So real, so far away. (Short comment is too long to post: () 1. Stellar winds? Or what is the time scale of young star formation, and how many relativistic effects are there. What a drastic physical experiment. 2. At Hubble's orbital altitude, Observing the earth with the naked eye, how many degrees does the earth measure. 3. To what extent has the innovative propulsion principle (interstellar travel) been implemented in engineering? Or whether there is already a conceptual design. Engineering experience? Theoretical principle? 4. In the history of human aircraft invention, there was a saying: It is nothing to design an aeroplane, making it is something, flying it is everything. Even so, how far have we designed on the journey to the stars?
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