Meteorite damage in Russia!

[Jason Thompson]

In the early hours of this morning a meteor entered the atmosphere above Russia and broke up.

http://www.bbc.co.uk/news/world-europe-21468116

News is still coming in, but so far it seems over 700 people have been injured, over 100 of them requiring hospitalisation. Damage has been recorded in several towns in the area, and the shockwave blew out windows and caused a factory to collapse. Injuries are mostly from broken glass, it seems.

If anyone doubts the value of research programs to find rocks like this one in space, consider that all this damage was done by the shockwave when it hit the atmosphere and broke up, not by impact, and that the rock in question was probably only about a metre across. Tonight another space rock, designated 2012 DA14, is passing close to Earth. So close, in fact, that it is within the orbit of geostationary communication satellites. It won't hit us, and this morning's event appears to have been caused by an unrelated rock (judging by the location and the reports of damage and visual evidence it seems to have come in from a totally different direction), but DA14 is about fifty times wider and hence about 125 thousand times as massive, and even that is tiny for an asteroid. The consequences if one of these things hits us could be horrific, and yet funding for programs to find and work on ways to protect us from these things is really hard to secure.

[Dirk Gently]

Quite scary news when you stop & think about it.
I'm glad our planet isn't any bigger & we have the moon & Jupiter as protection or we could have been wiped out centuries ago.

[MinaHarker]

Quite scary news when you stop & think about it.
I'm glad our planet isn't any bigger & we have the moon & Jupiter as protection or we could have been wiped out centuries ago.

There have been some interesting models which show Jupiter might fling just as much stuff towards us as it deflects away, I studied it a bit at uni.

The Moon offers pretty much zero protection: http://calgary.rasc.ca/images/Earth_Moon.gif

The fact is that, currently, there is almost nothing we can do about The Big One.

[Zbigniev Hamson]

65 million years since the last one. I'm not overly worried

[Nyder]

It certainly seems to have been hectic in the skies today!

[MinaHarker]

Hmm, but it need not be as big as the one that did the dinos to be a disaster. If the Russian one had come in a few hours earlier it would have hit northern England...

[Zbigniev Hamson]

Hit, or just wreaked the same level of "disaster" as it did in Russia? Either way I'm glad to have found something I'm even less worried about than deadly horse drugs in my lasagne

[MinaHarker]

Hit, or just wreaked the same level of "disaster" as it did in Russia? Either way I'm glad to have found something I'm even less worried about than deadly horse drugs in my lasagne

Not sure what you mean by your first sentence?

Northern England is far more densely populated than the Urals. The combination of shock wave and impact would have been far worse here in terms of damage and injury/loss of life.

[Jason Thompson]

Considerably worse than Russia. Was 1000 injuries and a billion rubles worth of damage in six cities and four towns not disastrous enough for you? Britain is quite a bit more densely populated. The same blast over our sky would have caused far more damage and far more injury and potential loss of life.

And that was a very small one. If you want to not worry about it because you personally can't do anything about it then fine, but it's not a situation that can be ignored by everyone.

[Jason Thompson]

I'd also like to mention that the last really big impact was actually in 1908. Only the fact that it occurred over a forest prevented it being one of the biggest natural disasters (in terms of human casualties) in recorded history. The event would have easily obliterated London, for example.

[Zbigniev Hamson]

That's exactly my point. Even these "really big impacts" are 100 years apart and they have very localised effects. With 2/3 of the Earth's surface water and vast swathes of the other 1/3 sparsely populated, they're just not significantly worth worrying about. You say "only the fact that it occurred over a forest" as if that's a really lucky break whereas, even with mankind's ubiquitous spread over the planet, it's still actually most likely NOT to be over anywhere urban. Something much bigger that could come along and do really significant global damage, more than likely, won't come along until after the human race has either died out or ascended to the next plane of reality. Compared to the much larger risks and death tolls associated with earthquakes, volcanoes, viral epidemics, wars, famine, muggings, horse lasagne etc, I just don't see it as anything to fret over too much. It's got noting to do with it being something I can't personally do anything about. Fine if you don't agree with me, but that's my stance in the matter.

Cool videos though.

Edit: changed the word "muggins" to "muggings", because I think the former severely over-estimated the threat that I pose.

[MinaHarker]

I didn't say it was worth you worrying about. I just find it all extremely interesting.

[Zbigniev Hamson]

True. I know my comment followed yours but it wasn't specifically a reply to that one.

[Jason Thompson]

Even these "really big impacts" are 100 years apart and they have very localised effects.

