Which of the following events would have the greatest impact on humanity?

[dmill1220]

Hi Blue Fire!
I thought you might find that link interesting!
I played around with it, and finally got to the point, that the Earth was completely melted and destroyed it was a huge Iron asteroid but moving at the speed of an impactor, or comet typically found completely outside our Solar systems influence. I too was surprised of what it would take to do some major damage.
But I question the mathematics they used to achieve the results considering all the variables involved, I'm amazed that someone was actually capable of such Mathematical Prowess.

Umop, that was an excellent point you brought up!
whats weird is if our sun did go Supernova or red Giant, we wouldn't know it for several minutes, if we were not monitoring it with SOHO. but I think our Sun does not have enough mass to go Supernova. it would probably end up swelling as red giant then turning into planetary Nebula that would send out the biggest mass ejection ever.
I think that this whole Dinosaur extinction by one asteroid impact is now being questioned, and a GRB close by, or or Supernova, or some kind of a cyclic flare up as you mentioned, (X-rays) along with other major geological and Meteorological events probably caused the Previous Major extinctions. as I understand the current theories.
Dennis

[Nokton]

Originally Posted by Blue Fire

Thanks for the link! I played with the variables for some time, but was unable to adjust enough to get a resultant crater anywhere close to my original 10 meter crater example. It appears that either a much larger crater will be formed or non at all. The closest I could get was by using a hard rock asteriod with low atmospheric entry speed and high angle of impact that left of crater field due to the breaking up of the asteroid in the atmosphere.

I was surprised to find that even a 40 meter iron asteroid hitting at 90 degrees would cause a crater between .5 and 1 mile wide with not much damage to people or buildings 30 miles away. Judging from this, I'd say that an asteroid that left only a 10 meter crater "field" wouldn't do much damage to anything or anyone not too terribly close to the 10 meter area of the field except for a bit of wind and some loud noise. Hmmm.... might still get some major attention though especially if in the middle of a major city.

Blue, hi,
Hope you and yours OK my friend.
Think you missed a point :-), tectonic plate activity here on earth.
One super volcano could put the earth into deep freeze for decades,
wipe out vegetation and life around most of the globe. Happened before
and overdue now. We may, am sure, develop a response to an asteroid,
but a super volcano, I think not. You will understand my drift Blue...
Nokton.

[Blue Fire]

Originally Posted by Nokton

Blue, hi,
Hope you and yours OK my friend.
Think you missed a point :-), tectonic plate activity here on earth.
One super volcano could put the earth into deep freeze for decades,
wipe out vegetation and life around most of the globe. Happened before
and overdue now. We may, am sure, develop a response to an asteroid,
but a super volcano, I think not. You will understand my drift Blue...
Nokton.

Indeed I do get your drift! There is no question that a super volcano would get Everybody's attention, at least while they were still able to run for their lives! But I was trying to limit the choices to Astronomical events and so even though I'd thought of the super volcano, I didn't think it fit with those Astronomical events that wouldn't wipe us all off the planet. Of course, now I'm questioning whether even some of the choices I gave in the original question are as harmless as I had first thought. Among other possibilites, I considered having a metorite strike in an ocean causing a tsunami. But the space for that actual poll question is limited and I didn't want to get too complicated right off the bat for everyone,... especially Me.

[dmill1220]

Nice Poll!
I hope this has awakened someone!
Dennis

[Nokton]

Originally Posted by Blue Fire

Indeed I do get your drift! There is no question that a super volcano would get Everybody's attention, at least while they were still able to run for their lives! But I was trying to limit the choices to Astronomical events and so even though I'd thought of the super volcano, I didn't think it fit with those Astronomical events that wouldn't wipe us all off the planet. Of course, now I'm questioning whether even some of the choices I gave in the original question are as harmless as I had first thought. Among other possibilites, I considered having a metorite strike in an ocean causing a tsunami. But the space for that actual poll question is limited and I didn't want to get too complicated right off the bat for everyone,... especially Me.

