Name your five favorite posters on T&FN

[lonewolf]

on the transistory nature of coastlines and other geographic and geologic features.

Just out of interest, was the meteor that hit the Yucatan really as big as they say? 8-)

Probably, maybe bigger. I wan't there to step off the diameter but I have always been amazed that a meteor of the size estimated could make that big a splash with such catatrospic world wide effect. :?

[paulthefan]

on the transistory nature of coastlines and other geographic and geologic features.

Just out of interest, was the meteor that hit the Yucatan really as big as they say? 8-)

Probably, maybe bigger. I wan't there to step off the diameter but I have always been amazed that a meteor of the size estimated could make that big a splash with such catatrospic world wide effect. :?

consider the energy associated with a simple large boulder, for instance a mere 200M kilogram stone, a speck of dust on the scales of the solar system (look up mass of asteroid Ceres for a comparison). Such a fleck hurling at .0003c equates to more than 300MT, far more than the largest atomic weapon. Consider that the earth is presently hurling at .0001c and you can see that we are not talking about extraordinary speed or mass. The damage would be devastating for a larger asteroid.

[eldrick]

i believe it was due to displacement of dirt ( cinder track to hard of learning )

which shot into the upper atmosphere as dust & stayed there for decades++, obscuring light

killing plants - herbivores - raptors

[lonewolf]

i believe it was due to displacement of dirt ( cinder track to hard of learning )

which shot into the upper atmosphere as dust & stayed there for decades++, obscuring light

killing plants - herbivores - raptors

That is the conventional wisdom, which I do not dispute. My wonderment is how could a 6k diameter meteor create a 100k diameter impact crater (The actual numbers escape me but you get the idea.) and kick up enough dust to blanket the atmosphere for years.

[rasb]

i believe it was due to displacement of dirt ( cinder track to hard of learning )

which shot into the upper atmosphere as dust & stayed there for decades++, obscuring light

killing plants - herbivores - raptors

That is the conventional wisdom, which I do not dispute. My wonderment is how could a 6k diameter meteor create a 100k diameter impact crater (The actual numbers escape me but you get the idea.) and kick up enough dust to blanket the atmosphere for years.

Firstly, lonewolf.....don't speak to us of wonderment. You were there, what happened???
Secondly, I am guessing that the diameter of the meteor ( a 2 dimensional definition) would pale in comparison to the mass + velocity of the galactic projectile, and the associated impact of that event --- 2 milion times the energy created by the largest man-made explosion sounds substantial to me...

[paulthefan]

A meteor estimated to be about the size of a house is believed to have caused this:

http://www.psi.edu/projects/siberia/siberia.html

lots of photos exist of the forest that were brushed down like grass.

This one was a real slow poke relative to the earth's trajectory, nevertheless the shock waves and heat were devastating. Increase the speed of impact by an order of magnitude and you have something unimaginably horrible.

[lonewolf]

yeah, I know, but big numbers befuddle me.

[guru]

Biggest current threat out there. Looks like we have 800 years to figure out what we're going to do.

http://tinyurl.com/b2ak8f

http://neo.jpl.nasa.gov/1950da/

[lonewolf]

Biggest current threat out there. Looks like we have 800 years to figure out what we're going to do.

http://tinyurl.com/b2ak8f

http://neo.jpl.nasa.gov/1950da/

Relax. It is actually 871 years and 9 days.

[bad hammy]

Relax. It is actually 871 years and 9 days.

Thanks - I was worried there for a minute.

[paulthefan]

Relax. It is actually 871 years and 9 days.

Thanks - I was worried there for a minute.

let the apes worry about that:
http://www.imdb.com/title/tt0063442/
http://www.youtube.com/watch?v=CvR2mCx- ... re=related
http://www.youtube.com/watch?v=Cmw6Jne0tAQ

[dj]

Relax. It is actually 871 years and 9 days.

Thanks - I was worried there for a minute.

Not me, I'm going to worry about it right now.

Get myself cryogenically frozen, hang out with Ted Williams for about 870 years, then come back to go out with the big bang!

[paulthefan]

Not me, I'm going to worry about it right now.

Get myself cryogenically frozen, hang out with Ted Williams for about 870 years, then come back to go out with the big bang!

you dont really expect the custodians of that freezer to treat you and Ted better than they treated Charlton Heston of "get your stinking paws off me you damn dirty ape" fame, do you.

[bambam]

A meteor estimated to be about the size of a house is believed to have caused this:

http://www.psi.edu/projects/siberia/siberia.html

lots of photos exist of the forest that were brushed down like grass.

This one was a real slow poke relative to the earth's trajectory, nevertheless the shock waves and heat were devastating. Increase the speed of impact by an order of magnitude and you have something unimaginably horrible.

Nobody is actually certain what caused the Tunguska Explosion. This is likely my favorite topic outside of sports and shoulders - I've read about 6 books on it. There are multiple conjectures that have been made - meteors is one of them - also comets, nuclear explosion in low-lying atmosphere, a few other crazier ones. But it remains one of the most puzzling events in earth's history, primarily because it occurred in such an unpopulated, obscure area of the globe.

[lonewolf]

it remains one of the most puzzling events in earth's history, primarily because it occurred in such an unpopulated, obscure area of the globe.

Fortunately. Makes you wonder, what are the chances?