chongo's Journal: 2004 MN4 asteroid update for 25-Dec-2005 13:12:29 UTC

You may have, or will soon hear about the asteroid 2004 MN4. What is significant about 2004 MN4 is that it has reached an all-time hazard level on the Palermo Scale, and the Torino scale .. two scales that measure the hazard rating of an asteroid.

The most sginificant event is the close encounter between Earth and 2004 MN4 on 2029-04-13 around 21:21 UTC. We currently estimate hit the Earth, it would impact at a speed of 12.6 km/sec. It would hit the Earth, it would impact at a speed of 12.6 km/sec. It would You may have, or will soon hear about the asteroid 2004 MN4. What is significant about 2004 MN4 is that it has reached an all-time hazard level on the Palermo Scale, and the Torino scale .. two scales that measure the hazard rating of an asteroid.

The most significant event is the close encounter between Earth and 2004 MN4 on 2029-04-13 around 21:21 UTC. We currently estimate that there is a 1.6% chance that 2004 MN4 will impact the Earth during that pass. This has given 2004 MN4 a hazard rating of 4 on the Torino Impact Hazard Scale. A 4 means:

A close encounter, with 1% or greater chance of a collision capable of causing regional devastation.

The highest previous was a 1.

2004 MN4 is also rated with a +1.02 on the Palermo Technical Impact Hazard Scale Torino Impact Hazard. No other object has every reached close to +1.0 before.

2004 MN4 appears to be an asteroid that is 420 meters in diameter. It has a mass of about 1.2e+11 kg. Models show that IF it were to hit the Earth, it would impact at a speed of 12.6 km/sec. It would take only 1.4 second to pass from the upper Stratosphere to the surface. The nearly 1/2 km wide asteroid would pass through Earth's atmosphere intact, and strike the surface with an equivalent explosive force of about 2200 Megatons of TNT. Such an impact would cause devastation on a continent sized scale.

All models are is solid agreement that 2004 MN4 has only a 1 in 63 chance of impacting the Earth. So there is a 98.4% chance that it will miss the Earth. On the other hand, no object of this significant size as posed such a known threat to Earth in recorded history. Nothing of even close to this size has ever impacted the Earth during recoded human history.

These models are based on 64 observations made by 10 different observatories over a span of 6 months. That is a long enough observation record confirmed by multiple skilled observers to take seriously.

I'll stress again that there is a 62 out of 63 chance that 2004 MN4 will miss the Earth in 2029-04-13. Even so, this object deserves careful watching. Stay tuned / watch this space for further details.