Asteroid 2012-DA14 will pass within 17,200 miles of Earth at 18,000mph

littlemac1980

I see there are plenty of inventive ideas to deal with troublesome NEO's.

Of course its all hypothetical until something is discovered that needs dealing with.

A strategy for dealing with each such NEO should be formulated based on the peculiar characteristics of each one.

Obviously therefore the most important aspect of any strategy to deal with such is an effective method of discovering them, e.g. more dedicated resources. I'm glad to see the Canadians have been paying attention to my posts here.

Anyway I think given that most of the undiscovered NEO's are significantly less than 1 km in size and, given that I'm suggesting we should have an effective strategy in place to discover them far in advance of a potential impact date, i.e. not last minute haphazard discovery like DA14. I think there should be no problem devising a strategy to deal with them properly. I think if such a threat were identified, there would be far more dedicated scientific minds involved than a hypothetical discussion here might attract.

I would have thought the easiest way to deal with an NEO of <= 1km would be alla Armageddon, but perhaps with a systematic chain of such nuclear explosion points deep with in the Asteroid to break it apart. Obviously carried out at relatively safe distance from Earth - made possible by early detection, and not within a week of a likely impact.

Also would it not be the case that for such a size object the escape velocity required to hurl loose pieces of it into space could by supplied by something as simple as an industrial rubber band.

ps200306

Knowing the characteristics involves more than just observing the asteroid. We still don't even have a good idea as to whether most asteroids are strongly or loosely bound. Evidence for the former is the presence of well-defined impact craters on asteroids. Evidence for the latter is that rotation rates seem to max out at the escape velocities of constituent particles, i.e. they spin as fast they can without falling apart.

Obviously your strategy might vary depending on these characteristics. A nuclear detonation on a rubble heap asteroid might not do much to change its course ... you've still got a rubble heap, and guess what! ... now it's glow-in-the-dark radioactive. :eek:

I still reckon the easiest detection approach for the small ones is to wait until they light up the sky overhead.

littlemac1980

ps200306 wrote: »

Knowing the characteristics involves more than just observing the asteroid. We still don't even have a good idea as to whether most asteroids are strongly or loosely bound. Evidence for the former is the presence of well-defined impact craters on asteroids. Evidence for the latter is that rotation rates seem to max out at the escape velocities of constituent particles, i.e. the spin as fast they can without falling apart.

Obviously your strategy might vary depending on these characteristics. A nuclear detonation on a rubble heap asteroid might not do much to change its course ... you've still got a rubble heap, and guess what! ... now it's glow-in-the-dark radioactive.

You seem to have an uncanny knack of supporting what I'm saying without agreeing with what I'm saying.

So given what you've just said, you'd have to agree that in order to deal with them:

1. They have to be spotted.

2. They have to be spotted in time to allow each to be investigated (i.e. intercepted) before devising a strategy to deal with each one.

3. That they have to be spotted in time to allow such an investigation and follow up implementation of a strategy.

4. That the best way to enable 1, 2 and 3 to be possible is to dedicate more resources than are currently employed to the hunt.

littlemac1980

ps200306 wrote: »

I still reckon the easiest detection approach for the small ones is to wait until they light up the sky overhead.

Just saw your extra edit there, after I'd finished the reply.

Obviously - Although I don't think it needs clarification - I don't agree with that point. Seems like a bit of gamble.

Heads - nice fireworks.

Tails - No More New York

ps200306

Nothing to worry about then ... New York is miles away

Ok, I take your point.

Zubeneschamali

littlemac1980 wrote: »

Heads - nice fireworks.

Tails - No More New York

So you think that's a 50-50 chance?

littlemac1980

Zubeneschamali wrote: »

So you think that's a 50-50 chance?

