Asteroid Impact on Earth 2032 with Probability 1% and 8Mt Energy

Post by thebruce87m » Thu, Jan 30, 2025, 11:08 AM UTC

jampekka wrote: post #253

insane_dreamer wrote: post #229

Woah. A 1% probability is a lot higher than I expected and am comfortable with (not that I can do anything about it)

Urban areas are only about 0.5% of earth surface, so rough approximation of a catastrophic hit chance is around 0.005%. The chance of you specifically being affected by this asteroid is vanishingly small. You should personally be more worried about crossing a road or plugging in an electric appliance or being hit by a lightning. For others there's a lot more devastation going on globally that you could even do someth…

Post by coderenegade » Thu, Jan 30, 2025, 11:25 AM UTC

moktonar wrote: post #263

coderenegade wrote: post #247

Earlier quoted context omitted.

Energy drift doesn't make the system non-deterministic, it just means that the time evolution has some error. The error is still deterministic. If you simulate a deterministic but chaotic system like n-body orbitals with a non-symplectic integrator, you'll always get the same result for the same initial conditions. The drift created by the finite timestep will also be the same.

It’s the error with the ground truth that you can’t predict. Otherwise you would just be able to cancel it out. You can only predict probability distributions..

Post by hoseja » Thu, Jan 30, 2025, 11:30 AM UTC

coderenegade wrote: post #222

NL807 wrote: post #164

Earlier quoted context omitted.

>it's all deterministic and there is no opposing player making choices It's not deterministic, it's chaotic. That is the nature of the N-body problem. We can only approximate trajectories in such a system using numerical methods, within a certain margin of error. In principle, the object is gravitationally interacting with everything else in the solar system. But for the most part, most interactions are negligible an…

Chaotic doesn't mean non-deterministic, it just means that small changes in initial conditions result in a large change in the trajectory. The system itself can be both chaotic and deterministic. It's also a reasonable question to ask, because the simulations are deterministic. It's just that because the system is also chaotic and there's noise in the measurement, that can result in a large spread of deterministic tr…

Post by Aachen » Thu, Jan 30, 2025, 11:59 AM UTC

ahazred8ta wrote: post #200

dylan604 wrote: post #183

Earlier quoted context omitted.

> but come within like 20 meters of it? like is doing some heavy lifting here. We have had asteroids pass by at a distance closer than the moon. That's pretty damn close in my book relative to the size of the cosmos. At that scale, that's pretty much a ringer in horse shoes. The buzzcut is a very strange question though. If the thing enters the atmosphere and does not burn up, it is hitting the ground.

You are slightly mistaken. There have been hit-and-run asteroids that entered the upper atmosphere and skipped through. https://en.wikipedia.org/wiki/1972_Great_Daylight_Fireball The Grand Teton Meteor / The Great Daylight Fireball of 1972 came within 35 miles of the surface. A huge iron meteor might survive a low pass but this would be a very rare event. https://en.wikipedia.org/wiki/Category:Earth-grazing_firebal..…

Post by XorNot » Thu, Jan 30, 2025, 12:19 PM UTC

perihelions wrote: post #268

XorNot wrote: post #215

Earlier quoted context omitted.

...boomer submarines exist. Nuclear second strike has always been from the submarines, which guarantee a response within minutes. Versus your proposal here of launching a highly visible rocket, to manipulate a highly visible object, with a flight time measured in days to weeks that's mostly ballistic. Frankly: this is strategic nonsense.

It's nonsense today, but technical factors change over time. It's unsafe to try to predict too far ahead.