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Mars South Pole: H20!
Random Chaos
Actually Carefully-selected Order in disguise
in Zocalo v2.0
ESA has released that Mars Express has detected water ice at the south pole! It had been thought in the past that the south pole was CO2 ice.
[url]http://www.esa.int/SPECIALS/Mars_Express/SEMYKEX5WRD_0.html[/url]
[url]http://www.esa.int/SPECIALS/Mars_Express/SEMYKEX5WRD_0.html[/url]
Comments
[url=http://www.space.com/scienceastronomy/asteroid_flyby_040318.html]Earth Safe from Ultra-close Asteroid Flyby Today[/url]
That passing distance is almost hit.
[url=http://www.space.com/news/hubble_astronauts_040318.html]Hubble-Fixing Astronaut Calls NASA Decision a 'Huge, Huge Mistake'[/url]
I think Jean-François Clervoy agrees with that.
I got that impression from what he talked about Hubble's service mission.
That passing distance is almost hit.[/B][/QUOTE]
That is scarey!
Great pics of Mars, wow!
:)
[B]Maybe the Martian dust will be moist soon enough :) [/B][/QUOTE]
..........maybe its just my dirty mind:rolleyes:.........
[B]Ah, much better than near miss. That would have been terrible. [/B][/QUOTE]
I would more preferably take a hit from this kind of than typical NEOs.
This small objects can cause only local destruction and explosion power is on same scale with large hydrogen bombs.
Outside 50 km radius you should be pretty safe from worst.
Estimates about size of object which made Barringer crater are from 50 to 100 meters.
These ones are from Tunguska:
[url]http://scienceworld.wolfram.com/astronomy/TunguskaEvent.html[/url]
This one is good:
[url]http://www.psi.edu/projects/siberia/siberia.html[/url]
[QUOTE]Seismic vibrations were recorded by sensitive instruments as much as 1000 km (600 mi) away. At 500 km (300 mi), observers reported "deafening bangs" and a fiery cloud on the horizon. About 170 km (110 mi) from the explosion, the object was seen in the cloudless, daytime sky as a brilliant, sunlike fireball; thunderous noises were heard. At distances around 60 km, people were thrown to the ground or even knocked unconscious; windows were broken and crockery knocked off shelves. Probably the closest observers were some reindeer herders asleep in their tents in several camps about 30 km (20 mi) from the site. They were blown into the air and knocked unconscious; one man was blown into a tree and later died. "Everything around was shrouded in smoke and fog from the burning fallen trees."[/QUOTE][QUOTE][b]60 KM South of Ground Zero[/b]
"I was sitting on the porch of the house at the trading station, looking north. Suddenly in the north...the sky was split in two, and high above the forest the whole northern part of the sky appeared covered with fire. I felt a great heat, as if my shirt had caught fire... At that moment there was a bang in the sky, and a mighty crash... I was thrown twenty feet from the porch and lost consciousness for a moment.... The crash was followed by a noise like stones falling from the sky, or guns firing. The earth trembled.... At the moment when the sky opened, a hot wind, as if from a cannon, blew past the huts from the north. It damaged the onion plants. Later, we found that many panes in the windows had been blown out and the iron hasp in the barn door had been broken."[/QUOTE][QUOTE][b]15 KM from Ground Zero[/B]
Because the object exploded up in the atmosphere, instead of hitting the ground, it left no crater. The effect on the ground was limited to devastation of a large forest area. At ground zero, tree branches were stripped, leaving trunks standing up. But at distances from roughly 3 out to 10 miles, the trees were blown over, lying with tops pointed away from the blast. No one was known to have been this close to the blast. The closest humans were probably herders camped in tents roughly 30 km from ground zero. They related:
"Early in the morning when everyone was asleep in the tent, it was blown up in the air along with its occupants. Some lost consciousness. When they regained consciousness, they heard a great deal of noise and saw the forest burning around them, much of it devastated."
"The ground shook and incredibly prolonged roaring was heard. Everything round about was shrouded in smoke and fog from burning, falling trees. Eventually the noise died away and the wind dropped, but the forest went on burning.[/QUOTE]
I would say that explosion power is greatly underestimated in that last link's page: One megaton thermonuclear bomb can break windows only to an distance around 30km.
And shockwave's power is also inversely proportional to distance's cube.
Typical NEOs with sizes over half kilometer can cause destruction in continental wide scale and disturbances in climate.
[B]But these bigger impacts are much rarer. What I read from one science magazine probability of dieing in cosmic impact is only twofold compared to probability of dieing in airplane accident.[/B]
[B]..........maybe its just my dirty mind:rolleyes:......... [/B][/QUOTE]
LOL! Then I must have a dirty mind too, I just didn't like to say what I was thinking case I shocked anyone too much hehee! Glad I wasn't the only one!
;)
[B]In the new issue of maxim they do a pretty good job at describing an asteriod impact on earth. [/B][/QUOTE]
Well, what it says?
This year's first number of "Tähdet ja Avaruus" had article about impact of ten kilometers wide asteroid.
Well, actually it was about Chixculub impact:
Asteroid cuts huge hole to atmosphere and moment later strikes to ocean and bedrock under it. Hundreds of thousands cubic kilometers of rock vaporizes, melts or is blown away instantly. Part of vaporized material escapes to space before hole in atmosphere closes.
Shockwave causes extremely powerfull earthquakes all around the world and in atmosphere it "flattens" everything to distance of thousand kilometer. (diameter of crater is couple hunder kilometers so shockwave must cause total destruction to huge distances) Explosion also raises huge tsunami with height about one kilometer.
Vaporized material creates huge fireball which spreads to atmosphere. Part of fireball's material rises above atmosphere and rains down in few days all over the world in form of small meteorites. (fireball's heat radiation also burns everything within line of sight) This fiery meteorite shower heats up atmosphere which in turn radiates heat to ground igniting everything which is compustible. Heat also vaporizes one meter layer of water from all oceans and boils couple meters more. Nitrogen and oxygen combines in heated atmosphere causing world wide acid rains.
Ash from world wide fires and dust from impact prevents sun light and heat from getting to surface causing dark and cold ice age. After dust settles carbonoxides produced by fires, methane and water vaporized in impact start extreme greenhouse effect wich in turn raises temperature much higher than it was before impact.
So sounds like fun, doesn't it? :D
[url=http://www.space.com/marsrover/]Opportunity Fails to Exit Crater[/url]
And I liked the "bluberry" stones pic. So round that obviously water was there.
:)