100 years isn't long, and 'localised effects' won't be much comfort to anyone in a place that's actually hit, will it?

Something much bigger that could come along and do really significant global damage, more than likely, won't come along until after the human race has either died out or ascended to the next plane of reality.

I'd love to see your statistical analysis that leads you to that conclusion!

The number of rocks we are discovering in space is increasing exponentially every year. Comcommitant with that is the number we are finding that cross Earth's orbit. In the past decade quite a few have been observed passing us by quite closely, and some of these have qualified as 'global effect' impactors.

The fact is we don't know when the next one will hit, or even if we will see it coming. I don't think that makes it something that can just be ignored. I'm not arguing for this to be a major priority over any other risks, but the simple fact is that this one is woefully underfunded even given its 'lower risk' value compared to these other things. And of course we know how 'risk-blind' the human race in general is. The risk from volcanoes, for example, could be significantly reduced if huge numbers of people didn't decide to live on the side of active ones!

Cool videos though.

Very much so.

[MinaHarker]

This map is good: http://szyzyg.arm.ac.uk/~spm/neo_map.html

[Zbigniev Hamson]

The number of rocks we are discovering in space is increasing exponentially every year. Comcommitant with that is the number we are finding that cross Earth's orbit. In the past decade quite a few have been observed passing us by quite closely, and some of these have qualified as 'global effect' impactors.

Discovering something doesn't make it more of a risk though...

Surely the fact that complex life even managed to evolve, and that the fossil records go back 65 million years until the last major global catastrophe, is all the statistical analysis that's required? This hasn't been an issue throughout recorded human history and, as far as we can tell, for 10,000 times longer still than that (a few cuts and bruises and smashed windows aside). Asteroids haven't suddenly got more numerous and/or aggressive in the last couple of decades just because we've been noticing them more.

I agree that it's all very interesting, but I also think at the opposite end of the scale from "risk blindness" there's a lot of "risk exaggeration" and I'd put this in that camp.

[Jason Thompson]

Discovering something doesn't make it more of a risk though...

No, of course it doesn't. But knowing about it makes us aware of that risk. Conversely, just because we were ignorant of the existence of asteroids until the 1800s doesn't mean we weren't at risk before then.

Surely the fact that complex life even managed to evolve, and that the fossil records go back 65 million years until the last major global catastrophe, is all the statistical analysis that's required?

That's a massive oversimplification. There have been several mass extinctions since life evolved on this planet, and even if that were not the case, the fact that something happened 65 million years ago does not in any way serve to inidicate the risk of it happening in future. You can't do statistical analysis on one data point!

This hasn't been an issue throughout recorded human history and, as far as we can tell, for 10,000 times longer still than that (a few cuts and bruises and smashed windows aside). Asteroids haven't suddenly got more numerous and/or aggressive in the last couple of decades just because we've been noticing them more.

This falls squarely into the 'it hasn't happened before so we'll be OK' kind of reasoning that led to all three major NASA mission disasters. Just because it hasn't happened before doesn't mean it won't happen tomorrow, and just because we didn't know about asteroids before 1831 doesn't mean it couldn't have happened at any time, does it?

I agree that it's all very interesting, but I also think at the opposite end of the scale from "risk blindness" there's a lot of "risk exaggeration" and I'd put this in that camp.

I disagree, for the reasons stated. We know it hasn't happened yet. We don't know if and when it will happen again. We do know there is a lot of stuff out there, and we do know that a lot of stuff comes damn close, and we do know that a not insignificant portion of that stuff has the capability to cause a global disaster if it does hit. It is not exaggerating the risk to suggest that, as we are now in a position technically to possibly do something about it, it would be worthwhile making sure we can deal with it rather than just sit around and wait as if its in the lap of the gods.

No-one is saying this will happen in our lifetimes, but we can be reasonably certain that it will happen.

[Zbigniev Hamson]

You can't do statistical analysis on one data point!

That's not the case though is it. If we'd been whizzing past the Earth on a spaceship one day and just happened to see an asteroid hitting it, and then flew off into space and never looked at Earth again, we'd have no idea if it happened every day or was a massively rare event. THAT would be having one data point.

If you count the number of days in 65 million years and you're interested in "did a massive, extinction event-sized asteroid hit the Earth on this day (y/n)?" then you have getting on for 24 billion data points. That's a massive statistical sample and gives you a very good idea of the likelihood.

Likewise, while not knowing about asteroids before 1800 doesn't mean there was no risk before that date, the fact that no-one knew about asteroids before 1800 is in itself an indicator of the risk. We certainly knew about being struck by lightning before 1800 simply because of the fact that it happened.

