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SpaceX's innovation includes recovering and reusing the first stage. After separation, the first stage flips around, ignites its engines for a controlled descent (boostback burn), and performs a landing burn to slow down for landing either on a drone ship at sea or back at the launch site.
So just like the app that can listen to a song and it will tell you the title Well this App does the same thing only for birds check out this link Merlin bird ID
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