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View Full Version : If Ceres hit the Earth head on at 40 km/s in the Pacific Oc.

2004-Feb-26, 12:37 AM
Ok, lets say that a gravitational disturbance with Jupiter caused Ceres to come barreling toward us.

What would be the immediate damage, not counting the blocking of sunlight my dust particles, etc.

Is there even a remote change for human survival?

Would any animals larger than a dog survive?

Would any life, including microbes survive?

How far away could a person see this asteroid hit the Earth (it's hitting the middle of the Pacific Ocean)

What would it be like as Ceres entered the atmosphere?

What would be the human reaction if there was indeed an asteroid of this size headed our way?

Thanks for the time for answering my questions. :D

ToSeek
2004-Feb-26, 12:44 AM
For starters, you can go to this site (http://janus.astro.umd.edu/cgi-bin/astro/impact.pl) and enter parameters:

Earth
Rock
933 kilometers
40 kilometers/sec

and see what happens.

2004-Feb-26, 12:49 AM
For starters, you can go to this site and enter parameters:

daver
2004-Feb-26, 12:59 AM
For starters, you can go to this site and enter parameters:
Try this one:
http://janus.astro.umd.edu/astro/impact.html
The link he gave was to the results page.

2004-Feb-26, 01:05 AM
it would release 193471 billion tons of TNT!! wow......and a earthquake of 15.2? how much destruction would that cause?
and how big would the crater from this asteroid be?

xbck1
2004-Feb-26, 01:12 AM
Fropm the results page:

Crater Diameter: 6700.0 km
Crater Depth: 4.2 km

In other words, Earth is toast.

PS: diameter of Earth= ~12,750 kilometers.

2004-Feb-26, 01:29 AM
Crater Diameter: 6700.0 km
Crater Depth: 4.2 km
how could a crater be 6,700 km wide and only 4.2 km deep? the asteroid itself is over 900 km!!! :-?

daver
2004-Feb-26, 01:33 AM
Ok, lets say that a gravitational disturbance with Jupiter caused Ceres to come barreling toward us.

That's about as likely as a magnetic interaction with a refrigerator magnet causing Ceres to come barreling towards us, but I suppose that's not the point.

What would be the immediate damage, not counting the blocking of sunlight my dust particles, etc.

Is there even a remote change for human survival?

Would any animals larger than a dog survive?

See the impact calculator

Would any life, including microbes survive?

Possibly. No surface or ocean life, certainly, but microbes exist in some strange places.

What would it be like as Ceres entered the atmosphere?

Uncomfortable.

Ceres is roughly half the diameter of the moon; it would appear as big as the moon when it's half as far away, and would keep getting bigger. It has maybe 1% the mass of the moon, and tidal effects go as the inverse cube of the distance, so when it's roughly 1/4 as far as the moon (and looks twice as large as the moon) its tides will be equal in strength to the moon's tides. That's maybe 70k km out, so impact would be in maybe another half an hour.

I'll let someone who knows better figure the effect of Ceres on the atmosphere. It's obviously coming in at many multiples of the speed of sound--the air in front will be compressed to incandescence and then some. The radiation should be sufficient to flash anything combustible that it impinges on into flame; since it's slamming into the Pacific, though, that might not be too much.

What would be the human reaction if there was indeed an asteroid of this size headed our way?

About what you'd expect. Looting, rioting, pillaging. Many people would turn to various religions to try to divert the upcoming disaster or to gain a chance at an afterlife if they can't. Since such an event (Ceres being warped out of its orbit by Jupiter) is absolutely impossible according to our current understanding (roughly on par with the moon opening its eyes and grinning at us before it proceeds to amble off arm-in-arm with the sun), many scientists would join them.

daver
2004-Feb-26, 01:39 AM
Crater Diameter: 6700.0 km
Crater Depth: 4.2 km
how could a crater be 6,700 km wide and only 4.2 km deep? the asteroid itself is over 900 km!!! :-?

The page said that the results are approximate; the crater calculations weren't designed to handle such results.

The immediate vicinity is going to be molten, the crust will be breached, magma will flow, the shock may pass through the earth and cause volcanic episodes on the far side of the impact.

AGN Fuel
2004-Feb-26, 02:11 AM
What would be the human reaction if there was indeed an asteroid of this size headed our way?

About what you'd expect. Looting, rioting, pillaging....