Something not happening throughout recorded human history is every bit as useful a statistical indicator as something happening every other day.

[MinaHarker]

That's not the case though is it. If we'd been whizzing past the Earth on a spaceship one day and just happened to see an asteroid hitting it, and then flew off into space and never looked at Earth again, we'd have no idea if it happened every day or was a massively rare event. THAT would be having one data point.

If you count the number of days in 65 million years and you're interested in "did a massive, extinction event-sized asteroid hit the Earth on this day (y/n)?" then you have getting on for 24 billion data points. That's a massive statistical sample and gives you a very good idea of the likelihood.

Likewise, while not knowing about asteroids before 1800 doesn't mean there was no risk before that date, the fact that no-one knew about asteroids before 1800 is in itself an indicator of the risk. We certainly knew about being struck by lightning before 1800 simply because of the fact that it happened.

Something not happening throughout recorded human history is every bit as useful a statistical indicator as something happening every other day.

I think you are missing the difference between a very rare worldwide disaster sized event, and a smaller local disaster event. It sounds, from your posts, as though you think the strike 65 million years ago was the only other one that has ever occurred.

[Zbigniev Hamson]

No, I was just talking about one and not the other (in that particular post). Further up I've talked about both. Above I was just saying that, just because only one event of that scale has occurred in 65 million years, that doesn't mean we have only one data point. All those days where it DIDN'T happen are equally valid data points.

[Jason Thompson]

But those days where it didn't happen don't allow you to extrapolate forwards. We don't know, based on one impact 65 million years ago, whether they happen every billion years, hundred thousand years or 60 million years give or take five million.Yes, you have millions of data points, but if you're trying to work out the chances of an impact and those millions of data points only include one, you don't have a pattern to work from.

As I said before, and as NASA found out three times, 'it hasn't happened yet' is not an indicator that it won't happen soon or at all.

I don't think we can afford to be complacent about it any more than we can about aircraft safety, for example. Statistically air travel is the safest. Accidents are rare, but when they do happen they tend to be disastrous. I don't think anyone would argue that the rarity of such acidents means we shouldn't expend much effort working out solutions so they don't happen again in future. So it is with large impacts. They may be infrequent, but the scale of consequences is too great to be ignored.

[MinaHarker]

This is interesting: http://www.passc.net/EarthImpactDatabase/Worldmap.html

[Zbigniev Hamson]

But those days where it didn't happen don't allow you to extrapolate forwards. We don't know, based on one impact 65 million years ago, whether they happen every billion years, hundred thousand years or 60 million years give or take five million.Yes, you have millions of data points, but if you're trying to work out the chances of an impact and those millions of data points only include one, you don't have a pattern to work from.

Negative results are as significant as positive ones. If you're trying to work out how likely it is that we're going to get wiped out by an asteroid impact then all the millions of consecutive years where that didn't happen are as statistically important as the one year where it did. If someone flipped 64,999,999 tails and one head with a particular coin, that would give you plenty of information on how likely you were to get a head in the next 100 or so flips. There's no guarantees with random chance of course, but that doesn't mean we have no idea or can't extrapolate at all...

[MinaHarker]

Except, as we keep saying, there hasn't just been a single impact event 65million years ago.

There have been many. I have shown a link to a map of NEOs and a link to a map of known impact craters (which, due to erosion etc, does not show all impact sites).

Furthermore, it isn't just the Big One that wipes out the human race that is concerning. Any asteroid a few metres across or more, of which there are a large number that are known to cross Earth's orbit (http://en.wikipedia.org/wiki/List_of..._minor_planets), can cause a disasterous impact event the scale of which depends upon where it hits. That's just the known ones.

Just because they wouldn't wipe out the whole human race, that doesn't mean we should not try to map these things and have plans in place to deal with them if we need to - the same way we research and map earthquakes, tsunamis etc.

I don't mean the worry should be all-consuming and at the expense of everything else, just that it is worth spending a bit more money and research on that at present. Currently NASA gets 0.5% of the federal budget, and only 0.05% of that is spent on this research. I don't have the figures for the UK - but I know Spaceguard UK gets no government funding at all, so the amount might well be zero.

[Dirk Gently]

Very interesting discussion folks.

I may be wrong but I believe that there is an object currently being tracked that is on a near earth orbit, and is believed to "hit" us in about 20 or so years time. Although recent tracking has it now missing us by some miles (although that is still near enough to effect us & for debris to hit).