sonhouse said" it did not do much to change the angle of Earth's tilt."
@Metal-Brain
The asteroid that was a huge factor in the extinction of dinosaurs was about 6 miles across, size of a mountain and that left a crater a couple hundred miles wide, now mostly buried in Yucatan but even with the destruction that one did, like piles of debris 700 feet deep a thousand miles away but it did not do much to change the angle of Earth's tilt. Anything ...[text shortened]... ion years ago so it would not have had any effect on life forms several hundred million years later.
How do you know that? You do not even know the speed it was traveling at, the angle and from what direction. What was the last big asteroid strike on the earth before the ice ages began?
@Metal-Brain
So you can NEVER just take what I read at face value.
Did you see the part about the difference in mass between a single mountain and the entire planet?
It doesn't matter what we write, we are always wrong and you are going to prove it.
Try looking up the velocity it came it at yourself but that won't happen since you are much more interested in the conspiracy theory of the day than actually learning anything.
The planet with mass somthing like MARS could tilt the Earth but not a mountain.
There were some small asteroids hit about 13,000 years ago but not enough to make much of a change in the extinctions that happened 66 million years ago and that one did not change the tilt of Earth by very much at all.
@Metal-Brain
Definitely a good theory.
An impact big enough could change the earth's axis.
If it hit directly into water/ocean the crater would be filled in by sand eventually.
A hit that caused the planet to go molten would also hide the crater.
The celestial body impact that created our moon sucked all the iron (most of it) out of the moon and it went into the Earth body and that's why the moon doesn't rotate because the iron that is left in the moon is all on one side facing us.
What was left was spun out to space by the rotation of the earth and that explains why the moon is about 2 inches farther away from us every year.
Like water in a balloon. You can't roll it. That explains the remaining iron in the moon. Sort of.
Just a theory but definitely interesting 🤔
@sonhouse saidOr are you suggesting the (scientists) don't know that and I am just speculating? 🤷
@Beowulf
Except for the part they know Earth's core is much bigger than it should be and they think the reason is that planet that whacked Earth drove most of its core into the Earth and the two cores coalesced into one
@sonhouse saidThat is because you don't make any sense. The moon was supposedly created because a really big (some say mars like in size) object hit the earth and the remnants spewed into orbit around the planet and it eventually settled into what is now the moon.
@Metal-Brain
So you can NEVER just take what I read at face value.
Did you see the part about the difference in mass between a single mountain and the entire planet?
It doesn't matter what we write, we are always wrong and you are going to prove it.
Try looking up the velocity it came it at yourself but that won't happen since you are much more interested in the conspira ...[text shortened]... hat happened 66 million years ago and that one did not change the tilt of Earth by very much at all.
That could have been why the earth is tilted on it's axis right there, but nobody knows how much and what subsequent strikes may have had in impact. The angle of such strikes is important to how it affected axis tilt. Theoretically, it could have even changed the rotation of the earth, depending on the angle of the strike. The possibilities are many. Think about it.
Look up Milankovich cycle. An asteroid strike could change all of the 3 if it is big enough. Once again, what was the last big asteroid strike before the ice ages started? If you don't know just say so. I don't know either.
We need a good history of big asteroid strikes on the earth. It shouldn't be all that hard. The craters are still there. I see craters here in Michigan all of the time. One of them is on my property. I know of a bigger one on state land where I pick wild blueberries. I'd bet money there is a meteorite under the surface, but first the trees must be removed. It is not a recent strike.
People talk about asteroid mining, yet they do not even look for them on our planet.
@kewpie saidYes, that is called tidal locking.
From a NASA website:
An enduring myth about the Moon is that it doesn't rotate. While it's true that the Moon keeps the same face to us, this only happens because the Moon rotates at the same rate as its orbital motion, a special case of tidal locking called synchronous rotation.
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@kewpie saidYes. And, during the course of one of the Moon's rotation cycles, we can actually view about 59% of the Moon's surface from Earth.
From a NASA website:
An enduring myth about the Moon is that it doesn't rotate. While it's true that the Moon keeps the same face to us, this only happens because the Moon rotates at the same rate as its orbital motion, a special case of tidal locking called synchronous rotation.