1999 RQ36

[Rokcet Scientist]

Another impactor asteroid on the way to smash Earth: http://www.space.com/scienceastronomy/d ... 00727.html.

[Minimalist]

2182 seems a long way off.

[E.P. Grondine]

It is a long way off, min.

What is not a long way off is the debris stream of Comet Schwassmann Wachmann 3, which intersect the Earth in 2022. That's 12 years from now.

E.P. Grondine
Man and Impact in the Americas

[Minimalist]

If memory serves we pass through the trail of a comet every August... we haven't been wiped out yet. As a matter of fact if you live in a dark area you get one hell of a light show out of it.

[E.P. Grondine]

The Perseids just occurred. But SW3's debris chain is a whole lot different than that.

[Rokcet Scientist]

The Perseids just occurred. But SW3's debris chain is a whole lot different than that.

Are you clairvoyant, E.P.? Or just a doomsayer?
We'll see about SW3's effects, won't we? No use worrying about it because there's nothing we can do about it anyway.

[Minimalist]

Doesn't sound all that dire.

http://en.wikipedia.org/wiki/73P/Schwassmann-Wachmann

In 1995, 73P began to disintegrate.[2] It was seen to break into five large pieces labelled 73P-A, B, C, D & E. As of March 2006, at least eight fragments were known: B, C, G, H, J, L, M & N. On April 18, 2006, the Hubble Space Telescope recorded dozens of pieces of fragments B and G. It appears that the comet may eventually disintegrate completely and cease to be observable (as did 3D/Biela in the 19th century), in which case its designation would change from 73P to 73D. It is now known to have split into at least 66 separate objects.[3] Nuclei C is the largest and the presumed principal remnant of the original nucleus.[4]

The fragments were passing the Earth in late April and early May 2006, coming nearest to the Earth around May 12 at a distance of about 11.9 million km (7.4 million miles). That is a close pass in astronomical terms (0.08 AU) though nothing to be concerned about. In 1930 when it passed the Earth this close, there were meteor showers with as many as 100 meteors per minute. However, recent analysis by P. A. Wiegert et al.[5] suggests that a recurrence of this spectacle is unlikely.

In 2022, the comet fragments are expected to pass nearer to the Earth than in 2006. If the fragments continue to break up, it may become impossible to track all of them since each time a fragment splits, the resulting sub-fragments are fainter and have divergent trajectories.

[E.P. Grondine]

Wishing and hoping will not ensure that SW3 simply turns into magic comet dust, which is the current NASA PR line.

What you have to remember is the research bias of NASA: its budget for the most part is controlled by manned Mars nuts, who think we have nothing better to spend space money on than flying a few men to Mars for a few days, and its astronomy budgets are controlled by cosmologists who want their telescopes funded.

Both groups view money spent on impactor detection as a threat to funding for their clients, and the funding for actual pro-impact research is zero, while the anti-impact researchers are well funded.

Let's say that SW3 turns to magic comet dust. There is good evidence that cometary dust veiling has led to past climate collapses, but again research funding has been limited, so we are not sure how severe the effects of SW3's dust may or may not be.

If a 30 meter piece of SW3 hits, you get 5 kiloton airburst. If a 60 meter piece of SW3 hits you get a 15 megaton airburst.

I have a headache right now, but I seem to remember that SW3 was about 1,500 - 2,000
meters across before it fragmented, and that telescopes were unable to image fragments of 30-60 meters, but only fragments larger than this.

To make this clearer for you, its not that they do not exist, its simply that they could not be imaged because the telescopes were not powerful enough.

[Minimalist]

Don't you think there is a little bit of a difference between "passing through the trail of a comet" and getting hit by the comet itself?

Comets actually have two tails: the dust tail and the gas or ion tail. The
names should tell you what is in them. Both tails always point away from
the Sun, independent of the comet's motion. The dust tail is formed of
solid particles escaping from the cometary nucleus into their own solar
orbits and may be slightly curved.

http://www.newton.dep.anl.gov/newton/as ... AST148.HTM

[Rokcet Scientist]

research funding has been limited, so we are not sure how severe the effects of SW3's dust may or may not be.

What difference does it make?
Suppose we learn in 2012 (due to richly funded research budgets) that a 200 meter chunk will impact somewhere in the northern hemisphere (but we don't know exactly where yet). What are we going to do about it?

