AFTER YEARS of promises, Virgin Galactic's VSS Unity "suborbital spaceliner" has made good on its name, ascending to an altitude of 51.4 miles over the Mojave Desert on December 13. It has become a spaceliner if one accepts the U.S. Air Force policy of issuing astronaut wings to pilots who ascend to an altitude of 50 miles. Another widely-used boundary of where space begins, the Karman Line, is still about 10.5 miles higher than Virgin's spacecraft (or wannabe spacecraft, depending) has flown. This fourth carrier airplane-launched test flight of the Unity beat the altitude of the prior test by a margin of 19 miles, the biggest leap forward-that is, upward-since Virgin unveiled the craft in 2016.
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