K-T event did NOT wipe out dinos

[Rokcet Scientist]

[...] he has studied the issue a great deal, far more than the rest of us I dare say, at least from the point of view of native-American sources.

The 'church fathers' studied their 'issue' a great deal too, "far more than the rest of us I dare say".
Nevertheless they couldn't be more wrong.

The amount of time or effort spent studying a subject isn't proportional to its veracity. It simply doesn't make it one iota more, or less, true. It's got nothing to do with it.

The amount of time and effort spent studying a subject may, however, indicate an obsessive compulsion and a fundamental feeling of insecurity (as it did with the 'church fathers' and does with all of today's 'religious scholars', ministers, priests, imams, etc. etc.).
And over sensitivity for 'persecution' – a.k.a. paranoïa – doesn't make it any easier: it adversely affects personality traits and social acceptability.

[Digit]

There are two points here as I see it, one is the cost of Martian exploration and 'tother the subject of a Terran impact scenario.
Now both proponents have agree that the cost of Martian exploration would fall in the future.
Can't see that.
If either or both mean as a percentage of an increasing GDP then I'll buy.
If we take the cost and compare the landing a one pound weight on Mars against the cost of producing one pound of Steel I see no reason to assume that the ratio will change unless an entirely new source of fuel for the trip is developed.
So is Martian exploration worthwhile?
In monetary terms, no! But then neither was much of Earth's exploration.
Terran impact. There is often a tendency amongst people to confuse risk with result.
For example, if I was to guarantee that some time in the next week you were going to stub your toe, few will change their life style to avoid what will definitely happen.
On 'tother hand if I guarantee a fatal accident in that time scale most would try to avoid it, but what if I were to guarantee the same result with a one in a million certainty?
So what are the odds of such an impact, that's easy, 100 per cent! The only subject open to discussion is the time scale.
Currently the world's governments are committing trillions to combat 'man made' global warming, this despite the 'science' being questionable, (more scientists signed the Manhattan Declaration denying it than signed the IPCC reports).
So here we have vast amounts being spent on something that may be beyond our control and probably far less dangerous than an impact and little being spent on that which is guaranteed to occur and that we may be able to protect against.
So! Where would you spend your tax dollars?

Roy.

[Minimalist]

Sadly, Dig, tax dollars seem to be spent on those projects which will provide jobs to various congressional districts.

Further, no one can doubt the wave of technical advancement that resulted from the lunar program which also provides a visible benefit to people. By all means researchers involved in the hunt for near earth objects should continue but they need to demonstrate that they can detect problems far enough in advance for us to do anything about it. I have no doubt that eventually they will perfect their techniques.

I do hope we don't get blown up in the meantime.

[Digit]

Granted about the spin offs Min but I can't see see Mars visits being more than a one off till a new heavy lift vehicle is devised, and as regards spin offs, such a vehicle would obviously be an asset in dealing with any incoming objects.

Roy.

[Minimalist]

As an engineer yourself, do you agree that establishing a long-range goal requiring innovation is a worthwhile endeavor?

For much of the time since the industrial revolution it seems that these goals were primarily military....and look where that got us!

[Digit]

Yes I do Min. When you consider that such development would have spin offs that could be useful, plus the outcome if we don't, such a failure could amount to mass suicide.
We Know that a large impact is inevitable, in the past all we could do was dig a hole, climb in and pull it in behind us, now, for the first time we are approaching a position where we may be able to protect ourselves, failure to do so would, IMO, be the single most stupid act that mankind has accomplished to date.
We don't have to talk about a mass extinction event Min, imagine Tunguska over New York, the 'Big One' in California isn't even in the same league!

Roy.

[Minimalist]

There was a special on last night about some guy who maintains there was a tsunami in Australia some 500 years ago caused by an impact. The science is being debated but again the folklore is on his side. Trouble is that they think it hit near New Zealand and there is no evidence of a tsunami on New Zealand at that time. Still, the point remains, it doesn't have to hit land. A strike in the north-Atlantic would do plenty of damage.

Considering some of the money pissed away on various research projects something that could enhance detection certainly seems to be a worthwhile investment. Stopping such a target seems like sci-fi at the moment but lots of things that were sci-fi in the 50's are reality now.

[Digit]

Your countrymen have twice demonstrated that you have the ability to hit a small, fast moving target Min, and I don't doubt that we could come up with some vary serious fire power, if not with the first barrel then certainly with the rest of the magazine, given sufficient warning!

Roy.

[Minimalist]

Breaking it up just creates a lot of fragments which would still hit. I've seen concepts for deflecting the entire asteroid so that it misses.

[Digit]

Granted Min, and to be honest that argument has as much validity as the suicidal Lemmings!
Imagine an impacter several miles across, the leading face will impact the Earth's surface whilst the back end is still above Earth's atmosphere, in other words Earth's atmosphere would offer no protection what so ever!
Now let me see you make the same argument for lots of little pieces, I think you'll find that the argument doesn't hold up, even assuming that the impacter's entire mass struck and that none was deflected away from us.

Roy.

[Minimalist]

Now let me see you make the same argument for lots of little pieces

Define "little" in that instance. If you break it up into 50 1/4 mile pieces we'd still be in deep shit. It would be like getting carpet-bombed from space.

Something that size needs to be spotted a lot further out and dealt with there.


http://www.space.com/businesstechnology ... 00211.html

The idea of blowing up an asteroid makes for good movie scripts, but is not the way to do it in the real universe. Many of the fragments would remain on a collision course and like the blast from a shotgun; the fragments can do up to ten times as much damage as the original, intact object.

[Digit]

can do up to ten times as much damage as the original, intact object.

That simply defies logic Min and I note that the author offers no maths etc in support of that statement.
As you asked, define small. If comets adhere to Whipple's 'dirty snow ball' theory, and if Tunguska was such a comet then much of the fragments would logically burn up on reentry, lose mass from heating and/or be slowed, all of which would reduce the impact and blast damage.
Can you offer a serious reason as to why fragments would be more damaging than the mother load 'cos I certainly can't?

Roy.

[Minimalist]

Multiple hits, My earlier carpet bombing analogy.

I agree it matters on the make up of the object

A solid object of the size you mentioned getting that close is going to be the end of the line regardless.

[Digit]

The analogy is correct I think Min. Halving the mass halves the kinetic energy so what I think they mean, badly explained, is that the single large mass would take out New York with a massive crater and splitting the mass could take take out new York and Chicago with smaller craters.
Where you live might just effect your views on the best approach I think!

Roy.

[Minimalist]

To bring this back full circle to E.P.'s original concept (and, E.P. by all means, correct me if I'm wrong) is that the single block taking out NY would create enough of a disaster through tsunami, atmospheric calamity, nuclear-winter and earthquakes to make those people living in Chicago wish they had died faster.

The extent of that scenario seems to be the basis of the dispute.