The Voyager spacecraft, specifically Voyager 1 and Voyager 2, were launched by NASA in 1977 as part of the Voyager program. These spacecraft were designed to explore the outer solar system and provide valuable data about the planets and moons in that region.
While the Voyager spacecraft have achieved remarkable speeds, they are not traveling faster than the speed of light. Instead, they rely on conventional rocket propulsion systems to gradually accelerate them. To achieve the necessary velocity to reach their destinations, the Voyagers used gravity assists from the giant planets in our solar system, particularly Jupiter and Saturn, to gain momentum and change their trajectories.
By performing a series of carefully planned gravity-assist maneuvers, the Voyagers were able to use the gravitational pull of these planets to slingshot them and increase their velocities without expending significant amounts of fuel. This allowed them to reach high speeds relative to the Sun and travel far beyond the inner solar system.
The Voyager spacecraft have been incredibly successful in their mission. Voyager 1 is currently the farthest man-made object from Earth and has officially entered interstellar space, while Voyager 2 has also crossed the heliopause and is expected to enter interstellar space in the future.
It's important to note that the distances the Voyager spacecraft have traveled are still relatively small on the cosmic scale. The vast distances between stars and galaxies make interstellar travel a significant challenge, and current technology and our understanding of physics do not allow us to reach speeds anywhere near the speed of light.