The Voyager 1 spacecraft has officially left the solar system and is exploring a cold, dark region of the galaxy, NASA said Thursday of the pioneering probe launched in 1977.
"Now that we have new, key data, we believe this is humankind's historic leap into interstellar space," said Ed Stone, Voyager project scientist based at the California Institute of Technology, Pasadena.
"The Voyager team needed time to analyze those observations and make sense of them. But we can now answer the question we've all been asking: 'Are we there yet?' Yes, we are."