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2004 MN4 Asteroid Odds Inching Up Again
bfwebster writes "The latest update from NASA now gives 2004 MN4 a 1-in-37 chance (probability of 2.7%) of hitting Earth on April 13, 2029. That's a bump up from the 1-in-46 (2.2%) odds given this weekend and almost a 10x increase in probability from the original 1-in-300 odds announced late last week. Interesting times, indeed."
Yes, April 13, 2029 is a Friday.
John.
Space.com says it will take a few months, unless they use Arecibo's radar--which would really help norrow the orbit.
I ran it through the calculator for a 400 meter asteroid (from the article) made of dense rock (assumed) at 17 km/s and 45 degree impact (suggested by the calculator). I also dropped it in 1000 m of water, as it has a 75% chance of landing in the oceans.
Results
- Impact Energy: 1.23 x 10^19 Joules
- Crater Formed in Seafloor: 2.46 km diameter
- Earthquake: 6.0 on Richter Scale
- Radiant Flux at 100 km: 7.68 times that of sun
Numbers should, of course, be taken with a grain of saltCrazy, I was just checking my bookmark on this when the slashdot article popped up. Anyways..
Here is the wikipedia page explaining the Torino Scale. I still wouldn't worry about it until the thing hit at least a 8 or so. The article gives a nice explanation of what astronomers would do in warning the governments in the event they thought this thing deserved any real attention.
Torino ScaleTry not to let life get in the way of living.
1 in 37! Nice. =)
(Roulette has 18 black, 18 red, and 1 green for those not in the know.)
Education is the silver bullet.
According to this calculator the crater would be about 9 kilometers in diameter, it would cause a 7.1 strong earthquake and a 44 m/s shockwave a hundred kilometers from the epicentre. (Assuming 90 degree collision angle and iron composition - basically, the worst.)
Note that this assumes 4940 megatons in kinetic energy, and Nasa says it's "only" 1600.
First, my apology that I made an error in the previous post. The actual energy requied to move a 300m cube (with density of 3 g/cm3) laterally at 1km/s is about 4e16 joules (I shamefully admit that I forgot about SI unit).
Now let's fix up some bad concepts here. First, a detonation of a hydrogen bomb will provide impulse force, neither constant or gradual. Second, there is no mass in gamma ray (it's a photon). Alpha particles will be produced but it's insignificant compared to the asteriod, so we can omit them out of our consideration.
Now taking your number (thanks by the way), 1 mega ton TNT is about 4e15 joules. And like I said, a half of radiation just simply escapes away from the asteroid. Now suppose if the efficiency of radiative momenta is 100% (which is very unlikely, but let's assume that), then it would take 20 mega-ton TNTs at a minimum to give it a little push.
But again, the 100% efficiency is unlikely. Some photons will part its energy into heat, or re-radiated away. So for the safety factor, I'd feel confident if we are to deploy about 10x, or 200 mega-ton TNTs simultaneously.
It's not an impossible number, perhaps.
(ps. I ignore many physics here; the asteroid is bounded by the Sun's gravity and so its potential field must be taken into account as well..well, I will worry about that when NASA comes knocking my door for help).
Latest NASA update shows limited chance of impact.
1 in 56,000.