Neighborhood Watch

Last night I had cobbled together a lot of interesting stuff about today’s cosmic near-miss with asteroid 2012 DA14 (a pretty innocuous – even boring – name for something that had the potential to do so much damage). I know the professional astronomers have to catalog this stuff in ways that make sense to them, but something passing inside the orbits of our own weather satellites that’s big enough to flatten a large city should have a more impressive calling card. Like Zul the Destroyer. Or Hoss.

So yes, there was already a good deal of material ready to go but things just got a lot more interesting overnight: Hundreds Injured in Russian Meteorite Event.

Now that we have your attention, try this on for size:

Note that DA14’s orbit isn’t in the same plane as ours, so I’m not certain that a few hours’ difference in either direction would mean we’d be looking at an impact. But keeping that in mind, let’s zoom out beyond our own backyard and into the general neighborhood:

This was yesterday. And that’s just the stuff we know about. As we become more technically capable and intellectually aware, we really should be taking this more seriously.

A fundamental principle of risk management is the concept of risk itself: that is, the level of risk inherent in a given event is a product of its probability multiplied by its severity. This is commonly simplified into a “Risk Matrix”:

Once you’re out the nice comfy green zone, you’d better start paying attention and making plans. Land in the red corner, and you’d better be doing something about it right freaking now because this is some serious $#!+, Bubba.

UPDATE: Neglected to mention the Torino and Palermo impact scales. Torino is a color-coded risk scale meant for public consumption. The Palermo scale is a bit more math-intense.

It’s been estimated that the probability of a football-field sized asteroid like 2012 DA14 impacting Earth within this century is 30%. Being generous, that puts our likelihood in the “probable” category (if I applied the same mathematical limits we use at my day job, it’d be “frequent”).

But that’s just talking about our planet taking a hit. Where and how it hits is of course just as important. Remember: Earth is not just moving through space, it’s rotating, and most of our surface is water. So chances are very good that any Giant Space Rock of Doom would hit water. Of course, that gives rise to secondary risks like tsunamis but what’s a person to do?

Now what if all the cosmic billiards line up and our Giant Space Rock hits a major city? Even worse, an air burst like the Tunguska event? The immediate effects would be indistinguishable from a nuclear weapon:

As it happens, we have a very good idea of how things would unfold in a situation like that since an extremely similar scenario played out before, on June 30, 1908, near the Tunguska River in Central Russia. At 7:14 that morning, a massive blast from what is calculated to have been a 100-meter asteroid occurred somewhere from 3 to 6 mi. (5 to 10 km) above the surface. The region was heavily forested and lightly populated—which was a very good thing—but the devastation was nonetheless stunning. Roughly 80 million trees were leveled or incinerated in a footprint of destruction extending 830 sq. mi. (2,150 sq. km). The energy released by the blast is estimated to have been 30 megatons—or 1,000 Hiroshimas.

An 830 sq. mi blast ring has a radius of 14.4 mi. (23.2 km). Position that over New York City and you’d have destruction reaching deep into Queens in the east and Staten Island in the South; west to Paterson and Montclair, NJ; and north to Yonkers and New Rochelle, NY. Manhattan, the Bronx and Brooklyn would be swallowed whole.

(H/T: Instapundit)

So yes, I think it’s in the national interest for NASA or NOAA to get serious about Near-Earth-Object mapping missions. Private foundations like B612 do great work, but don’t yet have the necessary resources. To my mind this is a public-protection question, which is a proper role for the guv’mint.

I’ll be expounding on these subjects in a decidedly more, um, dramatic fashion in the next several months:

* * *

Melbourne, Florida

“What’s that?” Tommy Hunter had pulled his mother by the hand into the back yard, which was becoming a habit of late. At night, the sky above their home seemed to explode with stars. He was starting to recognize patterns and was immediately drawn to anything new or out of place. What his mother didn’t realize was that once he’d become aware of where his daddy worked, he’d been intently searching for him up there.

“It’s a comet, dear,” Marcy Hunter said patiently. They had encouraged his inquisitiveness, but this latest obsession kept conflicting with bedtime.

“What’s a comet?”

Marcy thought for a minute, searching for an explanation that would fit a toddler’s understanding. “It’s like a big snowball,” she finally answered. “A really big snowball.”

“Big as me?”

“Much bigger,” she smiled.

“Big as daddy’s planes?”

“Even bigger.”

“Big as our house?”

“No, hon,” she said gently. “Big as the whole town.”

He stared at the blue-white smudge that seemed to scrape the ocean, looked back past their neighborhood, and paused to consider his mother’s words. She couldn’t tell if he was impressed or not. “That’s really big,” he finally said. “Is it going to land here?”

“No, baby,” she said. “But it is going to fly right by us in a few weeks.” All the news outlets had been breathlessly talking about it, in fact. It promised to be a real show, if not a bit too close for comfort as it passed between Earth and Moon.

“Okay.” Tommy took one last look and turned back to their house for bed. He was satisfied with his mother’s explanation, as the big flying snowball had been getting bigger lately.

 * * *