131–140 of 252 posts
From other comments in this thread, it seems this risk has passed, but was known three days ago? Was any action taken at all? A 3% risk isn't small.
I'm having a weirdly difficult time finding some basic ELI5 answers. - What is the probability that this asteroid will hit us? - What is the time interval where that probability applies? - Do we have a probability distribution for where it might hit? I don't know anything about anything, but I assume we know what *general direction* it's coming from? - Do we have a probability distribution for the potential blast rad…
"If it is real this IS the worst asteroid threat ever discovered and the impact location and times are ugly (will post pics shortly). Note that the impact is in the next couple days! However, an Italian colleague of one of our astronomers suspects there is an error in the reported observations and there has been no chatter about this object and no followup. This probably means that it is not real. " - Joel C. Sercel, PhD
I'm guessing the impact death area will be around 3600 km2 (I have no idea, please correct), so ultimately the chance of it falling on me is 1 in 10,000 to 1 in 100,000 provided the asteroid hits. Which means 1 in 1,000,000 to 1 in 10,000,000 in total? (assuming 1% hit probability)
Impact time is in the past. Mission accomplished, everyone!
Am I reading this data correctly?: https://cneos.jpl.nasa.gov/scout/#/object/ZTm0038 Because it looks like today is the most probable day of impact at 10%, but there is a good 25%+ chance it will impact sometime in the next two weeks.
Earlier quoted context omitted.
400m in one dimension leaves a lot of room for variation. 400m x 1m x 1m is a lot less concerning than a 400m diameter sphere.
That would sound like a kinetic bombardment weapon and that we were about to get rodded. My level of concern would be sky high!
> Closest approach time of impactors: t_min = 2023/08/14 04:48 TDB and t_max = 2023/08/15 12:22 TDB If you can read this that means it hasn't hit you.
I'm having a weirdly difficult time finding some basic ELI5 answers. - What is the probability that this asteroid will hit us? - What is the time interval where that probability applies? - Do we have a probability distribution for where it might hit? I don't know anything about anything, but I assume we know what *general direction* it's coming from? - Do we have a probability distribution for the potential blast rad…
When a new potentially-hazardous asteroid is discovered, it's normal for the probability of impact to go up a couple times before abruptly plummeting to zero, as the radius of uncertainty shrinks until it shrinks past the Earth. See https://en.wikipedia.org/wiki/Torino_scale#/media/File:Apoph... . A 3% chance of impact right after discovery with the initial error ellipse isn't all that unusual; it will almost certain…
If these large numbers happen so often that asteroids with initial impact probabilities of 3% are known to actually impact much less frequently than that, then the model is poorly calibrated, no? In other words, the reported probabilities aren't really probabilities and that is what has caused the confusion and anxiety in these comments.
That's what I get for reading HN before going to sleep...
Is this the highest probability assigned to such an object?
Earlier quoted context omitted.
... The Chelyabinsk meteor had ~20m of diameter. The impact energy of a 400m diameter asteroid is somewhere in the same ballpark as the deployed nuclear arsenal of the United States. Not extinction-level impact, but wherever it hit would definitely feel it.
Yes some place will feel it somehow, 70% chance it strikes an ocean and creates a tsunami. But the world will go on, people will shrug their shoulders and go on with life. If it was a 60 mile wide asteroid, now that would truly be the end.