Cometary Delivery
Successful Impact
Below is a movie of the simulated impact for a 1km diameter comet impacting at a 30 degree angle with an impact velocity of 10 km/s. In this impact ~95% of the HCN present survives to the end of the simulation. It is important to note that this impact velocity is below the escape velocity of the Earth and is only possible if the comet is heavily slowed during atmospheric passage, reducing the likelihood of successful delivery.
Unsuccessful Impact
Below is a movie of the simulated impact for a 1km diameter comet impacting head on at 90 degrees with an impact velocity of 20 km/s, around the average impact velocity onto the Earth. In this impact all HCN is destroyed by the end of the simulation.