NASA has confirmed that its Voyager 1 spacecraft has become the first human-made object ever to leave the solar system.
It has taken the craft 36 years to reach the milestone, which is being hailed as one of the most significant technological and scientific achievements in history.
In 1977 NASA launched Voyager 1 and a twin Voyager 2. Both flew past Jupiter and Saturn and Voyager 2 also flew past Uranus and Neptune. Both craft have continued to transmit back data every day, though the signals have become increasingly dim.
Voyager 1 first detected increased pressure of interstellar space in 2004. The team of scientists then increased their search for evidence that the craft had actually left the solar system and entered interstellar space.
However, new and unexpected data indicates that Voyager 1 has actually been travelling through the plasma or ionised gas present in the space between stars for the past year.
A report of the evidence has been published this evening in the journal Science. It is thought the craft left the solar system around 25 August last year. It is now situated about 19.3bn kilometres from our Sun.
"Voyager has boldly gone where no probe has gone before, marking one of the most significant technological achievements in the annals of the history of science, and adding a new chapter in human scientific dreams and endeavours," said John Grunsfeld, NASA's associate administrator for science in Washington.
"Perhaps some future deep space explorers will catch up with Voyager, our first interstellar envoy, and reflect on how this intrepid spacecraft helped enable their journey."
