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Toutatis
2005-Mar-10, 12:50 AM
http://neo.jpl.nasa.gov/risk/2005em30.html

~81 Gigatons (TNT EQV.) Oooooh!!! That's gotta hurt!!!

But seriously, at an estimated MOID just 'shy' of 0.05 AU and a sigma (LOV) ~|3| one wonders why any -- but in point of fact BOTH -- monitors would post this "solution" --- It can only garner more of the wrong sort of media attention!!! :roll:


With Regards
Dan (The Prodigal 'Carper') Sarandon

PS - If you are reading this much later than the 9'th it won't likely make lotz of sense...

N C More
2005-Mar-10, 12:58 AM
Well, these appear to be pretty good "odds" to me :


Impact Probability: 5.1e-09

0.000000510% chance of Earth impact

or

1 in 196,078,000 chance

or

99.99999949% chance the asteroid will miss the Earth


I'd "bet the farm" on those odds.

Squink
2005-Mar-10, 01:08 AM
Impact Probability: 5.1e-09

[faulty logic mode]

There are over 6.0e+9 people on earth.
So on average it'll kill someone.
It'll kill us all if it hits.
-We're dead!

[/faulty logic mode]

Toutatis
2005-Mar-10, 01:41 AM
I'd "bet the farm" on those odds.


Well hey then! Your broker will be delighted to learn that NeoDys places the 'odds' of a 9/23/2005 event at 8.22E-09 (i.e. ~1:122,000,000) :D

One wonders how 'they' (both monitors) 'figure' an object possessed (Re: orbital parameters) of an MOID ~ .04879 AUs, and an inclination of ~ 53 (Deg) (and hence no significant perturbers in sight) may - even at those odds - evolve a MOID of zero in so little as six MOs time?!?! --- How does that old ditty go? "back at base bugs in the software flashed the message something's out there..." Yeah I think that's it?

Well I'm off to beat the run on marshmallows and franks! :D

Toutatis
2005-Mar-10, 02:01 AM
It'll kill us all if it hits.

Actually an impact yield of 81,000 MT would very unlikely extinguish our species - Though I feel confident in my postulation that it'd 'visit' all of us with widely varying, but in no instance, trivial, degrees of hardship...

OBTW - I enjoyed your 'faulty logic' perspective adjuster :) --- Indeed, as you tacitly stated, statistics will mislead the unwary =D>

Best regards
Dan Sarandon

bmpbmp
2005-Mar-10, 04:32 AM
so this thing is gonna hit us

Toutatis
2005-Mar-10, 05:20 AM
BmpBmp asked:


so this thing is gonna hit us

I think not! :) --- What with 'worst case odds' ~ 1:122,000,000 (IOW 1 in 122 million) I stand a markedly greater chance of being Sus... um..., no! I won't go there! ;)

BTW please don't be alarmed should the odds 'narrow' slightly prior to elimination of this VI (Such is common with initial reduction of the uncertainty region...) Also please bear in mind that the MOID, Sigma(LOV), Inclination and (in the case of '05 and '12) proximate VIs are highly favorable for rapid elimination of this ALL risk - Indeed, one more set may well lay the matter to rest! :)

Sincere apologies should ambiguities in my posts have incited distress!

Best regards
Dan Sarandon

Toutatis
2005-Mar-10, 07:50 AM
As I review my post (immediately above) I see I may have erred a bit on the side of jocularity? I have no desire to behave in an insensitive manner, especially as it seems you are genuinely concerned.

Incase you are unaware of it, please consider the Palermo scale's role as a powerful perspective-lending tool:

It's as simple as this:

The Palermo number represents the common (i.e. base 10) logarithm of the ratio of a given VIs probability of realization to accepted 'background' liability; (i.e. impact liability relative to 'background' = 10^P [where P= the Palermo number Re: the VI in question])

So, with reference to 2005 EM30:

'Worst case' Palermo number (NeoDys) = -2.37 So, 10^-2.37~0.00427 or ~234 --- Hence, based on data available at the time of this writing, 2005 EM30 is ~234 times LESS likely to collide with Earth this September than an unreckoned object over a similar period carrying similar destructive potential...

Please don't be intimidated by the math! Many people find it easier to view negative Palermo figures as 'abstracting' and positive as 'compounding'.

Hence, having noted the sign, merely observe the following relation: V/B=10^|P| (Where V/B = the virtual impact to background impact ratio either compounded or abstracted as per the sign on P)

CIP: 10^2.37~234.4 Because the sign was negative the risk is ~234.4 times abstracted from 'background' --- Was the sign positive the risk would compound background by a factor of 234.4

As a point of reference please note that P=0 indicates an impact liability equal to background -- Ergo VIs having non-positive Palermo figures are, as a practical matter, *NO CAUSE FOR CONCERN WHATEVER* --- But people will be people ;)

I hope this helps put things in perspective when pondering this and future "threats" :D

Very best regards
Dan Sarandon

bmpbmp
2005-Mar-10, 11:38 AM
It puts it a little into perspective but I don't understand the whole thing.

I read the impact page but don't understand all the number out there. For example the size,

Also I just notice the object is no longer on the list would anyone know why that is.

the_shaggy_one
2005-Mar-10, 04:01 PM
probably removed because they got better data, and found there is 0 risk of an impact.

Toutatis
2005-Mar-10, 04:35 PM
Yes :) -- Arc-extension corollary to observations from Tue/Wed (Bassano Bresciano) and Wed/Thu (Spacewatch) – as reported in this morning's DOU MPEC (Daily Orbit Update - Minor Planet Electronic Circular) – allowed refinement of ‘EM30's orbit such that collision is ruled out for at least 1 century :D

Best regards
Sarandon