The only, and disastrous effect will be the mother of all panics, wars all over the place, large-scale looting, general lawlessness, opportunistic violence round every corner, and the complete destruction of the social fabric. I.o.w. terrible, but unneccessary massive suffering as a result. A decade of self-inflicted hell on earth...

That rock will be heaven sent (!) to end all that unspeakable misery in beautiful cosmic fireworks.

No thanks, E.P.
Go terrorize the Klingons or something!
But please spare us your panic stories. They're dangerous. You're dangerous!

[E.P. Grondine]

What difference does it make?
Suppose we learn in 2012 (due to richly funded research budgets) that a 200 meter chunk will impact somewhere in the northern hemisphere (but we don't know exactly where yet). What are we going to do about it?

The only, and disastrous effect will be the mother of all panics, wars all over the place, large-scale looting, general lawlessness, opportunistic violence round every corner, and the complete destruction of the social fabric. I.o.w. terrible, but unneccessary massive suffering as a result. A decade of self-inflicted hell on earth...

That rock will be heaven sent (!) to end all that unspeakable misery in beautiful cosmic fireworks.

No thanks, E.P.
Go terrorize the Klingons or something!
But please spare us your panic stories. They're dangerous. You're dangerous!

Wrong, RS. We can hit a chunk that size with multiple non-nuclear charges and fragment it into smaller less deadly pieces. For climate problems we can alter planting times, food storage, etc

Unlike the Klingons, SW3 is there. If it doesn't turn to dust, as NASA hopes, the panic you describe happens if actions are not taken.

You seem to be confused, or trying to spread confusion. As far as me being dangerous, its the impactors that are dangerous. Personally, I think you're being ungrateful.

As far as richly funded research budgets goes, where did you get that idea?

[Minimalist]

multiple non-nuclear charges and fragment it into smaller less deadly pieces.

That idea is under fire, E.P. I have heard it suggested that you are advocating converting a bullet into a shrapnel spray.

[Rokcet Scientist]

What difference does it make?
Suppose we learn in 2012 (due to richly funded research budgets) that a 200 meter chunk will impact somewhere in the northern hemisphere (but we don't know exactly where yet). What are we going to do about it?

The only, and disastrous effect will be the mother of all panics, wars all over the place, large-scale looting, general lawlessness, opportunistic violence round every corner, and the complete destruction of the social fabric. I.o.w. terrible, but unneccessary massive suffering as a result. A decade of self-inflicted hell on earth...

That rock will be heaven sent (!) to end all that unspeakable misery in beautiful cosmic fireworks.

No thanks, E.P.
Go terrorize the Klingons or something!
But please spare us your panic stories. They're dangerous. You're dangerous!

Wrong, RS. We can hit a chunk that size with multiple non-nuclear charges and fragment it into smaller less deadly pieces. For climate problems we can alter planting times, food storage, etc

Unlike the Klingons, SW3 is there. If it doesn't turn to dust, as NASA hopes, the panic you describe happens if actions are not taken.

You seem to be confused, or trying to spread confusion. As far as me being dangerous, its the impactors that are dangerous. Personally, I think you're being ungrateful.

As far as richly funded research budgets goes, where did you get that idea?

IF a really big rock is going to hit earth, say before the middle of this century, there is nothing effective we can do about it. We don't have the technology.
Shooting it with rockets with bombs, nuclear or otherwise, is probably the stupidest thing we could do, because if that rock breaks into several pieces, that 'breaking up' will be with the force of humongous explosions, forcing all those pieces into just as many different, totally unpredictable trajectories, all with different points of impact. Can you imagine twenty 100 megaton bombs randomly hitting Earth's surface?

If I have the choice between 1) a decade of global panic and mayhem, and finally a huge armageddon that end's it all, and 2) continuing the next decade in blissful innocence, thus relative 'peace', with a sudden big bang at the end that vaporizes all of us, I'll choose the latter every time.
The end result may be the same for both scenarios, and unavoidable, but the decade leading up to it will be vastly different.

[Digit]

I have yet to see any solid science suggesting that one large impact is less dangerous than many small ones Min.
Logic suggests that ablation would be more effective again numerous small objects, also some materials would logically miss the Earth after disruption.
And again, if an impact tsunami is proportional to mass and velocity, smaller impacts must be less dangerous.

Roy.

[Rokcet Scientist]

And again, if an impact tsunami is proportional to mass and velocity, smaller impacts must be less dangerous.

A grain of sand at 100,000 mph will blow your house to smithereens. And the neighbours'.