:mad:

Zubeneschamali

littlemac1980 wrote: »

:mad:

Well if you phrase it differently, it feels a bit different:

Your lotto numbers don't come up: nice fireworks

They do: bye-bye a patch of uninhabited Pacific ocean!

littlemac1980

Zubeneschamali wrote: »

Well if you phrase it differently, it feels a bit different:

Your lotto numbers don't come up: nice fireworks

They do: bye-bye a patch of uninhabited Pacific ocean!

Well - seen as how you brought up probability.

1. Russia - 15th February

2. DA14 - 15th February

Both unrelated significant threats on the same day, highly improbable perhaps - but it occurred. Like I said before while predictions regarding occurrence probabilities tell us something of the likely frequency of a particular type of event recurring over an artificially long period of time, they don't offer any insight into predicting when on that time line such events may occur. Such an event is as likely to occur tomorrow as it is to occur in 500 years time.

A woman who lives 5 miles from me won the €115 Euro Millions - I didn't buy a ticket - I thought the odds of even someone from Ireland winning were far too remote.

Of course accurately defining the probability of an event relies on having the correct data to do so. Estimates by their nature aren't accurate.

I never said "The End of the World is Nigh"

I said - we have to make a much more substantial effort in identifying NEO's - particularly given the events of 15th February.

Only when we do so, will we have a proper idea of how many DA14 objects are out there, and what trajectories they are currently on - then we will also have a better idea of the probability of an impact from such an object, but of course that won't really be important then - because we'll know exactly where they are and we won't just be sitting here naming planets 200 light years away, with or fingers crossed that today isn't the day our numbers come up.

Zubeneschamali

littlemac1980 wrote: »

I said - we have to make a much more substantial effort in identifying NEO's - particularly given the events of 15th February.

I say: no, we don't.

I win!

TheUsual

There's a program on Channel 4 this Sunday night at 8:00 pm about it, asking what it was and where it came from, might be good to watch. It's called "Meteor Strike: Fireball from Space" ... here is the link :

http://www.channel4.com/programmes/meteor-strike-fireball-from-space

What's the likelihood of Earth being struck by another meteorite like the one in Russia? And what can be done to protect our planet?

ps200306

Of course, even if you track down all the NEO asteroids, there's still the comets ... much faster, much less stoppable, and ...

... one coming to a planet near you next year:
http://www.boards.ie/vbulletin/showthread.php?t=2056891093

Only discovered a few weeks ago and already threatening Mars with an event similar in scale to the KT dinosaur killing event on earth 65 million years ago!

Capt'n Midnight

ps200306 wrote: »

Don't know what you're saying here ... a gyroscope or a bicycle wheel doesn't wobble in the absence of a force.

ahhh

the word is precession

ps200306

Capt'n Midnight wrote: »

ahhh

the word is precession

Ok, gotcha. Precession in an asteroid is different to a bicycle wheel or a gyroscope, or the earth for that matter. In the case of the earth the moon and sun pull on the equatorial bulge, causing precession of the rotational axis -- same as if you try to turn the wheel or gyro ... it wants to move perpendicular to the direction you apply the torque.

In an asteroid there is nothing applying a torque, so it spins on a single rotational axis except if it's spinning on an axis other than the one of maximum moment of inertia. Then it can experience "torque-free precession". However, it's expected to change its rotation axis over time so that the precession is eliminated. So only asteroids involved in recent collisions are expected to have such precessions.

TheUsual

Channel 4 now on, documentary about Meteor.

ps200306

TheUsual wrote: »

Channel 4 now on, documentary about Meteor.

Watched it. Something that occurred to me, not directly related to the meteor ... a few years ago I would've looked at that programme and thought "Wow! Amazing footage". But what I actually thought was "Hmm! I saw all the good bits on youtube two weeks ago". They've just sprinkled in a few talking heads, spouting some pretty basic stuff that we probably already knew ... and there's your programme.

It's not a slur on the programme, more a testament to the amazing communication and information we have at our fingertips these days. Whether you're impressed by that will depend on a) if you're old enough to remember when things were different, and b) you watch stuff other than Harlem Shake uploads.