'Cats and dogs, living together....' :lol:

(roughly on par with the moon opening its eyes and grinning at us before it proceeds to amble off arm-in-arm with the sun)....

Careful daver. In Rick Sobie's world, that is an imminent event.

Kizarvexis
2004-Feb-26, 05:23 AM
Awhile back there was a thread (click here) (http://www.badastronomy.com/phpBB/viewtopic.php?t=7278) about using a fast moving rock (0.5c) to hit a earth-like planet and the poster wanted to know the damage that would be caused. I googled the following page which will handle higher velocities than the page above.

Asteroid Impact Crater (http://home.att.net/~srschmitt/crater.html)

Kizarvexis

Swift
2004-Feb-26, 01:58 PM
What is this fascination with smaking the Earth with rocks? Looking at all the threads, we could have a forum just on those topics. I guess little boys just like breaking things. I personally follow the Gomez Addams approach and crash my trains together. :D

tofu
2004-Feb-26, 02:54 PM
What is this fascination with smaking the Earth with rocks? Looking at all the threads, we could have a forum just on those topics. I guess little boys just like breaking things. I personally follow the Gomez Addams approach and crash my trains together. :D
IIRC we had about a decade without any bright comets and then we had two, one right after the other, that came out of nowhere so to speak. There was a renewed interest in astronomy in general and NEOs in particular. The media ran out of legitimate, informative stories fairly quickly and began looking around for something new to scare people (because fear = ratings) To their great, almost orgasmic delight they found that many scientists had already written about the probabilities and the effects of impacts and so the media seized on that free data and used it to write apocalyptic visions of the end of the world.

If, back in the '70s a scientist wrote that statistically we seem to have a major impactor every 50K years, that paper would have received little notice. But as the media frenzy picked up, they started going back and finding these articles and writing headlines that read OMG! IT'S BEEN 50,000 YEARS! WE'RE ALL GOING TO DIE!!1!

This all culminated in at least two hollywood movies and more made-for-tv specials than I care to remember.

Comet Shoemaker-Levy 9 only increased the trend toward doomsday reporting. Do you remember any news story that explained how the comet might have been captured by Jupiter, or how long it had been in orbit? Do you think anyone knows what cause it to break up? Nope. But everybody knows it made a big boom on Jupiter and everybody knows we'd be toast if it hit us.

At the same time, technology had improved to the point that it was possible to send probes to asteroids and comets. But in today's climate, it's not possible to report on the NEAR mission without at least a passing reference to what would happen if it hit the Earth.

So to answer your question, as I see it, the fascination with smacking the Earth with rocks comes from constant exposure to popular media and the way it sensationalizes science.

It's similar to what we had with black holes in the '80s. Back then, every TV show about them would address the question "what would happen if the Earth fell into one of these things" complete with sound effects so you'd feel like you were really there.

The sensationalism in reporting on Black Holes seems to have worn off. Maybe something similar will eventually happen with comets and asteroids. Maybe one day it will be possible to report the size and composition of one without going out of your way to describe what would happen if it hit the Earth. Because to be honest, I wasn't really looking forward to reports on the New Horizon mission that told me nothing about the Kupier belt objects other than that it'd be really bad if they hit us.

Diamond
2004-Feb-26, 05:43 PM
The shock wave would go right around the earth and produce massive flood vulcanism from the fracture - result - anyone who escaped the immediate imapct would be poisoned by the gases released. The Earth would go into a deep volcanic winter with probably all organism dependent on photosynthesis dying out for lack of sunlight for decades.

Thumper
2004-Feb-26, 06:03 PM
(roughly on par with the moon opening its eyes and grinning at us before it proceeds to amble off arm-in-arm with the sun)....

Careful daver. In Rick Sobie's world, that is an imminent event.

Shhhh! We don't need another 6 page thread of nonsense on that topic. :roll:

AK
2004-Feb-26, 11:15 PM
Do you think anyone knows what cause it to break up?

I thought there was a consensus that SL-9 was fragmented by a close approach to Jupiter on its previous encounter before the impact, in July of 1992. It passed within 25,000km of Jupiter, was broken apart by Jupiter's gravity, and returned to do some damage two years later.

tofu
2004-Feb-27, 03:42 PM
Do you think anyone knows what cause it to break up?