Hi Blue,
First and foremost, my respect to you and all those you love.
Hope you all OK.
Really enjoy posts with you Blue. Just one point Blue with your scenario.
Frequency. The Dinosaurs were dying before the asteroid struck.
65 m years ago, much basalt outflow, you know of what I speak.
The asteroid the final nail in the coffin that ended one species, and
allowed another to take over...
Asteroid impact at this time, is I think, about one in a hundred k years.
Major volcanic eruption around 5 hundred years, or less.
You not wrong in your evaluation of an asteroid striking an ocean and creating a tsumani, our planet is 4 fifths ocean, chances are>>>>?
With respect Blue,
Peter

[Dragon Star]

Personally, I think there are a lot of reasons that Dino's died out, with a collaboration of a few catastrophic disasters...nearly all life was wiped out around that time, and it's likely that not just one event contributed to all of that...probably 2 separate events at close, but separate times. I could be wrong, but so could you.

About striking the oceans, think of this, such a wave would disturb topsoil in a big way, e.g. If I go out to my pond and start pouring in tons and tons of sand, while mixing it up violently, everything in that pond will die.

So then, how was sea life/small water body life (Crocodiles) able to withstand this disturbance so successfully?

[Nokton]

Originally Posted by Dragon Star

Personally, I think there are a lot of reasons that Dino's died out, with a collaboration of a few catastrophic disasters...nearly all life was wiped out around that time, and it's likely that not just one event contributed to all of that...probably 2 separate events at close, but separate times. I could be wrong, but so could you.

About striking the oceans, think of this, such a wave would disturb topsoil in a big way, e.g. If I go out to my pond and start pouring in tons and tons of sand, while mixing it up violently, everything in that pond will die.

So then, how was sea life/small water body life (Crocodiles) able to withstand this disturbance so successfully?

Dragon, my dear friend. So enjoy converse with you.
think upon a crocodiles metabolism, one meal a year suffices.
And no my friend, everthing in your pond not die by your action,
rather new life to cope with what you did would evolve. Nature always
finds a way. It is a progamme built in to the genetic code of life.
That we are not at liberty, through dogma or religion, to explore it
further, just says what we are at. How can we advance further if we
so much constrained by our past, or present, beliefs and mores?
Dragon, am so close now to understanding.
Nokton

[Blue Fire]

Originally Posted by Dragon Star

[snip]
About striking the oceans, think of this, such a wave would disturb topsoil in a big way, e.g. If I go out to my pond and start pouring in tons and tons of sand, while mixing it up violently, everything in that pond will die.

So then, how was sea life/small water body life (Crocodiles) able to withstand this disturbance so successfully?

Interesting point! Do we know (or think) that the so called dino-killer asteroid we theorize that struck off the Yucatan peninsula actually hit water back then, or was the area of impact all land at the time?

[Dragon Star]

That is exactly what I was thinking, so I did a bit of looking on Wiki...

Link

In recent years, several other craters of around the same age as Chicxulub have been discovered, all between latitudes 20°N and 70°N. Examples include the Silverpit crater in the United Kingdom, and the Boltysh crater in Ukraine, both much smaller than Chicxulub but likely to have been caused by objects many tens of metres across striking the earth. This has led to the hypothesis that the Chicxulub impact may have been only one of several impacts that happened all at the same time.

Suggesting that it was indeed a multiple impact that was the cause of KT.

But...

The impact caused giant tsunamis in all directions, which hit the Caribbean island of Cuba especially hard. The emission of dust and particles caused environmental changes close to a nuclear winter, during which the surface of the Earth was totally covered by a cloud of dust for several years.

Then again, perhaps I'm not onto anything, perhaps only the closest areas were affected in the way I describe...but it seems strange to me that oceanic life didn't suffer as much as I would expect.

[Nokton]

Originally Posted by Blue Fire

Interesting point! Do we know (or think) that the so called dino-killer asteroid we theorize that struck off the Yucatan peninsula actually hit water back then, or was the area of impact all land at the time?

Blue,
Interesting conjecture my friend, always thought about the scenarios
of subseqeuent events of the strike, why so much hot debris scattered
around causing forest fires et al? My conclusion, only if the point of impact dry at that time. So much water as evidenced in our time Blue,
would have cooled the ejection, your thoughts please, enjoy converse
with you.
Peter