TFLYTSNBN wrote:doug941 wrote:It more or less checks out with my admittedly hamfisted calculations, allowing for various assumptions. The given energy yield is about 7000 times worse than what the dinosaurs got - and that's just Hammer Alpha.
Concerning the question of RFC's numbers, there is an asteroid impact simulator at "www.purdue.edu/impactearth"
that allows you to play around with various data points. Using a 25km iron asteroid hitting at an angle of 64 degrees at 56km/s and hitting dry sedimentary rock gives a yield of 2.45x10^10 megatons. Can you say "Oooops?"
Weber's numbers are closer to my calculations then this on line calculator..
Lots of wiggle room for asteroud shape , spherical, oblate spheroid, prolate spheroid and density.
Does he say if Beta is bigger than Alpha?
That calculator is suspicious because impact angle is irrellevant unless it just grazes the planet.
Any crater greater than 100 km in diameter is likely to excavate the crust to expose the molten mantle. The heat energy of the exposed magma will multiple the energy release and environmental effects.
It is a shame that the colony ship didnt arrive prior to asteroid impact. They could have nudged the asteroids so that they would miss the planet.[/quote]
"Lots of wiggle room?" At Alpha's speed and mass, shape is meaningless. Angle is meaningless AT THIS SIZE. If the asteroid is measured in 10s or 100s of meters in diameter, the angle of impact is very important. The perimeters for Alpha were vague except for angle "an angle of sixty-four degrees." Speed and size were given as "traveling at over 50kps" and "no more than twenty-five kilometers." Composition of the asteroid and the ground it hit are not mentioned at all.
The Alpha vs Beta size is quoted as "Beta was smaller than Alpha, but its ocean impact had made it even deadlier, in its own way."
Lastly, you are assuming the crust of Calvin III is similar to Earth's. On Earth, that impact simulation WILL penetrate deep enough to fracture though to the mantle. On Calvin III??? Who knows.