I thought there was a consensus
oops! I wasn't clear there. Do you think the average person who gets his science news from the mainstream media knows? I don't think they do, because the media was only interested in reporting the "cool" stuff.

lessermystery
2014-Feb-25, 06:55 PM
Hi there,

I'm a little late here. I'm posting because I had a dream about an incoming planet. I want to report what I saw in the dream in the hopes of finding out how close to "reality" the scenario depicted might be.

I only remember the salient points. The daytime sky darkens somewhat, but it's kind of a strange darkening. Suddenly I see smallish smudges of what look like small, smudgy, rainbow clouds every where. Soon these smudges give way to what looks as if the sky is full of holes - like its disintegrating. Suddenly the sky is black. Just as suddenly there appears a white planet, moving rather quickly. That's it. The dream felt so realistic, it's been on my mind for days, and I couldn't help but wonder if it reflected possible reality in some way.

As an aside, if Ceres hit earth, and if the earth is toast, could there be a possibility that life would form again on a larger earth?

antoniseb
2014-Feb-25, 10:11 PM
... if Ceres hit earth, and if the earth is toast, could there be a possibility that life would form again on a larger earth?
The Earth wouldn't be much larger. I expect that even though Ceres has a lot of water on it, the heat of the collision would do a lot to remove most of the water from the Earth and atmosphere, so it would be a fairly dry place after that. Maybe life could form again. Fortunately Ceres is not going to have its orbit changed enough to do this in the next billion years, so we have time to prepare.

Noclevername
2014-Feb-25, 11:25 PM
If Ceres hit the Moon at that speed instead of the Earth, would life still be possible here? And how would the Earth be different? I'm figuring a large vapor cloud ring mixed with the debris chunks, and condensing volatiles raining down on Earth.

Amber Robot
2014-Feb-26, 12:35 AM
What would it be like as Ceres entered the atmosphere?
Uncomfortable.

The upshot is that, at 40 km/s, entering the atmosphere would be a very short period of time.

John Mendenhall
2014-Feb-26, 02:26 AM
Fropm the results page:

Crater Diameter: 6700.0 km
Crater Depth: 4.2 km

In other words, Earth is toast

PS: diameter of Earth= ~12,750 kilometers.

No, it melts. Lava saunas are not good for any life form.

swampyankee
2014-Feb-26, 02:37 AM
This site gives a slightly answer: http://impact.ese.ic.ac.uk/cgi-bin/crater.cgi?dist=20000&distanceUnits=1&diam=933000&diameterUnits=1&pdens=&pdens_select=3000&vel=40&velocityUnits=1&theta=45&tdens=1000&wdepth=2000&wdepthUnits=1

Note that the observer is on the opposite side of the world an is engulfed by the fireball.

publiusr
2014-Feb-28, 09:50 PM
What is this fascination with smaking the Earth with rocks? :D

I'd rather pay off the national debt with a couple rich with ore

iDot10T
2015-Feb-01, 10:47 PM
I have a slightly different question. What would the results be if Ceres hit the Earth in the middle of Yellowstone National Park, considering the super volcano being underneath it?

antoniseb
2015-Feb-02, 01:10 PM
I have a slightly different question. What would the results be if Ceres hit the Earth in the middle of Yellowstone National Park, considering the super volcano being underneath it?
The energy of the collision would be so much more than the difference in heat energy near the surface that you'd have a tough time identifying a difference. Ceres is much bigger than Yellowstone park.

Swift
2015-Feb-02, 01:22 PM
I have a slightly different question. What would the results be if Ceres hit the Earth in the middle of Yellowstone National Park, considering the super volcano being underneath it?
As antoniseb said, it wouldn't make any significant difference. In either case, as the Ghostbusters say, "it would be bad".

DonM435
2015-Feb-02, 01:40 PM
If the first hit weren't fatal, the Earth would injure itself hitting back.

Noclevername
2015-Feb-02, 04:06 PM
I have a slightly different question. What would the results be if Ceres hit the Earth in the middle of Yellowstone National Park, considering the super volcano being underneath it?

The effect of the supervolcano would be less than the margin of error for calculating the Ceres impact.

Squink
2015-Feb-03, 01:38 PM
it would release 193471 billion tons of TNT!! wow...
That's equal to 1.76e17kg TNT.
Earth surface area is 510100000 km^2 = 5.1e14 square meter
So energy release is roughly 345kg TNT per square meter.
Probably get significant crustal melting.