What to make of Polar Dawn, SpaceX’s latest private space flight? For those who don’t obsessively follow developments in humankind’s ventures away from Earth, SpaceX ran another Billionaire’s Joyride recently, with one billionaire, Elon Musk, launching another billionaire, Jared Isaacman and three passengers, into high Earth orbit. At an altitude of 1,408 kilometers, it’s the…