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@Pat
"The success of the mission means we will not have to face the same fate as the dinosaurs...", which MAY BE true, depending on the size of the celestial body on a colliding course with Earth... among other unknowns. 😎
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The larger the asteroid, the further out we can detect it, and therefore the more time we have to divert it. The sooner you hit it, the more it is deflected.
But that's for asteroids in our system. A large, dense rogue planet traveling at very high speed (maybe from a system that went supernova) that arrives in our system may not be able to be deflected in time with our current detection/deflection capabilities.
Thus the "...at least this time."
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@Pat
You said it all.
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@mc
This one is 100% true, although parts of it may seem like they are not.
The asteroid was never on a collision course with Earth. This was just a test of our capability to divert asteroids. Dimorphos was chosen by NASA because it was within telescope range of Earth so as to make observation of its course change easier to determine (among other reasons). This #TruthBeTold implies that the asteroid was going to hit Earth and was prevented from doing so. If you read the #truthbetold carefully, it never explicitly says that the asteroid was going to hit Earth. However, it says, “The success of the mission means we will not have to face the same fate as the dinosaurs...”, which is true. The success of this mission means that we will be able to divert future asteroids which may actually be on a collision course with Earth.