RV-size asteroid to get closer to Earth than the moon

Since we're not saying the same thing, no. The scale *implies* consequences for numbers 8-10, but the scale exists merely to indicate the level of probability of impact. Obviously the size doesn't matter (that's what she said) if there's very low risk of impact on Earth.

When an impact probability rises on the scale, that indicates greater likelihood that the object will fall into the Earth's gravity well and head toward the surface.

Numerically, the vast majority of stuff that does hit is too small to make it through the atmosphere. Other things are large enough, but still far too small to cause serious damage beyond its ground zero.

Siberia has had three in about a century, another one hit the Bering Strait, Greenland has had one in the past few years, the S.Am rainforest has had at least two, and most notoriously, an impact in the southern Indian Ocean was attributed to a nefarious conspiracy to test a South African nuke.

Even today, the most likely scenario for an impact that threatens civilization (about one-half mile, and depending of course on where the impact occurs) is still zero warning.

I remember those hours during the night that "Apophis" was being evaluated by astronomers all over the world -- I kept loading page after page, and watched its Torino number drop from 1 to 0. Since that time the sheer amount of resources searching for hazardous space debris has risen drastically, and will continue to.

Ten years earlier the SL-9 impacts on Jupiter finally sobered up the astronomical community, which had still some jokers who denied that anything was impressive was going to happen. One of the astro mags had a story, "The Big Fizzle Is Coming", and the writer of that one may have changed his or her tune, but more likely scribbled some semantic rationalization.

Per NASA, The Torino Scale is a tool for categorizing potential Earth impact events, that captures the likelihood and consequences of a potential impact event. Thus, it is a categorization tool, and the output is that categorization.

It does not exist merely to indicate the level of probability of impact. In fact, the level of probability impact is assigned by whoever in the NEO community calculated those probabilities. Torino is just a Scale, a ruler. It is silent on a any NEO's collision probability, just like the tape measure is silent on how tall I am.

Now, I would agree with you, if you're saying the only "fact" in Torino is the impact consequence on the far right-hand side, i.e. Where the collision likelihood is basically 100%. Any other consequence is theoretical, a sort of equivalency, and those consequences are conditional on impact probabilities that are, by definition, estimated. However, as I said earlier, based on my cursory review actual damage from real impacts, those consequences given impact likelihood = 100% look pretty accurate.

I remember SL-9 very well.

It was beautiful and scary. It was a wake-up call, or should have been so.

And I would also agree that A Big One with our names on it is Out There. But people freak at every piece of space rock that whizzes by us, be it a fraction of our distance to the moon or multiples of that distance. They are as misguided as those who think space is so vast we are waiting for a rocky Godot - or we can blast The Big One like Bruce Willis.

It'll happen some day, maybe next month, maybe in a decade, maybe 100 or 1000 years from now. For now, all I can do is be informed, read up, know the pros and cons, and act accordingly. Your ping list is invaluable. Thank you.

[wiki] In celestial mechanics, the Roche limit, also called Roche radius, is the distance within which a celestial body, held together only by its own force of gravity, will disintegrate due to a second celestial body’s tidal forces exceeding the first body’s gravitational self-attraction. [/wiki] The ISS isn’t a celestial body*, and isn’t held together by its own gravity.

Exactly my point: Referring to Roche's Limit in regards to the asteroid at hand - which is held together primarily by cohesive forces, not by gravity - is misleading. That was all that I wanted to say.

*Let's not waste time arguing about the definition of "celestial body." Roche's Limit is legit when speaking about ANY physical object in orbit around a larger physical object in the Cosmos (as long as said object fulfills the further constraint of being held together only by gravity).

Regards,

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