Jeff Bezos, Richard Branson and where space really begins

Scientists say determining the boundaries of space is fuzzy, but billionaires Jeff Bezos and Richard Branson have ignited the debate as they race to jump-start a space-tourism industry. For much of the world, the boundary to space is considered the imaginary Karman Line, which starts around 62 miles above Earth and which Mr. Bezos and his Blue Origin LLC capsule is scheduled to cross on Tuesday. However, she said, applying that definition to Earth, where the base of the exosphere is around 435 miles high, would mean the Hubble Space Telescope and International Space Station are still in Earth’s atmosphere. As for whether Virgin passengers should get an asterisk for not passing the Karman Line, Mr. Chamitoff said, “That’s kind of silly." Mr. Branson said his Virgin Galactic experience Sunday “was beyond my wildest dreams" and that he took notes to enhance the trip for the company’s future passengers.