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Closest Asteroid Yet Flies Past Earth
lmcl writes "New Scientist reports that an asteroid about the size of a small house passed just 88,000 kilometres from the Earth by on Saturday 27 September - the closest approach of a natural object ever recorded. Geostationary communication satellites circle the Earth 42,000km from the planet's centre. The asteroid, designated 2003 SQ222, came from inside the Earth's orbit and so was only spotted after it had whizzed by."
a few days ago APOD had posted this picture. If this picture was taken recently, maybe the asteroid and the fireball are related.
The ones that were closer were the ones like the recent one that hit Orissa. This wasn't even the closest one that could do any damage, it was too small to have even survived the atmosphere. That recent one in Wales which was recorded by the skateboarder -- that was about 80,000 kilometers closer.
Sheesh.
Infuriate left and right
Are this just fragments of a much larger object that is heading towards earth?
No.
KFG
Well, in the grand scale of things, asteroids are going to increase dramatically in the next little while. When I say next little while, I mean the next 50 million years.
We're entering a phase where our system is moving back into the galatic disk in our solar system. In fact, we're closer to the middle of the galactic disk now than we have been for about 70 million years.
Think of it this way - as we whip around in the arms of the milky way, we also move up and down in them. I wonder if an attempt at ascii art would help explain...
------+++------ - Milky Way
^- Us
We accually move back and forth from the top of the dash to the bottom of the dash. Comprende? So we're now moving into the more dense part of the disk, so we'll see more asteroids. Coincedence that the last time we were here the dinosaurs mysteriously vanished? I think not.
Now, one the size of a small house could do some decent damage. Assume that a small house is about 15 meters in diameter. An asteroid about 100 meters in diameter hit siberia in 1908 and flattened 2000 Square Miles of forest. These things aint big, but they do good damage.
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...the Grand Teton Fireball of 1972. This was a meteor/asteroid/rock that grazed the atmosphere over Grand Teton National Park. An 8mm movie was made of the object that was estimated from 5 to several 10's of meters. For more info see http://www.maa.mhn.de/Comet/1972.html
Pictures and details here:t m
http://www.birtwhi.demon.co.uk/Gallery2003SQ222.h
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Ehhh, not quite, IIRC. Little rocks are meteoroids while they're floating around in space, meteors while they're in the atmosphere, and meteorites if and when they land. But asteroids are, of course Big Rocks (anyone know what the lower size limit is?) and I don't think that having them enter the Earth's atmosphere is a common enough occurrence for anyone to have come up for different terminology based on where they are in their descent ...
The correlation between ignorance of statistics and using "correlation is not causation" as an argument is close to 1.
Completly random and un-connected events are bound to coincide sometimes.
Much like the Cancer Hot Spots in the US.
Statistically if cancer is totally random you will have hotspots of cancer. And the quantity of so called hotspots matches what is to be expected.
Have you ever rolled doubles twice in a row in Monopoly?
Were you like, How can this not be related?
Wow, sent an e-mail as suggested when clicking on "use classic" banner, and got a fast response that addressed my msg
if said 'big object' is a 'ball of hydrogen which never got quite big enough to ignite' it would be called a brown dwarf (that is what brown dwarfs are!) and as big as jupiter (same size larger mass, denser etc)
2 000/00-206.html
basic facts
and we would have seen it by now!!!
OK
remember geeks, google is your friend!!
see also
http://www1.msfc.nasa.gov/NEWSROOM/news/releases/
and
http://hubblesite.org/newscenter/archive/1995/48/
You can take this tenth planet and stick it where the sun don't shine.
Someday, you're going to die. Get over it.
Also, diverting a large one into an ocean would still cause problems, probably just as bad as it hitting on land.
Actually, a large scale ocean impact is MORE devastating than a land impact. With a land impact you punch a big hole in the ground and throw a bunch of dust into the air. With an ocean strike you get the same, with the added bonus of a steam explosion as the water in the impact area instantly converts to its gaseous form. Remember, steam expands. As it expands up and out from the impact point, it displaces the atmosphere creating a second shockwave capable of devastating regions thousands of miles from the strike zone.
Best impact point: South Pole. Glacial melting may be an issue, but that'll give us time to evacuate and minimize casualties.
Worst impact point: In the ocean just off the coast of any continent. The ocean is shallow enough to allow the meteorite to strike the ground and simulate a ground impact, but deep enough to allow a massive steam explosion.
There is nothing so pathetic as seeing a beautiful young theory roughed up by a tough gang of facts.
Astronomer to lab assistant: "Hmm; it's too close to call. Hand me those calipers, willya?" ;)
Doing my level best to piss off the religious right wing...
We do not know the composition of the "rock" that flattened Tunguska. It very well could have been an asteroid. Most likely it was a small comet, but we simply do not know.
/ pe shtigo.htm
As I stated its unlikely we will ever know. We do not know because it left behind no debris from which to determine its composition and created no crater. This alone is puzzling.
Another "airblast impact" is known that destroyed several hundred square miles of forest in Brazil in 1930 but seems to have left a crater and debris, although this is still being studied.
