... An Ion Drive for Deep Space 1 . ... Space travel entered the age of the ion drive in 1998 with the launch of Deep Space 1, a NASA mission designed primarily to test new technologies. Although the ion drive on Deep Space.. ... A planet, a white dwarf, and a neutron star orbit each other in the giant globular star cluster M4, some 5,600 light-years away. ... The Cats Paw Nebula . ... Mars Simulated View . ... Mars is heading for its closest encounter with Earth in over 50,000 years. ...