Collision Coming!
Explanation:
Peter writes, LPOD shows images of the wounds which were inflicted on the moon over it's long life. It must have been an awesome sight to see an asteroid make it's final approach to the Moon, where it's long journey will come to an end. No human ever witnessed it. Through combining an asteroid image with an image of the Moon, I made an attempt to grasp the atmosphere of such a final moment. This image is a "fantasy" combination of two images by the Galileo spacecraft: asteroid Ida and the south polar region of the Moon.
Ida is 52 km long and its impact on the Moon at 20 km/s would produce a multi-ring basin approximately 500 km wide and moonquakes of magnitude 11! Abundant ejecta would rain down on Earth, producing phenomenal meteor showers and perhaps secondary craters on Earth! The van der Haar basin would be about the size the Mare Crisium, but because the Moon has cooled so much it no longer is melting material in its mantle to erupt as mare basalts - van der Haar would be a dry basin except for any impact melts. It would be safer for humanity, but tragic for observers, if the impact occurred on the far side of the Moon!