While this impact has several intersting points of convergence with the Tanguska event it has a number of points of divergence as well.Such as the crater.
http://star.arm.ac.uk/impact-hazard/Brazil.html
The Chicago fire "theory" (hypothesis really, since there is absolutely nothing to back it up) is a very old crackpot "the sky is falling" story. In "theory" it could be possible, but it defies many points of logic and known science.
I might point out that it is common for for there to be many fires across the midwest, even at the same time, under certain conditions, and those conditions prevailed at the time. It is little reported for instance, that Chicago had already had a number of fires that same season and was a tinder box just waiting for the spark to set it off. As was most of the midwest.
There is no reason to suspect a meteor for setting off fires during hot, dry weather which completely dried ponds when no meteoric activity or big explosions in the sky were reported.
Tokyo has burned down a lot too, as have other cities in Japan. That's what happens when you build your houses out of sticks and paper, then heat them with coals in the middle of the living room floor and light them with fire.
http://www.boisestate.edu/history/ncasner/hy210
http://www.badastronomy.com/bad/tv/skyfire.html
KFG
The Sun (and solar system) last crossed the plane of the Galaxy 2 million years ago and we are currently in the thick of the particulate dust which is held near the plane.
However, the sun is presently located about 50 light-years above the central plane of the galaxy and is currently moving away from the plane of the Milky Way at 7km a second. It is estimated that it will take 14 million years for the gravitational pull of the Galaxy to stop our outward motion and begin to bring us back in.
Unless the Solar system is about to dissipate 7km/second worth of velocity and do an about face and the travel at 100 times the speed of light back to the plane, we won't be back there any time soon.
I think what you were trying to describe is the Earth's path through the Solar system. We will be passing back through the path of the ecliptic which is in effect the 'plane' of the Solar system where the majority of small hard rock type objects reside.
This is, of course, at the system level of motion rather than the galactic level.
We are here:-
Approx 28,000ly from galaxy centre on the 'Orion' arm.
Approx 50ly from mean plane of galaxy
Approx speed relative to galaxy centre: 200km a second.
Ripping an new rectum in the fabric of spacetime.
The show said that there was a temperature rise of about 5 degree C, cause unknown possibly Siberian sheild lava flow, and this warmed the seas enough to cause the melt/sublimation of large amounts of Methane Hydrate releasing large amounts of methane causing a greenhouse effect and another 5 degree rise in global temp.
Links and tidbits:
BRITISH SCIENTIST PUTS ODDS FOR APOCALYPSE AT 50-50
"Humans may have come close to extinction about 70,000 years ago... The study suggests that at one point there may have been only 2,000 individuals alive as our species teetered on the brink."
Try to imagine 1000 volcanoes erupting in the same place at the same time.
"The predicted effects of a Yellowstone eruption are the immediate devastation of North America followed by several years of freezing weather for the whole world."
The primary evidence for the Alvarez theory of extinction caused by asteroid impact is the abnormally high concentration of iridium and other siderophiles in the K-T layer :)
You forgot to mention the GIANT ASS craters that line up nicely when you back-date the tectonic plate movements to that period. This research was done at my little university in Canada
Music speeds up when you yawn, but does not change pitch.
For the asteroid hypothesis to prevail someone has to show how a really big rock can just go "poof" when we know that littler ones don't ( such as the one that just struck in India).
A Russian scientist did, however, reproduce a blast pattern identical to the one on the ground by building a scale model of the terrain and sliding a small explosive down a wire. Detonating at different heights/speeds/angles made several different patterns, among them the same "butterfly".
Until someone can generate/model the same blast pattern by some other method, the exploding object theory is good enough for me. BTW, the experiment was repeated for the documentary I watched, so I will give it more weight than an untested theory. I don't like the thought of having to set up all those toothpick "trees" in the clay after each blast!
88,000 kilometers = 54,680.6649 miles
Left 4 Dead Gaming Group - http://www.l4dgg.com
Two reasons for suspecting they originated on Mars:
Martian meteorites come in a range of ages - some as young as a billion years old. By comparison, most meteorites hang out around the 4.6 billion years old mark - the point when small planetary bodies were forming in the Solar System.
For rocks to be much younger than 4.6 billion they have to come from a body that was evolving - that was hot, partially molten and volcanically active. Such a body would have to be big - a planet. Mars is the most obvious candidate, it shows clear signs of tectonism until relatively recently - new rock was being formed on Mars within the last billion years.
The second reason for suspecting these are Martian rocks is so clever it borders on magical. Some meteorites have been analysed in the lab. They contain vesicles - tiny bubbles of gas trapped in the molten rock. When the rock cooled and froze, the gas was trapped.
When these bubbles are cracked open, the gas inside can be analysed. The ratios of the inert gases (gases such as neon, argon and krypton) precisely match the ratios in the Martian atmosphere measured by American and Soviet probes.
I've no idea if the Egyptian dog-killer has been analysed though.
Best wishes,
Mike.
Because you are looking at the sun when you look towards the inside of earth's orbit. All the dim stuff gets washed out in the sun's light.