NASA: Voyager 1
Nasa lauched Voyager 1 in 1977. According to The Register,
NASA’s extraordinarily long-lived Voyager 1 probe this week passed 14 billion miles from Earth.
It takes light nearly 21 hours to reach the spacecraft, making commanding the thing increasingly tricky.
Of course, the distance counter can occasionally roll backwards slightly due to the orbit of the Earth around the Sun, but the milestone is an impressive feat nonetheless.
The spacecraft was a mere 3.7 billion miles from Earth when it snapped the iconic Pale Blue Dot image 30 years ago.
It goes on to say that
Now down to four functioning instruments, Voyager 1 is expected to reach the Oort cloud in approximately 300 years. It fired up its trajectory correction thrusters for the first time in decades in 2017 to keep its antenna pointed toward Earth, adding a few more years to its mission.
The end, alas, is approaching. Over the coming years scientists will be forced to shut down the remaining instruments in order to eke out the probe’s diminishing power supply. By 2025, all the science instruments will have been shut down although there is a good chance engineering data will still be transmitted.