- Reusable spacecraft passes tests, approaches flight readiness
- Skylon promises cheap, frequent travel into orbit and deep space
- Could also allow exoplanet exploration and colony construction
(CNN)More than half a century after Sputnik, space travel remains shockingly wasteful. Every rocket we launch at the cost of hundreds of millions of dollars can only be used once and completes its mission by falling to Earth in pieces. This disposable design has scarcely advanced since the 1960s.