Complex sentence: Development of an asteroid-orbit manipulation infrastructure could offer an irresistible return on investment, however, astrophysicists Carl Sagan and Steven J. Ostro raised the concern that altering the trajectories of asteroids in nearby interplanetary space could cause a catastrophic collision with Earth.
Split into simpler sentences: Development of an asteroid-orbit manipulation infrastructure could offer an irresistible return on investment. However, astrophysicists Carl Sagan and Steven J. Ostro raised the concern that altering the trajectories of asteroids in nearby interplanetary space could cause a catastrophic collision with Earth.